kiteplayer-core/io.github.yuroyami.kiteplayer/VideoAdjustments

VideoAdjustments

data class VideoAdjustments(val brightness: Float = 0.0f, val contrast: Float = 1.0f, val saturation: Float = 1.0f, val hueDegrees: Float = 0.0f, val gamma: Float = 1.0f)

The picture controls a viewer expects from a real player: brightness, contrast, saturation, hue and gamma, live, without touching the decoder (mpv's eq). The engine owns the value and every attached renderer is told it, exactly like VideoScale; the renderers apply it per drawn frame, which is why a change is instant and free of pipeline work.

Brightness, contrast, saturation and hue compose into a single affine colour transform, and toColorMatrix is the ONE place that transform is written down, so no two renderers can disagree about what saturation means. gamma is a power curve, which no matrix can express, so it is a second step that runs on the matrix's output.

Not every renderer can apply every control:

The Metal renderer, the Android GPU image renderer and the Apple Core Graphics renderers apply all five.
The Android view renderer and the Compose video draw apply the matrix through the platform's own colour filter. That filter has no power curve, so they ignore gamma.
The desktop AWT renderer, the web canvas renderer and the sample-buffer renderer apply none.

Constructors

VideoAdjustments

constructor(brightness: Float = 0.0f, contrast: Float = 1.0f, saturation: Float = 1.0f, hueDegrees: Float = 0.0f, gamma: Float = 1.0f)

Types

Companion

object Companion

Properties

brightness

val brightness: Float

Additive lift, -1 to 1. 0 is neutral; positive lightens.

contrast

val contrast: Float

Scale about mid-grey, 0 to 2. 1 is neutral; 0 is flat grey.

gamma

val gamma: Float

Power curve on each channel, 0.5 to 2. 1 is neutral; above 1 lifts the mid tones.

hueDegrees

val hueDegrees: Float

Rotation about the luma axis in degrees, -180 to 180. 0 is neutral.

isIdentity

val isIdentity: Boolean

True for the neutral value, which renderers use to skip every step entirely.

saturation

val saturation: Float

Colourfulness, 0 to 2. 1 is neutral; 0 is greyscale by the BT.709 weights.

Functions

toColorMatrix

fun toColorMatrix(): FloatArray

Brightness, contrast, saturation and hue as one 4x5 row-major colour matrix over non-premultiplied RGBA in the UNIT domain: r' = m[0]r + m[1]g + m[2]b + m[3]a + m[4], rows r, g, b, a. Offsets are in 0..1; a consumer whose convention offsets in 0..255 (Android's ColorMatrix, Compose's) multiplies the fifth column by 255 and changes nothing else.