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Дистанционная фотоплетизмография: теория и практика

Добрый день! Меня зовут Иван, я закончил медицинский институт как врач‑терапевт и в настоящее время учусь на 2-м курсе магистратуры МФТИ по направлению «Прикладной анализ данных в медицине». Я прохожу стажировку в Центре искусственного интеллекта в медицине в Лаборатории искусственного интеллекта в Сбере и хочу рассказать о своей работе в области дистанционной фотоплетизмографии. Настоящее исследование продолжает цикл статей о дистанционной фотоплетизмографии в Лаборатории искусственного интеллекта в Сбере [44].

Фотоплетизмография (ФПГ) — это диагностический метод, который позволяет оценить изменения объема крови в микрососудах из‑за сердечных сокращений и получить таким образом информацию о работе сердца и о состоянии сосудов.

Фотоплетизмография находит широкое применение в клинической практике — она лежит в основе пульсоксиметрии (измерении уровня кислорода в крови), используется для подсчета частоты дыхательных движений, оценки тонуса и жесткости сосудистой стенки при артериальной гипертонии, ишемической болезни сердца и заболеваниях периферических сосудов. Активно исследуется применение фотоплетизмографии для предсказания риска фибрилляции предсердий, сахарного диабета, обструктивного апноэ во сне и других заболеваний. Таким образом, фотоплетизмография может использоваться как для диагностики, так и для мониторинга различных витальных показателей [39, 40].

Классическая контактная фотоплетизмография основана на оптической денситометрии — определении оптической плотности ткани. Участок кожи, например, на пальце, освещается красным и инфракрасным светом, который после отражения или прохождения через ткань регистрируется сенсором. При этом наблюдаются пульсации света, отражающие пульсирующий характер кровотока в микрососудах. В зависимости от расположения источника и приемника светового сигнала различают два типа фотоплетизмографических сенсоров: 1) «на пропускание» (трансмиссионные сенсоры), когда источник и приемник расположены с противоположных сторон от объекта исследования, например, пальца; 2) «на отражение» (рефлективный сенсоры), когда источник и приемник расположены с одной стороны от объекта исследований (рис. 1) [2]. Пример получаемого пульсового сигнала приведен на рис. 2.

Рисунок 1 [40]. Контактная фотоплетизмография бывает трансмиссивная (а) и рефлективная (б).

Рисунок 2. Пример пульсового сигнала, получаемого при контактной фотоплетизмографии. Данные взяты из датасета UBFC-rPPG [37].

В последние годы в качестве альтернативы контактной фотоплетизмографии активно развивается дистанционная фотоплетизмография. Она основана на том, что изменение кровенаполнения мелких сосудов влияет на процесс отражения света [11]. Отраженный свет записывается видео‑камерой и анализ полученного видео позволяет выделить искомый пульсовой сигнал. При этом не требуется использование каких‑либо специальных сенсоров как в классической ФПГ.

Мы начнем с описания физиологических основ и алгоритмов дистанционной фотоплетизмографии, после чего обсудим ряд технических аспектов, влияющих на ее точность и эффективность. Последний раздел статьи посвящен проведенным экспериментам и их результатам.

1. Физиологические и алгоритмические основы дистанционной фотоплетизмографии

Дистанционная фотоплетизмография основана на том, что изменение кровенаполнения сосудов из‑за сердечных сокращений вызывает незначительные изменения окраски кожи. Данные изменения неразличимы для человеческого глаза, но могут быть проанализированы с помощью специальных алгоритмов для получения пульсового сигнала. Последний может быть использован для подсчета частоты сердечных сокращений или оценки вариабельности сердечного ритма.

Таким образом, в дистанционной ФПГ можно выделить несколько стандартных шагов, общих для всех классических алгоритмов обработки сигналов (рис. 3). Сначала на кадрах видеозаписи выбирается область интереса — лицо или его отдельный регион. Далее извлекается RGB‑сигнал — считается среднее значение RGB‑каналов в каждом кадре. Полученный RGB‑сигнал может дополнительно фильтроваться, а далее используется для извлечения пульсового сигнала с помощью одного из алгоритмов. Наконец, пульсовой сигнал фильтруется и на его основе производится подсчет частоты сердечных сокращений.

Рисунок 3. Стандартные этапы при дистанционной фотоплетизмографии: выбор области интереса, подсчет RGB-сигнала, применение одного из алгоритмов для получения пульсового сигнала, его фильтрация и подсчет частоты сердечных сокращений [30].

В настоящее время существует ряд методов обработки сигналов для дистанционной фотоплетизмографии. Мы опишем несколько из них, разберем преимущества и недостатки.

1.1. Метод Green

Цветовые каналы в RGB‑видео несут различную пульсовую информацию. Зеленый G‑канал содержит наиболее выраженный пульсовой компонент, так как (окси)‑гемоглобин в эритроцитах сильнее поглощает зеленый спектр по сравнению с красным. Кроме того, зеленый свет проникает глубже в кожу по сравнению с синим светом и таким образом лучше достигает сосудистого русла [3]. Результаты исследования на нескольких датасетах, показали, что наиболее информативным во всех случаях является G‑канал. На втором месте чаще всего находится B‑канал, а на третьем — R‑канал, однако в отдельных случаях разница между B‑ и R‑каналами не является статистически значимой [1]. Когда объем крови в сосуде возрастает, то большое количество гемоглобина поглощает больше света, поэтому отраженная часть света уменьшается, что и ведет к формированию пульсаций в сигнале [41].

Простейшая идея — это использовать G‑канал как наиболее информативный для определения пульса, что и было предложено в одном из первых методов дистанционной фотоплетизмографии, который получил название Green [3]. Первый этап, стандартный для большинства алгоритмов, состоит в пространственной нормализации. На каждом кадре в видео выбирается область интереса (лицо или отдельная его часть) и считается среднее значение G‑канала среди всех пикселей в данной области. Аналогичным образом проводится усреднение и двух других каналов, в методах, которые их используют. В методе Green сигнал из G‑канала фильтруется, чтобы оставить частоты в диапазоне соответствующем 40–240 ударам в минуту, после чего доминантная частота сигнала используется для оценки частоты пульса.

Однако, при таком подходе не учитывается информация, доступная в других каналах. Поэтому вслед за этим методом был предложен алгоритм G‑R, который дополнительно использует красный канал, вычитая его из зеленого [4]. Вычитание R‑канала оказывает положительный эффект, так как учитывает физиологическую информацию — G‑ и R‑каналы содержат максимальную и минимальную пульсовые амплитуды, поэтому их комбинация максимизирует пульсовой сигнал. Несмотря на свою простоту, данный метод показывает достаточно хорошие результаты (сравнение с другими методами приведено в разделе 3 в табл. 2).

1.2. Дихроматическая модель

Видимые изменения окраски кожи происходят согласно физиологическим особенностям отражения света от кожи, поэтому для лучшего понимания алгоритмов дистанционной фотоплетизмографии нам необходимо рассмотреть механизмы данного процесса. Согласно дихроматической модели при падении света на кожу одна его часть отражается непосредственно от поверхности кожи (зеркальное отражение), а другая — проникает в подлежащие ткани, где частично рассеивается, а частично, достигнув кровеносных сосудов, — отражается от них (диффузное отражение) [5, 11]. Описанный процесс схематично проиллюстрирован на рис. 4. Очевидно, что только диффузно отраженная часть светового потока содержит информацию о кровенаполнении сосудов и может использоваться для анализа пульса.

Рисунок 4. При падении света на кожу одна его часть отражается непосредственно от поверхности кожи (зеркальное отражение – specular reflection), а другая – проникает в подлежащие ткани, где частично рассеивается, а частично, достигнув кровеносных сосудов, – отражается от них (диффузное отражение – diffuse reflection) [5].

Световой поток, падающий на сенсор RGB-камеры, может быть представлен в виде зависимой от времени {(t)} функции:

$\begin{equation} C(t)=I_0 \cdot (1+i(t)) \cdot (u_c \cdot c_0 + u_s \cdot s(t) + u_p \cdot p(t)) \tag{1} \end{equation} ,$

где {C(t)} — это среднее значение RGB‑каналов в области интереса, {I(t)} — интенсивность светового потока, которая модулируется двумя компонентами — зеркальным отражением ${v_s(t)}$ и диффузным отражением ${v_d(t)}$ . Последний компонент ${v_n(t)}$ — это шумовой сигнал сенсора камеры. Однако мы делаем допущение, что благодаря относительному большому размеру области интереса шум камеры ${v_n(t)}$ является незначимым и может не учитываться. В отдельных областях зеркальное отражение может преобладать над диффузным. Но мы также делаем допущение, что благодаря эффективному выбору области интереса участки с доминирующим зеркальным отражением не рассматриваются.

Зеркальное отражение ${v_s(t)}$ изменяется при движениях, так как последние влияют на геометрические отношения между источником света, поверхностью кожи и камерой. Таким образом,

$\begin{equation} v_s(t)=u_s \cdot (s_0 + s(t)) \tag{2} \end{equation} ,$

где ${ u_s}$ – это спектр света, ${s_0}$ – стационарный компонент, а ${s_t}$ – компонент, зависимый от времени, а точнее говоря – от движений.

Диффузное отражение v_d(t) зависит от поглощения и рассеивания света в тканях под кожей и определяется в первую очередь постоянным уровнем меланина – пигмента, обуславливающим цвет кожи, и зависимым от времени (от кровенаполнения сосудов) уровнем гемоглобина. Таким образом,

$\begin{equation} v_d(t)=u_d \cdot d_0 + u_p \cdot p(t) \tag{3} \end{equation} ,$

где ${u_d}$ — постоянный компонент цвета кожи, d_0 — постоянный коэффициент отражения, ${u_p}$ — относительная сила пульсового сигнала в RGB каналах, а {p(t)} — непосредственно пульсовой сигнал.

Подставив {(2)} и {(3)} в {(1)} получим:

$\begin{equation} C(t)=I(t) \cdot (u_s \cdot (s_0 + s(t)) + u_d \cdot d_0 + u_p \cdot p(t)) \tag{4} \end{equation} ,$

Постоянные компоненты зеркального и диффузного отражений могут быть объединены в единый компонент:

$\begin{equation} u_c \cdot c_0 = u_s \cdot s_0 + u_d \cdot d_0 \tag{5} \end{equation} ,$

где ${u_c}$ – цвет отражаемого светового потока, а ${c_0}$ – сила отражения. Подставим {(5)} в {(4)} , получим:

$\begin{equation} C(t)=I_0 \cdot (1+i(t)) \cdot (u_c \cdot c_0 + u_s \cdot s(t) + u_p \cdot p(t)) \tag{6} \end{equation} ,$

где яркость светового потока {I(t)} также представлена в виде постоянного I_0 и зависимого от времени $I_0 \cdot i(t)$ компонентов.

В сигнале, получаемом из светового потока, условно различают две части – пульсирующую переменную часть {AC} , которая зависит от пульса, и непульсирующую медленно изменяющуюся часть {DC} , которая определяется медленным изменением кровенаполнения венозных и артериальных сосудов, а также изменением объема межклеточной жидкости и другими физиологическими процессами, влияющими на оптические свойства биологической ткани [2]. Раскрыв скобки в {(6)} , можно упростить выражение, так как компонент {AC} на порядок меньше компонента {DC} , и их произведения ${s(t) \cdot i(t)}$ и ${ p(t) \cdot i(t)}$ могут быть отброшены:

$\begin{equation} \begin{aligned} C(t) &= u_c \cdot I_0 \cdot c_0 + u_s \cdot I_0 \cdot s(t) + u_p \cdot I_0 \cdot p(t) + \\ &\quad + u_c \cdot I_0 \cdot c_0 \cdot i(t) + u_s \cdot I_0 \cdot s(t) \cdot i(t) + u_p \cdot I_0 \cdot p(t) \cdot i(t) \\ &\approx u_c \cdot I_0 \cdot c_0 + u_c \cdot I_0 \cdot i(t) + u_s \cdot I_0 \cdot s(t) + u_p \cdot I_0 \cdot p(t). \end{aligned} \tag{7} \end{equation}$

Для наглядности еще раз отметим роль отдельных компонентов в {(7)} :

$u_c \cdot I_0 \cdot c_0$ – это постоянная интенсивность света;

$u_c \cdot I_0 \cdot c_0 \cdot i(t)$ – это изменения интенсивности света, которые вызваны, главным образом, движениями;

$u_s \cdot I_0 \cdot s(t)$ – это компонент, связанный с зеркальным отражением света от поверхности кожи;

$u_p \cdot I_0 \cdot p(t)$ – это искомый пульсовой сигнал.

Таким образом, {C(t)} – это линейная комбинация сигналов, и ключевая задача алгоритма дистанционной фотоплетизмографии состоит в извлечении пульсового сигнала из {(7)} . Существующие методы можно разделить на две категории – основанные на слепом разделении сигнала (методы главных и независимых компонент) и учитывающие физиологические особенности процесса светоотражения. Мы начнем с рассмотрения алгоритма CHROM, который предоставит интуитивно понятную мотивацию для ряда ключевых концепций, используемых и в других алгоритмах.

1.3. Метод CHROM

Изменение амплитуды пульсового сигнала в каждом из RGB-каналов зависит от интенсивности источника света [12, 11]. Для того, чтобы устранить постоянное влияние интенсивности и цвета источника света на пульсовой сигнал следует выполнить временную нормализацию каждого из RGB-каналов – разделить сигнал ${C_i(t)}$ в каждом из каналов на среднее значение сигнала в канале за время ${\mu (C_i(t))}$ :

$\begin{equation} C_ni(t) = \frac {C_i(t)} { \mu (C_i(t))} \tag{8} \end{equation} .$

Нормализация во времени является одним из ключевых этапов алгоритмов, которые основаны на работе в нормализованном во времени RGB-пространстве. К таким алгоритмам относятся CHROM и POS.

Однако временная нормализация не может устранить влияние изменений интенсивности светового потока за период, во время которого проводится нормализации [12]. Подобные изменения обычно возникают из-за движений поверхности кожи относительно источника света. Предположив, что изменения интенсивности одинаковы для всех RGB-каналов, можно устранить их, взяв отношение двух нормализованных во времени RGB-каналов. Так как, как уже было отмечено, G- и R-каналы содержат максимальную и минимальную пульсовые амплитуды, можно взять их отношение, получив пульсовой сигнал, на который устранено влияние движений:

$\begin{equation} S = \frac {G_n(t)} { R_n(t)} -1 \tag{9} \end{equation} .$

Единица вычитается для приведения сигнала к виду, где среднее значение равно нулю. Недавно были также предложены методы GB и GRGB, в которых вместо отношения ${G_n(t) / R_n(t)}$ используются соответственно ${G_n(t) / B_n(t)}$ и ${G_n(t) / R_n(t)} + {G_n(t) / B_n(t)}$ [6].

Отношение двух каналов позволяет устранить влияние изменений интенсивности, но не может убрать влияние зеркального отражения от поверхности кожи. Отметим, что, в то время как диффузный компонент, несущий пульсовой сигнал, различен для RGB-каналов из-за особенностей абсорбции света тканями, зеркальный компонент, несущий шум, является одинаковым во всех RGB-каналах.

При использовании источника белого света зеркальный компонент привносит одинаковую фракцию белого света, которую можно устранить, используя разницу между цветовыми каналами, то есть цветность (chrominance). Из трех RGB-каналов можно получить два ортогональных сигнала цветности:

$\begin{equation} X=R-G, \\ Y=0,5R + 0,5G - B \tag{10} \end{equation} .$

При этом изменения, вызванные пульсовой волной, будут различаться для них, а изменения, вызванные движениями, будут одинаковыми. Используя описанный ранее подход {(9)}, можно взять их отношение, чтобы устранить влияние движений, получив пульсовой сигнал:

$\begin{equation} S = \frac {X_n} { Y_n } -1 = \frac {R-G} {0,5R+0,5G-B } -1 \tag{11} \end{equation} .$

Еще раз отметим смысл каждого из данных этапов:

1) временная нормализация {(8)} позволяет устранить влияние постоянного уровня интенсивности света ${(u_c \cdot I_0 \cdot c_0)}$ на пульсовой сигнал;

2) разница между цветовыми каналами позволяет устранить зеркальное отражение ${(u_s \cdot I_0 \cdot s(t))}$ , одинаковое во всех RGB каналах, получив в результате два сигнала цветности {(10)} ;

3) отношение двух сигналов цветности в {(11)} позволяет устранить влияние изменений интенсивности света из-за движений ${(u_c \cdot I_0 \cdot c_0 \cdot i(t))}$ .

Данный подход, однако, справедлив только при использовании источника белого света. Под источником света другого цвета алгоритм будет работать хуже. Для устранения означенного недостатка можно выполнить стандартизацию цвета кожи. В ходе эксперимента было установлено, что стандартизированный цвет кожи под источником белого света почти одинаков у всех людей:

$\begin{equation} u_{skin} = \frac {[R,G,B]} { \sqrt{R^2 + G^2 + B^2} } \tag{12} \end{equation} .$

Стандартизированный цвет кожи, конечно же, отличается в зависимости от цветотипа кожи (уровня меланина), однако различия невелики и потому пренебрежимы. Хотя более высокий уровень меланина усиливает абсолютное поглощение света кожей, поглощение света в разных RGB-каналах относительно друг друга остается почти одинаковым. Поэтому стандартизированный цвет кожи под источником белого света почти одинаков у всех людей [11].

