System and method for automatically detecting shot boundary and key frame from a compressed video data

摘要

A system for detecting shot boundary in a compressed video data without decompression includes a difference detector that detects content difference between frames. When the difference detector determines that a first content difference between a current frame of the current group of frames and a previous frame of a first previous group of frames is greater than a first threshold, a sharp shot boundary detector detects a sharp shot boundary within the current group of frames. When the difference detector determines that the first content difference is not greater than the first threshold but a second content difference between the current frame and a previous frame of a second previous group of frames is greater than a second threshold, a gradual shot boundary detector detects a gradual shot boundary within the current group of frames. The gradual shot boundary detector includes a pan frame detector that detects pan boundaries, a zoom detector that detects zoom boundaries, and key frame detector that detects key frames. A threshold selection unit is coupled to the difference detector to select the thresholds in accordance with the content difference detected such that the sharp shot boundary detector, the gradual shot boundary detector, and the key frame function efficiently and effectively.