On Tue, Oct 02, 2018 at 23:33:04 +0200, Michael Koch wrote: > As the next step, I want to hear the output live on the speakers. I did > use exactly the same command line as above, but I replaced ffmpeg by > ffplay and I omitted the output file. At the end of the console output > is an error message. Can't ffplay handle two inputs? Why doesn't ffplay > accept the command line that works fine with ffmpeg?
Indeed, ffplay can't handle multiple inputs that way. > C:\Users\mkoch\Desktop\Ultrasonic Live>c://ffmpeg/ffplay -i test_15kHz.mp3 -f > lavfi -i aevalsrc="sin(12000*2*PI*t):c=stereo:s=44100" -filter_complex > "[0]volume=1,highpass=f=12000,highpass=f=12000,highpass=f=12000,highpass=f=12000[sound];[sound][1]amultiply,lowpass=f=10000,lowpass=f=10000,lowpass=f=10000,lowpass=f=10000" But what you can do is to put both your lavfi source as well as the input file into a filter chain. ffmpeg provides the "movie" and "amovie" filter sources for this. So you can probably do (I'm doing this as a wild guess, without testing): $ ffplay -f lavfi "amovie=test_15kHz.mp3[a0]; aevalsrc="sin(12000*2*PI*t):c=stereo:s=44100[a1]; [a0]volume=1,highpass=f=12000,highpass=f=12000,highpass=f=12000,highpass=f=12000[sound];[sound][a1]amultiply,lowpass=f=10000,lowpass=f=10000,lowpass=f=10000,lowpass=f=10000" (I'm not sure whether you need the "graph" option, or what it's even good for.) The "lavfi" input device documentation has some examples. Moritz _______________________________________________ ffmpeg-user mailing list [email protected] http://ffmpeg.org/mailman/listinfo/ffmpeg-user To unsubscribe, visit link above, or email [email protected] with subject "unsubscribe".
