[FFmpeg-devel] Make ffmpeg.c and ffplay.c use avctx->request_channels

[Benjamin Larsson]

Andreas ?man wrote:
> Hello,
>
> Michael Niedermayer wrote:
>> it is just advisory (=many codecs ignore it currently)
>> codecs which fail hard due to request_chan could be changed ...
>
> Here are four patches.
>
> I believe they should be applied at the same time (not in the same
> commit though).
>
> I've fixed the dca.c and ac3dec.c to interpret reqeust_channels
> in a advisory way.
>
> ffmpeg.c now sets up the resampler after the first frame is decoded.
>
> and the changes to ffplay.c is pretty straight forward.
> I have not been able to make SDL work with more than two channels.
> Also, the man-page says that only mono and stereo is supported.
>
> So, If each maintainer can have a look at these please :)
>
> ------------------------------------------------------------------------
>
> Index: libavcodec/dca.c
> ===================================================================
> --- libavcodec/dca.c	(revision 11202)
> +++ libavcodec/dca.c	(working copy)
> @@ -1159,23 +1159,12 @@
>      avctx->bit_rate = s->bit_rate;
>  
>      channels = s->prim_channels + !!s->lfe;
> -    avctx->channels = avctx->request_channels;
> -    if(avctx->channels == 0) {
> -        avctx->channels = channels;
> -    } else if(channels < avctx->channels) {
> -        av_log(avctx, AV_LOG_WARNING, "DTS source channels are less than "
> -               "specified: output to %d channels.\n", channels);
> -        avctx->channels = channels;
> -    }
> -    if(avctx->channels == 2) {
> +    if(avctx->request_channels == 2 && s->prim_channels > 2) {
> +        channels = 2;
>          s->output = DCA_STEREO;
> -    } else if(avctx->channels != channels) {
> -        av_log(avctx, AV_LOG_ERROR, "Cannot downmix DTS to %d channels.\n",
> -               avctx->channels);
> -        return -1;
>      }
>  
> -    channels = avctx->channels;
> +    avctx->channels = channels;
>      if(*data_size < (s->sample_blocks / 8) * 256 * sizeof(int16_t) * channels)
>          return -1;
>      *data_size = 0;
>   
> ------------------------------------------------------------------------
>
>   
OK.

MvH
Benjamin Larsson