A blood pressure measuring method, comprising: obtaining at least one video that captures a first body area and a second body area of a testee, wherein each video from the at least one video includes a plurality of frames; extracting, from the frames of the at least one video, a plurality of gray scale values for corresponding images that capture the first body area and a plurality of gray scale values for corresponding images that capture the second body area; drawing a pulse-wave waveform of the first body area based on the plurality of gray scale values for the corresponding images of the first body area, and drawing a pulse-wave waveform of the second body area based on the plurality of gray scale values for the corresponding images of the second body area; determining a pulse-wave propagation time based on the pulse-wave waveform of the first body area and the pulse-wave waveform of the second body area; and obtaining a blood pressure value of the testee based on a corresponding relation between the pulse-wave propagation time and blood pressure, wherein the extracting, from the frames of the at least one video, a plurality of gray scale values for corresponding images that capture the first body area and a plurality of gray scale values for corresponding images that capture the second body area comprises: identifying a corresponding image of the first body area and a corresponding image of the second body area from each frame of the at least one video; and extracting a gray scale value of a red channel signal in the corresponding image of the first body area and a gray scale value of a red channel signal in the corresponding image of the second body area from each frame of the at least one video. obtaining at least one video that captures a first body area and a second body area of a testee, wherein each video from the at least one video includes a plurality of frames; extracting, from the frames of the at least one video, a plurality of gray scale values for corresponding images that capture the first body area and a plurality of gray scale values for corresponding images that capture the second body area; drawing a pulse-wave waveform of the first body area based on the plurality of gray scale values for the corresponding images of the first body area, and drawing a pulse-wave waveform of the second body area based on the plurality of gray scale values for the corresponding images of the second body area; determining a pulse-wave propagation time based on the pulse-wave waveform of the first body area and the pulse-wave waveform of the second body area; and obtaining a blood pressure value of the testee based on a corresponding relation between the pulse-wave propagation time and blood pressure, wherein the extracting, from the frames of the at least one video, a plurality of gray scale values for corresponding images that capture the first body area and a plurality of gray scale values for corresponding images that capture the second body area comprises: identifying a corresponding image of the first body area and a corresponding image of the second body area from each frame of the at least one video; and extracting a gray scale value of a red channel signal in the corresponding image of the first body area and a gray scale value of a red channel signal in the corresponding image of the second body area from each frame of the at least one video. identifying a corresponding image of the first body area and a corresponding image of the second body area from each frame of the at least one video; and extracting a gray scale value of a red channel signal in the corresponding image of the first body area and a gray scale value of a red channel signal in the corresponding image of the second body area from each frame of the at least one video.