Facial expression detection method of density optical flow feature in video

The invention relates to the technical field of expression detection, and particularly discloses a facial expression detection method of a density optical flow feature in a video, and the method comprises the steps: extracting a plurality of frames of to-be-detected face images from a face video, carrying out the processing, obtaining a corrected face image, carrying out the detection of face key points, and obtaining 68 face key points; extracting the density optical flow of the face image of the ith frame and the face image of the (i + k) th frame after correction, and converting the density optical flow into a BGR space image; respectively extracting eyebrow and mouth area images of the BGR space image according to 68 face key points, and obtaining a target image; and constructing a facial expression recognition model according to the training target image in the target images and the corresponding label, and inputting the test target image in the target images into the facial expression recognition model