[FFmpeg-cvslog] r15043 - trunk/libavformat/utils.c

[Ronald S. Bultje]

Hi,

On Fri, Aug 29, 2008 at 6:50 PM, Michael Niedermayer <michaelni at gmx.at> wrote:
> On Fri, Aug 29, 2008 at 06:35:53PM -0400, Ronald S. Bultje wrote:
>> On Fri, Aug 29, 2008 at 6:31 PM, Baptiste Coudurier
>> <baptiste.coudurier at smartjog.com> wrote:
>> > Ronald S. Bultje wrote:
>> >> On Fri, Aug 29, 2008 at 6:13 PM, bcoudurier <subversion at mplayerhq.hu> wrote:
>> >>> make has_codec_parameters not returning true when sample_fmt is not set
>> >> [..]
>> >>> @@ -1842,7 +1842,7 @@ static int has_codec_parameters(AVCodecC
>> >>>     int val;
>> >>>     switch(enc->codec_type) {
>> >>>     case CODEC_TYPE_AUDIO:
>> >>> -        val = enc->sample_rate && enc->channels;
>> >>> +        val = enc->sample_rate && enc->channels && enc->sample_fmt != SAMPLE_FMT_NONE;
>> >>>         if(!enc->frame_size &&
>> >>>            (enc->codec_id == CODEC_ID_VORBIS ||
>> >>>             enc->codec_id == CODEC_ID_AAC))
>> >>
>> >> Doesn't this mean, since s_fmt is codec-dependent (and can thus only
>> >> be set by the codec) that we always have to open the codec and that
>> >> demuxer header parsing is never sufficient to pass find_stream_info()?
>> >> If so, I would guess that this is bad.
>> >>
>> >
>> > Video already does that ... see pix_fmt.
>>
>> Once I test video, I would probably have complained about that... :-).
>>
>> More in a broader context, is this wanted (that we always need to open
>> a codec to know this kind of stuff) and what would be an acceptable
>> way to work around it in case of network-streams such as MMS/RTSP?
>
> It should be possible for AVParsers to set it

But that still requires incoming data, right? Here, for all unselected
streams, no data ever comes in. Only that AVStream to which we
subscribe during setup receives data. For the others, we only have the
SDP data and the RM-MDPR header (or in case of MMS, the WMV
streamheader, IIRC).

Ronald