Таким образом, для того чтобы выполнить поправку для источника света другого цвета, необходимо выполнить временную нормализацию каждого RGB-канала, используя {(8)} , а затем умножить на стандартизированный вектор цвета кожи {(12)} :

$\begin{equation} R_s=0,7682R_n,G_s=0,5121G_n,B_s=0,3841B_n \tag{13} \end{equation}.$

Далее подставим {(13)} в {(11)} :

$\begin{equation} S = \frac {X_s} { Y_s} -1 \tag{14} \end{equation} .$

$\begin{equation} \begin{aligned} X_s &= \frac{R_s - G_s}{0,7682 - 0,5121} = 3R_n - 2G_n, \\ Y_s &= \frac{R_s + G_s - 2B_s}{0,7682 + 0,5121 - 2 \cdot 0,3841} = 1,5R_n + G_n - 1,5B_n \end{aligned} \tag{15} \end{equation}$

Отметим, что изначально авторы в {(10)} выбрали {Y} как {Y=0,5R+0,5G-B} , однако в { (15) } , чтобы убрать дробные коэффициенты {0,5} , используют {Y=R+G-2B} . Очевидно, что результат будет тем же самым. Также отметим, что в {(10) } {X} представлен как {X=R-G} , a {Y} – как {Y=0,5R+0,5G-B} . Однако в { (15) } мы дополнительно добавляем знаменатели, для того чтобы вклад каждого из цветовых каналов имел корректный вес, соответствующий таковому при источнике света белого цвета. Мы можем расписать { (15) } чуть подробнее, чтобы увидеть, как получаются итоговые коэффициенты:

$\begin{equation} \begin{aligned} X_s &= \frac{R_s - G_s}{0{,}7682 - 0{,}5121} = \frac{0{,}7682R_n - 0{,}5121G_n}{0{,}7682 - 0{,}5121} \\ &= \frac{0{,}7682R_n - 0{,}5121G_n}{0{,}2561} \approx 2{,}999R_n - 1{,}999G_n \approx 3R_n - 2G_n. \end{aligned} \tag{16} \end{equation}$

Аналогичным образом:

$\begin{equation} \begin{aligned} Y_s & = \frac{R_s + G_s - 2B_s}{0,7682 + 0,5121 - 2 \cdot 0,3841} = \frac{0,7682R_n + 0,5121G_n - 2 \cdot 0,3841B_n}{0,7682 + 0,5121 - 2 \cdot 0,3841} \\ & = \frac{0,7682R_n + 0,5121G_n - 0,7682B_n}{0,7682 + 0,5121 - 0,7682} = \frac{0,7682R_n + 0,5121G_n - 0,7682B_n}{0,5121} \\ & \approx 1,500R_n + G_n - 1,500B_n \approx 1,5R_n + G_n - 1,5B_n. \end{aligned} \tag{17} \end{equation}$

Далее мы можем упростить {(14)} , используя свойства логарифмов и серию Тейлора:

$\begin{equation} log(1+s) = log(\frac {X_s} { Y_s} ) = log(X_s) - log(Y_s) \tag{18} \end{equation} ,$

$\begin{equation} log(x) = (x-1) - \frac {(x-1)^2} { 2)} + \frac {(x-1)^3} { 3)} -... \tag{19} \end{equation}$

Так как все аргументы логарифмов в {(18)} близки к единице, то

$\begin{equation} S≈X_s-Y_s=3R_n-2G_n-(1,5R_n+G_n-1,5B_n )=1,5R_n-3G_n+1,5B_n \tag{20} \end{equation} .$

Наконец, отметим, что амплитуда пульса {S} может быть сравнительно маленькой относительно ${X_s}$ и ${Y_s}$ . Если стандартизация цвета кожи окажется не совсем точной, то ${X_s}$ и ${Y_s}$ будут иметь разные амплитуды. Для коррекции можно использовать следующий механизм, называемый альфа-тюнингом:

$\begin{equation} S=X_s-αY_s,α= \frac {σ(X_s )} {σ(Y_s )} \tag{21} \end{equation} .$

Он обусловлен тем, что пульсовой сигнал находится в противофазе между ${X_s}$ и ${Y_s}$ , а искажения из-за изменений интенсивности светового потока при движениях находятся в фазе между ${X_s}$ и ${Y_s}$ . Таким образом, когда доминирует пульсовой компонент, то ${S_1}$ и ${S_2}$ находятся в противофазе, и поэтому их разность помогает усилить пульсовой сигнал. Если же доминируют искажения, обусловленные движениями, то разность их двух сигналов, находящихся в фазе, позволяет устранить данные искажения. Полученный алгоритм {(21)} основан на использовании двух сигналов цветности (chrominance), поэтому называется CHROM [12].

1.4. Методы слепого разделения сигнала

Метод главных компонент (PCA) и метод независимых компонент (ICA) [13, 14] позволяют разделить RGB сигнал {C(t)} на отдельные компоненты {Y(t)} , соответствующие интенсивности света, зеркальному отражению от кожи и диффузному отражению, несущему искомый пульсовой сигнал, с помощью матрицы {W} :

$\begin{equation} Y(t)=W·C(t) \tag{22} \end{equation} .$

Хотя алгоритмы слепого разделения сигналов на первый взгляд сильно отличаются от метода CHROM, отметим, что все они направлены на выделение пульсового сигнала как некой линейной комбинации сигналов из трех RGB-каналов. CHROM использует для этого постоянные во всех случаях коэффициенты в {(20)} :

$\begin{equation} S≈1,5R_n-3G_n+1,5B_n \tag{20} \end{equation} .$

a PCA и ICA – линейную комбинацию, определенную на основе {(22)} :

$\begin{equation} S=w_1 R_n-w_2 G_n+w_3 B_n \tag{23} \end{equation} .$

Разница между PCA и ICA заключается в их допущениях относительно указанных компонент: PCA предполагает, что они некоррелированные, а ICA – что они независимые. После разложения из {Y(t)} выбирается наиболее периодический сигнал как отражающий пульсовой компонент. Вследствие этого данные методы не работают, если движения человека также являются периодическими (например, при занятиях спортом). Более того другие частотные составляющие (например, дыхание) также затрудняют нахождение {W} [5]. Наконец, для корректного определения пульса необходимо использовать достаточно длинное видео (около 25 с), в то время как CHROM показывает хорошие результаты при работе и на значительно более коротких фрагментах [12]. Таким образом, благодаря учету особенностей физиологии и процесса отражения света CHROM демонстрирует лучшие результаты.

1.5. Временная нормализация и дихроматическая модель

Прежде чем перейти к описанию метода POS отметим более детально роль временной нормализации {(8)} в дихроматической модели {(7)} [5].

$\begin{equation} C(t) \approx u_c \cdot I_0 \cdot c_0 + u_c \cdot I_0 \cdot i(t) + u_s \cdot I_0 \cdot s(t) + u_p \cdot I_0 \cdot p(t) \tag{7}. \end{equation}$

Среднее во времени значение RGB-каналов ${\overline{C}(t) }$ отражает постоянный в течение определенного времени компонент светового потока: ${\overline{C}(t) \approx u_c \cdot I_0 \cdot c_0}$ , и может использоваться для временной нормализации исходного сигнала {C(t)} путем определения матрицы нормализации {N} , такой что

$\begin{equation} N \cdot \overline{C}(t) \approx u_c \cdot I_0 \cdot c_0 = 1. \tag{24} \end{equation}$

Таким образом, получим нормализованный во времени сигнал ${ C_n(t)}$ :

$\begin{equation} \begin{aligned} C_n(t) &= N \cdot C(t) \\ &= N \cdot u_c \cdot I_0 \cdot c_0 + N \cdot u_c \cdot I_0 \cdot c_0 \cdot i(t) + \\ &\quad+ N \cdot u_s \cdot I_0 \cdot s(t) + N \cdot u_p \cdot I_0 \cdot p(t) \\ &= 1 \cdot (1 + i(t)) + N \cdot u_s \cdot I_0 \cdot s(t) + N \cdot u_p \cdot I_0 \cdot p(t) \end{aligned} \tag{25} \end{equation}$

Отметим, что ${1 \cdot (1 + i(t))}$ — это изменение интенсивности света в направлении вектора {1} , который является вектором нормализованного во времени цвета кожи. Это наибольший компонент, изменения которого обусловлены движениями, и он одинаково представлен во всех RGB каналах. ${ N \cdot u_s \cdot I_0 \cdot s(t) }$ — это компонент зеркального отражения, а ${ N \cdot u_p \cdot I_0 \cdot p(t) }$ — это пульсовой сигнал.

Также приведем сигнал к форме, где среднее значение цвета равно нулю:

$\begin{equation} \tilde{C}_n(t) = C_n(t) - 1 = 1 \cdot i(t) + N \cdot u_s \cdot I_0 \cdot s(t) + N \cdot u_p \cdot I_0 \cdot p(t). \tag{26} \end{equation}$

1.6. Метод CHROM и дихроматическая модель

Перед обсуждением метода POS мы сделаем еще одно отступление и обсудим описанный ранее метод CHROM с позиций дихроматической модели [5]. Это позволит в дальнейшем подчеркнуть сходства и различия алгоритмов POS и CHROM, которые очень близки друг другу и отличаются, в сущности, лишь порядком выполняемых операций.

Метод CHROM работает в нормализованном во времени RGB-пространстве и состоит из двух ключевых и одного промежуточного этапов:

1) Проекция в направлении стандартизированного вектора цвета кожи под источником белого света ${u_{skin}}$ , чтобы выполнить поправку для источника света другого цвета. Данный этап является промежуточным так как необходим только в условиях освещения не соответствующих белому свету;

2) Проекция в ортогональную относительно зеркального отражения плоскость, чтобы устранить влияние зеркального отражения. В дихроматической модели {(26)} это – проекция ортогональная компоненту ${ (N \cdot u_s \cdot I_0 \cdot s(t)) }$ ;

3) Альфа-тюнинг для устранения искажений, вызываемых изменением интенсивности светового потока из-за движений.

Следуя описанию в [5], мы можем объединить первые два этапа в умножение на единую проекционную матрицу. На основе вектора ${u_{skin} = [0.7682; 0.5121; 0.3841]}$ создадим диагональную матрицу ${U_{skin}}$ , так что ${U_{skin}^{-1} \cdot u_{skin} = 1}$ :

$\begin{equation} U_{{skin}} = \begin{pmatrix} 0,7682 & 0 & 0 \\ 0 & 0,5121 & 0 \\ 0 & 0 & 0,3841 \end{pmatrix}. \tag{27} \end{equation}$

Матрица ${P_{Chrom}}$ для проекции в ортогональном относительно зеркального отражения направлении — это матрица коэффициентов, используемых для получения двух ортогональных сигнала цветности в {(10)} :

$\begin{equation} P_{{Chrom}} = \begin{pmatrix} 1 & -1 & 0 \\ 0,5 & 0,5 & -1 \end{pmatrix}. \tag{28} \end{equation}$

где строки соответствуют двум сигналам цветности, а столбцы – коэффициентам RGB-каналов. Умножим ${P_{{Chrom}}}$ и ${U_{skin}}$ :

$\begin{equation} \begin{aligned} P_{{Chrom}} \cdot U_{{skin}} &= \begin{pmatrix} 1 & -1 & 0 \\ 0.5 & 0.5 & -1 \end{pmatrix} \begin{pmatrix} 0,7682 & 0 & 0 \\ 0 & 0,5121 & 0 \\ 0 & 0 & 0,3841 \end{pmatrix} \\ &= \begin{pmatrix} 0,7682 & -0,5121 & 0 \\ 0,3841 & 0,2561 & -0.3841 \end{pmatrix}. \end{aligned} \tag{29} \end{equation}$

Чтобы показать эквивалентность полученной проекционной матрицы коэффициентам в оригинальной статье про CHROM выполним несколько простейших преобразований. Разделим каждую строку на наименьший по модулю ненулевой элемент:

$\begin{equation} \begin{aligned} \begin{pmatrix} \frac{0,7682}{0,5121} & -\frac{0,5121}{0,5121} & 0 \\ \frac{0,3841}{0,2561} & \frac{0,2561}{0,2561} & -\frac{0.3841}{0,2561} \end{pmatrix} &= \begin{pmatrix} 1,5 & -1 & 0 \\ 1,5 & 1 & -1,5 \end{pmatrix}. \end{aligned} \tag{30} \end{equation}$

Умножив первую строку на {2} , мы получим матрицу коэффициентов, как и в оригинальной статье:

$\begin{equation} \begin{aligned} \begin{pmatrix} 1,5 \cdot 2 & -1 \cdot 2 & 0 \\ 1,5 & 1 & -1,5 \end{pmatrix} = \begin{pmatrix} 3 & -2 & 0 \\ 1,5 & 1 & -1,5 \end{pmatrix}. \end{aligned} \tag{31} \end{equation}$

Возвращаясь к дихроматической модели {(26)} , рассмотрим результат проекции нормализованного во времени сигнала:

$\begin{equation} \tilde{C}_n(t) = C_n(t) - 1 = 1 \cdot i(t) + N \cdot u_s \cdot I_0 \cdot s(t) + N \cdot u_p \cdot I_0 \cdot p(t), \tag{26} \end{equation}$

$\begin{equation} S(t) = P_{{Chrom}} \cdot U_{{skin}} \cdot \tilde{C}_n(t) \approx P_{{Chrom}} \cdot U_{{skin}} \cdot 1 \cdot i(t) + P_{{Chrom}} \cdot U_{{skin}} \cdot N \cdot u_p \cdot I_0 \cdot p(t). \tag{32} \end{equation}$

Так как проекция является ортогональной относительно зеркального отражения ${(N \cdot u_s \cdot I_0 \cdot s(t))}$ , то ${ P_{{Chrom}} \cdot U_{{skin}} \cdot N \cdot \ u_s \cdot I_0 \cdot s(t)=0}$ , поэтому в {(32)} данный компонент исчезает.

Таким образом, мы получили два сигнала цветности {S(t)} , к которым далее применяется процедура альфа-тюнинга для устранения искажений, вызываемых изменением интенсивности светового потока из-за движений, то есть для устранения компонента ${1 \cdot i(t).}$

1.7. Метод POS

Наконец, мы обсудим State-of-the-art метод POS [5], который, как и CHROM, работает в нормализованном во времени RGB-пространстве, однако выполняет этапы проекции и альфа-тюнинга в обратном порядке.

1) Сначала устраняются искажения, вызываемые изменением интенсивности светового потока из-за движений, с помощью проекции в плоскость, ортогональную относительно направления интенсивности светового потока, то есть в направлении, ортогональном компоненту ${1 \cdot i(t)}$ . Данный компонент соответствует нормализованному оттенку кожи в дихроматической модели {(26)} . Поэтому получающая проекция – это проекция в плоскость, ортогональную нормализованному оттенку кожи. По этой причине метод POS и называется – метод проекции в плоскость, ортогональную оттенку кожи (Plane Orthogonal to Skin). Так как проекция является ортогональной относительно оттенка кожи, то нет необходимости выполнять поправку для источника света другого цвета. По этой причине в методе POS отсутствует этап умножения на стандартизированный вектор цвета кожи ${u_{skin}}$ .

При умножении на проекционную матрицу ${ P_{{POS}}}$ нормализованного во времени сигнала ${\tilde{C}_n(t) }$ получим согласно дихроматической модели {(26)} :

$\begin{equation} \tilde{C}_n(t) = C_n(t) - 1 = 1 \cdot i(t) + N \cdot u_s \cdot I_0 \cdot s(t) + N \cdot u_p \cdot I_0 \cdot p(t), \tag{26} \end{equation}$

$\begin{equation} S(t) = P_{{POS}} \cdot \tilde{C}_n(t) \approx P_{{POS}} \cdot N \cdot u_s \cdot I_0 \cdot s(t) + P_{{POS}} \cdot N \cdot u_p \cdot I_0 \cdot p(t). \tag{33} \end{equation}$

Так как проекция является ортогональной относительно интенсивности светового потока (или иначе говоря, нормализованного оттенка кожи) ${1 \cdot i(t)}$ , то ${ P_{POS} \cdot 1 \cdot i(t) = 0}$ . Поэтому данный компонент исчезает в {(33)} . Каким же образом мы можем выбрать проекционную матрицу ${ P_{POS}}$ ? Зависящий от времени компонент {i(t)} — это скаляр, поэтому он может изменить только длину вектора {1} , не влияя на его направление. Поэтому нам достаточно, чтобы ${ P_{POS} \cdot 1 = 0}$ . Нам также необходимо, чтобы оба компонента в ${ P_{POS}}$ — обозначаемые ${ P_{POS,1}}$ и ${ P_{POS,2}}$ — были ортогональны друг другу. Таким образом, необходимо, чтобы выполнялось два следующих условия:

$\begin{equation} \begin{aligned} &\begin{cases} \mathbf{P}_{{POS}} \cdot 1 = 0 \\ \mathbf{P}_{{POS},1} \cdot \mathbf{P}_{{POS},2} = 0 \end{cases} \end{aligned} \tag{34} \end{equation}$

Однако, каким же образом выбрать коэффициенты для проекционной матрицы? Существует много возможных вариантов. Для ответа на данный вопрос сделаем небольшое отступление.

Ранее в определенных стандартных условиях (галогеновая лампа в качестве источника света и камера UI-2220SE‑C для записи видео) было установлено, что в нормализованном во времени RGB‑пространстве вектор пульсового объема имеет стандартные значения [11]: ${u_{PBV}=[0.33, 0.77, 0.53]}$ . Данный вектор может использоваться напрямую для дальнейшего нахождения пульса, что лежит в основе другого алгоритма дистанционной фотоплетизмографии — PBV (Pulse Blood Volume). Такой подход обеспечивает высокую эффективность даже при существенных движениях человека. Однако его точность зависит от соответствия условий, при которых оценивается пульс, тем стандартным условиям, при которых был подсчитан данный вектор. В методе POS авторы использовали знание данного вектора для того, чтобы приблизительно оценить как выбранная проекционная матрица влияет на силу пульсового сигнала (рис. 5).

Рисунок 5. Нормализованные во времени RGB-сигналы проецируются в плоскость, ортогональную вектору (на рисунке – черная сплошная линия в трехмерном пространстве). Данный вектор указывает в направлении изменений интенсивности светового потока и при этом соответствует нормализованному оттенку кожи. В полученной плоскости показано распределение силы пульсового сигнала (красный / синий цвет соответствуют большой / меньшей силе сигнала). В зависимости от выбора проекционной матрицы проекция пульсового сигнала (вектора пульсового объема ) происходит в различные регионы плоскости. На рисунке приведены проекции для трех различных вариантов оси проекционной матрицы: , и . Их точечный продукт с позволяет оценить силу получаемого пульсового сигнала и соответствует , и . Правая часть рисунка показывает получаемый пульсовой сигнал. Очевидно, что проекция в направлении неудачна – полученный сигнал является зашумленным, что подтверждается низким по модулю значением силы пульсового сигнала [5].

