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See FFmpeg Filter Documentation: Video Sources for a list of many other video source filters such as smptehdbars.

Using testsrc and sine filters: ffmpeg -f lavfi -i testsrc -f lavfi -i sine -t 10 -c:v libtheora -c:a libvorbis \Ĭhange frame rate and video size the same way as shown above for the color filter. To change it: color=r=24:s=1280x720:d=5.īut who uses Theora anymore? A more modern alternative that likely fills its niche is VP8/VP9 + Vorbis in WebM: -c:v libvpx output.webm. ffmpeg -f lavfi -i color=d=5 -c:v libtheora output.ogvĭefault frame rate is 25 and default video size is 320x240. Generate a 220 Hz sine wave with a 880 Hz beep each second, for 5 seconds: ffmpeg -f lavfi -i sine=f=220:b=4:d=5 -c:a libvorbis output.oga Other somewhat related examples Test toneĪn annoying tone or beeping tone can be made with sine filter. in a real stochastic white noise generator: take a look at the Generator. in higher sample rates: check out our High Definition Audio Test Files page. It starts and stops with a slow fade in / fade out, which is ideal for healthcare use. If you want something different you can do something like: anullsrc=r=48000:cl=mono (or use cl=1 for mono).įor Vorbis in general, avoid the native encoder vorbis if possible libvorbis will provide a better output (although it doesn't really matter with a silent output). in longer durations: download our 15-minute white noise track in mp3 format. You can now use the anullsrc filter instead, and it will work on any OS: ffmpeg -f lavfi -i anullsrc -t 5 -c:a libvorbis output.oggĭefault sample rate is 44100, and default channel layout is stereo.