Image processor, image processing method, and computer program

An image processing method for an image processor to track a picture of a target in a movie, the image processing method comprising:

• acquiring an image frame making up the movie from an imaging device and storing the image frame in a memory;
• acquiring a depth image for the image frame making up the movie, the depth image representing, as a pixel value on an image plane, a subject distance from the imaging device;
• reading the image frame from the memory, generating an edge image for the image frame, and identifying a picture area of a tracked target in the depth image on a basis of an outline of the tracked target represented by tracking results for the image frame at a previous time so as to extract an edge in an area limited on a basis of the picture area from the edge image;
• and
• comparing the extracted edges against an outline candidate for the tracked target to find a likelihood so as to estimate the outline of the tracked target and store the outline as tracking results in the memory.

A computer program causing a computer for tracking a picture of a target in a movie to achieve, the computer program comprising:

• acquiring a depth image for an image frame making up the movie, the depth image representing, as a pixel value on an image plane, a subject distance from an imaging device;
• generating an edge image for the image frame and identifying a picture area of a tracked target in the depth image on a basis of an outline of the tracked target represented by tracking results for the image frame at a previous time so as to extract an edge in an area limited on a basis of the picture area from the edge image;
• and
• comparing the extracted edge against an outline candidate for the tracked target to find a likelihood so as to estimate the outline of the tracked target and output the outline as tracking results.