After an evaluation, GNOME has moved from Bugzilla to GitLab. Learn more about GitLab.
No new issues can be reported in GNOME Bugzilla anymore.
To report an issue in a GNOME project, go to GNOME GitLab.
Do not go to GNOME Gitlab for: Bluefish, Doxygen, GnuCash, GStreamer, java-gnome, LDTP, NetworkManager, Tomboy.
Bug 724636 - v4l2videodec: VP8 KO with playbin
v4l2videodec: VP8 KO with playbin
Product: GStreamer
Classification: Platform
Component: gst-plugins-good
Other Linux
: Normal normal
: 1.3.1
Assigned To: GStreamer Maintainers
GStreamer Maintainers
Depends on:
Reported: 2014-02-18 12:45 UTC by Hugues Fruchet
Modified: 2014-02-25 21:12 UTC
See Also:
GNOME target: ---
GNOME version: ---

v4l2object: do not emit "parsed" caps for vp8 (1.55 KB, patch)
2014-02-18 12:45 UTC, Hugues Fruchet
committed Details | Review

Description Hugues Fruchet 2014-02-18 12:45:54 UTC
Created attachment 269542 [details] [review]
v4l2object: do not emit "parsed" caps for vp8

VP8 stream not played with v4l2videodec plugin.
Problem is a negotiation issue between matroskademux and v4l2videodec, due to "parsed" emitted in caps by v4l2videodec and not accepted by matroskademux.

It seems that VP8 is not "parseable" (cf Bug 637831), so vp8parse has not been developped.
The proposed patch consist to not emit "parsed" in caps in case of VP8.
Comment 1 Nicolas Dufresne (ndufresne) 2014-02-18 14:36:42 UTC
Right, also endup making the same patch yesterday, I like your solution with the flag, though it not a long term one, since there is work being done to add vp8 parsing.
Comment 2 Sebastian Dröge (slomo) 2014-02-19 20:32:05 UTC
Comment on attachment 269542 [details] [review]
v4l2object: do not emit "parsed" caps for vp8

I think this is ok in general. VP8 is unparseable, you need to get it chunked into frames already.

The VP8 parser support that is going to be added to the codecparser library is expecting one frame per buffer and only extracting information from them. Most likely there will never be a vp8parse element.
Comment 3 Sebastian Dröge (slomo) 2014-02-19 20:32:43 UTC
Nicolas, I'm not merging this patch myself because I know you have quite some changes pending. Please just integrate that into your branch :)
Comment 4 Nicolas Dufresne (ndufresne) 2014-02-19 21:10:34 UTC
yep, thanks, will add up to my branch.
Comment 5 Nicolas Dufresne (ndufresne) 2014-02-25 21:06:42 UTC
Not has elegant, but forgot to replace it in my branch. I'll try and blend you version into this. Though meanwhile the bug is fixed.

commit 82f2bf052add2442244ff1cb553f8861e3dc4857
Author: Nicolas Dufresne <>
Date:   Tue Feb 11 16:27:08 2014 -0500

    v4l2: Don't require parser for VP8
    Until GStreamer has one (see bug722760), we should not require a parser for VP8.
Comment 6 Nicolas Dufresne (ndufresne) 2014-02-25 21:12:43 UTC
Comment on attachment 269542 [details] [review]
v4l2object: do not emit "parsed" caps for vp8

commit a2d00122ed7c6ba57956eddbc3d7b3719da16198
Author: Hugues Fruchet <>
Date:   Tue Feb 25 16:10:54 2014 -0500

    v4l2object: do not emit "parsed" caps for vp8
    VP8 doesn't require parsing (vp8parse doesn't exist, so negotiation with demux fails
    if "parsed" is set in caps).