Рисунок 5. Нормализованные во времени RGB-сигналы ${R_n(t), G_n(t), B_n(t)}$ проецируются в плоскость, ортогональную вектору {1}

(на рисунке – черная сплошная линия в трехмерном пространстве). Данный вектор указывает в направлении изменений интенсивности светового потока и при этом соответствует нормализованному оттенку кожи. В полученной плоскости показано распределение силы пульсового сигнала (красный / синий цвет соответствуют большой / меньшей силе сигнала). В зависимости от выбора проекционной матрицы проекция пульсового сигнала (вектора пульсового объема ${u_{PBV}=[0.33, 0.77, 0.53]}$ ) происходит в различные регионы плоскости. На рисунке приведены проекции ${ u_{PBV}}$ для трех различных вариантов оси проекционной матрицы: ${z_1=[-2, 1, 1]}$ , ${z_2=[1, -2, 1]}$ и ${z_3=[1, 1, -2]}$ . Их точечный продукт с ${ u_{PBV}}$ позволяет оценить силу получаемого пульсового сигнала и соответствует {−0,64}

. Правая часть рисунка показывает получаемый пульсовой сигнал. Очевидно, что проекция в направлении ${z_3}$ неудачна – полученный сигнал является зашумленным, что подтверждается низким по модулю значением силы пульсового сигнала {(−0.04)}

[5].

Оказалось, что сила получаемого пульсового сигнала зависит от того, в какую область плоскости, ортогональной оттенку кожи, происходит проекция пульсового сигнала. Поэтому проекционная матрица должна создаваться не произвольно, а с учетом указанных ранее физиологических особенностей — коэффициенты для RGB‑каналов берутся в порядке уменьшения пульсовой амплитуды. Напомним, что наибольшая амплитуда у G‑канала, а наименьшая — у R‑канала. Таким образом, авторы выбрали следующую проекционную матрицу

$\begin{equation} \mathbf{P}_{{POS}} = \begin{pmatrix} \mathbf{P}_{{POS},1} \\ \mathbf{P}_{{POS},2} \end{pmatrix} = \begin{pmatrix} 0 & 1 & -1 \\ -2 & 1 & 1 \end{pmatrix}. \tag{35} \end{equation}$

Мы можем убедиться, что оба условия в {(34)} действительно выполняются:

${P_{POS,1} \cdot 1=[0,1,-1]^T \cdot [1,1,1]=0 \cdot 1+1 \cdot 1-1 \cdot 1=0+1-1=0}$

${P_{POS,2} \cdot 1=[-2,1,1]^T \cdot [1,1,1]=-2 \cdot 1+1 \cdot 1+1 \cdot 1=-2+1+1=0}$

$\begin{equation} P_{POS,1} \cdot P_{POS,2} = [0,1,-1]^T \cdot [-2,1,1]=0 \cdot (-2)+1 \cdot 1-1 \cdot 1=0-1+1=0 \tag{36} \end{equation}$

При умножении на ${P_{POS}}$ полученные компоненты в {S(t)} эквивалентны следующим комбинациям RGB-каналов: ${S_1(t)=G_n-B_n, S_2(t)=-2R_n + G_n +B_n}$ . При этом оба компонента несут положительную пульсовую информацию, поэтому находятся в фазе.

2) Второй, и последний, этап POS — это альфа‑тюнинг для устранения зеркального отражения (напомним, что в методе CHROM альфа‑тюнинг используется для устранения искажений из‑за изменений интенсивности светового потока при движениях). Так как из‑за особенностей проекционной матрицы пульсовые компоненты в ${S_1}$ и ${S_2}$ находятся в фазе, то вместо их вычитания выполняется их сложение:

$\begin{equation} S = S_1 + \alpha S_2, \alpha = \frac{\sigma(S_1)} {\sigma(S_2)} \tag{37} \end{equation}$

Таким образом, когда доминирует пульсовой компонент, то ${S_2}$ и ${S_2}$ находятся в фазе и поэтому их сумма помогает усилить пульсовой сигнал. Если же доминируют находящиеся в противофазе искажения, вызванные зеркальным отражением, то разность их двух сигналов, позволяет устранить данные искажения.

Подводя итог, еще раз подчеркнем сходства и различия методов CHROM и POS в табл. 1. Два этапа — проекция и альфа‑тюнинг — выполняются в обратном порядке в данных методах, что и обуславливает их различия.

Таблица 1. Сравнительный анализ алгоритмов CHROM и POS

CHROM	POS
Временная нормализация для устранения влияния постоянного уровня интенсивности света ${(u_c \cdot I_0 \cdot c_0)}$	Временная нормализация для устранения влияния постоянного уровня интенсивности света ${(u_c \cdot I_0 \cdot c_0)}$
Проекция в направлении стандартизированного вектора цвета кожи под источником белого света	–
Проекция в плоскость, ортогональную зеркальному отражению, – позволяет убрать зеркальное отражение ${(u_s \cdot I_0 \cdot s(t))}$	Проекция в плоскость, ортогональную изменения интенсивности светового потока, –позволяет убрать искажения из-за изменения интенсивности светового потока из-за движений ${(1 \cdot i(t))}$
Альфа-тюнинг для устранения искажений из-за изменения интенсивности светового потока из-за движений ${(1 \cdot i(t))}$	Альфа-тюнинг для устранения зеркального отражения ${(u_s \cdot I_0 \cdot s(t))}$
Пульсовые компоненты находятся в противофазе	Пульсовые компоненты находятся в фазе

1.8. Метод OMIT

В заключение, мы рассмотрим метод OMIT, который был предложен в 2023 г. и основан на трансформации кадров с помощью ортогональной матрицы (Orthogonal Matrix Image Transformation). В данной работе авторы также разработали эффективный алгоритм для выбора области интереса, что позволяют улучшить результаты всех методов дистанционной фотоплетизмографии. Сам же метод OMIT является весьма простым с точки зрения мотивации и исполнения, однако несмотря на это является очень эффективным, в ряде случаев превосходя алгоритм POS.

Метод OMIT основан на разложении матрицы, содержащей средние значения RGB в каждом кадре видео, на ортогональные компоненты с помощью QR‑разложения. Матрица средних значений RGB-каналов в каждом кадре видео имеет форму ${n \times 3}$ , где {n} — число кадров, а {3} — средние значения трех RGB каналов. Данная матрица ${ A \in \mathbb{R}^{n \times 3} }$ может быть разложена на две другие матрицы — ${ Q \in \mathbb{R}^{n \times 3} }$ , которая содержит ортонормальный базис, и верхнюю треугольную матрицу ${ R \in \mathbb{R}^{3 \times 3} }$ , которая содержит коэффициенты, позволяющие представить оригинальную матрицу {A} в базисе {Q} . Таким образом,

$\begin{equation} A = Q R \tag{38}. \end{equation}$

Для эффективного разложения авторы используют метод отражений Хаусхолдера. В полученной матрице {Q} есть 3 столбца, которые образуют ортонормальный базис для исходной матрицы {A} . Ортонормальность означает, что векторы являются ортогональными друг другу и при этом их норма равна единице. Первый столбец ${q_1}$ в матрице {Q} показывает направление наиболее сильных изменений (наибольшей дисперсии) в исходном RGB пространстве. Данные изменения связаны в большинстве случаев с изменением цвета кожи при изменении интенсивности освещения из-за движений. Они также могут быть связаны с шумовым сигналом камеры или другими артефактами. Таким образом, означенное направление связано с факторами, которые затрудняют выявление пульсового сигнала. Для устранения влияния данных факторов выполняется проекция в направлении, ортогональном вектору ${q_1}$ .

Проекционная матрица ${P_{OMIT}}$ вычисляется следующим образом:

$\begin{equation} P_{OMIT} = I - q_1 q_2^T \tag{39}, \end{equation}$

где {I} — это единичная матрица размерностью ${n \times n}$ . Далее выполняется проекция исходной RGB-матрицы {A} и получается новая матрица {Y} :

$\begin{equation} Y = P_{OMIT} A \tag{40}. \end{equation}$

В полученной матрице {Y} первый столбец ${y_1}$ соответствует направлению наиболее сильных изменений, вызванных различным шумом, которые были устранены с помощью проекции. Тогда как второй столбец ${y_2}$ содержит искомый пульсовой сигнал после устранения шумового сигнала. Пульсовой сигнал ${(y_1)}$ после этого, как и в других методах, может быть дополнительно отфильтрован.

2. Технические аспекты дистанционной фотоплетизмографии

Описанные в прошлом разделе алгоритмы позволяют выделить пульсовой сигнал. Однако на их эффективность влияет целый ряд факторов, которые мы и обсудим в настоящей части.

2.1. Выбор области интереса

Первый этап при применении любого из алгоритмов дистанционной ФПГ — это выбор области интереса в видеозаписи [7]. Чаще всего для детекции лица используется алгоритм Виолы‑Джонса, который использует функцию Хаара и интегральное изображение для обнаружения и формирования прямоугольной рамки, ограничивающей лицо. Данный алгоритм отличается высокой скоростью, однако при его применении в области интереса остается часть фона. Более того, движения глаз, рта, блики от очков могут существенным образом влиять на подсчет пульса. Поэтому, исходя из стандартных пропорций человеческого лица, можно обрезать область интереса, исключив фон и глаза, и оставим только центральную часть лица или лоб. Более точный метод для детекции лица имплементирован в Mediapipe Face Mesh и позволяет детектировать 468 точек‑ориентиров на лице (рис. 6) [45]. Последние позволяют точным образом выделить лицо, убрав фон, убрать глаза и область рта или же выбрать отдельные участки, например часть лба или щек. Визуализация различных вариантов выбора области интереса приведена на рис. 7.

Рисунок 6. Mediapipe Face Mesh детектирует 468 точек-ориентиров на лице.

Рисунок 7. Сравнение методов выбора области интереса. Исходный кадр (а); прямоугольная рамка, ограничивающая лицо при применении алгоритма Виолы и Джонса (б); выбор центральной области рамки, чтобы убрать фон (в); закрытие области глаз для устранения влияния бликов (г); выделение лица с помощью точек ориентиров с помощью алгоритма Mediapipe Face Mesh (д); закрытие области глаз и рта с помощью точек ориентиров (е). Здесь и далее кадры взяты из датасета UBFC-rPPG для участников, которые подписали согласие на использование своих данных в статьях [37].

Выбор всего лица в качестве области интереса обеспечивает более стабильную оценку пульсового сигнала — за счет большей площади устраняется влияние шума в отдельных регионах. Однако при этом различные артефакты (очки, борода, усы и т. д.) могут затруднять точную оценку пульса. Более того, нужно отметить, что отдельные регионы лица отличаются друг от друга по интенсивности кровоснабжения и толщине эпидермиса, что напрямую влияет на процесс светоотражения. В связи с этим в литературе весьма популярен выбор лишь отдельных участков на лице. Сравнительный анализ показал, что наиболее перспективными являются области щек и лба, и именно данные регионы достаточно часто используются в качестве областей интереса в различных исследованиях [20].

Для выбора области интереса также возможно применение нейронных сетей, которые сегментируют изображение на отдельные части — фон, кожу, глаза, волосы и т. д. Так, в библиотеке pyVHR [31] используется модель для билатеральной сегментации BiSeNet [32] на основе ResNet18. Однако в ходе наших экспериментов при ее использовании качество сегментации оказалось низким. Более сложная модель SegFormer на основе архитектуры трансформера показала лучшие результаты [33]. Но обработка видео даже с использованием графического процессора в таком случае оказывается весьма медленной. Более того, модель оказалась неспособной убирать мелкие элементы, например бороду или усы, поэтому мы отказались от ее использования. Сравнение сегментации с помощью BiSeNet и SegFormer приведено на рис. 8.

Рисунок 8. Сегментация с помощью нейронных сетей. Исходный кадр (а). Сегментационная маска при использовании BiSeNet (б). Модель выделила фон, волосы, лицо, но оказалась неспособной на сегментацию очков и черт лица. Сегментационная маска при использовании SegFormer имеет значительно лучшее качество (в). Однако при ее применении к исходному кадру все еще сохранились борода и усы, что будет затруднять оценку пульсового сигнала (г).

Значительно более простым, но при этом более эффективным оказался подход на основе адаптивной оценки цвета кожи [34]. На первом этапе происходит выбор области лица, например с помощью алгоритма Виолы и Джонса, что позволяет убрать большое количество пикселей фона, оставив преимущественно пиксели кожи. Далее полученное изображение конвертируется в цветовое пространство HSV. В одном из каналов, происходит разбиение частоты пикселей различных цветов по гистограммам. Так как благодаря выбору области интереса большая часть пикселей фона была убрана, то доминирующим является цвет пикселей кожи, что и позволяет выбрать гистограмму с наибольшим числом пикселей ${hist_{max}}$ . После этого на основе эмпирически подобранного коэффициента ${\alpha}$ выбирается диапазон вокруг данной гистограммы с помощью следующей формулы:

${hist_{max} \pm (\alpha \cdot \frac { hist_{max} }{2})}$

Пиксели, имеющие цвет за пределами данного диапазона, не являются пикселями кожи и поэтому закрашиваются черным цветом. Данный подход отличается вычислительной простотой и позволяет эффективно убрать различные артефакты, затрудняющие оценку пульсового сигнала, — очки, волосы, бороду и усы. Результаты применения данного алгоритма приведены на рис. 9.

Рисунок 9 [34]. Применение метода гистограмм к различным каналам HSV пространства при различных значениях коэффициента ${\alpha}$ .

В ряде работ вместо выбора фиксированных регионов предлагается их динамическая оценка. Так, в [35] авторы предложили отслеживать 7 регионов, разделить каждый из них на небольшие квадраты, для каждого из полученных квадратов посчитать качество сигнала и затем найти пульсовой сигнал как среднее взвешенное всех сигналов, где вес выше у сигналов с лучшим качеством (рис. 10).

Рисунок 10 [35]. Отслеживание 7 регионов (а), их разделение на квадраты (б) и подсчет качества сигнала в каждом из квадратов (в).

Схожий подход был предложен и в [36], однако вместо отслеживания отдельных регионов выполнялось отслеживание всего лица. После оценки отношения сигнала к шуму для каждого из квадратов, выбирались лучшие из них и на их основе подсчитывался пульсовой сигнал (рис. 11).

Рисунок 11 [36]. Разделение кадров области интереса на квадраты (a), подсчет качества сигнала в каждом из квадратов (б) и выбор квадратов с наилучшим качеством.

В [37-38] авторы предложили использовать не фиксированное разбиение на квадраты, а на разделение на суперпиксели, отслеживаемые во времени, — темпоральные суперпиксели. Как и в других работах выбор оптимальных регионов выполнялся с помощью отношения сигнала к шуму (рис. 12).

Рисунок 12 [37]. Разделение кадров (а) на темпоральные суперпиксели (б) и оценка качества сигнала в каждом из квадратов них (в).

Авторы алгоритма OMIT предложили детальный подход для выбора области интереса, который позволил значительно улучшить эффективность всех алгоритмов дистанционной фотоплетизмографии [21]. На первом этапе определяется 85 точек‑ориентиров на лице. Они соединяются между собой, разделяя лицо на треугольники, которые затем проецируются в фиксированные координаты, соответствующие лицу человека во фронтальной проекции (рис. 13). Каждый кадр видео проецируется в данные фиксированные координаты, что позволяет измерять пульсовой сигнал в одних и тех же участках лица.

Рисунок 13 [21]. Определение точек ориентиров на лице (а), триангуляция по данным точкам (б) и проекция полученных треугольников в фиксированные координаты (в).

После проекции в фиксированные координаты производится разделение изображения на сравнительно крупные квадраты, в каждом из которых оценивается качество сигнала. Оценка пульса выполняется на основе квадратов с наилучшим сигналом (рис. 14).

Рисунок 14 [21]. В зависимости от положения лица в кадре и качества освещения выбирается 32 квадрата (сверху) или 20 квадратов (снизу).

Для оценки качества сигнала в каждом из регионов применяется следующий подход:

1) Проводится оценка дисперсии и исключаются регионы с нулевой дисперсией, как не несущие полезной информации.

2) Подсчитывается фрактальная размерность Катца — показатель, который оценивает степень иррегулярности сигнала и остроты пиков и характеризует насколько комплексным является характер сигнала. Далее находят отношение фрактальной размерности сигнала в одном регионе к фрактальной размерности глобального сигнала, полученного со всего лица, и выбираются регионы со значением >0,85 — это позволяет учитывать только те регионы, в которых сигнал имеют сопоставимые характеристики с глобальным сигналом. Таким образом, убираются регионы, несущие преимущественно шумовой сигнал.

3) Выполняется анализ детрендированных флуктуаций, который помогает оценить корреляцию между двумя нестационарными временными рядами. Данный метод позволяет проанализировать корреляцию между сигналом в отдельном регионе и глобальным регионом с помощью ‑экспоненты. Если ${\alpha=0,5}$ , то между временными рядами нет корреляции, если ${0,5< \alpha<1}$ — корреляция положительная, а если ${0< \alpha <0,5}$ , то корреляция отрицательная. Для дальнейшего анализы выбираются только регионы с положительной корреляцией.

После выбора регионов согласно означенным критериям, пульсовые сигналы из них суммируются во временном домене, позволяя получить итоговый пульсовой сигнал.

Наконец, в [22] авторы предложили оригинальный подход, основанный не на определении наилучших областей интереса, а на выборе оптимальных сигналов. Для этого они предложили отслеживать множество небольших регионов, определить в каждом из них пульсовой сигнал, а затем выполнить их спектральную кластеризацию, получив две группы. Сигналы с хорошим качеством имеют приблизительно одинаковый спектр и попадают в один кластер, тогда как сигналы с плохим качеством имеют большую внтуригрупповую (отличаются между собой) и межгрупповую (отличаются от сигналов в хорошем кластере) дисперсию. Итоговый пульсовой сигнал определяется на основе данных из хорошего кластера.

2.2. Применение фильтров

Одним из ключевых этапов является фильтрация полученного сигнала для устранения шума. При этом возможна как фильтрация RGB‑сигнала, так и полученного после применения одного из алгоритмов пульсового сигнала. Последний подход является более распространённым. Прежде всего используются классические фильтры для выбора частот в определенном диапазоне, соответствующем возможной частоте сердечных сокращений — от 40 до 240 ударов в минуту (0,75–3 Гц), а частоты ниже и выше данного диапазона исключаются. Чаще всего применяют фильтр Баттерворта, в отдельных работах — фильтра Чебышева 1 или 2 типа, фильтр Савицкого‑Голея, эллиптический фильтр, вейвлет‑фильтр и др., а также скользящий средний фильтр [9]. Сравнительный анализ указанных фильтров показал, что наиболее оптимальным является фильтр Чебышева 2 типа [9]. Для ЭКГ был предложен фильтр для устранения тренда [10], и он находит свое применение и в области дистанционной ФПГ. Результаты применения отдельных фильтров приведены на рис. 15.

