GNOME Bugzilla – Bug 397419
[oggdemux] ogm video with subtitles stuck on first frame
Last modified: 2009-09-10 08:03:51 UTC
I have a video file in ogm format which fails to play in GStreamer. The audio plays fine, but only the first frame of the video is displayed. MPlayer plays the file fine, ffplay seems to play sound and video too fast and complains about "[mp3 @ 0xb7dc2428]incorrect frame size, invalid new backstep 746". The file is in ogm format, video is XviD, two audio tracks in mp3 and two subtitle tracks in subrip format. If I use ogmdemux to extract the streams, both audio and video can be played. I can make the file available, but it's about 30 MB in size. If I try to make it any smaller, strangely, the playback problems are gone.
If you could indeed make the file available, that would be great and make things much easier for us.
Here it is, http://www.whiz.se/temp/ogm-mp3-xvid.ogm Due to bandwidth and disk space limitations I would prefer to remove it as soon as you have had the opportunity to download it.
Thanks, got it. One of the subtitle streams (the first one, logically) seems to be completely empty, ie. it only has an ogm header packet and then no subtitle content whatsoever. The problem seems to be that oggdemux neither pushes an EOS event for that pad nor newsegment update events, so the textoverlay element that overlays the subtitles on top of the video is stuck waiting for a text buffer to arrive on the text pad.
Created attachment 80711 [details] [review] tentative patch: sends newsegment updates for lagging ogm subtitle streams Tentative patch; probably needs some work; the newsegment parameters might not be entirely right for streams that don't start from 0 (or even for those that do).
IMHO the patch looks good and probably should be committed after freeze. It's the same as what is done in most other demuxers.
commit ec944797e536fc01d5fade91c17e04b3a1c9b9a3 Author: Sebastian Dröge <sebastian.droege@collabora.co.uk> Date: Thu Sep 10 10:02:58 2009 +0200 oggdemux: Handle kate and cmml as sparse streams too commit fd368ccf7e1e18a637b52dfbc39df7e3a2fd75e8 Author: Tim-Philipp Müller <tim.muller@collabora.co.uk> Date: Thu Sep 10 10:00:16 2009 +0200 oggdemux: Better handling of sparse streams by sending segment updates Fixes bug #397419.