Thanks. But I'd much prefer it if there was a numerical value as the result (1 value for entire video), so I could compare different encodings to the original (source) video and the numerical value for each would let me know which were the closest matches.
something like:
video A encode is 100% the same as source video
video B encode is 95% the same as source video
or
video A. signal to noise ratio (compared to source video) is 99999:1 [video A is very close to source video]
video B. signal to noise ratio (compared to source video) is 1:1 [video B is very unlike source video]
Maybe I've not got the term quite right but I'm looking for a a simple way of comparing different video encodings of a source video, to determine what particular video formats/encoding formats/parameters produce the most similar video to the original source videos (without doing a visual check for encoding artefacts).
The difference matte would give a difference for each frame as image frames (a video) rather than 1 numerical value for the difference between the entire videos. The one numerical result per encoded video would make it a lot easier to compare lots of different video encodes, with different parameters (against different source videos) - without visually looking at each frame produced by the difference-matte method.
