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OpenGL OpenGL & AVI/MPEG playback problem

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Greetings, In my current OpenGL application, I need to be able to play an AVI/MPEG file at any time (basic 2D rendering of the video, no need for any 3D video-texture). My problem is that when I do play the AVI file, I''m loosing some of my textures (both in software rendering and with my GeForce 2 MX OpenGL driver). I''ve tried to play the video in a separate process too, the results are the same. I''m using DirectShow to render the video file in a separate window, displayed just over the OpenGL rendering window. This seems to conflict with the OpenGL drivers. But when I launch the AVI from the Mediaplayer while my OpenGL app is running, I don''t loose any texture. Do you know how I could solve this problem ? Thanks, Emmanuel.

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I don''t know if you''ve found this, but there''s a recent NeHe tutorial dealing with video. I haven''t gone throught it yet (I''ve got far more important things at the moment to do ), but it should help you out. I think it uses Video For Windows instead of DirectShow.

You can find it at http://nehe.gamedev.net/tutorials/lesson36.asp

I seem to remember somebody saying that it''s generally a bad idea to use OpenGL and a MS rendering API together...

Simon Wilson,
XEOS Digital Development

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Greetings,

Sure, I took a look at this excellent tutorial, but it mainly
explains how to render a video to a texture. In my case, I
want to render the video + sound streams in my window.

After some more experiments, it appears that even if I launch
the Mediaplayer application while my app is running, I also
loose textures (either in software & hardware mode) !!!

I''ve found a workaround to my problem: after the video has finished to play, I recreate the OpenGL rendering context.
But this involves reloading all the textures, which can be
a pain and is really not elegant ... But it works.

If someone has a better way to do it, please let me know.

Thanks,
Emmanuel.

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