@UnstableApi
abstract class BaseRenderer : Renderer, RendererCapabilities

Known direct subclasses
CameraMotionRenderer

A Renderer that parses the camera motion track.

DecoderAudioRenderer

Decodes and renders audio using a Decoder.

DecoderVideoRenderer

Decodes and renders video using a Decoder.

FakeRenderer

Fake Renderer that supports any format with the matching track type.

ImageRenderer

A Renderer implementation for images.

MediaCodecRenderer

An abstract renderer that uses MediaCodec to decode samples for rendering.

MetadataRenderer

A renderer for metadata.

TextRenderer

A Renderer for text.


An abstract base class suitable for most Renderer implementations.

It converts many of the state transitions explained in Renderer docs to protected callbacks and provides utilities to access current state values without tracking them manually:

Summary

Public constructors

Public functions

Unit

Clears the Listener.

Unit

Disable the renderer, transitioning it to the STATE_DISABLED state.

Unit
enable(
    configuration: RendererConfiguration!,
    formats: Array<Format!>!,
    stream: SampleStream!,
    positionUs: Long,
    joining: Boolean,
    mayRenderStartOfStream: Boolean,
    startPositionUs: Long,
    offsetUs: Long,
    mediaPeriodId: MediaSource.MediaPeriodId!
)

Enables the renderer to consume from the specified SampleStream.

RendererCapabilities!

Returns the capabilities of the renderer.

MediaClock?

If the renderer advances its own playback position then this method returns a corresponding MediaClock.

Unit
handleMessage(@Renderer.MessageType messageType: Int, message: Any?)

Handles a message delivered to the target.

Boolean

Returns whether the renderer has read the current SampleStream to the end.

Unit
init(index: Int, playerId: PlayerId!, clock: Clock!)

Initializes the renderer for playback with a player.

Boolean

Returns whether the current SampleStream will be the final one supplied before the renderer is next disabled or reset.

Unit

Throws an error that's preventing the renderer from reading from its SampleStream.

Unit

Releases the renderer.

Unit
replaceStream(
    formats: Array<Format!>!,
    stream: SampleStream!,
    startPositionUs: Long,
    offsetUs: Long,
    mediaPeriodId: MediaSource.MediaPeriodId!
)

Replaces the SampleStream from which samples will be consumed.

Unit

Forces the renderer to give up any resources (e.g. media decoders) that it may be holding.

Unit
resetPosition(positionUs: Long)

Signals to the renderer that a position discontinuity has occurred.

Unit

Signals to the renderer that the current SampleStream will be the final one supplied before it is next disabled or reset.

Unit

Sets the Listener.

Unit

Starts the renderer, meaning that calls to render will cause media to be rendered.

Unit

Stops the renderer, transitioning it to the STATE_ENABLED state.

Int

Returns the extent to which the Renderer supports adapting between supported formats that have different MIME types.

Protected functions

ExoPlaybackException!
createRendererException(
    cause: Throwable!,
    format: Format?,
    @PlaybackException.ErrorCode errorCode: Int
)

Creates an ExoPlaybackException of type TYPE_RENDERER for this renderer.

ExoPlaybackException!
createRendererException(
    cause: Throwable!,
    format: Format?,
    isRecoverable: Boolean,
    @PlaybackException.ErrorCode errorCode: Int
)

Creates an ExoPlaybackException of type TYPE_RENDERER for this renderer.

Boolean

Returns whether the upstream source is ready.

Unit

Called when the renderer is disabled.

Unit
onEnabled(joining: Boolean, mayRenderStartOfStream: Boolean)

Called when the renderer is enabled.

Unit

Called when the renderer is initialized.

Unit
onPositionReset(positionUs: Long, joining: Boolean)

Called when the position is reset.

Unit

Called when the renderer is released.

Unit

Called when the renderer capabilities are changed.

Unit

Called when the renderer is reset.

Unit

Called when the renderer is started.

