I summarize here the results of converting from webm to mp4 using the many command line options suggested. I was able to convert by ffmpeg -i video.webm -strict experimental video.mp4. Or add -strict experimental (or the alias -strict -2) if you are stuck with outdated ffmpeg.Use a newer ffmpeg as Opus in MP4 is no longer experimental in newer ffmpeg versions.
If you get this error: opus in MP4 support is experimental, add '-strict -2' if you want to use it.Ĭould not write header for output file #0 (incorrect codec parameters ?): Experimental feature If you get error: "opus in MP4 support is experimental" No re-encoding occurs, so no quality is lost and the process is very fast. This will copy the VP9/VP8 video and Opus/Vorbis audio from WebM to MP4. If you want to stream copy (re-mux) and avoid re-encoding: ffmpeg -i input.webm -c copy output.mp4 So your output mp4 file info ( ffmpeg -i.
You configure ffmpeg to generate new pts (a.k.a Presentation TimeStamp) for each frame and you set the target frame-rate to 24. So by calling : ffmpeg -fflags +genpts -i 1.webm -r 24 1.mp4 The encoder generate a different result, 16k tbn, 1k tbc (default) As your input file report a strange frame rate value 1k fps coming from the tbs and tbr value (look here for their definition)