img channel

Channel allows you to adjust the value of each colour channel, individually or combined. All values (including hue) are scaled to the range 0 to 1. It defaults to acting on the red, green and blur channels.

--red

Apply changes to the red channel

--green

Apply changes to the green channel.

--blue

Apply changes to the blue channel.

--hue

Apply changes to the hue channel.

--saturation

Apply changes to the saturation channel.

--lightness

Apply changes to the lightness channel.

--brightness

Apply changes to the brightness channel.

--alpha

Apply changes to the alpha channel.

--by <n>

Amount to adjust value by. This is added (give a negative value to subtract) to the value of each pixel in the colour channels selected.

--ratio <n>

Ratio to adjust value by (default: 1.2). This is multiplied to the value of each pixel in the colour channels selected.