Unit

Called when the renderer is stopped.

Unit
onStreamChanged(
    formats: Array<Format!>!,
    startPositionUs: Long,
    offsetUs: Long,
    mediaPeriodId: MediaSource.MediaPeriodId!
)

Called when the renderer's stream has changed.

Unit

Called when a new timeline is set.

Int
@SampleStream.ReadDataResult
readSource(
    formatHolder: FormatHolder!,
    buffer: DecoderInputBuffer!,
    @SampleStream.ReadFlags readFlags: Int
)

Reads from the enabled upstream source.

Int
skipSource(positionUs: Long)

Attempts to skip to the keyframe before the specified position, or to the end of the stream if positionUs is beyond it.

Inherited Constants

From androidx.media3.exoplayer.Renderer
const Long

Default minimum duration that the playback clock must advance before render can make progress.

const Int

Applications or extensions may define custom MSG_* constants that can be passed to renderers.

const Int

A type of a message that can be passed to an audio renderer via createMessage.

const Int

The type of a message that can be passed to audio and video renderers via createMessage.

const Int

A type of a message that can be passed to an audio renderer via createMessage.

const Int

The type of a message that can be passed to a camera motion renderer via createMessage.

const Int

The type of a message that can be passed to a video renderer via createMessage.

const Int

The type of message that can be passed to an image renderer to set a desired image output.

const Int

The type of a message that can be passed to audio renderers via createMessage.

const Int

The type of message that can be passed to a renderer to set its priority.

const Int

The type of a message that can be passed to a MediaCodec-based video renderer via createMessage.

const Int

The type of a message that can be passed to an audio renderer via createMessage.

const Int

The type of a message that can be passed to a video renderer.

const Int

The type of a message that can be passed to a video renderer via createMessage.

const Int

The type of a message that can be passed to a video renderer via createMessage.

const Int

The type of a message that can be passed to a video renderer to set the desired output resolution.

const Int

A type of a message that can be passed to an audio renderer via createMessage.

const Int

The type of a message that can be passed to a Renderer via createMessage, to inform the renderer that it can schedule waking up another component.

const Int

The renderer is disabled.

const Int

The renderer is enabled but not started.

const Int

The renderer is started.

From androidx.media3.exoplayer.RendererCapabilities
const Int

The Renderer can adapt between formats, but may suffer a brief discontinuity (~50-100ms) when adaptation occurs.

const Int

The Renderer does not support adaptation between formats.

const Int

The Renderer can seamlessly adapt between formats.

const Int

A mask to apply to Capabilities to obtain the AdaptiveSupport only.

const Int

The renderer supports audio offload and gapless transitions with this format.

const Int

Audio offload is not supported with this format.

const Int

The renderer supports audio offload and speed changes with this format.

const Int

The renderer supports audio offload with this format.

const Int

A mask to apply to Capabilities to obtain AudioOffloadSupport only.

const Int

The format exceeds the primary decoder's capabilities but is supported by fallback decoder

const Int

The format's MIME type is unsupported and the renderer may use a decoder for a fallback MIME type.

const Int

A mask to apply to Capabilities to obtain DecoderSupport only.

const Int

The renderer is able to use the primary decoder for the format's MIME type.

const Int

A mask to apply to Capabilities to obtain the C.FormatSupport only.

const Int

The renderer is not able to use hardware acceleration.

const Int

The renderer is able to use hardware acceleration.

const Int

A mask to apply to Capabilities to obtain HardwareAccelerationSupport only.

const Int

The Renderer does not support tunneled output.

const Int

The Renderer supports tunneled output.

const Int

A mask to apply to Capabilities to obtain TunnelingSupport only.

Inherited functions

From androidx.media3.exoplayer.Renderer
Unit

Enables this renderer to render the start of the stream even if the state is not STATE_STARTED yet.

Long
getDurationToProgressUs(positionUs: Long, elapsedRealtimeUs: Long)

Returns minimum amount of playback clock time that must pass in order for the render call to make progress.

abstract String!

