Difference-guided video analysis

A system comprising:

• one or more processors;
• and
• one or more computer-readable storage media storing program instructions which, when executed by the one or more processors, are configured to cause the one or more processors to perform a method comprising:
• obtaining, from a video having a first resolution, a set of frames having a second resolution, the first resolution being higher than the second resolution,
• wherein the set of frames comprises a first frame and a second frame adjacent to the first frame;
• generating, based on the first frame and the second frame, a difference feature map;
• obtaining, from the video, a third frame having the first resolution, the third frame having a third frame area;
• detecting, based on the difference feature map, a first location of a first object in the third frame;
• cropping, from the third frame, a first cropped area corresponding to the first object, the first cropped area being smaller than the third frame area;
• generating a first feature map of the first cropped area;
• generating, based on the first feature map and the difference feature map, a spatial attention layer;
• and
• detecting, by the spatial attention layer, the first object in the first cropped area.

A computer program product comprising one or more computer readable storage media, and program instructions collectively stored on the one or more computer readable storage media, the program instructions executable by one or more processors to cause the one or more processors to perform a method comprising:

• obtaining, from a video having a first resolution, a set of frames having a second resolution, the first resolution being higher than the second resolution,
• wherein the set of frames comprises a first frame and a second frame adjacent to the first frame;
• generating, based on the first frame and the second frame, a difference feature map;
• obtaining, from the video, a third frame having the first resolution, the third frame having a third frame area;
• detecting, based on the difference feature map, a first location of a first object in the third frame;
• cropping, from the third frame, a first cropped area corresponding to the first object, the first cropped area being smaller than the third frame area;
• generating a first feature map of the first cropped area;
• generating, based on the first feature map and the difference feature map, a spatial attention layer;
• and
• detecting, by the spatial attention layer, the first object in the first cropped area.