I want to change the audio of a video but the audio is longer than the video, when I mux them (ffmpeg -i "audio.m4a" -i "video.webm" -acodec copy -vcodec copy "out.mkv") the video that comes out doesn't play properly in Media Player Classic/VLC with the duration of the video hanging on the last second while continuing to play audio, and the audio at the end doesn't get heard on Youtube/Dailymotion at all :(

(I want to do this without encode/compress/transcode the video again, to not lose quality, this is really important for me)

I read about how to concatenate (join) another video like a title screen and the original video in the ffmpeg FAQ by using cat file1.mpg file2.mpg > newfile.mpg but the video format I want to do this with is "VP90 29.97fps profile 0, yuv420p" (as used by Youtube) so I guess that is one solution if I there is a program that can make videos in a similar format, unless there is a better way to simply extend the video by making the last frame stay constant?

Another issue is I don't actually know what open source program as an alternative to Sony Vegas etc that I would use to make a simple single image video to join to extend the video because I've never made a video before :s (I also have a lot of ultra-high quality uncompressed avi FRAPS videos from before nvidia drivers supported recording I would like to put on dailymotion and youtube with losing as little quality as possible) Thank you so much for anyone that can help

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  • How did you get or make the webm? – Gyan Dec 6 at 5:22

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