[Bug 759976] New: Flushing mpeg2dec during seek breaks libmpeg2 decoding

["GStreamer" (GNOME Bugzilla)]

https://bugzilla.gnome.org/show_bug.cgi?id=759976

Bug ID: 759976
Summary: Flushing mpeg2dec during seek breaks libmpeg2 decoding
Classification: Platform
Product: GStreamer
Version: 1.6.2
OS: Linux
Status: NEW
Severity: normal
Priority: Normal
Component: gst-plugins-ugly
Assignee: gstreamer-***@lists.freedesktop.org
Reporter: ***@codeweavers.com
QA Contact: gstreamer-***@lists.freedesktop.org
GNOME version: ---

(Possibly a duplicate of https://bugzilla.gnome.org/show_bug.cgi?id=723603 ?)

OS: Arch Linux (up to date as of yesterday)
libmpeg2 package version 0.5.1-5

I have two mpg files that fail to seek in Totem. They are distributed with the
Steam version of Grand Theft Auto: Vice City.

[***@aeikum movies]$ file *
GTAtitles.mpg: MPEG sequence, v1, system multiplex
Logo.mpg: MPEG sequence, v1, system multiplex
[***@aeikum movies]$ md5sum *
d469239863d8dd5d27a758ec407d3e5a GTAtitles.mpg
5d5ff3db65ba37a0d5f0474a96ac51ea Logo.mpg

Totem successfully plays the videos. However, if you try to seek any length,
Totem will display a dialog saying, "No valid frames decoded before end of
stream" and quit playing the video. Seeking is possible with VLC.

A little extra debug printing in gst-plugins-ugly shows the problem occurs
after executing gst_mpeg2dec_flush during the seek operation:

mpeg2dec gstmpeg2dec.c:1103:gst_mpeg2dec_handle_frame:<mpeg2dec1> parse state 0
mpeg2dec gstmpeg2dec.c:1103:gst_mpeg2dec_handle_frame:<mpeg2dec1> parse state 7
mpeg2dec gstmpeg2dec.c:1103:gst_mpeg2dec_handle_frame:<mpeg2dec1> parse state 4
mpeg2dec gstmpeg2dec.c:974:handle_picture:<mpeg2dec1> stride
mpeg2dec gstmpeg2dec.c:1103:gst_mpeg2dec_handle_frame:<mpeg2dec1> parse state 0
mpeg2dec gstmpeg2dec.c:246:gst_mpeg2dec_flush:<mpeg2dec1> flushing decoder
mpeg2dec gstmpeg2dec.c:246:gst_mpeg2dec_flush:<mpeg2dec1> flushing decoder
mpeg2dec gstmpeg2dec.c:246:gst_mpeg2dec_flush:<mpeg2dec1> flushing decoder
mpeg2dec gstmpeg2dec.c:246:gst_mpeg2dec_flush:<mpeg2dec1> flushing decoder
mpeg2dec gstmpeg2dec.c:1103:gst_mpeg2dec_handle_frame:<mpeg2dec1> parse state 0
mpeg2dec gstmpeg2dec.c:1103:gst_mpeg2dec_handle_frame:<mpeg2dec1> parse state 0
mpeg2dec gstmpeg2dec.c:1103:gst_mpeg2dec_handle_frame:<mpeg2dec1> parse state 0
mpeg2dec gstmpeg2dec.c:1103:gst_mpeg2dec_handle_frame:<mpeg2dec1> parse state 0
mpeg2dec gstmpeg2dec.c:1103:gst_mpeg2dec_handle_frame:<mpeg2dec1> parse state 0

States {0,7,4} are normal operation. After flushing, mpeg2_parse always returns
STATE_BUFFER(== 0) no matter how much data is fed to mpeg2_buffer.
gst_mpeg2dec_flush executes mpeg2_reset and mpeg2_skip.

Attached is a GST_DEBUG=9 log of the Totem session, trimmed to the first 600000
lines (expands to 112 MB).

["GStreamer" (GNOME Bugzilla)]

https://bugzilla.gnome.org/show_bug.cgi?id=759976

--- Comment #1 from Andrew Eikum <***@codeweavers.com> ---
Created attachment 318013
--> https://bugzilla.gnome.org/attachment.cgi?id=318013&action=edit
Trimmed GST_DEBUG log of Totem failing to seek

The log was too big, so I've uploaded a log without refcounting and trimmed to
200000 lines. It expands to 40 MB.

["GStreamer" (GNOME Bugzilla)]

https://bugzilla.gnome.org/show_bug.cgi?id=759976

--- Comment #2 from Andrew Eikum <***@codeweavers.com> ---
I also see this problem with the two videos available here:

http://fgouget.free.fr/tmp/wine-test-videos/daytona_crw.mpg
http://fgouget.free.fr/tmp/wine-test-videos/Ikea_Tidy_up_2_11.mpg

From:

https://bugs.winehq.org/show_bug.cgi?id=17448#c14

["GStreamer" (GNOME Bugzilla)]

https://bugzilla.gnome.org/show_bug.cgi?id=759976

--- Comment #3 from Andrew Eikum <***@codeweavers.com> ---
Another user was able to confirm this with 1.6.2 on their machine, so it isn't
an issue unique to Arch or my setup.

["GStreamer" (GNOME Bugzilla)]

https://bugzilla.gnome.org/show_bug.cgi?id=759976

--- Comment #4 from Andrew Eikum <***@codeweavers.com> ---
I tried reverting this commit on top of 1.6.2:

commit 22b3a60dbd393b9f82d411efc027f20992904b69
Author: Sebastian Dröge <***@circular-chaos.org>
Date: Thu Aug 15 15:30:31 2013 +0200

mpeg2dec: Fix mpeg2_reset() calls



Totem no longer shows the error on seeking. However, the mpeg usually decoding
seems to go poorly, as if it never finds another key frame, but not always.
Sometimes (maybe 1 in 10 seeks) it works correctly after a seek.

["GStreamer" (GNOME Bugzilla)]

https://bugzilla.gnome.org/show_bug.cgi?id=759976

***@yahoo.fr changed:

What |Removed |Added
----------------------------------------------------------------------------
CC| |***@yahoo.fr

["GStreamer" (GNOME Bugzilla)]

https://bugzilla.gnome.org/show_bug.cgi?id=759976

Tim-Philipp Müller <***@zen.co.uk> changed:

What |Removed |Added
----------------------------------------------------------------------------
CC| |***@zen.co.uk
Summary|Flushing mpeg2dec during |mpeg2dec: Flushing during
|seek breaks libmpeg2 |seek breaks libmpeg2
|decoding |decoding

["GStreamer" (GNOME Bugzilla)]

https://bugzilla.gnome.org/show_bug.cgi?id=759976

GStreamer system administrator <***@gstreamer.net> changed:

What |Removed |Added
----------------------------------------------------------------------------
Status|NEW |RESOLVED
Resolution|--- |OBSOLETE

--- Comment #5 from GStreamer system administrator <***@gstreamer.net> ---
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