Target positioning method, apparatus and system

A target positioning apparatus, comprising:

• a memory storing computer program instructions;
• and a processor coupled to the memory and configured to execute the computer program instructions and perform:
• determining, in response to determining that a video frame image including a target lesion is detected from a video stream, location information of the target lesion on the video frame image;
• and
• tracking the target lesion according to the location information of the target lesion on the video frame image, comprising:
• using a region image corresponding to the location information of the target lesion on the video frame image as a template region image;
• selecting a preset range region image centered on the location information from a video frame image in the video stream as a search region image;
• respectively mapping the search region image and the template region image to a set-dimensional feature space based on a convolutional neural network, to obtain search feature vectors corresponding to the search region image and template feature vectors corresponding to the template region image;
• performing a two-dimensional convolution operation on the search feature vectors and the template feature vectors to determine a second similarity value between each image block in the search region image and the template region image, each image block being obtained by sliding a sliding window on the search region image with a preset stride;
• using a two-dimensional matrix formed by arranging the second similarity values according to positions of corresponding image blocks on the search region image as a first similarity value between the search region image and the template region image;
• in response to determining that the first similarity value satisfies a similarity condition, determining that the target lesion is tracked down, and determining location information of the target lesion on the search region image.

A non-transitory computer-readable storage medium storing computer program instructions executable by at least one processor to perform:

• determining, in response to determining that a video frame image including a target lesion is detected from a video stream, location information of the target lesion on the video frame image;
• and
• tracking the target lesion according to the location information of the target lesion on the video frame image, comprising:
• using a region image corresponding to the location information of the target lesion on the video frame image as a template region image;
• selecting a preset range region image centered on the location information from a video frame image in the video stream as a search region image;
• respectively mapping the search region image and the template region image to a set-dimensional feature space based on a convolutional neural network, to obtain search feature vectors corresponding to the search region image and template feature vectors corresponding to the template region image;
• performing a two-dimensional convolution operation on the search feature vectors and the template feature vectors to determine a second similarity value between each image block in the search region image and the template region image, each image block being obtained by sliding a sliding window on the search region image with a preset stride;
• using a two-dimensional matrix formed by arranging the second similarity values according to positions of corresponding image blocks on the search region image as a first similarity value between the search region image and the template region image;
• in response to determining that the first similarity value satisfies a similarity condition, determining that the target lesion is tracked down, and determining location information of the target lesion on the search region image.