Returns the name of this renderer, for logging and debugging purposes.

abstract Boolean

Whether the renderer is ready for the ExoPlayer instance to transition to STATE_ENDED.

abstract Boolean

Whether the renderer is able to immediately render media from the current position.

abstract Unit
render(positionUs: Long, elapsedRealtimeUs: Long)

Incrementally renders the SampleStream.

Unit
setPlaybackSpeed(currentPlaybackSpeed: Float, targetPlaybackSpeed: Float)

Indicates the playback speed to this renderer.

From androidx.media3.exoplayer.RendererCapabilities
java-static Int

Returns Capabilities for the given C.FormatSupport.

java-static Int

Returns Capabilities combining the given C.FormatSupport, and TunnelingSupport.

java-static Int
@RendererCapabilities.Capabilities
create(
    @C.FormatSupport formatSupport: Int,
    @RendererCapabilities.AdaptiveSupport adaptiveSupport: Int,
    @RendererCapabilities.TunnelingSupport tunnelingSupport: Int,
    @RendererCapabilities.AudioOffloadSupport audioOffloadSupport: Int
)

Returns Capabilities combining the given C.FormatSupport, , TunnelingSupport, and AudioOffloadSupport.

java-static Int
@RendererCapabilities.Capabilities
create(
    @C.FormatSupport formatSupport: Int,
    @RendererCapabilities.AdaptiveSupport adaptiveSupport: Int,
    @RendererCapabilities.TunnelingSupport tunnelingSupport: Int,
    @RendererCapabilities.HardwareAccelerationSupport hardwareAccelerationSupport: Int,
    @RendererCapabilities.DecoderSupport decoderSupport: Int
)

Returns Capabilities combining the given C.FormatSupport, , TunnelingSupport, HardwareAccelerationSupport, and .

java-static Int
@RendererCapabilities.Capabilities
create(
    @C.FormatSupport formatSupport: Int,
    @RendererCapabilities.AdaptiveSupport adaptiveSupport: Int,
    @RendererCapabilities.TunnelingSupport tunnelingSupport: Int,
    @RendererCapabilities.HardwareAccelerationSupport hardwareAccelerationSupport: Int,
    @RendererCapabilities.DecoderSupport decoderSupport: Int,
    @RendererCapabilities.AudioOffloadSupport audioOffloadSupport: Int
)

Returns Capabilities combining the given C.FormatSupport, , TunnelingSupport, HardwareAccelerationSupport, and AudioOffloadSupport.

java-static Int

Returns the AdaptiveSupport from the combined Capabilities.

java-static Int

Returns the AudioOffloadSupport from the combined Capabilities.

java-static Int

Returns the DecoderSupport from the combined Capabilities.

java-static Int

Returns the C.FormatSupport from the combined Capabilities.

java-static Int

Returns the HardwareAccelerationSupport from the combined Capabilities.

java-static Int

Returns the TunnelingSupport from the combined Capabilities.

java-static Boolean
isFormatSupported(
    @RendererCapabilities.Capabilities supportFlags: Int,
    allowExceedsCapabilities: Boolean
)

Returns whether the C.FormatSupport from the combined Capabilities indicates the format is supported.

abstract Int

Returns the extent to which the Renderer supports a given format.

Public constructors

BaseRenderer

BaseRenderer(@C.TrackType trackType: Int)
Parameters
@C.TrackType trackType: Int

The track type that the renderer handles. One of the C TRACK_TYPE_* constants.

Public functions

clearListener

fun clearListener(): Unit

Clears the Listener.

disable

fun disable(): Unit

Disable the renderer, transitioning it to the STATE_DISABLED state.

