Some command-line tools for media
PPM-list → hash64(RGB frame pixels)-list, e.g. for "trust-but-verify" frame accuracy for extracting clips.
cat foo.mp4 | \
ffmpeg -loglevel warning -i - -f image2pipe -c ppm - | \
hash-frames > foo.mp4.hashes
The current hash function is cityhash (64-bit).
cd mac-show-ppms && \
xcodebuild && \
cat foo.mp4 | \
ffmpeg -loglevel warning -i - -f image2pipe -c ppm - | \
./build/Release/show-ppms.app/Contents/MacOS/show-ppms
The current implementation plays frames as quickly as it can, which is approximately the right speed for my use case.
TODO: improve performance, take --fps= argument.