(Figure 1) To monitor audio-visual content which includes captions, caption fingerprints are derived from a length of each word in the caption, without regard to the identity of the character or characters forming the word. Audio-visual content is searched to identify a caption event having a matching fingerpri...

A method of identifying an item of video content involves providing a spatial hash value and a temporal hash value for each image in a video collection. Each hash value is based on a measure of the entropy in differences between pixel values.A table of the pair of hash values against timecode is created and ordered ...