[FFmpeg-devel] [PATCH 1/6] truehd_core: Disable 16-channel presentation

[Paul B Mahol]

On 7/6/19, Andreas Rheinhardt <andreas.rheinhardt at gmail.com> wrote:
> The most serious bit of the substream_info header field (in a mayor sync
> packet) indicates whether a 16-channel presentation is present in the
> bitstream. If set, the extended_substream_info header field contains
> information about the 16-channel presentation. This presentation always
> uses substream 3, a substream that is discarded by truehd_core. So
> substream_info needs to be changed to no longer indicate the presence
> of a 16-channel presentation in order for truehd_core's output to be
> consistent. This is implemented in this commit.
>
> This change also makes MediaInfo no longer display the presence of Atmos
> in the output of truehd_core.
>
> Also, set the (now irrelevant) extended_substream_info field to zero as
> this seems to be the common value for ordinary TrueHD.
>
> Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt at gmail.com>
> ---
> The info this patchset relies on can be found in Dolby's TrueHD (MLP)
> high-level bitstream description [1]. See sections 4.2.8 and 4.2.9 for
> this commit. Thanks to Hendrik Leppkes for the link.
>
> [1]:
> https://developer.dolby.com/globalassets/technology/dolby-truehd/dolbytruehdhighlevelbitstreamdescription.pdf

LGTM