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[solved] Best video format for OpenSesame

kthesingkthesing Posts: 5
edited February 2012 in OpenSesame

I'm trying to create an experiment using short clips of video, but the program drops frames while playing them.

The videos were exported from Adobe Premiere Pro as Microsoft avi files, 25 fps, PAL widescreen. They play just fine in windows media player, but drop frames in OpenSesame. The smallest file I tried was about 4 seconds long and about 14,000 KB, and it still dropped frames. I'm using Windows XP.

I'm just trying to figure out what other format settings I might use in exporting the videos to achieve the best playback in OpenSesame.

Thank you!


  • DanielDaniel Posts: 365
    edited February 2012

    The current video plugin is very picky concerning the video format that is used. You get the best results with flv, avi or mpg files and less good results with wmv, mp4 or mov formats. The latter often result in skipping or judder.

    Considering you are using .avi format, I would expect no problems, but the ones you experience might have the following causes:

    • avi is a extension that is used for various encoding formats: either uncompressed video (the "original" avi), divx, xvid, or, less frequently, the newer h264. It might be that one of these formats which I haven't tested yet also causes problems. Since you have Adobe Premiere Pro (and therefore also Adobe Media Encoder?), you could try re-encoding the videos using a different codec than the uncompressed avi. I found that divx encoded videos have a smooth playback. I can also recommend using .flv (or flash video).

    • The resolution of your movies might be too high. The current video plugin does not use hardware acceleration to playback videos and is therefore limited to playing videos in SD formats. You could try lowering the resolution of your videos and see if playback becomes smoother.

    These are the solutions I could think of thusfar. We are also planning to release a whole new version of this plugin very soon that uses vlc as a backend. Preliminary testing showed that this plugin supports a much wider range of video formats and resolutions. It has not been thoroughly been tested and still in a highly experimental state, so might be a bit buggy, but you can find the current version of it on https://github.com/dschreij/media_player_vlc. Just copy the contents you can download here in a folder called "media_player_vlc" in the opensesame plug-ins directory. The only requirement for it to run is that you have the vlc player installed at its default location. I have not tested it with vlc 2.0 yet though that was released last week, so I recommend you use an older version (1.1.11 or something). If you decide to give this plugin a spin, please let me know your experiences and any problems you might encounter.

    Good luck!

  • kthesingkthesing Posts: 5
    edited 4:57AM

    Thank you so much! I will give it a try and let you know.

  • kthesingkthesing Posts: 5
    edited 4:57AM

    I'm getting an error when I try to append the vlc media player:

    Failed to load plugin 'media_player_vlc'. Error: 'module' object has no attribute 'qtmedia_player_vlc'

  • DanielDaniel Posts: 365
    edited 4:57AM

    That's weird, as qtmedia_player_vlc is included in the source file. Could you give me some more info about your system and the version of OpenSesame you are currently using? How did you install the plugin? It should be placed as a subfolder in the opensesame plugins folder. For examle c:\\plugins\media_player_vlc\media_player_vlc.py (+ rest of contents).

  • kthesingkthesing Posts: 5
    edited 4:57AM

    I installed the plugin at that location, so I have no idea what the issue might be. I ended up exporting the files as flash videos, and they seem to be working just fine with the regular media player. Thank you for your help!

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