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I am trying to convert a .mov to an uncompressed .avi with ffmpeg. As I want no quality loss, I am using the following ffmpeg command:

ffmpeg -i -vcodec copy -y toto.avi

The convertion works perfectly (the video works in VLC) except that when I am opening the file with virtualdub I get a black screen.

In VirtualDub, under file information I get the following:

Frame size: 800x600, 30.000fps
Length: 802 frames
Decompressor: Internal DIB decoder

If I am not specifying the -pix_fmt and -vcodec arguments, ffmpeg convert to mpeg-4 and yuv420p but I am loosing on the quality as my file shrunk to about 400Mo to 1Mo but the video works in virtualdub and this time the Decompressor is set to ffdshow Video Codec (FMP4). I doubt this is a ffdshow as I had another video working perfectly with the internal DIB decoder.

Any idea, to get the image in virtualdub?

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migrated from May 28 '13 at 13:26

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up vote 0 down vote accepted

In first instance you are just changing the media container, but not the codec. Probably VirtualDub can not decode that codec which is in your original container. You can transcode the codec to MPEG-4 with the -q:v set to 1, this results in good enough quality.

ffmpeg -i -q:v 1 -vcodec mpeg4 -y toto.avi
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The original video is in rawvideo and pal8 for the pixel format... I get a warning about -qscale 1 : Please use -q:a or -q:v, -qscale is ambiguous I switch to -q:v 1 – TazgerO May 28 '13 at 9:24
Sorry, it is -q:v indeed, changed it in my answer. Since you say the data is rawvideo already, it seems VirtualDub can't "decode" the raw data this way. VLC does, since it can play almost every video. I can possibly not help you further using the raw video, since I never worked with VirtualDub. – Nick van Tilborg May 28 '13 at 9:46
Is there a way to extract video information from the original mov? – TazgerO May 28 '13 at 9:51
You can use ffprobe -i to analyze your videofile and extract all data from the command line. – Nick van Tilborg May 28 '13 at 10:01
Sry, without the -i, only ffprobe – Nick van Tilborg May 28 '13 at 10:09

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