showfreqs

Convert input audio to video output representing the audio power spectrum. Audio amplitude is on Y-axis while frequency is on X-axis.

The filter accepts the following options:

'size, s'

Specify size of video. For the syntax of this option, check the . Default is 1024x512.

'mode'

Set display mode. This set how each frequency bin will be represented.

It accepts the following values:

'line'
'bar'
'dot'

Default is bar.

'ascale'

Set amplitude scale.

It accepts the following values:

'lin'

Linear scale.

'sqrt'

Square root scale.

'cbrt'

Cubic root scale.

'log'

Logarithmic scale.

Default is log.

'fscale'

Set frequency scale.

It accepts the following values:

'lin'

Linear scale.

'log'

Logarithmic scale.

'rlog'

Reverse logarithmic scale.

Default is lin.

'win_size'

Set window size.

It accepts the following values:

'w16'
'w32'
'w64'
'w128'
'w256'
'w512'
'w1024'
'w2048'
'w4096'
'w8192'
'w16384'
'w32768'
'w65536'

Default is w2048

'win_func'

Set windowing function.

It accepts the following values:

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

Default is hanning.

'overlap'

Set window overlap. In range [0, 1]. Default is 1, which means optimal overlap for selected window function will be picked.

'averaging'

Set time averaging. Setting this to 0 will display current maximal peaks. Default is 1, which means time averaging is disabled.

'colors'

Specify list of colors separated by space or by '|' which will be used to draw channel frequencies. Unrecognized or missing colors will be replaced by white color.

'cmode'

Set channel display mode.

It accepts the following values:

'combined'
'separate'

Default is combined.

'minamp'

Set minimum amplitude used in log amplitude scaler.