showspectrum


Convert input audio to a video output, representing the audio frequency spectrum.

The filter accepts the following options:

'size, s'

Specify the video size for the output. For the syntax of this option, check the . Default value is 640x512.

'slide'

Specify how the spectrum should slide along the window.

It accepts the following values:

'replace'

the samples start again on the left when they reach the right

'scroll'

the samples scroll from right to left

'fullframe'

frames are only produced when the samples reach the right

'rscroll'

the samples scroll from left to right

Default value is replace.

'mode'

Specify display mode.

It accepts the following values:

'combined'

all channels are displayed in the same row

'separate'

all channels are displayed in separate rows

Default value is 'combined'.

'color'

Specify display color mode.

It accepts the following values:

'channel'

each channel is displayed in a separate color

'intensity'

each channel is displayed using the same color scheme

'rainbow'

each channel is displayed using the rainbow color scheme

'moreland'

each channel is displayed using the moreland color scheme

'nebulae'

each channel is displayed using the nebulae color scheme

'fire'

each channel is displayed using the fire color scheme

'fiery'

each channel is displayed using the fiery color scheme

'fruit'

each channel is displayed using the fruit color scheme

'cool'

each channel is displayed using the cool color scheme

'magma'

each channel is displayed using the magma color scheme

'green'

each channel is displayed using the green color scheme

'viridis'

each channel is displayed using the viridis color scheme

'plasma'

each channel is displayed using the plasma color scheme

'cividis'

each channel is displayed using the cividis color scheme

'terrain'

each channel is displayed using the terrain color scheme

Default value is 'channel'.

'scale'

Specify scale used for calculating intensity color values.

It accepts the following values:

'lin'

linear

'sqrt'

square root, default

'cbrt'

cubic root

'log'

logarithmic

'4thrt'

4th root

'5thrt'

5th root

Default value is 'sqrt'.

'fscale'

Specify frequency scale.

It accepts the following values:

'lin'

linear

'log'

logarithmic

Default value is 'lin'.

'saturation'

Set saturation modifier for displayed colors. Negative values provide alternative color scheme. 0 is no saturation at all. Saturation must be in [-10.0, 10.0] range. Default value is 1.

'win_func'

Set window function.

It accepts the following values:

'rect'
'bartlett'
'hann'
'hanning'
'hamming'
'blackman'
'welch'
'flattop'
'bharris'
'bnuttall'
'bhann'
'sine'
'nuttall'
'lanczos'
'gauss'
'tukey'
'dolph'
'cauchy'
'parzen'
'poisson'
'bohman'

Default value is hann.

'orientation'

Set orientation of time vs frequency axis. Can be vertical or horizontal. Default is vertical.

'overlap'

Set ratio of overlap window. Default value is 0. When value is 1 overlap is set to recommended size for specific window function currently used.

'gain'

Set scale gain for calculating intensity color values. Default value is 1.

'data'

Set which data to display. Can be magnitude, default or phase.

'rotation'

Set color rotation, must be in [-1.0, 1.0] range. Default value is 0.

'start'

Set start frequency from which to display spectrogram. Default is 0.

'stop'

Set stop frequency to which to display spectrogram. Default is 0.

'fps'

Set upper frame rate limit. Default is auto, unlimited.

'legend'

Draw time and frequency axes and legends. Default is disabled.

The usage is very similar to the showwaves filter; see the examples in that section.