Рисунок 15. Исходный пульсовой сигнал, полученный с помощью метода POS (a). Применение среднего скользящего фильтра для сглаживания сигнала (б). Применение фильтра для устранения тренда (в). Применение фильтра Чебышева 2 типа для сохранения частот в диапазоне 0,7-3 Гц (г).

Был также разработан ряд специальных фильтров, например, фильтр для выбора амплитуды [16]. Последний основан на том факте, относительная пульсовая амплитуда варьируется в определенном диапазоне, который может быть представлен как функция, зависимая от RGB‑каналов. В дальнейшем авторы предложили фильтр для фильтрации частот на основе искажений цветового сигнала [17], основанный на том факте, что пульсовой компонент и компоненты, связанные с изменением интенсивности и зеркальным отражением, имеют разные спектры отражения.

Наконец, существует ряд работ по применению методов машинного и глубокого обучения для фильтрации сигналов, например — использование метода опорных векторов [19] или нейронной сети долгой краткосрочной памяти для восстановления формы полученного пульсового сигнала [18].

Несмотря на большое число предложенных методов, сравнительно мало исследований посвящено сравнению эффективности различных фильтров и их комбинаций. В настоящей работе мы оценили эффективность ряда наиболее распространенных фильтров и их комбинаций для различных методов ФПГ.

2.3. Подсчет частоты сердечных сокращений

После получения пульсового сигнала проводят подсчет частоты сердечных сокращений (ЧСС) [7]. Наиболее распространенным является подход на основе спектрального анализа. Полученный сигнал конвертируется в частотный спектр с помощью быстрого преобразования Фурье или дискретного косинусного преобразования. Распределение спектральной плотности мощности (пример приведен на рис. 16) оценивается как функция частоты с помощью метода Велча в диапазоне от 0,7 до 3 Гц, что соответствует ЧСС от 40 до 180 ударов в минуту. Используемый диапазон в отдельных работах может немного различаться, например от 0,75 до 2,5 Гц (45 — 150 ударов в минуту). Частота с наибольшей мощностью {f} выбирается как соответствующая пульсовому сигналу и используется для подсчета ЧСС: ${ЧСС = 60 \cdot f}$ . Менее распространенным является поход на основе детекции пиков, соответствующих сокращениям сердца в полученном сигнале, и их подсчете.

Рисунок 16. Распределение спектральной плотности мощности для полученного пульсового сигнала (график голубого и оранжевого цвета). Отчетливо видны три доминантные частоты, соответствующие приблизительно 15, 75 и 600 ударам в минуту. После фильтрации частот в диапазоне от 0,75 до 2,5 Гц (от 45 до 150 ударов в минуту) остается только часть спектра (оранжевого цвета, ограничена вертикальными красными линиями), в которой наблюдается только одна доминантная частота, соответствующая 75 ударам в минуту.

2.4. Оценка результатов

Наиболее показательной метрикой является средняя абсолютная ошибка (MAE), показывающая абсолютную разницу между истинной ЧСС, определенной на основе ЭКГ или контактной ФПГ, и ЧСС по данной дистанционной ФПГ, усредненной по числу оцениваемых примеров: ${MAE = 1/N \cdot (|True HR - Estimated HR|)}$ . Во многих работах также применяется отношение сигнала к шуму для оценки информативности получаемого сигнала. Однако данная метрика, хотя и удобна для технического сравнения методов, не позволяет получить представление об их практической эффективности при оценке ЧСС. По этой причине мы сосредоточимся на использовании MAE.

Ключевым вопросом является методика оценки результатов. В одних работах для подсчета ЧСС используется все видео, а в других — видео разделяется на сегменты определенной длины, например по 5 или 10 секунд, и ЧСС определяется отдельно для каждого из сегментов, после чего метрика усредняется по всем сегментам. Более того, сегменты могут не пересекаться (например, 20-секундное видео можно разделить на 2 сегмента по 10 секунд), а могут идти с наложением (например с шагом в 1 секунду — в этом случае получится 11 сегментов). К сожалению, во многих работах авторы не указывают детали, что затрудняет возможность сравнения результатов [8]. Размер временного окна существенным образом влияет не только на оценку ЧСС с помощью дистанционной ФПГ, но и на истинную ЧСС, определяемую на основе ЭКГ или контактной ФПГ. Поэтому во всех случаях рекомендуется явно указывать данные параметры [15].

2.5. Альтернативные цветовые пространства

Для дистанционной ФПГ чаще всего используется RGB‑сигнал. Однако в ряде работ исследовались перспективы других цветовых пространств. Примеры трансформаций приведены на рис. 17. При сравнении 7 цветовых пространств — RGB, HSL, HSV, HIS, XYZ, YUV оказалось, что наиболее информативными были каналы Hue в HSL/HSV/HIS, Y в XYZ, U в YUV и G в RGB [23]. В другой работе при сравнении RGB, HSI, CIE Lab, YCrCb наиболее информативной оказалась комбинация Cr и Cb каналов в YCrCb [24]. Авторы также предложили модифицировать алгоритм POS, используя вместо комбинаций RGB сигналов, предложенных в оригинальной работе, Cr и Cb каналы. Трансформация из RGB в YCrCb пространство происходит следующим образом [25]:

$\begin{equation} \begin{aligned} \begin{pmatrix} Y \\ Cr \\ Cb \end{pmatrix} = \begin{pmatrix} 0.299 & 0.587 & 0.114 \\ -0.168 & -0.331 & 0.499 \\ 0.499 & -0.418 & -0.081 \end{pmatrix} \cdot \begin{pmatrix} R \\ G \\ B \end{pmatrix} \end{aligned} \end{equation}$

Поэтому в модифицированном POS оригинальная проекционная матрица была заменена на следующую:

${P = \begin{pmatrix} -0.168 & -0.331 & 0.499 \\ 0.499 & -0.418 & -0.081 \end{pmatrix} }$

Авторы отметили, что это повысило отношение сигнала к шуму в получаемом пульсовом сигнале, однако в ходе наших экспериментов абсолютная ошибка при использовании такого подхода оказалась большей по сравнению с оригинальным методом POS. В других работах было также отмечено преимущество использования HSI и YCrCb [26] и CIE Lab [27, 28] пространств по сравнению с RGB. Однако результаты являются противоречивыми. При непосредственном сравнении различных цветовых пространств наименьшая ошибка наблюдалась именно в RGB‑пространстве, тогда как использование HSI или YCrCb значительно ухудшало результаты [29]. В наших экспериментах цветовая трансформация в CIE Lab привела к некоторому улучшению результатов в датасете UBFC‑rPPG, однако для других датасетов это привело к увеличению ошибок.

Рисунок 17. Изображение в различных цветовых пространствах. Верхний ряд – RGB, CIE Lab, YCrCb. Нижний ряд – XYZ, HLS, HSV.

3. Экспериментальная часть и ее результаты

Настоящая работа была посвящена сравнению эффективности различных методов выбора области интереса и применения фильтров и их комбинаций для дистанционной фотоплетизмографии. Для анализа использовалось 3 датасета — UBFC‑rPPG (40 видео) [37], MCD‑rPPG (были выбраны 40 видео) и MMPD (было выбрано по одному видео для каждого из 33 участников) [43]. Каждое видео разделялось на непересекающиеся сегменты по 10 секунд, истинное значение ЧСС определялось на основе соответствующего сегмента контактной фотоплетизмограммы в датасете. Для подсчета ЧСС применялся спектральный анализ, а в качестве метрики использовалась средняя абсолютная ошибка.

Для выбора области интереса применялось несколько ранее описанных вариантов:

1) использование алгоритма Виолы и Джонса для получения области, содержащей лицо, и ее последующая обрезка для устранения краев, содержащих фон, а также закрытие области глаз для устранения влияния бликов;

2) использование Mediapipe Face Mesh для выбора всего лица за исключением глаз и рта;

3) использование Mediapipe Face Mesh для выбора области щек и лба;

4) использование алгоритма Виолы и Джонса для получения области, содержащей лицо, и применение адаптивной оценки цвета кожи с помощью гистограмм.

Третий вариант оказался наиболее эффективным. Сочетание третьего и четвертого вариантов, хотя и способствовало лучшей сегментации кадров, позволяя оставить только пиксели кожи, привело к незначительному ухудшению результатов.

Далее было проведено сравнение эффективности фильтра для устранения тренда, фильтра Баттерворта, фильтра Чебышева 2 типа и скользящего среднего фильтра [9] по отдельности, а также в комбинациях. Так как фильтры Баттерворта и Чебышева имеют схожую функцию, то их совместное применение не оценивалось. Таким образом было получено 12 возможных комбинаций фильтров, которые применялись совместно с алгоритмами GREEN, CHROM, POS, PBV, LGI и OMIT.

Использование оптимальной комбинации фильтров способно существенным образом улучшить эффективность дистанционной фотоплетизмографии. Лучшие результаты для каждого из алгоритмов, а также результаты без использования каких‑либо фильтров приведены в табл. 2. Отметим, что в датасете MMPD результаты значительно хуже из‑за сильного сжатия видео, что ведет к потере информации, затрудняя таким образом процесс извлечения пульсового сигнала.

Почти во всех случаях оптимальной комбинацией оказалось применение фильтра для устранения тренда и фильтра Чебышева 2 типа. Хотя данные фильтры давно известны, и фильтр Чебышева в сравнении с рядом других фильтров был показан как оптимальный [9], настоящий анализ показал, что они представляют собой оптимальную комбинацию.

Наиболее эффективным оказался метод POS, поэтому, чтобы детальнее показать влияние отдельных фильтров и их комбинаций приведем все результаты для данного метода в табл. 3. При этом ключевую роль играют частотные фильтры — их отсутствие (строки №9-12) сопровождается наихудшими результатами. Подтверждая данные литературы, отметим, что фильтр Чебышева 2-го (строки №1-4) типа эффективнее, чем более часто используемый фильтр Баттерворта (строки №5-8). Добавление фильтра для устранения тренда почти всегда ведет к улучшению результатов, тогда как скользящий средний фильтр в одних случаях показывает положительный, а в других случаях отрицательный эффект (например, при сравнении строк №1 и №3, №9 и №10, №11 и №12).

Для иллюстрации эффективности предложенной комбинации фильтров мы также приведем результаты из библиотеки rPPG‑Toolbox для дистанционной фотоплетизмографии [42]. В табл. 4 показано, что предложенная комбинация фильтров позволяет существенным образом улучшить результаты для всех алгоритмов дистанционной фотоплетизмографии.

Помимо алгоритмов дистанционной фотоплетизмографии, основанных на классических методах обработки сигналов, существуют также решения на основе глубокого обучения. Применение нейронных сетей для анализа видео позволяет добиться значительно более высокой точности. Однако серьезной проблемой является нестабильность получаемых результатов — модель, обученная на одном датасете может показывать существенно худшие метрики при тестировании на других наборах данных (сравнение результатов приведено в библиотеке rPPG‑Toolbox [42]). Ключевая причина — это, вероятно, небольшой размер датасетов для дистанционной фотоплетизмографии, что способствует сильному переобучению. Хотя в дальнейшем модели глубокого обучения могут оказаться более перспективными, в настоящий момент классические методы обработки сигналов благодаря своей устойчивости представляются более предпочтительными.

В заключение, отметим, что дистанционная фотоплетизмография — это активно развивающееся направление, которое имеет большие перспективы для использования в телемедицине, бесконтактном мониторинге жизненно важных показателей и в качестве скринингового метода диагностики благодаря простоте и удобству применения в сочетании с высокой точностью. Предложенная в настоящей работе комбинация фильтров, отличаясь простотой, может существенным образом улучшить работу алгоритмов извлечения пульсового сигнала и, таким образом, рекомендована для широкого применения с целью повышения эффективности методик дистанционной фотоплетизмографии.

Библиографический список

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CRYPTO SCAM RECOVERY SUCCESSFUL – A TESTIMONIAL OF LOST PASSWORD TO YOUR DIGITAL WALLET BACK. My name is Robert Alfred, Am from Australia. I’m sharing my experience in the hope that it helps others who have been victims of crypto scams. A few months ago, I fell victim to a fraudulent crypto investment scheme linked to a broker company. I had invested heavily during a time when Bitcoin prices were rising, thinking it was a good opportunity. Unfortunately, I was scammed out of $120,000 AUD and the broker denied me access to my digital wallet and assets. It was a devastating experience that caused many sleepless nights. Crypto scams are increasingly common and often involve fake trading platforms, phishing attacks, and misleading investment opportunities. In my desperation, a friend from the crypto community recommended Capital Crypto Recovery Service, known for helping victims recover lost or stolen funds. After doing some research and reading multiple positive reviews, I reached out to Capital Crypto Recovery. I provided all the necessary information—wallet addresses, transaction history, and communication logs. Their expert team responded immediately and began investigating. Using advanced blockchain tracking techniques, they were able to trace the stolen Dogecoin, identify the scammer’s wallet, and coordinate with relevant authorities to freeze the funds before they could be moved. Incredibly, within 24 hours, Capital Crypto Recovery successfully recovered the majority of my stolen crypto assets. I was beyond relieved and truly grateful. Their professionalism, transparency, and constant communication throughout the process gave me hope during a very difficult time. If you’ve been a victim of a crypto scam, I highly recommend them with full confidence contacting: 📧 Email: [email protected] 📱 Telegram: @Capitalcryptorecover Contact: [email protected] 📞 Call/Text: +1 (336) 390-6684 🌐 Website: https://recovercapital.wixsite.com/capital-crypto-rec-1
14.09.25 17:48 robertalfred175

CRYPTO SCAM RECOVERY SUCCESSFUL – A TESTIMONIAL OF LOST PASSWORD TO YOUR DIGITAL WALLET BACK. My name is Robert Alfred, Am from Australia. I’m sharing my experience in the hope that it helps others who have been victims of crypto scams. A few months ago, I fell victim to a fraudulent crypto investment scheme linked to a broker company. I had invested heavily during a time when Bitcoin prices were rising, thinking it was a good opportunity. Unfortunately, I was scammed out of $120,000 AUD and the broker denied me access to my digital wallet and assets. It was a devastating experience that caused many sleepless nights. Crypto scams are increasingly common and often involve fake trading platforms, phishing attacks, and misleading investment opportunities. In my desperation, a friend from the crypto community recommended Capital Crypto Recovery Service, known for helping victims recover lost or stolen funds. After doing some research and reading multiple positive reviews, I reached out to Capital Crypto Recovery. I provided all the necessary information—wallet addresses, transaction history, and communication logs. Their expert team responded immediately and began investigating. Using advanced blockchain tracking techniques, they were able to trace the stolen Dogecoin, identify the scammer’s wallet, and coordinate with relevant authorities to freeze the funds before they could be moved. Incredibly, within 24 hours, Capital Crypto Recovery successfully recovered the majority of my stolen crypto assets. I was beyond relieved and truly grateful. Their professionalism, transparency, and constant communication throughout the process gave me hope during a very difficult time. If you’ve been a victim of a crypto scam, I highly recommend them with full confidence contacting: 📧 Email: [email protected] 📱 Telegram: @Capitalcryptorecover Contact: [email protected] 📞 Call/Text: +1 (336) 390-6684 🌐 Website: https://recovercapital.wixsite.com/capital-crypto-rec-1
14.09.25 20:49 Clinton

I know firsthand how devastating it feels to lose money to a scam. When it happened to me, I was left frustrated, hopeless, and unsure where to turn. Complaining to apps about being scammed on their platforms didn’t change anything it felt like no one cared. But through a friend’s advice, I connected with a recovery professional who gave me real hope. With their help, I was able to get my funds back, something I thought was impossible. I’m sharing this because I don’t want anyone else to feel as lost as I once did. Whether you’ve been scammed through crypto platforms, dating scams, real-estate or mortgage fraud, or even fake ICOs, please know there’s still a way forward. If you’ve lost money, reach out to ([email protected]) or (WhatsApp) at (+)44 7366445035 for consultation and recovery services.
14.09.25 22:16 Berrysmith

I recently recovered a large sum of digital assets. Sylvester Bryant, reachable at Yt7cracker@gmail. com, helped me reclaim 720,000 in Ethereum. The entire experience was excellent. I highly recommend Mr. Sylvester. He assists those dealing with lost or stolen funds. His skill in getting back money from scams is outstanding. Scammers cause huge stress and financial pain. Mr. Bryant offers a crucial service. He provides a way to possibly recover stolen funds. His professional manner built trust. If you lost money to scams, contact him. He is also on WhatsApp at +1 512 577 7957. This makes it easy to discuss your case. Recovering this amount was difficult. Mr. Bryant showed deep knowledge of the technical work. His commitment to solving these problems is clear. Seek his help for lost crypto or other digital assets. This is a major concern for many. Expert aid can greatly improve outcomes.
15.09.25 10:25 aliceforemanlaw

I got back a lot of digital money recently. Sylvester Bryant helped me recover 120,000 in Ethereum. You can reach him at Yt7cracker@gmail. com. It was a great experience overall. I really suggest Mr. Sylvester. He helps people who lost money. He is great at getting money back from scams. Scammers cause a lot of stress and hurt. Mr. Bryant offers an important service. He can help you get back stolen funds. He was very professional and earned my trust. Contact him if you lost money to scams. He is also on WhatsApp at +1 512 577 7957. This makes it easy to talk about your situation. Getting this amount back was tough. Mr. Bryant knew a lot about the technical parts. His drive to fix these issues is clear. Get his help if you lost crypto or other digital items. Many people worry about this. Getting expert help can really make a difference.
15.09.25 12:49 robertalfred175

