[FFmpeg-devel] SDR->HDR tone mapping algorithm?

[Guo, Yejun]

> -----Original Message-----
> From: ffmpeg-devel [mailto:ffmpeg-devel-bounces at ffmpeg.org] On Behalf
> Of Harish Krupo
> Sent: Friday, February 08, 2019 4:17 PM
> To: FFmpeg development discussions and patches <ffmpeg-
> devel at ffmpeg.org>
> Cc: Strasser, Kevin <kevin.strasser at intel.com>; Palli, Tapani
> <tapani.palli at intel.com>; Sharma, Shashank <shashank.sharma at intel.com>
> Subject: [FFmpeg-devel] SDR->HDR tone mapping algorithm?
> 
> Hello,
> 
> We are in the process of implementing HDR rendering support in the
> Weston display compositor [1] (HDR discussion here [2]). When HDR
> and SDR surfaces like a video buffer and a subtitle buffer are presented
> together, the composition would take place as follows:
> - If the display does not support HDR metadata:
>   in-coming HDR surfaces would be tone mapped using opengl to SDR and
>   blended with the other SDR surfaces. We are currently using the Hable
>   operator for tone mapping.
> - If the display supports setting HDR metadata:
>   SDR surfaces would be tone mapped to HDR and blended with HDR surfaces.
> 
> The literature available for SDR->HDR tone mapping varies from simple
> linear expansion of luminance to CNN based approaches. We wanted to
> know
> your recommendations for an acceptable algorithm for SDR->HDR tone
> mapping.
> 

In ITU-R BT.2390 (https://www.itu.int/pub/R-REP-BT.2390) section 10, there is a
discussion on the approach to preserve the look of the SDR content when shown on an HDR display.

BTW, just curious why the HLG video/display is not considered in the wayland compositor, thanks.

> Any help is greatly appreciated!
> 
> [1] https://gitlab.freedesktop.org/wayland/weston
> [2] https://lists.freedesktop.org/archives/wayland-devel/2019-
> January/039809.html
> 
> Thank you
> Regards
> Harish Krupo
> _______________________________________________
> ffmpeg-devel mailing list
> ffmpeg-devel at ffmpeg.org
> http://ffmpeg.org/mailman/listinfo/ffmpeg-devel