1. A computer-implemented method, comprising: determining, by a system operatively coupled to a processor, digest information for a video, wherein the digest information comprises objects appearing in the video and respective times at which the objects appear in the video; comparing, by the system, the digest information with reference digest information for reference videos, wherein the reference digest information identifies reference objects appearing in the reference videos and respective reference times at which the reference objects appear in the reference videos; determining, by the system, whether the video comprises content included in one or more of the reference videos based on a degree of similarity between the digest information and reference digest information associated with one or more of the reference videos, thereby facilitating improved processing time and accuracy for automatic detection of unauthorized usage of reference video content; identifying, by the system, a base time length separating two of the objects appearing in the video at different times; and employing, by the system, a ratio of the base time length relative to a reference time length separating two first reference objects corresponding to two of the objects to determine whether the video comprises first content included in the first reference video of the reference videos.