Modify the hue and/or the saturation of the input.

This filter accepts the following optional named options:

h

Specify the hue angle as a number of degrees. It accepts a float number or an expression, and defaults to 0.0.

H

Specify the hue angle as a number of degrees. It accepts a float number or an expression, and defaults to 0.0.

s

Specify the saturation in the [-10,10] range. It accepts a float number and defaults to 1.0.

The h, H and s parameters are expressions containing the following constants:

n

frame count of the input frame starting from 0

pts

presentation timestamp of the input frame expressed in time base units

r

frame rate of the input video, NAN if the input frame rate is unknown

t

timestamp expressed in seconds, NAN if the input timestamp is unknown

tb

time base of the input video

The options can also be set using the syntax: hue:saturation

In this case hue is expressed in degrees.

Some examples follow:

• Set the hue to 90 degrees and the saturation to 1.0:

  hue=h=90:s=1

• Same command but expressing the hue in radians:

  hue=H=PI/2:s=1

• Same command without named options, hue must be expressed in degrees:

  hue=90:1

• Note that "h:s" syntax does not support expressions for the values of h and s, so the following example will issue an error:

  hue=PI/2:1

• Rotate hue and make the saturation swing between 0 and 2 over a period of 1 second:

  hue="H=2*PI*t: s=sin(2*PI*t)+1"

• Apply a 3 seconds saturation fade-in effect starting at 0:

  hue="s=min(t/3\,1)"

  The general fade-in expression can be written as:

  hue="s=min(0\, max((t-START)/DURATION\, 1))"

• Apply a 3 seconds saturation fade-out effect starting at 5 seconds:

  hue="s=max(0\, min(1\, (8-t)/3))"

  The general fade-out expression can be written as:

  hue="s=max(0\, min(1\, (START+DURATION-t)/DURATION))"