[gst-devel] webcam & mpegps

[Tim-Philipp Müller]

On Fri, 2011-02-04 at 11:00 +0100, Andres Gonzalez wrote:

> Many thanks for the replies, but still no luck.

In that case, running the pipeline with GST_DEBUG is often a good idea,
to see if anything suspicious pops up, e.g.:

 $ GST_DEBUG=*:2 gst-launch-0.10 ....
 $ GST_DEBUG=*:3 gst-launch-0.10 ....
 $ GST_DEBUG=*:4 gst-launch-0.10 ....

etc.

> /GstPipeline:pipeline0/GstFFMpegCsp:ffmpegcsp0.GstPad:src: caps = 
> video/x-raw-yuv, format=(fourcc)I420, width=(int)640, height=(int)480, 
> interlaced=(boolean)false, framerate=(fraction)22/1
> /GstPipeline:pipeline0/GstFFMpegCsp:ffmpegcsp0.GstPad:sink: caps = 
> video/x-raw-yuv, format=(fourcc)I420, width=(int)640, height=(int)480, 
> interlaced=(boolean)false, framerate=(fraction)22/1
> ERROR: del elemento /GstPipeline:pipeline0/GstV4l2Src:v4l2src0: Error en 
> el flujo de datos interno.
> Información adicional de depuración:
> gstbasesrc.c(2574): gst_base_src_loop (): 
> /GstPipeline:pipeline0/GstV4l2Src:v4l2src0:
> streaming task paused, reason not-negotiated (-4)

This means there's a problem with caps negotiation still. ffmpegcsp's
src pad is the last in the pipeline that got caps set on it, that means
ffenc_mpeg2video rejected the input caps.

It looks like this is due to the 22fps framerate. Try adding a

  ... ! videorate ! video/x-raw-yuv,framerate=25/1 ! ffenc_mpeg2video ..

Cheers 
-Tim