I'm am trying to create an new AVOutputFormat the uses an Mjpeg video codec in an avi container, the problem I am running into is that my header info is being corrupted. I'm currently using guess_format( NULL, "filename.avi" NULL ) to get the avi default format and then I set the audio codec to CODEC_ID_NONE and the video codec to CODEC_ID_MJPEG. This compiles and works to a certain extent sinceI can open the files recorded in this format in VirtualDubMod, but VDB detects that the header info is corrupt and has to repair the file so it can be viewed. Does any know how I can modify the AVOutputFormat::write_header?