This method may be called when the renderer is in the following states: STATE_ENABLED.

enable

fun enable(
    configuration: RendererConfiguration!,
    formats: Array<Format!>!,
    stream: SampleStream!,
    positionUs: Long,
    joining: Boolean,
    mayRenderStartOfStream: Boolean,
    startPositionUs: Long,
    offsetUs: Long,
    mediaPeriodId: MediaSource.MediaPeriodId!
): Unit

Enables the renderer to consume from the specified SampleStream.

This method may be called when the renderer is in the following states: STATE_DISABLED.

Parameters
configuration: RendererConfiguration!

The renderer configuration.

formats: Array<Format!>!

The enabled formats.

stream: SampleStream!

The SampleStream from which the renderer should consume.

positionUs: Long

The player's current position.

joining: Boolean

Whether this renderer is being enabled to join an ongoing playback.

mayRenderStartOfStream: Boolean

Whether this renderer is allowed to render the start of the stream even if the state is not STATE_STARTED yet.

startPositionUs: Long

The start position of the stream in renderer time (microseconds).

offsetUs: Long

The offset to be added to timestamps of buffers read from stream before they are rendered.

mediaPeriodId: MediaSource.MediaPeriodId!

The MediaPeriodId of the MediaPeriod producing the stream.

getCapabilities

fun getCapabilities(): RendererCapabilities!

Returns the capabilities of the renderer.

Returns
RendererCapabilities!

The capabilities of the renderer.

getMediaClock

fun getMediaClock(): MediaClock?

If the renderer advances its own playback position then this method returns a corresponding MediaClock. If provided, the player will use the returned MediaClock as its source of time during playback. A player may have at most one renderer that returns a from this method.

Returns
MediaClock?

The MediaClock tracking the playback position of the renderer, or null.

handleMessage

fun handleMessage(@Renderer.MessageType messageType: Int, message: Any?): Unit

Handles a message delivered to the target.

Parameters
@Renderer.MessageType messageType: Int

The message type.

message: Any?

The message payload.

Throws
androidx.media3.exoplayer.ExoPlaybackException

If an error occurred whilst handling the message. Should only be thrown by targets that handle messages on the playback thread.

hasReadStreamToEnd

fun hasReadStreamToEnd(): Boolean

Returns whether the renderer has read the current SampleStream to the end.

This method may be called when the renderer is in the following states: STATE_ENABLED, STATE_STARTED.

init

fun init(index: Int, playerId: PlayerId!, clock: Clock!): Unit

Initializes the renderer for playback with a player.

Parameters
index: Int

The renderer index within the player.

playerId: PlayerId!

The PlayerId of the player.

clock: Clock!

The Clock.

isCurrentStreamFinal

fun isCurrentStreamFinal(): Boolean

Returns whether the current SampleStream will be the final one supplied before the renderer is next disabled or reset.

maybeThrowStreamError

fun maybeThrowStreamError(): Unit

Throws an error that's preventing the renderer from reading from its SampleStream. Does nothing if no such error exists.

This method may be called when the renderer is in the following states: STATE_ENABLED, STATE_STARTED.

Throws
java.io.IOException

An error that's preventing the renderer from making progress or buffering more data.

release

fun release(): Unit

Releases the renderer.

The renderer must not be used after calling this method.

replaceStream

fun replaceStream(
    formats: Array<Format!>!,
    stream: SampleStream!,
    startPositionUs: Long,
    offsetUs: Long,
    mediaPeriodId: MediaSource.MediaPeriodId!
): Unit

Replaces the SampleStream from which samples will be consumed.

This method may be called when the renderer is in the following states: STATE_ENABLED, STATE_STARTED.

Parameters
formats: Array<Format!>!

The enabled formats.

stream: SampleStream!

The SampleStream from which the renderer should consume.

startPositionUs: Long

The start position of the new stream in renderer time (microseconds).

offsetUs: Long

The offset to be added to timestamps of buffers read from stream before they are rendered.

mediaPeriodId: MediaSource.MediaPeriodId!

