colorchannelmixer

Adjust video input frames by re-mixing color channels.

This filter modifies a color channel by adding the values associated to the other channels of the same pixels. For example if the value to modify is red, the output value will be:

red=red*rr + blue*rb + green*rg + alpha*ra

The filter accepts the following options:

rr

rg

rb

ra

Adjust contribution of input red, green, blue and alpha channels for output red channel. Default is 1 for rr, and 0 for rg, rb and ra.

gr

gg

gb

ga

Adjust contribution of input red, green, blue and alpha channels for output green channel. Default is 1 for gg, and 0 for gr, gb and ga.

br

bg

bb

ba

Adjust contribution of input red, green, blue and alpha channels for output blue channel. Default is 1 for bb, and 0 for br, bg and ba.

ar

ag

ab

aa

Adjust contribution of input red, green, blue and alpha channels for output alpha channel. Default is 1 for aa, and 0 for ar, ag and ab.

Allowed ranges for options are [-2.0, 2.0].

pc

Set preserve color mode. The accepted values are:

‘none’

Disable color preserving, this is default.

‘lum’

Preserve luminance.

‘max’

Preserve max value of RGB triplet.

‘avg’

Preserve average value of RGB triplet.

‘sum’

Preserve sum value of RGB triplet.

‘nrm’

Preserve normalized value of RGB triplet.

‘pwr’

Preserve power value of RGB triplet.

pa

Set the preserve color amount when changing colors. Allowed range is from [0.0, 1.0]. Default is 0.0, thus disabled.

Examples

• Convert source to grayscale:

  colorchannelmixer=.3:.4:.3:0:.3:.4:.3:0:.3:.4:.3
  

• Simulate sepia tones:

  colorchannelmixer=.393:.769:.189:0:.349:.686:.168:0:.272:.534:.131