[FFmpeg-devel] [PATCH 2/2] avcodec/liblc3enc: don't force unspec channel layouts

[James Almer]

On 4/4/2024 1:45 PM, Stefano Sabatini wrote:
> On date Thursday 2024-04-04 13:29:36 -0300, James Almer wrote:
>> We only care about channel count. Layout details will be ignored either way.
>>
>> Signed-off-by: James Almer <jamrial at gmail.com>
>> ---
>>   libavcodec/liblc3enc.c | 8 +++++---
>>   1 file changed, 5 insertions(+), 3 deletions(-)
>>
>> diff --git a/libavcodec/liblc3enc.c b/libavcodec/liblc3enc.c
>> index 63d1645b10..5f8169a0cf 100644
>> --- a/libavcodec/liblc3enc.c
>> +++ b/libavcodec/liblc3enc.c
>> @@ -61,6 +61,11 @@ static av_cold int liblc3_encode_init(AVCodecContext *avctx)
>>                  "Unsupported frame duration %.1f ms.\n", frame_us / 1000.f);
>>           return AVERROR(EINVAL);
>>       }
>> +    if (channels < 0 || channels > ENCODER_MAX_CHANNELS) {
>> +        av_log(avctx, AV_LOG_ERROR,
>> +               "Unsupported channel count %d. Should be 1 or 2\n", channels);
>> +        return AVERROR(EINVAL);
>> +    }
>>   
>>       hr_mode |= srate_hz > 48000;
>>       hr_mode &= srate_hz >= 48000;
>> @@ -195,9 +200,6 @@ const FFCodec ff_liblc3_encoder = {
>>       .p.type         = AVMEDIA_TYPE_AUDIO,
>>       .p.id           = AV_CODEC_ID_LC3,
>>       .p.capabilities = AV_CODEC_CAP_DR1 | AV_CODEC_CAP_DELAY,
> 
>> -    .p.ch_layouts = (const AVChannelLayout[])
>> -        { { AV_CHANNEL_ORDER_UNSPEC, 1 },
>> -          { AV_CHANNEL_ORDER_UNSPEC, 2 }, { 0 } },
> 
> shouldn't this be equivalent?
> 
> Should be good anyway.

No, because if you pass it a mono or stereo layout, the generic encode 
code will reject it, whereas after this change it will work because the 
encoder will only cares about channel count, not overall layout.