[Libav-user] H264 stream width and height parameters from live streams

[Sampsa Riikonen]

Hi,

Thanks for the reply.

I infer from it, that there is no routine in the api that would populate 
AVCodecContext on the basis of feeding it sps and pps packets only, right..?

Regards,

Sampsa


On 29.11.2016 13:11, Carl Eugen Hoyos wrote:
> 2016-11-29 12:07 GMT+01:00 Sampsa Riikonen <sampsa.riikonen at iki.fi>:
>
>> When reading AVPackets from a file, it is straightforward to pass correct
>> parameters to the ffmpeg/vdpau decoder, i. e., we call
>>
>> av_format_find_stream_info
>>
>> and get the relevant data to "AVStream(s)".  Then we do:
>>
>> av_codec_parameters_to_context(AVCodecContext,AVStream.codecpar[AVCodecParameters])
>>
>> That populates correct parameters into AVCodecContext, namely,
>> AVCodecContext->width, height, etc.
>>
>> This works also with "raw" H264 streams (i.e., with ".h264" files), that are
>> not "container" formats, such as matroska, etc..
>> .. so the only conclusion is, that "av_format_find_stream_info" does some
>> kind of sps/pps packet parsing, right?
> It calls libavcodec that does sps/pps parsing (this is the reason libavformat
> depends on libavcodec).
>
> Carl Eugen
> _______________________________________________
> Libav-user mailing list
> Libav-user at ffmpeg.org
> http://ffmpeg.org/mailman/listinfo/libav-user