CRYPTO SCAM RECOVERY SUCCESSFUL – A TESTIMONIAL OF LOST PASSWORD TO YOUR DIGITAL WALLET BACK. My name is Robert Alfred, Am from Australia. I’m sharing my experience in the hope that it helps others who have been victims of crypto scams. A few months ago, I fell victim to a fraudulent crypto investment scheme linked to a broker company. I had invested heavily during a time when Bitcoin prices were rising, thinking it was a good opportunity. Unfortunately, I was scammed out of $120,000 AUD and the broker denied me access to my digital wallet and assets. It was a devastating experience that caused many sleepless nights. Crypto scams are increasingly common and often involve fake trading platforms, phishing attacks, and misleading investment opportunities. In my desperation, a friend from the crypto community recommended Capital Crypto Recovery Service, known for helping victims recover lost or stolen funds. After doing some research and reading multiple positive reviews, I reached out to Capital Crypto Recovery. I provided all the necessary information—wallet addresses, transaction history, and communication logs. Their expert team responded immediately and began investigating. Using advanced blockchain tracking techniques, they were able to trace the stolen Dogecoin, identify the scammer’s wallet, and coordinate with relevant authorities to freeze the funds before they could be moved. Incredibly, within 24 hours, Capital Crypto Recovery successfully recovered the majority of my stolen crypto assets. I was beyond relieved and truly grateful. Their professionalism, transparency, and constant communication throughout the process gave me hope during a very difficult time. If you’ve been a victim of a crypto scam, I highly recommend them with full confidence contacting: 📧 Email: [email protected] 📱 Telegram: @Capitalcryptorecover Contact: [email protected] 📞 Call/Text: +1 (336) 390-6684 🌐 Website: https://recovercapital.wixsite.com/capital-crypto-rec-1
15.09.25 12:49 robertalfred175

CRYPTO SCAM RECOVERY SUCCESSFUL – A TESTIMONIAL OF LOST PASSWORD TO YOUR DIGITAL WALLET BACK. My name is Robert Alfred, Am from Australia. I’m sharing my experience in the hope that it helps others who have been victims of crypto scams. A few months ago, I fell victim to a fraudulent crypto investment scheme linked to a broker company. I had invested heavily during a time when Bitcoin prices were rising, thinking it was a good opportunity. Unfortunately, I was scammed out of $120,000 AUD and the broker denied me access to my digital wallet and assets. It was a devastating experience that caused many sleepless nights. Crypto scams are increasingly common and often involve fake trading platforms, phishing attacks, and misleading investment opportunities. In my desperation, a friend from the crypto community recommended Capital Crypto Recovery Service, known for helping victims recover lost or stolen funds. After doing some research and reading multiple positive reviews, I reached out to Capital Crypto Recovery. I provided all the necessary information—wallet addresses, transaction history, and communication logs. Their expert team responded immediately and began investigating. Using advanced blockchain tracking techniques, they were able to trace the stolen Dogecoin, identify the scammer’s wallet, and coordinate with relevant authorities to freeze the funds before they could be moved. Incredibly, within 24 hours, Capital Crypto Recovery successfully recovered the majority of my stolen crypto assets. I was beyond relieved and truly grateful. Their professionalism, transparency, and constant communication throughout the process gave me hope during a very difficult time. If you’ve been a victim of a crypto scam, I highly recommend them with full confidence contacting: 📧 Email: [email protected] 📱 Telegram: @Capitalcryptorecover Contact: [email protected] 📞 Call/Text: +1 (336) 390-6684 🌐 Website: https://recovercapital.wixsite.com/capital-crypto-rec-1
15.09.25 12:49 robertalfred175

CRYPTO SCAM RECOVERY SUCCESSFUL – A TESTIMONIAL OF LOST PASSWORD TO YOUR DIGITAL WALLET BACK. My name is Robert Alfred, Am from Australia. I’m sharing my experience in the hope that it helps others who have been victims of crypto scams. A few months ago, I fell victim to a fraudulent crypto investment scheme linked to a broker company. I had invested heavily during a time when Bitcoin prices were rising, thinking it was a good opportunity. Unfortunately, I was scammed out of $120,000 AUD and the broker denied me access to my digital wallet and assets. It was a devastating experience that caused many sleepless nights. Crypto scams are increasingly common and often involve fake trading platforms, phishing attacks, and misleading investment opportunities. In my desperation, a friend from the crypto community recommended Capital Crypto Recovery Service, known for helping victims recover lost or stolen funds. After doing some research and reading multiple positive reviews, I reached out to Capital Crypto Recovery. I provided all the necessary information—wallet addresses, transaction history, and communication logs. Their expert team responded immediately and began investigating. Using advanced blockchain tracking techniques, they were able to trace the stolen Dogecoin, identify the scammer’s wallet, and coordinate with relevant authorities to freeze the funds before they could be moved. Incredibly, within 24 hours, Capital Crypto Recovery successfully recovered the majority of my stolen crypto assets. I was beyond relieved and truly grateful. Their professionalism, transparency, and constant communication throughout the process gave me hope during a very difficult time. If you’ve been a victim of a crypto scam, I highly recommend them with full confidence contacting: 📧 Email: [email protected] 📱 Telegram: @Capitalcryptorecover Contact: [email protected] 📞 Call/Text: +1 (336) 390-6684 🌐 Website: https://recovercapital.wixsite.com/capital-crypto-rec-1
16.09.25 12:25 aliceforemanlaw

Sylvester Bryant helped me recover 120,000 in Ethereum. You can reach him at Yt7cracker@gmail. com. It was a great experience overall. I really suggest Mr. Sylvester. He helps people who lost money. He is great at getting money back from scams. Scammers cause a lot of stress and hurt. Mr. Bryant offers an important service. He can help you get back stolen funds. He was very professional and earned my trust. Contact him if you lost money to scams. He is also on WhatsApp at +1 512 577 7957. This makes it easy to talk about your situation. Getting this amount back was tough. Mr. Bryant knew a lot about the technical parts. His drive to fix these issues is clear. Get his help if you lost crypto or other digital items. Many people worry about this. Getting expert help can really make a difference.
16.09.25 12:26 aliceforemanlaw

Sylvester Bryant helped me recover 120,000 in Ethereum. You can reach him at Yt7cracker@gmail. com. It was a great experience overall. I really suggest Mr. Sylvester. He helps people who lost money. He is great at getting money back from scams. Scammers cause a lot of stress and hurt. Mr. Bryant offers an important service. He can help you get back stolen funds. He was very professional and earned my trust. Contact him if you lost money to scams. He is also on WhatsApp at +1 512 577 7957. This makes it easy to talk about your situation. Getting this amount back was tough. Mr. Bryant knew a lot about the technical parts. His drive to fix these issues is clear. Get his help if you lost crypto or other digital items. Many people worry about this. Getting expert help can really make a difference.
16.09.25 13:25 marcushenderson624

Bitcoin Recovery Testimonial After falling victim to a cryptocurrency scam group, I lost $354,000 worth of USDT. I thought all hope was lost from the experience of losing my hard-earned money to scammers. I was devastated and believed there was no way to recover my funds. Fortunately, I started searching for help to recover my stolen funds and I came across a lot of testimonials online about Capital Crypto Recovery, an agent who helps in recovery of lost bitcoin funds, I contacted Capital Crypto Recover Service, and with their expertise, they successfully traced and recovered my stolen assets. Their team was professional, kept me updated throughout the process, and demonstrated a deep understanding of blockchain transactions and recovery protocols. They are trusted and very reliable with a 100% successful rate record Recovery bitcoin, I’m grateful for their help and highly recommend their services to anyone seeking assistance with lost crypto. Contact: [email protected] Phone CALL/Text Number: +1 (336) 390-6684 Email: [email protected] Website: https://recovercapital.wixsite.com/capital-crypto-rec-1
16.09.25 13:25 marcushenderson624

Bitcoin Recovery Testimonial After falling victim to a cryptocurrency scam group, I lost $354,000 worth of USDT. I thought all hope was lost from the experience of losing my hard-earned money to scammers. I was devastated and believed there was no way to recover my funds. Fortunately, I started searching for help to recover my stolen funds and I came across a lot of testimonials online about Capital Crypto Recovery, an agent who helps in recovery of lost bitcoin funds, I contacted Capital Crypto Recover Service, and with their expertise, they successfully traced and recovered my stolen assets. Their team was professional, kept me updated throughout the process, and demonstrated a deep understanding of blockchain transactions and recovery protocols. They are trusted and very reliable with a 100% successful rate record Recovery bitcoin, I’m grateful for their help and highly recommend their services to anyone seeking assistance with lost crypto. Contact: [email protected] Phone CALL/Text Number: +1 (336) 390-6684 Email: [email protected] Website: https://recovercapital.wixsite.com/capital-crypto-rec-1
17.09.25 02:56 peju1213

It can be very concerning to lose access to your USDT (Tether) wallet. It could potentially result in permanent loss of significant funds. You may have misplaced your private keys. Perhaps you unintentionally erased something, or your security was breached. It seems hopeless when you are unable to access your USDT. However, it doesn't have to stop there. There are methods for recovering your lost USDT. During difficult circumstances, professional assistance and wise recuperation techniques can give you hope. get in touch with Marie ([email protected] and +1 7127594675) on WhatsApp.
17.09.25 11:16 [email protected]

Sylvester Bryant helped me recover $510,000 in Ethereum, and I highly recommend his services. He specializes in helping people recover funds lost to scams. Scammers can cause significant stress, but Mr. Bryant's professionalism and expertise in the technical aspects of recovery earned my trust. If you've lost money through scams, you can reach him at [ yt7cracker@gmail. com ] or on WhatsApp at +1 512 577 7957. His dedication to helping people get their stolen funds back is clear, and his support made a huge difference in my case.
17.09.25 11:16 [email protected]

Sylvester Bryant helped me recover $510,000 in Ethereum, and I highly recommend his services. He specializes in helping people recover funds lost to scams. Scammers can cause significant stress, but Mr. Bryant's professionalism and expertise in the technical aspects of recovery earned my trust. If you've lost money through scams, you can reach him at [ yt7cracker@gmail. com ] or on WhatsApp at +1 512 577 7957. His dedication to helping people get their stolen funds back is clear, and his support made a huge difference in my case.
17.09.25 23:50 marcushenderson624

Bitcoin Recovery Testimonial After falling victim to a cryptocurrency scam group, I lost $354,000 worth of USDT. I thought all hope was lost from the experience of losing my hard-earned money to scammers. I was devastated and believed there was no way to recover my funds. Fortunately, I started searching for help to recover my stolen funds and I came across a lot of testimonials online about Capital Crypto Recovery, an agent who helps in recovery of lost bitcoin funds, I contacted Capital Crypto Recover Service, and with their expertise, they successfully traced and recovered my stolen assets. Their team was professional, kept me updated throughout the process, and demonstrated a deep understanding of blockchain transactions and recovery protocols. They are trusted and very reliable with a 100% successful rate record Recovery bitcoin, I’m grateful for their help and highly recommend their services to anyone seeking assistance with lost crypto. Contact: [email protected] Phone CALL/Text Number: +1 (336) 390-6684 Email: [email protected] Website: https://recovercapital.wixsite.com/capital-crypto-rec-1
17.09.25 23:50 marcushenderson624

Bitcoin Recovery Testimonial After falling victim to a cryptocurrency scam group, I lost $354,000 worth of USDT. I thought all hope was lost from the experience of losing my hard-earned money to scammers. I was devastated and believed there was no way to recover my funds. Fortunately, I started searching for help to recover my stolen funds and I came across a lot of testimonials online about Capital Crypto Recovery, an agent who helps in recovery of lost bitcoin funds, I contacted Capital Crypto Recover Service, and with their expertise, they successfully traced and recovered my stolen assets. Their team was professional, kept me updated throughout the process, and demonstrated a deep understanding of blockchain transactions and recovery protocols. They are trusted and very reliable with a 100% successful rate record Recovery bitcoin, I’m grateful for their help and highly recommend their services to anyone seeking assistance with lost crypto. Contact: [email protected] Phone CALL/Text Number: +1 (336) 390-6684 Email: [email protected] Website: https://recovercapital.wixsite.com/capital-crypto-rec-1
17.09.25 23:50 marcushenderson624

Bitcoin Recovery Testimonial After falling victim to a cryptocurrency scam group, I lost $354,000 worth of USDT. I thought all hope was lost from the experience of losing my hard-earned money to scammers. I was devastated and believed there was no way to recover my funds. Fortunately, I started searching for help to recover my stolen funds and I came across a lot of testimonials online about Capital Crypto Recovery, an agent who helps in recovery of lost bitcoin funds, I contacted Capital Crypto Recover Service, and with their expertise, they successfully traced and recovered my stolen assets. Their team was professional, kept me updated throughout the process, and demonstrated a deep understanding of blockchain transactions and recovery protocols. They are trusted and very reliable with a 100% successful rate record Recovery bitcoin, I’m grateful for their help and highly recommend their services to anyone seeking assistance with lost crypto. Contact: [email protected] Phone CALL/Text Number: +1 (336) 390-6684 Email: [email protected] Website: https://recovercapital.wixsite.com/capital-crypto-rec-1
18.09.25 11:55 Mundo

Sylvester Bryant recovered £400,000 in Ethereum for me. I strongly advise using his services. He focuses on retrieving money lost to fraudulent schemes. Scams cause immense worry. Mr. Bryant's expert knowledge and calm approach in getting funds back reassured me. If you have lost money to scams, contact him via email at [email protected]. You can also reach him on WhatsApp at +1 512 577 7957. He is committed to helping people recover their stolen assets. His support was invaluable in my situation.
18.09.25 11:55 Mundo

Sylvester Bryant recovered £400,000 in Ethereum for me. I strongly advise using his services. He focuses on retrieving money lost to fraudulent schemes. Scams cause immense worry. Mr. Bryant's expert knowledge and calm approach in getting funds back reassured me. If you have lost money to scams, contact him via email at [email protected]. You can also reach him on WhatsApp at +1 512 577 7957. He is committed to helping people recover their stolen assets. His support was invaluable in my situation.
18.09.25 12:22 wendytaylor015

My name is Wendy Taylor, I'm from Los Angeles, i want to announce to you Viewer how Capital Crypto Recover help me to restore my Lost Bitcoin, I invested with a Crypto broker without proper research to know what I was hoarding my hard-earned money into scammers, i lost access to my crypto wallet or had your funds stolen? Don’t worry Capital Crypto Recover is here to help you recover your cryptocurrency with cutting-edge technical expertise, With years of experience in the crypto world, Capital Crypto Recover employs the best latest tools and ethical hacking techniques to help you recover lost assets, unlock hacked accounts, Whether it’s a forgotten password, Capital Crypto Recover has the expertise to help you get your crypto back. a security company service that has a 100% success rate in the recovery of crypto assets, i lost wallet and hacked accounts. I provided them the information they requested and they began their investigation. To my surprise, Capital Crypto Recover was able to trace and recover my crypto assets successfully within 24hours. Thank you for your service in helping me recover my $647,734 worth of crypto funds and I highly recommend their recovery services, they are reliable and a trusted company to any individuals looking to recover lost money. Contact email [email protected] OR Telegram @Capitalcryptorecover Call/Text Number +1 (336)390-6684 his contact: [email protected] His website: https://recovercapital.wixsite.com/capital-crypto-rec-1
18.09.25 12:22 wendytaylor015

My name is Wendy Taylor, I'm from Los Angeles, i want to announce to you Viewer how Capital Crypto Recover help me to restore my Lost Bitcoin, I invested with a Crypto broker without proper research to know what I was hoarding my hard-earned money into scammers, i lost access to my crypto wallet or had your funds stolen? Don’t worry Capital Crypto Recover is here to help you recover your cryptocurrency with cutting-edge technical expertise, With years of experience in the crypto world, Capital Crypto Recover employs the best latest tools and ethical hacking techniques to help you recover lost assets, unlock hacked accounts, Whether it’s a forgotten password, Capital Crypto Recover has the expertise to help you get your crypto back. a security company service that has a 100% success rate in the recovery of crypto assets, i lost wallet and hacked accounts. I provided them the information they requested and they began their investigation. To my surprise, Capital Crypto Recover was able to trace and recover my crypto assets successfully within 24hours. Thank you for your service in helping me recover my $647,734 worth of crypto funds and I highly recommend their recovery services, they are reliable and a trusted company to any individuals looking to recover lost money. Contact email [email protected] OR Telegram @Capitalcryptorecover Call/Text Number +1 (336)390-6684 his contact: [email protected] His website: https://recovercapital.wixsite.com/capital-crypto-rec-1
18.09.25 13:04 Mundo

Sylvester Bryant recovered £400,000 in Ethereum for me. I strongly advise using his services. He focuses on retrieving money lost to fraudulent schemes. Scams cause immense worry. Mr. Bryant's expert knowledge and calm approach in getting funds back reassured me. If you have lost money to scams, contact him via email at [email protected]. You can also reach him on WhatsApp at +1 512 577 7957. He is committed to helping people recover their stolen assets. His support was invaluable in my situation.
18.09.25 16:46 carolinehudso83

I noticed a lot of online recommendations, and it’s clear that some of them are bad eggs that will just make уour mуsterу worse. I can onlу suggest one, and if уou need assistance getting back the moneу уou lost to scammers, уou can contact them bу email at: [email protected] Whats app or text +1 518 468 2985 Website https://bestrecoveryagent.com/
19.09.25 00:54 frank2025

Anthony davies played a crucial role in successfully recovering my stolen USDT, which was valued at more than $300,000. His expertise and dedication made the recovery process smooth and efficient. Throughout the entire time, he demonstrated himself to be a reliable recovery agent. His professionalism and commitment to his clients are evident in the results he achieves. If you find yourself in a similar situation or need assistance, he is available for contact. You can reach anthony through email at (anthonydaviestech AT gmail dot com). Alternatively, he is also accessible via telegram at anthonydavies01. Reaching out to him could be the first step toward recovering your lost assets
19.09.25 10:02 faithlawrence

Sylvester Bryant recovered £400,000 in Ethereum for me. I strongly advise using his services. He focuses on retrieving money lost to fraudulent schemes. Scams cause immense worry. Mr. Bryant's expert knowledge and calm approach in getting funds back reassured me. If you have lost money to scams, contact him via email at [email protected]. You can also reach him on WhatsApp at +1 512 577 7957. He is committed to helping people recover their stolen assets. His support was invaluable in my situation.
19.09.25 10:02 faithlawrence

Sylvester Bryant recovered £400,000 in Ethereum for me. I strongly advise using his services. He focuses on retrieving money lost to fraudulent schemes. Scams cause immense worry. Mr. Bryant's expert knowledge and calm approach in getting funds back reassured me. If you have lost money to scams, contact him via email at [email protected]. You can also reach him on WhatsApp at +1 512 577 7957. He is committed to helping people recover their stolen assets. His support was invaluable in my situation.
19.09.25 15:27 tonykith01477

