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Since the majority of people have smartphones, the Hb level can be determined using the smartphone's video through PPG signal as opposed to the traditional approaches, which still require the use of a needle to puncture a vein. This study enrolled 108 subjects who underwent a clinical test, with their hemoglobin (Hb) level within the range of 6.6 to 16.5 g/dL. To mitigate potential variability in Hb levels during a brief period, 15-second recordings of the pointer finger were captured by utilizing a smartphone prior to the clinical test. When the user places their finger on the phone's camera to record data, the camera flashlight briefly illuminates the area. The captured video is transformed to 60 fps as capturing a PPG signal at 60 fps provides a more detailed and accurate representation of changes in blood volume and heart rate compared to a lower frame rate鉴于当前多数民众均持有智能手机，本研究无需采用传统需静脉穿刺采血的检测方式，而是通过智能手机拍摄的视频采集光电容积描记（PPG, photoplethysmography）信号，以此测定血红蛋白（Hb）水平。本研究共招募108名受试者开展临床试验，其血红蛋白水平介于6.6至16.5 g/dL之间。为缓解短时间内血红蛋白水平的潜在波动，本研究于临床试验开始前，通过智能手机采集受试者食指15秒的视频数据。当受试者将手指置于手机摄像头上方进行数据采集时，摄像头闪光灯会短暂照亮该采集区域。采集得到的视频将被转换为60帧每秒（fps）的帧率，这是因为相较于较低帧率，以60 fps采集PPG信号能够更细致、精准地反映血容量与心率的动态变化。