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On Wednesday, 18 September 2019 10:10:16 BST Walter Dnes wrote: |
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> I'm trying to do a video+audio capture of my desktop, e.g. a Youtube |
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> video playing, or whatever. I've got video capture working, but not |
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> audio. I've compiled ffmpeg with both "alsa" and "oss" USE flags and |
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> tried the commands... |
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> |
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> ffmpeg -f alsa -ac 2 -i hw:0 -video_size 1920x1080 -framerate 25 -f x11grab |
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> -i :0.0 output.mp4 |
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The above should work, but only if your active audio card has Card ID 0. If |
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your PC uses HDMI as the first card you'll need to adjust /etc/asound.conf |
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accordingly to switch to your analogue audio device, or perhaps try hw:1 in |
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the above incantation instead. |
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Also, check your Mic is not muted with alsamixer, or your desktop GUI |
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equivalent. |
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> ffmpeg -f oss -i /dev/dsp -video_size 1920x1080 -framerate 25 -f x11grab -i |
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> :0.0 output.mp4 |
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I don't have oss experience and as I understand it pre-OSS4 is mono only(?), |
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but again the above ought to work, as long as there is no clash with alsa. |
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You may need jackd to plug in/out the requisite input devices and sinks - too |
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complicated for just a simple audio recording. |
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> In both case the video capture works, and ffmpeg claims to be |
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> capturing audio, but I don't get any audio capture at all. What am I |
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> doing wrong? Any more USE flags to set? |
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Did you try USE="alsa, -speex"? |
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-- |
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Regards, |
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Mick |
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