[FFmpeg-devel] [PATCH v3 01/10] channel_layout: add new channel positions supported by xHE-AAC

[Lynne]

On 26/05/2024 22:51, Marton Balint wrote:
> 
> 
> On Sun, 26 May 2024, Lynne via ffmpeg-devel wrote:
> 
>> On 25/05/2024 08:10, Marton Balint wrote:
>>>
>>>
>>>  On Sat, 25 May 2024, Lynne via ffmpeg-devel wrote:
>>>
>>>>  apichanges will be updated upon merging, as well as a version bump.
>>>>  ---
>>>>  libavutil/channel_layout.h | 4 ++++
>>>>  1 file changed, 4 insertions(+)
>>>>
>>>>  diff --git a/libavutil/channel_layout.h b/libavutil/channel_layout.h
>>>>  index 8a078d1601..4e19bbbd9e 100644
>>>>  --- a/libavutil/channel_layout.h
>>>>  +++ b/libavutil/channel_layout.h
>>>>  @@ -79,6 +79,10 @@ enum AVChannel {
>>>>      AV_CHAN_BOTTOM_FRONT_CENTER,
>>>>      AV_CHAN_BOTTOM_FRONT_LEFT,
>>>>      AV_CHAN_BOTTOM_FRONT_RIGHT,
>>>>  +    AV_CHAN_SURROUND_LEFT,
>>>>  +    AV_CHAN_SURROUND_RIGHT,
>>>
>>>  You want to add a channel ID for Surround or Side Surround? Because 
>>> based
>>>  on the subsequent AAC patch you want to add it for side surround, 
>>> but then
>>>  the AV_CHAN_SURROUND name is confusing, since we are mapping 
>>> Surround to
>>>  AV_CHAN_SIDE. So I suggest using AV_CHAN_SIDE_SURROUND_LEFT/RIGHT 
>>> instead.
>>>
>>>>  +    AV_CHAN_TOP_SURROUND_LEFT,
>>>>  +    AV_CHAN_TOP_SURROUND_RIGHT,
>>>
>>>  You will need to extend the channel_names[] array in 
>>> channel_layout.c with
>>>  the newly added channel IDs.
>>
>>
>> Thanks, changed locally.
>> Planning on merging this in 2 days unless there are more comments.
> 
> Can you post the updated version of this patch? It is not entirely clear 
> what you added, or e.g. what abbriviation you planning to use for the 
> new channel IDs. Also I noticed one more thing, you also need to add the 
> AV_CH_* variants for the new IDs.

Sure, posted.
I went with exactly what you wrote.

> 3 days for new API such as this is a bit short, and if your AAC patches 
> depend on it, I suggest you wait a few more days.

...its an enum entry. Do you want a design document and a proposal?
You could talk to the person who did the research about it, JEEB.
Why wait at all? There's only you and JEEB that care about channel 
layouts, you can review it and give it an LGTM. There's no reason to 
wait for days, that is not how reviewing is supposed to work.

The decoder doesn't depend on it, I have fallback code. I've been 
waiting for the channel layout situation to be resolved.
-------------- next part --------------
A non-text attachment was scrubbed...
Name: OpenPGP_0xA2FEA5F03F034464.asc
Type: application/pgp-keys
Size: 624 bytes
Desc: OpenPGP public key
URL: <https://ffmpeg.org/pipermail/ffmpeg-devel/attachments/20240526/99a5e1b9/attachment.key>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: OpenPGP_signature.asc
Type: application/pgp-signature
Size: 236 bytes
Desc: OpenPGP digital signature
URL: <https://ffmpeg.org/pipermail/ffmpeg-devel/attachments/20240526/99a5e1b9/attachment.sig>