LanczosResample

Kotlin |Java

@UnstableApi
class LanczosResample : GlEffect

A GlEffect that applies a Lanczos-windowed sinc function when resampling an image. See Filters for Common Resampling Tasks, Ken Turkowski.

The filter rescales images in both dimensions with the same scaling factor.

Summary

Public functions
`Boolean`	`isNoOp(inputWidth: Int, inputHeight: Int)` Returns whether a applies no change at every timestamp.
`java-static LanczosResample!`	`scaleToFit(width: @IntRange(from = 1) Int, height: @IntRange(from = 1) Int)` Creates an instance.
`java-static LanczosResample!`	`scaleToFitWithFlexibleOrientation( firstDimension: @IntRange(from = 1) Int, secondDimension: @IntRange(from = 1) Int )` Creates an instance.
`GlShaderProgram!`	`toGlShaderProgram(context: Context!, useHdr: Boolean)` Returns a `GlShaderProgram` that applies the effect.

Inherited functions

From androidx.media3.common.Effect

Long

getDurationAfterEffectApplied(durationUs: Long)

Returns the expected duration of the output stream when the effect is applied given a input durationUs.

Public functions

isNoOp

fun isNoOp(inputWidth: Int, inputHeight: Int): Boolean

Returns whether a applies no change at every timestamp.

This can be used as a hint to skip this instance.

For scaling factors near 1, this effect applies no change because the Lanczos algorithm won't bring a big improvement over bilinear or nearest sampling using the GPU texture units.

scaleToFit

java-static fun scaleToFit(width: @IntRange(from = 1) Int, height: @IntRange(from = 1) Int): LanczosResample!

Creates an instance.

Parameters
`width: @IntRange(from = 1) Int`	The width inside which the output contents will fit.
`height: @IntRange(from = 1) Int`	The height inside which the output contents will fit.

scaleToFitWithFlexibleOrientation

java-static fun scaleToFitWithFlexibleOrientation(
    firstDimension: @IntRange(from = 1) Int,
    secondDimension: @IntRange(from = 1) Int
): LanczosResample!

Creates an instance.

The output resolution will be either firstDimension x secondDimension or secondDimension x firstDimension. The longer of firstDimension or secondDimension will have the same orientation as the longer side of the Size passed in to configure.

Parameters
`firstDimension: @IntRange(from = 1) Int`	The first dimension of the output contents.
`secondDimension: @IntRange(from = 1) Int`	The second dimension of the output contents.

toGlShaderProgram

fun toGlShaderProgram(context: Context!, useHdr: Boolean): GlShaderProgram!

Returns a GlShaderProgram that applies the effect.

Parameters
`context: Context!`	A `Context`.
`useHdr: Boolean`	Whether input textures come from an HDR source. If `true`, colors will be in linear RGB BT.2020. If `false`, colors will be in linear RGB BT.709.

Throws
`androidx.media3.common.VideoFrameProcessingException`	If an error occurs while creating the `GlShaderProgram`.