CanvasOverlay

Kotlin |Java

@UnstableApi
abstract class CanvasOverlay : BitmapOverlay

kotlin.Any
↳	androidx.media3.effect.TextureOverlay
	↳	androidx.media3.effect.BitmapOverlay
		↳	androidx.media3.effect.CanvasOverlay

A TextOverlay that is backed by a Canvas.

Use this class when the size of the drawing Canvas is known, or when drawing to the entire video size is desied.

Summary

Public constructors
`CanvasOverlay(useInputFrameSize: Boolean)` Creates a new `CanvasOverlay`.

Public functions
`Unit`	`configure(videoSize: Size!)` Set up resources for the overlay given the input video’s dimensions.
`Bitmap!`	`getBitmap(presentationTimeUs: Long)` Returns the overlay bitmap displayed at the specified timestamp.
`abstract Unit`	`onDraw(canvas: Canvas!, presentationTimeUs: Long)` Perform custom drawing onto the `Canvas`.
`Unit`	`release()` Releases all resources.
`Unit`	`setCanvasSize(width: Int, height: Int)` Sets the size of the `Canvas`.

`java-static BitmapOverlay!`	`createStaticBitmapOverlay(overlayBitmap: Bitmap!)` Creates a `BitmapOverlay` that shows the `overlayBitmap` in the same position and size throughout the whole video.
`java-static BitmapOverlay!`	`createStaticBitmapOverlay( overlayBitmap: Bitmap!, overlaySettings: StaticOverlaySettings! )` Creates a `BitmapOverlay` that shows the `overlayBitmap` in the same throughout the whole video.
`java-static BitmapOverlay!`	`createStaticBitmapOverlay( context: Context!, overlayBitmapUri: Uri!, overlaySettings: StaticOverlaySettings! )` Creates a `BitmapOverlay` that shows the input at `overlayBitmapUri` with the same `StaticOverlaySettings` throughout the whole video.
`Int`	`getTextureId(presentationTimeUs: Long)` Returns the overlay texture identifier displayed at the specified timestamp.
`Size!`	`getTextureSize(presentationTimeUs: Long)` Returns the pixel width and height of the overlay texture displayed at the specified timestamp.
`FloatArray<Float>!`	`getVertexTransformation(presentationTimeUs: Long)` Returns a 4x4 OpenGL matrix, controlling how the vertices of the overlay are displayed at the specified timestamp.

OverlaySettings!

getOverlaySettings(presentationTimeUs: Long)

Returns the OverlaySettings controlling how the overlay is displayed at the specified timestamp.

CanvasOverlay(useInputFrameSize: Boolean)

Creates a new CanvasOverlay.

Parameters
`useInputFrameSize: Boolean`	Whether to create the `Canvas` to match the input frame size, if `false`, `setCanvasSize` must be set before the first invocation to `onDraw`.

fun configure(videoSize: Size!): Unit

Set up resources for the overlay given the input video’s dimensions.

This method will be called before drawing the first frame and before drawing subsequent frames with different input dimensions.

Parameters
`videoSize: Size!`	The width and height of the input video, in pixels.

fun getBitmap(presentationTimeUs: Long): Bitmap!

Returns the overlay bitmap displayed at the specified timestamp.

Parameters
`presentationTimeUs: Long`	The presentation timestamp of the current frame, in microseconds.

Throws
`androidx.media3.common.VideoFrameProcessingException`	If an error occurs while processing or drawing the frame.

abstract fun onDraw(canvas: Canvas!, presentationTimeUs: Long): Unit

Perform custom drawing onto the Canvas.

Parameters
`canvas: Canvas!`	The `Canvas` to draw onto.
`presentationTimeUs: Long`	The presentation timestamp, in microseconds.

fun release(): Unit

Releases all resources.

Throws
`androidx.media3.common.VideoFrameProcessingException`	If an error occurs while releasing resources.

fun setCanvasSize(width: Int, height: Int): Unit

Sets the size of the Canvas.

The default canvas size will be of the same size as the video frame.

The size will be applied on the next invocation of onDraw.