# Problem playing DualDiscs.mov - playback doesn't show the first ~2 seconds **URL:** \ **Category:** Uncategorized\ **Created:** [February 28, 2012, 6:38pm UTC](https://psychtoolbox.discourse.group/t/problem-playing-dualdiscs-mov-playback-doesn-39-t-show-the-first-2-seconds/450 "2012-02-28T18:38:30Z")\ **Posts on this page:** 1\ **Page:** 1
**Author:** ![Allen\_Ingling](https://avatars.discourse-cdn.com/v4/letter/a/a183cd/32.png) [@Allen\_Ingling](https://psychtoolbox.discourse.group/u/Allen_Ingling)\ **Post date:** [February 28, 2012, 6:38pm UTC](https://psychtoolbox.discourse.group/t/problem-playing-dualdiscs-mov-playback-doesn-39-t-show-the-first-2-seconds/450/1 "2012-02-28T18:38:30Z")
Background motivation for this question: We are experiencing major platform-dependent problems opening and playing movies in Psychtoolbox, and we would really appreciate some help.  In the course of trying to establish reliable movie behavior, we've tried many combinations of software:  Win7/WinXP (Gstreamer Winbuilds 0.10.7 beta and 0.10.6 stable on each), and Ubuntu 11.10 64-bit and 32-bit, and Ubuntu 10.04, both Matlab and Octave.  We have tried 2 different video cards and also a separate laptop system.  But on all these systems we have varying file-dependent problems where our files won't open, or will open 1 time but not the 2nd time in a script, or we have problems with short bits of sound being dropped.  So we are trying to establish a solid baseline of proper movie playback on 64-bit Ubuntu 11.10.  For now we are focusing on DualDiscs.mov.  Since our problems with our own movies and operating systems have been so varied, I will limit the rest of this question to 1 specific problem on 1 specific system:   playback of the standard DualDiscs.mov that comes with PTB, on 64-bit Ubuntu 11.10.   The problem is: When playing DualDiscs.mov in Matlab or Octave, playback starts near the end of the movie, 2-2.5 seconds into it, instead of at the beginning as expected.  I attached a .png that shows about where the movie starts.  To demonstrate the movie timing for you, I have supplied the output a modified version of PlayMoviesWithoutGapDemoOSX that calls Screen('GetTimeIndex') and prints it before each call to Screen('GetMovieImage'...).  It is in the attached logfile:  "log-gstreamer.txt".  You can see the time of the first frame output near the lines that start with "ITER=1" "ITER=2" etc.  I have also attached modified demo file that created this output: PlayMoviesWithoutGapDemoOSX\_gettimeindex.m.  Note that we use Screen('Preference', 'Verbosity', 10) in the logfile.  We can reproduce this problem on this machine using 2 different video cards:  Nvidia GeForce GTS 450 and Nvidia GeForce 6800.  Details about the specific system that generated the logfile output are at the end of this message.  And I have also reproduced the behavior on a completely separate system: a i5-2435M Intel-based laptop that uses an Intel integrated graphics controller (64-bit Ubuntu 11.10, using Octave 3.2.4, haven't tried Matlab).  We can play DualDiscs.mov fine outside of Psychtoolbox using totem or vlc, on both the desktop system and the laptop system. One extra request:  Mario, can you supply standard movies for testing that are known to play with no problems in Psychtoolbox, but in formats other than what's used by DualDiscs.mov?  For example, the formats that correspond to .avi, .mp4, etc?  For this testing purpose, we would prefer not to convert DualDiscs.mov to other formats ourselves (not even with ffmpeg -strict) since we don't know yet if some of our problems are caused by the movie encoders we have tried! Thanks for any help you can give! Tim Edmondson -- The attached logfile log-gstreamer.txt was generated by Matlab, with the following system configuration: Ubuntu: 11.10 64-bit Linux machine 3.0.0-16-generic #28-Ubuntu SMP Fri Jan 27 17:44:39 UTC 2012 x86\_64 x86\_64 x86\_64 GNU/Linux CPU: Intel Core i7-2600 quad-core 3.40GHz Graphics card: Nvidia GeForce GTS 450 Graphics driver: nvidia-current-updates 280.13-0ubuntu5 Matlab: 7.13.0.564 (R2011b) Psychtoolbox: PsychtoolboxVersion 3.0.9 - Flavor: beta - Corresponds to SVN Revision 2450 gstreamer: gstreamer0.10-ffmpeg 0.10.12-1ubuntu1 gstreamer0.10-plugins-ugly 0.10.18-3ubuntu1 gstreamer0.10-plugins-bad 0.10.22-2ubuntu4 gstreamer0.10-plugins-bad-multiverse 0.10.21-1 and other various plugins from the standard repositories