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- Joined: Tue Apr 28, 2015 10:41 pm
Andrew Kolakowski wrote:MOV or other container should be really irrelevant as the same color metadata should be in actual codec (VP9/h264/h265/ProRes etc.) headers and through the browser's video engine passed to OS color management.
that's perhaps your private opinion, but in fact it can be defined in both ways, and the ]'colr' parameters atom in quicktime and its corresponding slightly modified counterpart im MPEG-4 are in fact the more common variants and in fact prioritized by the ISOBMFF standard (see: https://poynton.ca/notes/misc/sde-nclc-vui-nclx.html). it's also a more general kind of description, which can be adapted to different file formats without additional code, precedence issues and different ways to specify color information in every codec again (see: https://github.com/Netflix/vp9-dash/issues/5 for a real world conflict of this kind). i really understand your POV, but you will hardly change all the complexity and historically grown divergences in this field solely by your convincing voice.
but in practice you will hardly see any issues related to this topic in .mp4 files. it's more or less only apples crazy practice, to make anything as incompatible as possible -- like forcing a rec.601 interpretation instead of rec.709 for HD content, if not explicitly defined otherwise --, which makes the whole story very difficult and incompatible in practice.
Andrew Kolakowski wrote:It's all doable, but not in anyones interest...
many aspects of this issue are really hard to change or improve, without inducing new incompatibilities. it reminds me of this annoying off-by-one synchronization issues, which plagued the old QT implementation from apple for a long time. all other software had to fix it by ad hoc hacks, to provide compatibility. an now, this old QT implementation is slowly vanishing and the new apple mediaframwork doesn't show this issue anymore, but we suddenly face off-by-one issues in the other direction, because the old questionable 'fixes' are still present in most non-apple software. it's really horrible practice, to solve compatibility issues, which are in fact just caused by one proprietary software and its bugs, in such a manner. and i really don't understand, why ProRes, which is in fact the file format, which undoubtedly should be seen as the most affected one of this kind of issues, is still commonly seen as the gold standard of professional video file exchange?