There are not many reviews about free crypto recovery fixed but the ones that exist are mostly positive. I have no idea how that is possible, but it is clear that they are fabricated. However, there are also negative reviews – and I highly recommend paying attention to them. These are real people describing their unfortunate experiences with this scam. It’s the same story as always – fraudsters create a fake website to con people out of money. Nothing new but look no more and contact FASTRECOVERYAGENT These types of scams are everywhere. If you have already lost money to scammers i mean any type be it sending to scammers account , or if you have a case about stolen bitcoin , usdt, or any type of cryptocurrency whatsoever just reach out to www.fastrecoveryagent.com, i really owe this group of recovery expert because they saved me after bad investment with a fake broker, i literally owe them my life as they saved me from some bunch of scammers, but see how life is , i got every cent of my investment back with the profit , reach out to to them today and tell them from Mary because i promise them i will tell the whole world when the recovery is complete, and here i go after i got my recovered assets thats why im doing what i promised. do not fall for another scam. contact the,m today!!!!
19.09.25 17:12 wendytaylor015

My name is Wendy Taylor, I'm from Los Angeles, i want to announce to you Viewer how Capital Crypto Recover help me to restore my Lost Bitcoin, I invested with a Crypto broker without proper research to know what I was hoarding my hard-earned money into scammers, i lost access to my crypto wallet or had your funds stolen? Don’t worry Capital Crypto Recover is here to help you recover your cryptocurrency with cutting-edge technical expertise, With years of experience in the crypto world, Capital Crypto Recover employs the best latest tools and ethical hacking techniques to help you recover lost assets, unlock hacked accounts, Whether it’s a forgotten password, Capital Crypto Recover has the expertise to help you get your crypto back. a security company service that has a 100% success rate in the recovery of crypto assets, i lost wallet and hacked accounts. I provided them the information they requested and they began their investigation. To my surprise, Capital Crypto Recover was able to trace and recover my crypto assets successfully within 24hours. Thank you for your service in helping me recover my $647,734 worth of crypto funds and I highly recommend their recovery services, they are reliable and a trusted company to any individuals looking to recover lost money. Contact email [email protected] OR Telegram @Capitalcryptorecover Call/Text Number +1 (336)390-6684 his contact: [email protected] His website: https://recovercapital.wixsite.com/capital-crypto-rec-1
19.09.25 17:12 wendytaylor015

My name is Wendy Taylor, I'm from Los Angeles, i want to announce to you Viewer how Capital Crypto Recover help me to restore my Lost Bitcoin, I invested with a Crypto broker without proper research to know what I was hoarding my hard-earned money into scammers, i lost access to my crypto wallet or had your funds stolen? Don’t worry Capital Crypto Recover is here to help you recover your cryptocurrency with cutting-edge technical expertise, With years of experience in the crypto world, Capital Crypto Recover employs the best latest tools and ethical hacking techniques to help you recover lost assets, unlock hacked accounts, Whether it’s a forgotten password, Capital Crypto Recover has the expertise to help you get your crypto back. a security company service that has a 100% success rate in the recovery of crypto assets, i lost wallet and hacked accounts. I provided them the information they requested and they began their investigation. To my surprise, Capital Crypto Recover was able to trace and recover my crypto assets successfully within 24hours. Thank you for your service in helping me recover my $647,734 worth of crypto funds and I highly recommend their recovery services, they are reliable and a trusted company to any individuals looking to recover lost money. Contact email [email protected] OR Telegram @Capitalcryptorecover Call/Text Number +1 (336)390-6684 his contact: [email protected] His website: https://recovercapital.wixsite.com/capital-crypto-rec-1
20.09.25 15:05 faithlawrence

I can’t recommend Sylvester Bryant enough. He successfully recovered €210,000 in Ethereum for me after I had lost hope. His expertise in tracing and reclaiming funds from scams is truly remarkable. What stood out most was his calm, professional approach and deep technical knowledge, which gave me complete confidence throughout the process. If you’ve lost money to a scam, I strongly encourage you to reach out to him. You can contact him via email at [[email protected] ] or on WhatsApp at +1 512 577 7957. He is genuinely dedicated to helping people recover what they’ve lost, and his support has been invaluable to me.
20.09.25 15:53 blessing1198

It is distressing to lose USDT due to a bitcoin wallet hack. Although it is challenging, stolen USDT can be recovered. Taking prompt, wise action increases your chances. Marie can help you with reporting the theft, what to do right away, and USDT recovery. Contact her on WhatsApp at +1 7127594675, or email [email protected].
21.09.25 12:05 star1121

Consider this: In cryptocurrency, you see what appears to be a fantastic opportunity. After investing your hard-earned money, you see it disappear into the wallet of a con artist. Your bank account seems empty as rage and regret merge in this stomach punch. These days, cryptocurrency frauds are very common, however recovering your cryptocurrency from scammers is still possible. You can track down and possibly recover what you lost with shrewd actions. Marie can help; contact her at [email protected] and on WhatsApp at +1 7127594675.
23.09.25 03:23 robertalfred175

CRYPTO SCAM RECOVERY SUCCESSFUL – A TESTIMONIAL OF LOST PASSWORD TO YOUR DIGITAL WALLET BACK. My name is Robert Alfred, Am from Australia. I’m sharing my experience in the hope that it helps others who have been victims of crypto scams. A few months ago, I fell victim to a fraudulent crypto investment scheme linked to a broker company. I had invested heavily during a time when Bitcoin prices were rising, thinking it was a good opportunity. Unfortunately, I was scammed out of $120,000 AUD and the broker denied me access to my digital wallet and assets. It was a devastating experience that caused many sleepless nights. Crypto scams are increasingly common and often involve fake trading platforms, phishing attacks, and misleading investment opportunities. In my desperation, a friend from the crypto community recommended Capital Crypto Recovery Service, known for helping victims recover lost or stolen funds. After doing some research and reading multiple positive reviews, I reached out to Capital Crypto Recovery. I provided all the necessary information—wallet addresses, transaction history, and communication logs. Their expert team responded immediately and began investigating. Using advanced blockchain tracking techniques, they were able to trace the stolen Dogecoin, identify the scammer’s wallet, and coordinate with relevant authorities to freeze the funds before they could be moved. Incredibly, within 24 hours, Capital Crypto Recovery successfully recovered the majority of my stolen crypto assets. I was beyond relieved and truly grateful. Their professionalism, transparency, and constant communication throughout the process gave me hope during a very difficult time. If you’ve been a victim of a crypto scam, I highly recommend them with full confidence contacting: 📧 Email: [email protected] 📱 Telegram: @Capitalcryptorecover Contact: [email protected] 📞 Call/Text: +1 (336) 390-6684 🌐 Website: https://recovercapital.wixsite.com/capital-crypto-rec-1
23.09.25 03:23 robertalfred175

CRYPTO SCAM RECOVERY SUCCESSFUL – A TESTIMONIAL OF LOST PASSWORD TO YOUR DIGITAL WALLET BACK. My name is Robert Alfred, Am from Australia. I’m sharing my experience in the hope that it helps others who have been victims of crypto scams. A few months ago, I fell victim to a fraudulent crypto investment scheme linked to a broker company. I had invested heavily during a time when Bitcoin prices were rising, thinking it was a good opportunity. Unfortunately, I was scammed out of $120,000 AUD and the broker denied me access to my digital wallet and assets. It was a devastating experience that caused many sleepless nights. Crypto scams are increasingly common and often involve fake trading platforms, phishing attacks, and misleading investment opportunities. In my desperation, a friend from the crypto community recommended Capital Crypto Recovery Service, known for helping victims recover lost or stolen funds. After doing some research and reading multiple positive reviews, I reached out to Capital Crypto Recovery. I provided all the necessary information—wallet addresses, transaction history, and communication logs. Their expert team responded immediately and began investigating. Using advanced blockchain tracking techniques, they were able to trace the stolen Dogecoin, identify the scammer’s wallet, and coordinate with relevant authorities to freeze the funds before they could be moved. Incredibly, within 24 hours, Capital Crypto Recovery successfully recovered the majority of my stolen crypto assets. I was beyond relieved and truly grateful. Their professionalism, transparency, and constant communication throughout the process gave me hope during a very difficult time. If you’ve been a victim of a crypto scam, I highly recommend them with full confidence contacting: 📧 Email: [email protected] 📱 Telegram: @Capitalcryptorecover Contact: [email protected] 📞 Call/Text: +1 (336) 390-6684 🌐 Website: https://recovercapital.wixsite.com/capital-crypto-rec-1
23.09.25 03:23 robertalfred175

CRYPTO SCAM RECOVERY SUCCESSFUL – A TESTIMONIAL OF LOST PASSWORD TO YOUR DIGITAL WALLET BACK. My name is Robert Alfred, Am from Australia. I’m sharing my experience in the hope that it helps others who have been victims of crypto scams. A few months ago, I fell victim to a fraudulent crypto investment scheme linked to a broker company. I had invested heavily during a time when Bitcoin prices were rising, thinking it was a good opportunity. Unfortunately, I was scammed out of $120,000 AUD and the broker denied me access to my digital wallet and assets. It was a devastating experience that caused many sleepless nights. Crypto scams are increasingly common and often involve fake trading platforms, phishing attacks, and misleading investment opportunities. In my desperation, a friend from the crypto community recommended Capital Crypto Recovery Service, known for helping victims recover lost or stolen funds. After doing some research and reading multiple positive reviews, I reached out to Capital Crypto Recovery. I provided all the necessary information—wallet addresses, transaction history, and communication logs. Their expert team responded immediately and began investigating. Using advanced blockchain tracking techniques, they were able to trace the stolen Dogecoin, identify the scammer’s wallet, and coordinate with relevant authorities to freeze the funds before they could be moved. Incredibly, within 24 hours, Capital Crypto Recovery successfully recovered the majority of my stolen crypto assets. I was beyond relieved and truly grateful. Their professionalism, transparency, and constant communication throughout the process gave me hope during a very difficult time. If you’ve been a victim of a crypto scam, I highly recommend them with full confidence contacting: 📧 Email: [email protected] 📱 Telegram: @Capitalcryptorecover Contact: [email protected] 📞 Call/Text: +1 (336) 390-6684 🌐 Website: https://recovercapital.wixsite.com/capital-crypto-rec-1
23.09.25 03:54 robertalfred175

CRYPTO SCAM RECOVERY SUCCESSFUL – A TESTIMONIAL OF LOST PASSWORD TO YOUR DIGITAL WALLET BACK. My name is Robert Alfred, Am from Australia. I’m sharing my experience in the hope that it helps others who have been victims of crypto scams. A few months ago, I fell victim to a fraudulent crypto investment scheme linked to a broker company. I had invested heavily during a time when Bitcoin prices were rising, thinking it was a good opportunity. Unfortunately, I was scammed out of $120,000 AUD and the broker denied me access to my digital wallet and assets. It was a devastating experience that caused many sleepless nights. Crypto scams are increasingly common and often involve fake trading platforms, phishing attacks, and misleading investment opportunities. In my desperation, a friend from the crypto community recommended Capital Crypto Recovery Service, known for helping victims recover lost or stolen funds. After doing some research and reading multiple positive reviews, I reached out to Capital Crypto Recovery. I provided all the necessary information—wallet addresses, transaction history, and communication logs. Their expert team responded immediately and began investigating. Using advanced blockchain tracking techniques, they were able to trace the stolen Dogecoin, identify the scammer’s wallet, and coordinate with relevant authorities to freeze the funds before they could be moved. Incredibly, within 24 hours, Capital Crypto Recovery successfully recovered the majority of my stolen crypto assets. I was beyond relieved and truly grateful. Their professionalism, transparency, and constant communication throughout the process gave me hope during a very difficult time. If you’ve been a victim of a crypto scam, I highly recommend them with full confidence contacting: 📧 Email: [email protected] 📱 Telegram: @Capitalcryptorecover Contact: [email protected] 📞 Call/Text: +1 (336) 390-6684 🌐 Website: https://recovercapital.wixsite.com/capital-crypto-rec-1
23.09.25 14:45 Raymondkrisitina

Sylvester Bryant gets my full recommendation. He helped me get back €230,000 in Ethereum when I thought it was gone forever. His skills in tracking and retrieving scam-lost funds amaze me. I appreciated his steady, expert manner and strong tech know-how. That built my trust every step of the way. If a scam has taken your money, get in touch with him right away. Email him at yt7cracker@gmail. com or message on WhatsApp at +1 512 577 7957. He truly commits to aiding folks in regaining their assets. His help meant everything to me.
23.09.25 19:27 beverlyalex010

In 2022, I lost 1.5 ETH in what I thought was a promising Twitter investment. I reached out to the so-called brokers behind it, but they vanished and stopped replying. For years, I carried the heavy belief that my crypto was gone forever. Then, by chance, I discovered RecoveryFundProvider [email protected] WhatsApp at +44 736-644-5035 through a finance podcast. That moment changed everything. Their team didn’t lure me in with false promises or flashy guarantees. Instead, they explained their process clearly specializing in advanced blockchain tracing, smart contract forensics, and even transaction reversal in certain cases. Skeptical but hopeful, I allowed them to review my case. What followed was beyond my expectations. They dug deep into the blockchain ledger, followed the coin’s complex movements across multiple addresses, and even collaborated with global nodes to trace every trail. Two weeks later, I received an alert I never thought I’d see again: my crypto had been fully recovered and safely transferred back to me. I cried tears of relief. What sets RecoveryFundProvider apart isn’t just their cutting-edge expertise, but their unwavering ethics and dedication. They treat every client like more than just another case number even years after a loss. Today, I can confidently say they live up to their name, and I’m endlessly grateful.
23.09.25 22:38 Raymondkrisitina

Sylvester Bryant gets my full recommendation. He helped me get back €230,000 in Ethereum when I thought it was gone forever. His skills in tracking and retrieving scam-lost funds amaze me. I appreciated his steady, expert manner and strong tech know-how. That built my trust every step of the way. If a scam has taken your money, get in touch with him right away. Email him at yt7cracker@gmail. com or message on WhatsApp at +1 512 577 7957. He truly commits to aiding folks in regaining their assets. His help meant everything to me.
24.09.25 12:22 beverlyalex010

In 2022, I lost 1.5 ETH in what I thought was a promising Twitter investment. I reached out to the so-called brokers behind it, but they vanished and stopped replying. For years, I carried the heavy belief that my crypto was gone forever. Then, by chance, I discovered RecoveryFundProvider [email protected] WhatsApp at +44 736-644-5035 through a finance podcast. That moment changed everything. Their team didn’t lure me in with false promises or flashy guarantees. Instead, they explained their process clearly specializing in advanced blockchain tracing, smart contract forensics, and even transaction reversal in certain cases. Skeptical but hopeful, I allowed them to review my case. What followed was beyond my expectations. They dug deep into the blockchain ledger, followed the coin’s complex movements across multiple addresses, and even collaborated with global nodes to trace every trail. Two weeks later, I received an alert I never thought I’d see again: my crypto had been fully recovered and safely transferred back to me. I cried tears of relief. What sets RecoveryFundProvider apart isn’t just their cutting-edge expertise, but their unwavering ethics and dedication. They treat every client like more than just another case number even years after a loss. Today, I can confidently say they live up to their name, and I’m endlessly grateful.
24.09.25 15:50 michaeldavenport218

I was recently scammed out of $53,000 by a fraudulent Bitcoin investment scheme, which added significant stress to my already difficult health issues, as I was also facing cancer surgery expenses. Desperate to recover my funds, I spent hours researching and consulting other victims, which led me to discover the excellent reputation of Capital Crypto Recover, I came across a Google post It was only after spending many hours researching and asking other victims for advice that I discovered Capital Crypto Recovery’s stellar reputation. I decided to contact them because of their successful recovery record and encouraging client testimonials. I had no idea that this would be the pivotal moment in my fight against cryptocurrency theft. Thanks to their expert team, I was able to recover my lost cryptocurrency back. The process was intricate, but Capital Crypto Recovery's commitment to utilizing the latest technology ensured a successful outcome. I highly recommend their services to anyone who has fallen victim to cryptocurrency fraud. For assistance contact [email protected] and on Telegram OR Call Number +1 (336)390-6684 via email: [email protected] you can visit his website: https://recovercapital.wixsite.com/capital-crypto-rec-1
24.09.25 15:50 michaeldavenport218

I was recently scammed out of $53,000 by a fraudulent Bitcoin investment scheme, which added significant stress to my already difficult health issues, as I was also facing cancer surgery expenses. Desperate to recover my funds, I spent hours researching and consulting other victims, which led me to discover the excellent reputation of Capital Crypto Recover, I came across a Google post It was only after spending many hours researching and asking other victims for advice that I discovered Capital Crypto Recovery’s stellar reputation. I decided to contact them because of their successful recovery record and encouraging client testimonials. I had no idea that this would be the pivotal moment in my fight against cryptocurrency theft. Thanks to their expert team, I was able to recover my lost cryptocurrency back. The process was intricate, but Capital Crypto Recovery's commitment to utilizing the latest technology ensured a successful outcome. I highly recommend their services to anyone who has fallen victim to cryptocurrency fraud. For assistance contact [email protected] and on Telegram OR Call Number +1 (336)390-6684 via email: [email protected] you can visit his website: https://recovercapital.wixsite.com/capital-crypto-rec-1
24.09.25 15:50 michaeldavenport218

I was recently scammed out of $53,000 by a fraudulent Bitcoin investment scheme, which added significant stress to my already difficult health issues, as I was also facing cancer surgery expenses. Desperate to recover my funds, I spent hours researching and consulting other victims, which led me to discover the excellent reputation of Capital Crypto Recover, I came across a Google post It was only after spending many hours researching and asking other victims for advice that I discovered Capital Crypto Recovery’s stellar reputation. I decided to contact them because of their successful recovery record and encouraging client testimonials. I had no idea that this would be the pivotal moment in my fight against cryptocurrency theft. Thanks to their expert team, I was able to recover my lost cryptocurrency back. The process was intricate, but Capital Crypto Recovery's commitment to utilizing the latest technology ensured a successful outcome. I highly recommend their services to anyone who has fallen victim to cryptocurrency fraud. For assistance contact [email protected] and on Telegram OR Call Number +1 (336)390-6684 via email: [email protected] you can visit his website: https://recovercapital.wixsite.com/capital-crypto-rec-1
24.09.25 19:08 Raymondkrisitina

