[FFmpeg-user] hi, problem after install ffmpeg on my mac

Ted Park kumowoon1025 at gmail.com
Wed Feb 26 08:08:44 EET 2020


> I installed ffmpeg on my mac to convert to webm and do a test. 
> The test went well. The problem is that now on my mac when I try to use vlc or quicktime to watch a video, 
> they no longer play audio. 
> I have audio on my computer if I watch a YouTube video, but if I try to see it from my files on my computer, 
> I don't have audio ....? any suggestions?

That had me confused, I thought you meant installing ffmpeg resulted in audio being crippled not only in VLC but also in QuickTime (?!)

> Let me tell you what I did to convert the file:
> ffmpeg -i video.mp4 -c vp9 -b:v 0 -crf 41 newvideo.webm

So the problem is after you convert, there’s no audio in the output file, right?

I am not exactly sure what is happening here, I would expect it to print an error about invalid codec, since you’ve set vp9 for all streams including audio.

Also, if using encoder name “vp9” actually worked, are you maybe using a really old version?

Try updating ffmpeg, probably want libvpx and libopus as well, and re-run that command without specifying codec. I’m pretty sure vp9 and opus are default for webm. 

Or if you can’t update for some reason or want to check if that is actually the problem, you could try specifying codecs per stream, for example set just the video encoder and let the audio default to whatever it is, like -c:v vp9. 

The console output is usually even more helpful in troubleshooting, plus it shows which build you are using. You should include it in along with the command line in thee future. 

Ted Park

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