[FFmpeg-devel] [PATCH] h264: Add support for alternative transfer characterics SEI

[Hendrik Leppkes]

On Tue, Aug 8, 2017 at 4:36 PM, Vittorio Giovara
<vittorio.giovara at gmail.com> wrote:
> The use of this SEI is for backward compatibility in HLG HDR systems:
> older devices that cannot interpret the "arib-std-b67" transfer will
> get the compatible transfer (usually bt709 or bt2020) from the VUI,
> while newer devices that can interpret HDR will read the SEI and use
> its value instead.
>

Following their logic, what if I can't deal with HLG yet, and I want
the original transfer?
Maybe it should be exported somehow, or have an option to not use the
alternate one, or something?

One of the key points of HLG is compatibility with non-HDR systems, so
if the bitstream already offers this choice, maybe so should we,
without having to "guess" if its bt709 or bt2020 or...?

- Hendrik