Sylvester Bryant gets my full recommendation. He helped me get back €230,000 in Ethereum when I thought it was gone forever. His skills in tracking and retrieving scam-lost funds amaze me. I appreciated his steady, expert manner and strong tech know-how. That built my trust every step of the way. If a scam has taken your money, get in touch with him right away. Email him at yt7cracker@gmail. com or message on WhatsApp at +1 512 577 7957. He truly commits to aiding folks in regaining their assets. His help meant everything to me.
24.09.25 19:50 Raymondkrisitina

Sylvester Bryant gets my full recommendation. He helped me get back €230,000 in Ethereum when I thought it was gone forever. His skills in tracking and retrieving scam-lost funds amaze me. I appreciated his steady, expert manner and strong tech know-how. That built my trust every step of the way. If a scam has taken your money, get in touch with him right away. Email him at yt7cracker@gmail. com or message on WhatsApp at +1 512 577 7957. He truly commits to aiding folks in regaining their assets. His help meant everything to me.
24.09.25 19:55 Athea5130

ETHICAL BITCOIN HACKER/ BEST WAY RECOVERY BITCOIN I believed I was completely lost. I was unable to withdraw money from my investment wallet after making a dubious investment, and until I discovered Best Way Hacker Company, no one could assist me in unfreezing it. This group handled my matter with attention and urgency. In a matter of days, they were able to retrieve my frozen investment and transfer it to a new wallet that I owned. They restored my hope in a big way. Best Way Hacker restored my money and my peace of mind, and for that I will always be grateful. Email.. [email protected] WhatsApp..+39-(350)-967-(1925)
24.09.25 19:56 Athea5130

ETHICAL BITCOIN HACKER/ BEST WAY RECOVERY BITCOIN I believed I was completely lost. I was unable to withdraw money from my investment wallet after making a dubious investment, and until I discovered Best Way Hacker Company, no one could assist me in unfreezing it. This group handled my matter with attention and urgency. In a matter of days, they were able to retrieve my frozen investment and transfer it to a new wallet that I owned. They restored my hope in a big way. Best Way Hacker restored my money and my peace of mind, and for that I will always be grateful. Email.. [email protected] WhatsApp..+39-(350)-967-(1925)
24.09.25 19:56 Athea5130

ETHICAL BITCOIN HACKER/ BEST WAY RECOVERY BITCOIN I believed I was completely lost. I was unable to withdraw money from my investment wallet after making a dubious investment, and until I discovered Best Way Hacker Company, no one could assist me in unfreezing it. This group handled my matter with attention and urgency. In a matter of days, they were able to retrieve my frozen investment and transfer it to a new wallet that I owned. They restored my hope in a big way. Best Way Hacker restored my money and my peace of mind, and for that I will always be grateful. Email.. [email protected] WhatsApp..+39-(350)-967-(1925)
24.09.25 19:56 Athea5130

ETHICAL BITCOIN HACKER/ BEST WAY RECOVERY BITCOIN I believed I was completely lost. I was unable to withdraw money from my investment wallet after making a dubious investment, and until I discovered Best Way Hacker Company, no one could assist me in unfreezing it. This group handled my matter with attention and urgency. In a matter of days, they were able to retrieve my frozen investment and transfer it to a new wallet that I owned. They restored my hope in a big way. Best Way Hacker restored my money and my peace of mind, and for that I will always be grateful. Email.. [email protected] WhatsApp..+39-(350)-967-(1925)
24.09.25 20:52 elizabethrush89

God bless Capital Crypto Recover Services for the marvelous work you did in my life, I have learned the hard way that even the most sensible investors can fall victim to scams. When my USD was stolen, for anyone who has fallen victim to one of the bitcoin binary investment scams that are currently ongoing, I felt betrayal and upset. But then I was reading a post on site when I saw a testimony of Wendy Taylor online who recommended that Capital Crypto Recovery has helped her recover scammed funds within 24 hours. after reaching out to this cyber security firm that was able to help me recover my stolen digital assets and bitcoin. I’m genuinely blown away by their amazing service and professionalism. I never imagined I’d be able to get my money back until I complained to Capital Crypto Recovery Services about my difficulties and gave all of the necessary paperwork. I was astounded that it took them 12 hours to reclaim my stolen money back. Without a doubt, my USDT assets were successfully recovered from the scam platform, Thank you so much Sir, I strongly recommend Capital Crypto Recover for any of your bitcoin recovery, digital funds recovery, hacking, and cybersecurity concerns. You reach them Call/Text Number +1 (336)390-6684 His Email: [email protected] Contact Telegram: @Capitalcryptorecover Via Contact: [email protected] His website: https://recovercapital.wixsite.com/capital-crypto-rec-1
24.09.25 20:52 elizabethrush89

God bless Capital Crypto Recover Services for the marvelous work you did in my life, I have learned the hard way that even the most sensible investors can fall victim to scams. When my USD was stolen, for anyone who has fallen victim to one of the bitcoin binary investment scams that are currently ongoing, I felt betrayal and upset. But then I was reading a post on site when I saw a testimony of Wendy Taylor online who recommended that Capital Crypto Recovery has helped her recover scammed funds within 24 hours. after reaching out to this cyber security firm that was able to help me recover my stolen digital assets and bitcoin. I’m genuinely blown away by their amazing service and professionalism. I never imagined I’d be able to get my money back until I complained to Capital Crypto Recovery Services about my difficulties and gave all of the necessary paperwork. I was astounded that it took them 12 hours to reclaim my stolen money back. Without a doubt, my USDT assets were successfully recovered from the scam platform, Thank you so much Sir, I strongly recommend Capital Crypto Recover for any of your bitcoin recovery, digital funds recovery, hacking, and cybersecurity concerns. You reach them Call/Text Number +1 (336)390-6684 His Email: [email protected] Contact Telegram: @Capitalcryptorecover Via Contact: [email protected] His website: https://recovercapital.wixsite.com/capital-crypto-rec-1
26.09.25 12:29 beverlyalex010

In 2022, I lost 1.5 ETH in what I thought was a promising Twitter investment. I reached out to the so-called brokers behind it, but they vanished and stopped replying. For years, I carried the heavy belief that my crypto was gone forever. Then, by chance, I discovered RecoveryFundProvider (recoveryfundprovider @ gmail. com WhatsApp +44 736-644-5035) through a finance podcast. That moment changed everything. Their team didn’t lure me in with false promises or flashy guarantees. Instead, they explained their process clearly specializing in advanced blockchain tracing, smart contract forensics, and even transaction reversal in certain cases. Skeptical but hopeful, I allowed them to review my case. What followed was beyond my expectations. They dug deep into the blockchain ledger, followed the coin’s complex movements across multiple addresses, and even collaborated with global nodes to trace every trail. Two weeks later, I received an alert I never thought I’d see again: my crypto had been fully recovered and safely transferred back to me. I cried tears of relief. What sets RecoveryFundProvider apart isn’t just their cutting-edge expertise, but their unwavering ethics and dedication. They treat every client like more than just another case number even years after a loss. Today, I can confidently say they live up to their name, and i am endlessly grateful.
26.09.25 15:42 elizabethrush89

God bless Capital Crypto Recover Services for the marvelous work you did in my life, I have learned the hard way that even the most sensible investors can fall victim to scams. When my USD was stolen, for anyone who has fallen victim to one of the bitcoin binary investment scams that are currently ongoing, I felt betrayal and upset. But then I was reading a post on site when I saw a testimony of Wendy Taylor online who recommended that Capital Crypto Recovery has helped her recover scammed funds within 24 hours. after reaching out to this cyber security firm that was able to help me recover my stolen digital assets and bitcoin. I’m genuinely blown away by their amazing service and professionalism. I never imagined I’d be able to get my money back until I complained to Capital Crypto Recovery Services about my difficulties and gave all of the necessary paperwork. I was astounded that it took them 12 hours to reclaim my stolen money back. Without a doubt, my USDT assets were successfully recovered from the scam platform, Thank you so much Sir, I strongly recommend Capital Crypto Recover for any of your bitcoin recovery, digital funds recovery, hacking, and cybersecurity concerns. You reach them Call/Text Number +1 (336)390-6684 His Email: [email protected] Contact Telegram: @Capitalcryptorecover Via Contact: [email protected] His website: https://recovercapital.wixsite.com/capital-crypto-rec-1
26.09.25 15:42 elizabethrush89

God bless Capital Crypto Recover Services for the marvelous work you did in my life, I have learned the hard way that even the most sensible investors can fall victim to scams. When my USD was stolen, for anyone who has fallen victim to one of the bitcoin binary investment scams that are currently ongoing, I felt betrayal and upset. But then I was reading a post on site when I saw a testimony of Wendy Taylor online who recommended that Capital Crypto Recovery has helped her recover scammed funds within 24 hours. after reaching out to this cyber security firm that was able to help me recover my stolen digital assets and bitcoin. I’m genuinely blown away by their amazing service and professionalism. I never imagined I’d be able to get my money back until I complained to Capital Crypto Recovery Services about my difficulties and gave all of the necessary paperwork. I was astounded that it took them 12 hours to reclaim my stolen money back. Without a doubt, my USDT assets were successfully recovered from the scam platform, Thank you so much Sir, I strongly recommend Capital Crypto Recover for any of your bitcoin recovery, digital funds recovery, hacking, and cybersecurity concerns. You reach them Call/Text Number +1 (336)390-6684 His Email: [email protected] Contact Telegram: @Capitalcryptorecover Via Contact: [email protected] His website: https://recovercapital.wixsite.com/capital-crypto-rec-1
26.09.25 16:40 Slimbella

I fully recommend Sylvester Bryant. He recovered €230,000 in Ethereum for me after I believed it was lost for good. His talent for tracing and reclaiming funds stolen by scammers impresses me deeply. I valued his calm, skilled approach and solid grasp of technology. This gained my confidence at every turn. If scammers have stolen your cash, contact him now. Reach out by email at yt7cracker@gmail. com or via WhatsApp at +1 512 577 7957. He dedicates himself to helping people recover their belongings. His support changed everything for me.
26.09.25 16:40 Slimbella

I fully recommend Sylvester Bryant. He recovered €230,000 in Ethereum for me after I believed it was lost for good. His talent for tracing and reclaiming funds stolen by scammers impresses me deeply. I valued his calm, skilled approach and solid grasp of technology. This gained my confidence at every turn. If scammers have stolen your cash, contact him now. Reach out by email at yt7cracker@gmail. com or via WhatsApp at +1 512 577 7957. He dedicates himself to helping people recover their belongings. His support changed everything for me.
26.09.25 19:08 beverlyalex010

In 2022, I lost 1.5 ETH in what I thought was a promising Twitter investment. I reached out to the so-called brokers behind it, but they vanished and stopped replying. For years, I carried the heavy belief that my crypto was gone forever. Then, by chance, I discovered RecoveryFundProvider ( [email protected]. WhatsApp +44 736-644-5035) through a finance podcast. That moment changed everything. Their team didn’t lure me in with false promises or flashy guarantees. Instead, they explained their process clearly specializing in advanced blockchain tracing, smart contract forensics, and even transaction reversal in certain cases. Skeptical but hopeful, I allowed them to review my case. What followed was beyond my expectations. They dug deep into the blockchain ledger, followed the coin’s complex movements across multiple addresses, and even collaborated with global nodes to trace every trail. Two weeks later, I received an alert I never thought I’d see again: my crypto had been fully recovered and safely transferred back to me. I cried tears of relief. What sets RecoveryFundProvider apart isn’t just their cutting-edge expertise, but their unwavering ethics and dedication. They treat every client like more than just another case number even years after a loss. Today, I can confidently say they live up to their name, and i am endlessly grateful.
26.09.25 19:53 carolinehudso83

You are one step away from recovering your lost crypto funds. CAPITAL REDEMPTION WIZARD is the solution. Without them, I would have lost everything. I was scammed through a compromised email, lured by a fake Elon Musk Bitcoin investment. After applying and completing KYC, I was credited with 2.5 Bitcoin. When I tried to withdraw, I was hit with fees, and my wallet was emptied of $103,000.00. Their support team was hostile. I researched and found CAPITAL REDEMPTION WIZARD. They recovered my hacked Bitcoin. I learned the Bitcoin offer was a scam. CAPITAL REDEMPTION WIZARD guided me through this. Email: ( [email protected] ) Whats app or text +1 518 468 2985 Website https://bestrecoveryagent.com/
26.09.25 22:25 Slimbella

I fully recommend Sylvester Bryant. He recovered €230,000 in Ethereum for me after I believed it was lost for good. His talent for tracing and reclaiming funds stolen by scammers impresses me deeply. I valued his calm, skilled approach and solid grasp of technology. This gained my confidence at every turn. If scammers have stolen your cash, contact him now. Reach out by email at yt7cracker@gmail. com or via WhatsApp at +1 512 577 7957. He dedicates himself to helping people recover their belongings. His support changed everything for me.
26.09.25 22:59 elizabethrush89

God bless Capital Crypto Recover Services for the marvelous work you did in my life, I have learned the hard way that even the most sensible investors can fall victim to scams. When my USD was stolen, for anyone who has fallen victim to one of the bitcoin binary investment scams that are currently ongoing, I felt betrayal and upset. But then I was reading a post on site when I saw a testimony of Wendy Taylor online who recommended that Capital Crypto Recovery has helped her recover scammed funds within 24 hours. after reaching out to this cyber security firm that was able to help me recover my stolen digital assets and bitcoin. I’m genuinely blown away by their amazing service and professionalism. I never imagined I’d be able to get my money back until I complained to Capital Crypto Recovery Services about my difficulties and gave all of the necessary paperwork. I was astounded that it took them 12 hours to reclaim my stolen money back. Without a doubt, my USDT assets were successfully recovered from the scam platform, Thank you so much Sir, I strongly recommend Capital Crypto Recover for any of your bitcoin recovery, digital funds recovery, hacking, and cybersecurity concerns. You reach them Call/Text Number +1 (336)390-6684 His Email: [email protected] Contact Telegram: @Capitalcryptorecover Via Contact: [email protected] His website: https://recovercapital.wixsite.com/capital-crypto-rec-1
26.09.25 22:59 elizabethrush89

God bless Capital Crypto Recover Services for the marvelous work you did in my life, I have learned the hard way that even the most sensible investors can fall victim to scams. When my USD was stolen, for anyone who has fallen victim to one of the bitcoin binary investment scams that are currently ongoing, I felt betrayal and upset. But then I was reading a post on site when I saw a testimony of Wendy Taylor online who recommended that Capital Crypto Recovery has helped her recover scammed funds within 24 hours. after reaching out to this cyber security firm that was able to help me recover my stolen digital assets and bitcoin. I’m genuinely blown away by their amazing service and professionalism. I never imagined I’d be able to get my money back until I complained to Capital Crypto Recovery Services about my difficulties and gave all of the necessary paperwork. I was astounded that it took them 12 hours to reclaim my stolen money back. Without a doubt, my USDT assets were successfully recovered from the scam platform, Thank you so much Sir, I strongly recommend Capital Crypto Recover for any of your bitcoin recovery, digital funds recovery, hacking, and cybersecurity concerns. You reach them Call/Text Number +1 (336)390-6684 His Email: [email protected] Contact Telegram: @Capitalcryptorecover Via Contact: [email protected] His website: https://recovercapital.wixsite.com/capital-crypto-rec-1
27.09.25 03:07 Angela_Moore

I thought my money was lost forever. Then Mr. Sylvester stepped in. He tracked down and recovered $107,000 in stablecoins , plus all my earnings. His talent for finding scam-stolen funds left me stunned. I loved how he handled everything with real expertise and solid tech skills. It got my scammed cash back safe. I trusted him completely. If you've lost funds to a scam, reach out to him now. Email [email protected] or text on WhatsApp at +1 512 577 7957. His support saved me.
28.09.25 00:42 Anitastar

Wizard Hilton Cyber Tech's strategic approach to Bitcoin recovery represents a mutually beneficial collaboration that offers valuable advantages for all involved. At the core of this innovative partnership is a shared commitment to leveraging cutting-edge technology and expertise to tackle the increasingly complex challenges of cryptocurrency theft and loss. By combining Wizard Hilton's world-class cybersecurity capabilities with the deep industry insights and recovery methodologies of Cyber Tech, this alliance is poised to revolutionize the way individuals and organizations safeguard their digital assets. Through a meticulous, multi-layered process, the team meticulously analyzes each case, employing advanced forensic techniques to trace the flow of stolen funds and identify potential recovery avenues. This rigorous approach not only maximizes the chances of successful Bitcoin retrieval, but also provides invaluable intelligence to enhance future security measures and prevention strategies. Importantly, the collaboration is built on a foundation of trust, transparency, and a genuine concern for the well-being of clients, ensuring that the recovery process is handled with the utmost care and discretion. As the cryptocurrency landscape continues to evolve, this strategic alliance between Wizard Hilton Cyber Tech stands as a shining example of how industry leaders can come together to safeguard digital assets, protect victims of cybercrime, and pave the way for a more secure and resilient cryptocurrency ecosystem. Email : wizardhiltoncybertech ( @ ) gmail (. ) com OR support ( @ ) wizardhiltoncybertech (.) com WhatsApp number +18737715701 Thanks.
28.09.25 01:48 marcushenderson624

Bitcoin Recovery Testimonial After falling victim to a cryptocurrency scam group, I lost $354,000 worth of USDT. I thought all hope was lost from the experience of losing my hard-earned money to scammers. I was devastated and believed there was no way to recover my funds. Fortunately, I started searching for help to recover my stolen funds and I came across a lot of testimonials online about Capital Crypto Recovery, an agent who helps in recovery of lost bitcoin funds, I contacted Capital Crypto Recover Service, and with their expertise, they successfully traced and recovered my stolen assets. Their team was professional, kept me updated throughout the process, and demonstrated a deep understanding of blockchain transactions and recovery protocols. They are trusted and very reliable with a 100% successful rate record Recovery bitcoin, I’m grateful for their help and highly recommend their services to anyone seeking assistance with lost crypto. Contact: [email protected] Phone CALL/Text Number: +1 (336) 390-6684 Email: [email protected] Website: https://recovercapital.wixsite.com/capital-crypto-rec-1
28.09.25 01:48 marcushenderson624

