avdec_g722

[Tim Müller]

Hi Thomas,
  
> my issue come down to decoding this input file.  I pared down the
> decoding to the following pipeline:
>  
> gst-launch-1.0 filesrc location=./testing.g722 ! audio/G722 !
> avdec_g722 ! fakesink
>  
> and still get an error
>  
> ERROR: from element /GstPipeline:pipeline0/GstFileSrc:filesrc0:
> Internal data stream error.
>  
> There is some additional information that gstbasesrc.c (3055)
> streaming stopped, reason error (-5)
>  
> Running in higher debug levels I get more information that in
> gstaudiodecoder.c (2199) indicates that it is an unsupported format. 
> The code seems to fail when checking if we should change from a byte
> to time format (gstaudiodecoder.c:2184) that either the
> context.d_estimate_rate is false, or the format couldn’t be converted
> from a bytes format to a time format.
>  
> Where do I look now for the cause of this error?  I would think that
> a file created with the avenc_g722 would be able to be decoded with
> the avdec_g722.  Am I missing something fundamental?

Two things:

1) a "not-negotiated" error usually indicates a problem with the caps
(media format signalling): either caps are wrong, incomplete or there
were no caps signalled. In this case the problem is likely that filesrc
just outputs data without any caps, and the decoder wants caps being
signalled. You could fix this by adding a capsfilter with the right
G722 caps, but:

2) the audio decoder probably wants the data being fed to it being
nicely packetised and timestamped. Typically such data will be
packetised by a container (e.g. matroska, quicktime) or transport
(RTP). You could try adding a matroskamux to your creation pipeline,
and a matroskademux to your playback pipeline, otherwise the decoder
will be fed audio data in chunks of 4kB (or whatever), which is
probably not right.

Cheers
 Tim

-- 
Tim Müller, Centricular Ltd - http://www.centricular.com