Convert input audio to a video output, representing the samples waves.
The filter accepts the following options:
- size, s
-
Specify the video size for the output. For the syntax of this option, check the "Video size" section in the ffmpeg-utils manual. Default value is "600x240".
- mode
-
Set display mode.
Available values are:
- point
-
Draw a point for each sample.
- line
-
Draw a vertical line for each sample.
- p2p
-
Draw a point for each sample and a line between them.
- cline
-
Draw a centered vertical line for each sample.
Default value is
point
. - n
-
Set the number of samples which are printed on the same column. A larger value will decrease the frame rate. Must be a positive integer. This option can be set only if the value for rate is not explicitly specified.
- rate, r
-
Set the (approximate) output frame rate. This is done by setting the option n. Default value is "25".
- split_channels
-
Set if channels should be drawn separately or overlap. Default value is 0.
Examples
-
Output the input file audio and the corresponding video representation at the same time:
amovie=a.mp3,asplit[out0],showwaves[out1]
-
Create a synthetic signal and show it with showwaves, forcing a frame rate of 30 frames per second:
aevalsrc=sin(1*2*PI*t)*sin(880*2*PI*t):cos(2*PI*200*t),asplit[out0],showwaves=r=30[out1]