[FFmpeg-devel] [GSoC] [PATCH 2/2] mlpenc: Working MLP/TrueHD encoder

[Andy Furniss]

Jai Luthra wrote:
> * Multichannel support for TrueHD is experimental
>
> There should be downmix substreams present for 2+ channel
> bitstreams, but ffmpeg decoder doesn't need it. Will add support for
> this soon.

Nice work, this is just a sort of related question really from a user
who hasn't taken any notice of TrueHD for a few years.

Last I looked I couldn't find much in the way of specs for TrueHD and
noticed that the Decoder didn't have anything related to dynamic range
control.

Is there more info about now?

IIRC testing decoder - (depending on content) for downmix or 2 channel
sub stream the absence of DRC was a bit of a show stopper in that full
range can be way too much. The AC3 version of course did have DRC meta
and ffmpeg would correctly fully apply it for downmix, so for a stereo
listener like me AC3 = good, TrueHD (or DTS) = bad.