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I want to convert an .mp4 file to an .asf file, but I need to keep the size of the file below 150 mb (the server I need to upload the file to can only take files under 150 mb). Basically I want to recontain the .mp4 in an .asf file. The code I'm using currently is

ffmpeg input.mp4 -c copy output.asf

The command runs, however when I try to play the file on windows media player (I'm on windows xp) I get an error message saying "Windows media player has encountered a problem while playing the file."

Anyone have any idea why this is happening? And what other ways I can accomplish this task?

share|improve this question
Are you able to play the file back on another program (e.g. VLC, Media Player Classic)? – Breakthrough Jul 3 '13 at 16:52
Hard to tell without seeing the full, uncut console output that you get from ffmpeg. Usually, H.264 video is not entirely supported in ASF streams. Can you only upload ASF files? Where are you uploading to? Please edit your question with more info. Thank you. – slhck Jul 3 '13 at 17:26

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