showwaves

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 (ffmpeg-utils)"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.

colors

Set colors separated by ’|’ which are going to be used for drawing of each channel.

scale

Set amplitude scale.

Available values are:

‘lin’

Linear.

‘log’

Logarithmic.

‘sqrt’

Square root.

‘cbrt’

Cubic root.

Default is linear.

draw

Set the draw mode. This is mostly useful to set for high n.

Available values are:

‘scale’

Scale pixel values for each drawn sample.

‘full’

Draw every sample directly.

Default value is scale.

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]