Bitcoin Recovery Testimonial After falling victim to a cryptocurrency scam group, I lost $354,000 worth of USDT. I thought all hope was lost from the experience of losing my hard-earned money to scammers. I was devastated and believed there was no way to recover my funds. Fortunately, I started searching for help to recover my stolen funds and I came across a lot of testimonials online about Capital Crypto Recovery, an agent who helps in recovery of lost bitcoin funds, I contacted Capital Crypto Recover Service, and with their expertise, they successfully traced and recovered my stolen assets. Their team was professional, kept me updated throughout the process, and demonstrated a deep understanding of blockchain transactions and recovery protocols. They are trusted and very reliable with a 100% successful rate record Recovery bitcoin, I’m grateful for their help and highly recommend their services to anyone seeking assistance with lost crypto. Contact: [email protected] Phone CALL/Text Number: +1 (336) 390-6684 Email: [email protected] Website: https://recovercapital.wixsite.com/capital-crypto-rec-1
28.09.25 01:49 marcushenderson624

Bitcoin Recovery Testimonial After falling victim to a cryptocurrency scam group, I lost $354,000 worth of USDT. I thought all hope was lost from the experience of losing my hard-earned money to scammers. I was devastated and believed there was no way to recover my funds. Fortunately, I started searching for help to recover my stolen funds and I came across a lot of testimonials online about Capital Crypto Recovery, an agent who helps in recovery of lost bitcoin funds, I contacted Capital Crypto Recover Service, and with their expertise, they successfully traced and recovered my stolen assets. Their team was professional, kept me updated throughout the process, and demonstrated a deep understanding of blockchain transactions and recovery protocols. They are trusted and very reliable with a 100% successful rate record Recovery bitcoin, I’m grateful for their help and highly recommend their services to anyone seeking assistance with lost crypto. Contact: [email protected] Phone CALL/Text Number: +1 (336) 390-6684 Email: [email protected] Website: https://recovercapital.wixsite.com/capital-crypto-rec-1
29.09.25 13:47 thomassankara

USDT recovery expert / company I thought my money was lost forever. Then Mr. Sylvester stepped in. He tracked down and recovered $107,000 in stablecoins , plus all my earnings. His talent for finding scam-stolen funds left me stunned. I loved how he handled everything with real expertise and solid tech skills. It got my scammed cash back safe. I trusted him completely. If you've lost funds to a scam, reach out to him now. Email [email protected] or text on WhatsApp at +1 512 577 7957. His support saved me.
29.09.25 16:32 elizabethrush89

God bless Capital Crypto Recover Services for the marvelous work you did in my life, I have learned the hard way that even the most sensible investors can fall victim to scams. When my USD was stolen, for anyone who has fallen victim to one of the bitcoin binary investment scams that are currently ongoing, I felt betrayal and upset. But then I was reading a post on site when I saw a testimony of Wendy Taylor online who recommended that Capital Crypto Recovery has helped her recover scammed funds within 24 hours. after reaching out to this cyber security firm that was able to help me recover my stolen digital assets and bitcoin. I’m genuinely blown away by their amazing service and professionalism. I never imagined I’d be able to get my money back until I complained to Capital Crypto Recovery Services about my difficulties and gave all of the necessary paperwork. I was astounded that it took them 12 hours to reclaim my stolen money back. Without a doubt, my USDT assets were successfully recovered from the scam platform, Thank you so much Sir, I strongly recommend Capital Crypto Recover for any of your bitcoin recovery, digital funds recovery, hacking, and cybersecurity concerns. You reach them Call/Text Number +1 (336)390-6684 His Email: [email protected] Contact Telegram: @Capitalcryptorecover Via Contact: [email protected] His website: https://recovercapital.wixsite.com/capital-crypto-rec-1
29.09.25 16:32 elizabethrush89

God bless Capital Crypto Recover Services for the marvelous work you did in my life, I have learned the hard way that even the most sensible investors can fall victim to scams. When my USD was stolen, for anyone who has fallen victim to one of the bitcoin binary investment scams that are currently ongoing, I felt betrayal and upset. But then I was reading a post on site when I saw a testimony of Wendy Taylor online who recommended that Capital Crypto Recovery has helped her recover scammed funds within 24 hours. after reaching out to this cyber security firm that was able to help me recover my stolen digital assets and bitcoin. I’m genuinely blown away by their amazing service and professionalism. I never imagined I’d be able to get my money back until I complained to Capital Crypto Recovery Services about my difficulties and gave all of the necessary paperwork. I was astounded that it took them 12 hours to reclaim my stolen money back. Without a doubt, my USDT assets were successfully recovered from the scam platform, Thank you so much Sir, I strongly recommend Capital Crypto Recover for any of your bitcoin recovery, digital funds recovery, hacking, and cybersecurity concerns. You reach them Call/Text Number +1 (336)390-6684 His Email: [email protected] Contact Telegram: @Capitalcryptorecover Via Contact: [email protected] His website: https://recovercapital.wixsite.com/capital-crypto-rec-1
29.09.25 19:46 beverlyalex010

In 2022, I lost 1.5 ETH in what I thought was a promising Twitter investment. I reached out to the so-called brokers behind it, but they vanished and stopped replying. For years, I carried the heavy belief that my crypto was gone forever. Then, by chance, I discovered RecoveryFundProvider ( recoveryfundprovider@gmail. com WhatsApp +44 736-644-5035) through a finance podcast. That moment changed everything. Their team didn’t lure me in with false promises or flashy guarantees. Instead, they explained their process clearly specializing in advanced blockchain tracing, smart contract forensics, and even transaction reversal in certain cases. Skeptical but hopeful, I allowed them to review my case. What followed was beyond my expectations. They dug deep into the blockchain ledger, followed the coin’s complex movements across multiple addresses, and even collaborated with global nodes to trace every trail. Two weeks later, I received an alert I never thought I’d see again: my crypto had been fully recovered and safely transferred back to me. I cried tears of relief. What sets RecoveryFundProvider apart isn’t just their cutting-edge expertise, but their unwavering ethics and dedication. They treat every client like more than just another case number even years after a loss. Today, I can confidently say they live up to their name, and i am endlessly grateful.
29.09.25 21:06 beverlyalex010

I ended my marriage. My spouse was unfaithful. I found clear proof of her cheating. She hid her phone activity. Many secrets were on her phone. She used different apps. I hired a private investigator. I needed solid evidence first. I did not want to accuse her without proof. That could lead to legal trouble. They helped me access her phone. They linked her phone use to mine. I could then watch her phone without her knowing. This is how I learned about her affair. I also found out she planned to take my money. She intended to leave with her new partner. If you are in a similar situation, reach out to [email protected] WhatsApp at +44 736-644-5035. Get ahead of things.
29.09.25 21:07 beverlyalex010

I ended my marriage. My spouse was unfaithful. I found clear proof of her cheating. She hid her phone activity. Many secrets were on her phone. She used different apps. I hired a private investigator. I needed solid evidence first. I did not want to accuse her without proof. That could lead to legal trouble. They helped me access her phone. They linked her phone use to mine. I could then watch her phone without her knowing. This is how I learned about her affair. I also found out she planned to take my money. She intended to leave with her new partner. If you are in a similar situation, reach out to [email protected] WhatsApp at +44 736-644-5035. Get ahead of things.
29.09.25 21:07 beverlyalex010

I ended my marriage. My spouse was unfaithful. I found clear proof of her cheating. She hid her phone activity. Many secrets were on her phone. She used different apps. I hired a private investigator. I needed solid evidence first. I did not want to accuse her without proof. That could lead to legal trouble. They helped me access her phone. They linked her phone use to mine. I could then watch her phone without her knowing. This is how I learned about her affair. I also found out she planned to take my money. She intended to leave with her new partner. If you are in a similar situation, reach out to [email protected] WhatsApp at +44 736-644-5035. Get ahead of things.
29.09.25 21:07 beverlyalex010

I ended my marriage. My spouse was unfaithful. I found clear proof of her cheating. She hid her phone activity. Many secrets were on her phone. She used different apps. I hired a private investigator. I needed solid evidence first. I did not want to accuse her without proof. That could lead to legal trouble. They helped me access her phone. They linked her phone use to mine. I could then watch her phone without her knowing. This is how I learned about her affair. I also found out she planned to take my money. She intended to leave with her new partner. If you are in a similar situation, reach out to [email protected] WhatsApp at +44 736-644-5035. Get ahead of things.
29.09.25 21:07 beverlyalex010

I ended my marriage. My spouse was unfaithful. I found clear proof of her cheating. She hid her phone activity. Many secrets were on her phone. She used different apps. I hired a private investigator. I needed solid evidence first. I did not want to accuse her without proof. That could lead to legal trouble. They helped me access her phone. They linked her phone use to mine. I could then watch her phone without her knowing. This is how I learned about her affair. I also found out she planned to take my money. She intended to leave with her new partner. If you are in a similar situation, reach out to [email protected] WhatsApp at +44 736-644-5035. Get ahead of things.
29.09.25 21:07 beverlyalex010

I ended my marriage. My spouse was unfaithful. I found clear proof of her cheating. She hid her phone activity. Many secrets were on her phone. She used different apps. I hired a private investigator. I needed solid evidence first. I did not want to accuse her without proof. That could lead to legal trouble. They helped me access her phone. They linked her phone use to mine. I could then watch her phone without her knowing. This is how I learned about her affair. I also found out she planned to take my money. She intended to leave with her new partner. If you are in a similar situation, reach out to [email protected] WhatsApp at +44 736-644-5035. Get ahead of things.
29.09.25 21:07 beverlyalex010

I ended my marriage. My spouse was unfaithful. I found clear proof of her cheating. She hid her phone activity. Many secrets were on her phone. She used different apps. I hired a private investigator. I needed solid evidence first. I did not want to accuse her without proof. That could lead to legal trouble. They helped me access her phone. They linked her phone use to mine. I could then watch her phone without her knowing. This is how I learned about her affair. I also found out she planned to take my money. She intended to leave with her new partner. If you are in a similar situation, reach out to [email protected] WhatsApp at +44 736-644-5035. Get ahead of things.
29.09.25 21:07 beverlyalex010

I ended my marriage. My spouse was unfaithful. I found clear proof of her cheating. She hid her phone activity. Many secrets were on her phone. She used different apps. I hired a private investigator. I needed solid evidence first. I did not want to accuse her without proof. That could lead to legal trouble. They helped me access her phone. They linked her phone use to mine. I could then watch her phone without her knowing. This is how I learned about her affair. I also found out she planned to take my money. She intended to leave with her new partner. If you are in a similar situation, reach out to [email protected] WhatsApp at +44 736-644-5035. Get ahead of things.
29.09.25 21:07 beverlyalex010

I ended my marriage. My spouse was unfaithful. I found clear proof of her cheating. She hid her phone activity. Many secrets were on her phone. She used different apps. I hired a private investigator. I needed solid evidence first. I did not want to accuse her without proof. That could lead to legal trouble. They helped me access her phone. They linked her phone use to mine. I could then watch her phone without her knowing. This is how I learned about her affair. I also found out she planned to take my money. She intended to leave with her new partner. If you are in a similar situation, reach out to [email protected] WhatsApp at +44 736-644-5035. Get ahead of things.
29.09.25 21:07 beverlyalex010

I ended my marriage. My spouse was unfaithful. I found clear proof of her cheating. She hid her phone activity. Many secrets were on her phone. She used different apps. I hired a private investigator. I needed solid evidence first. I did not want to accuse her without proof. That could lead to legal trouble. They helped me access her phone. They linked her phone use to mine. I could then watch her phone without her knowing. This is how I learned about her affair. I also found out she planned to take my money. She intended to leave with her new partner. If you are in a similar situation, reach out to [email protected] WhatsApp at +44 736-644-5035. Get ahead of things.
29.09.25 21:07 beverlyalex010

I ended my marriage. My spouse was unfaithful. I found clear proof of her cheating. She hid her phone activity. Many secrets were on her phone. She used different apps. I hired a private investigator. I needed solid evidence first. I did not want to accuse her without proof. That could lead to legal trouble. They helped me access her phone. They linked her phone use to mine. I could then watch her phone without her knowing. This is how I learned about her affair. I also found out she planned to take my money. She intended to leave with her new partner. If you are in a similar situation, reach out to [email protected] WhatsApp at +44 736-644-5035. Get ahead of things.
29.09.25 21:07 beverlyalex010

I ended my marriage. My spouse was unfaithful. I found clear proof of her cheating. She hid her phone activity. Many secrets were on her phone. She used different apps. I hired a private investigator. I needed solid evidence first. I did not want to accuse her without proof. That could lead to legal trouble. They helped me access her phone. They linked her phone use to mine. I could then watch her phone without her knowing. This is how I learned about her affair. I also found out she planned to take my money. She intended to leave with her new partner. If you are in a similar situation, reach out to [email protected] WhatsApp at +44 736-644-5035. Get ahead of things.
29.09.25 21:07 beverlyalex010

I ended my marriage. My spouse was unfaithful. I found clear proof of her cheating. She hid her phone activity. Many secrets were on her phone. She used different apps. I hired a private investigator. I needed solid evidence first. I did not want to accuse her without proof. That could lead to legal trouble. They helped me access her phone. They linked her phone use to mine. I could then watch her phone without her knowing. This is how I learned about her affair. I also found out she planned to take my money. She intended to leave with her new partner. If you are in a similar situation, reach out to [email protected] WhatsApp at +44 736-644-5035. Get ahead of things.
30.09.25 11:02 patricialovick86

How To Recover Your Bitcoin Without Falling Victim To Scams: A Testimony Experience With Capital Crypto Recover Services, Contact Telegram: @Capitalcryptorecover Dear Everyone, I would like to take a moment to share my positive experience with Capital Crypto Recover Services. Initially, I was unsure if it would be possible to recover my stolen bitcoins. However, with their expertise and professionalism, I was able to fully recover my funds. Unfortunately, many individuals fall victim to scams in the cryptocurrency space, especially those involving fraudulent investment platforms. However, I advise caution, as not all recovery services are legitimate. I personally lost $273,000 worth of Bitcoin from my Binance account due to a deceptive platform. If you have suffered a similar loss, you may be considering crypto recovery, The Capital Crypto Recover is the most knowledgeable and effective Capital Crypto Recovery Services assisted me in recovering my stolen funds within 24 hours, after getting access to my wallet. Their service was not only prompt but also highly professional and effective, and many recovery services may not be trustworthy. Therefore, I highly recommend Capital Crypto Recover to you. i do always research and see reviews about their service, For assistance finding your misplaced cryptocurrency, get in touch with them, They do their jobs quickly and excellently, Stay safe and vigilant in the crypto world. Contact: [email protected] You can reach them via email at [email protected] OR Call/Text Number +1 (336)390-6684 his contact website: https://recovercapital.wixsite.com/capital-crypto-rec-1
30.09.25 11:02 patricialovick86

How To Recover Your Bitcoin Without Falling Victim To Scams: A Testimony Experience With Capital Crypto Recover Services, Contact Telegram: @Capitalcryptorecover Dear Everyone, I would like to take a moment to share my positive experience with Capital Crypto Recover Services. Initially, I was unsure if it would be possible to recover my stolen bitcoins. However, with their expertise and professionalism, I was able to fully recover my funds. Unfortunately, many individuals fall victim to scams in the cryptocurrency space, especially those involving fraudulent investment platforms. However, I advise caution, as not all recovery services are legitimate. I personally lost $273,000 worth of Bitcoin from my Binance account due to a deceptive platform. If you have suffered a similar loss, you may be considering crypto recovery, The Capital Crypto Recover is the most knowledgeable and effective Capital Crypto Recovery Services assisted me in recovering my stolen funds within 24 hours, after getting access to my wallet. Their service was not only prompt but also highly professional and effective, and many recovery services may not be trustworthy. Therefore, I highly recommend Capital Crypto Recover to you. i do always research and see reviews about their service, For assistance finding your misplaced cryptocurrency, get in touch with them, They do their jobs quickly and excellently, Stay safe and vigilant in the crypto world. Contact: [email protected] You can reach them via email at [email protected] OR Call/Text Number +1 (336)390-6684 his contact website: https://recovercapital.wixsite.com/capital-crypto-rec-1
01.10.25 16:51 beverlyalex010

In 2022, I lost 1.5 ETH in what I thought was a promising Twitter investment. I reached out to the so-called brokers behind it, but they vanished and stopped replying. For years, I carried the heavy belief that my crypto was gone forever. Then, by chance, I discovered RecoveryFundProvider ( [email protected] WhatsApp +44 736-644-5035) through a finance podcast. That moment changed everything. Their team didn’t lure me in with false promises or flashy guarantees. Instead, they explained their process clearly specializing in advanced blockchain tracing, smart contract forensics, and even transaction reversal in certain cases. Skeptical but hopeful, I allowed them to review my case. What followed was beyond my expectations. They dug deep into the blockchain ledger, followed the coin’s complex movements across multiple addresses, and even collaborated with global nodes to trace every trail. Two weeks later, I received an alert I never thought I’d see again: my crypto had been fully recovered and safely transferred back to me. I cried tears of relief. What sets RecoveryFundProvider apart isn’t just their cutting-edge expertise, but their unwavering ethics and dedication. They treat every client like more than just another case number even years after a loss. Today, I can confidently say they live up to their name, and I’m endlessly grateful.
01.10.25 17:24 johnn

Anthony davies, renowned for his expertise in recovering stolen cryptocurrency, especially specializing in USDT, provided invaluable assistance in a scenario where a significant sum of $571,000 was taken from me. I had the privilege of witnessing his exceptional skills firsthand and I am truly thankful for his prompt efforts, which led to the successful recovery of the entire amount in just a span of 72 hours. Mr Anthony davies swift reactions and efficient tactics not only resolved my financial troubles but also alleviated much of the stress on my mental well-being. You can reach out to him immediately and get connected with email at anthonydaviestech@gmail com also can be contacted on WhatsApp at +951 490-8435, he is an expert in the field most especially in recovering lost digital assets.
01.10.25 17:25 johnn

Anthony davies, renowned for his expertise in recovering stolen cryptocurrency, especially specializing in USDT, provided invaluable assistance in a scenario where a significant sum of $571,000 was taken from me. I had the privilege of witnessing his exceptional skills firsthand and I am truly thankful for his prompt efforts, which led to the successful recovery of the entire amount in just a span of 72 hours. Mr Anthony davies swift reactions and efficient tactics not only resolved my financial troubles but also alleviated much of the stress on my mental well-being. You can reach out to him immediately and get connected with email at anthonydaviestech@gmail com also can be contacted on WhatsApp at +951 490-8435, he is an expert in the field most especially in recovering lost digital assets.