Gait big data retrieval method and system and terminal equipment

The invention discloses a gait big data retrieval method, a gait big data retrieval system and terminal equipment, belongs to the technical field of gait recognition, and can realize that a user regularly and correctly uses a gait retrieval technology and obtains an optimal retrieval effect, so that target person track information is more abundant and more accurate drawn on the basis of a retrieval result, and the user experience is improved. The problem that retrieval effects vary from person to person is solved. The method comprises the following steps: S1, acquiring a video image containing a target person, extracting a gait sample of the target person from the video image, and constructing a gait library of the target person according to the gait sample; s2, retrieving in the monitoring video data of the local area by using the gait library to obtain a local retrieval result, and updating the gait library by using the local retrieval result to obtain an updated gait library; s3, performing retrieval in gl