You've already forked FFmpeg
mirror of
https://github.com/FFmpeg/FFmpeg.git
synced 2025-11-29 05:57:37 +02:00
c9168717bf
Right now, the private contexts of every decoder supporting H.274 film grain synthesis (namely H.264, HEVC and VVC) contain a H274FilmGrainDatabase; said structure is very large 700442B before this commit) and takes up the overwhelming majority of said contexts: Removing it reduces sizeof(H264Context) by 92.88%, sizeof(HEVCContext) by 97.78% and sizeof(VVCContext) by 99.86%. This is especially important for H.264 and HEVC when using frame-threading. The content of said film grain database does not depend on any input parameter; it is shareable between all its users and could be hardcoded in the binary (but isn't, because it is so huge). This commit adds a database with static storage duration to h274.c and uses it instead of the elements in the private contexts above. It is still lazily initialized as-needed; a mutex is used for the necessary synchronization. An alternative would be to use an AV_ONCE to initialize the whole database either in the decoders' init function (which would be wasteful given that most videos don't use film grain synthesis) or in ff_h274_apply_film_grain(). Reviewed-by: Niklas Haas <ffmpeg@haasn.dev> Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>