[FFmpeg-devel] [PATCH] lavc/hevc Parse SEI_TYPE_MASTERING_DISPLAY_INFO and propagate contents into the AVMasteringDisplayMetadata side data.

[Michael Niedermayer]

On Fri, Jan 22, 2016 at 02:54:21PM -0800, Neil Birkbeck wrote:
> Hmm. I don't have a good idea of how likely it is for this conversion to
> float (by dividing a constant) to not be bit-exact on different
> architectures (compilers?) when there should not be any other math
> transforming the metadata (other than the conversion back to the integer
> coding for cases like hevc, which for a given architecture is possible
> without loss). The fact that this could happen at all does make it annoying
> in terms of bit-exact test expectations across arch, and this is the main
> concern, right? (for this type of metadata, it is really a hint to
> TVs/algorithms, and some will ignore it altogether)

bitexactness is one concern, also theres the issue with what is ideally
correct.
that is what are the ideal values dictated by various standards
that hardware (cammeras, ...) aim at ?
are these rational or float or what can represent them better ?


[...]
-- 
Michael     GnuPG fingerprint: 9FF2128B147EF6730BADF133611EC787040B0FAB

Those who are best at talking, realize last or never when they are wrong.
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