The MediaPeriodId of the MediaPeriod producing the stream.

reset

fun reset(): Unit

Forces the renderer to give up any resources (e.g. media decoders) that it may be holding. If the renderer is not holding any resources, the call is a no-op.

This method may be called when the renderer is in the following states: STATE_DISABLED.

resetPosition

fun resetPosition(positionUs: Long): Unit

Signals to the renderer that a position discontinuity has occurred.

After a position discontinuity, the renderer's SampleStream is guaranteed to provide samples starting from a key frame.

This method may be called when the renderer is in the following states: STATE_ENABLED, STATE_STARTED.

Parameters
positionUs: Long

The new playback position in microseconds.

Throws
androidx.media3.exoplayer.ExoPlaybackException

If an error occurs handling the reset.

setCurrentStreamFinal

fun setCurrentStreamFinal(): Unit

Signals to the renderer that the current SampleStream will be the final one supplied before it is next disabled or reset.

This method may be called when the renderer is in the following states: STATE_ENABLED, STATE_STARTED.

setListener

fun setListener(listener: RendererCapabilities.Listener!): Unit

Sets the Listener.

Parameters
listener: RendererCapabilities.Listener!

The listener to be set.

start

fun start(): Unit

Starts the renderer, meaning that calls to render will cause media to be rendered.

This method may be called when the renderer is in the following states: STATE_ENABLED.

stop

fun stop(): Unit

Stops the renderer, transitioning it to the STATE_ENABLED state.

This method may be called when the renderer is in the following states: STATE_STARTED.

supportsMixedMimeTypeAdaptation

@RendererCapabilities.AdaptiveSupport
fun supportsMixedMimeTypeAdaptation(): Int

Returns the extent to which the Renderer supports adapting between supported formats that have different MIME types.

Returns
Int

The AdaptiveSupport for adapting between supported formats that have different MIME types.

Protected functions

createRendererException

protected fun createRendererException(
    cause: Throwable!,
    format: Format?,
    @PlaybackException.ErrorCode errorCode: Int
): ExoPlaybackException!

Creates an ExoPlaybackException of type TYPE_RENDERER for this renderer.

Parameters
cause: Throwable!

The cause of the exception.

format: Format?

The current format used by the renderer. May be null.

@PlaybackException.ErrorCode errorCode: Int

A PlaybackException.ErrorCode to identify the cause of the playback failure.

Returns
ExoPlaybackException!

The created instance, in which isRecoverable is false.

createRendererException

protected fun createRendererException(
    cause: Throwable!,
    format: Format?,
    isRecoverable: Boolean,
    @PlaybackException.ErrorCode errorCode: Int
): ExoPlaybackException!

Creates an ExoPlaybackException of type TYPE_RENDERER for this renderer.

Parameters
cause: Throwable!

The cause of the exception.

format: Format?

The current format used by the renderer. May be null.

isRecoverable: Boolean

If the error is recoverable by disabling and re-enabling the renderer.

@PlaybackException.ErrorCode errorCode: Int

A PlaybackException.ErrorCode to identify the cause of the playback failure.

Returns
ExoPlaybackException!

The created instance.

isSourceReady

protected fun isSourceReady(): Boolean

Returns whether the upstream source is ready.

This method may be called when the renderer is in the following states: STATE_ENABLED, STATE_STARTED.

onDisabled

protected fun onDisabled(): Unit

Called when the renderer is disabled.

The default implementation is a no-op.

onEnabled

protected fun onEnabled(joining: Boolean, mayRenderStartOfStream: Boolean): Unit

Called when the renderer is enabled.

The default implementation is a no-op.

Parameters
joining: Boolean

Whether this renderer is being enabled to join an ongoing playback.

mayRenderStartOfStream: Boolean

Whether this renderer is allowed to render the start of the stream even if the state is not STATE_STARTED yet.

onInit

protected fun onInit(): Unit

Called when the renderer is initialized.

onPositionReset

protected fun onPositionReset(positionUs: Long, joining: Boolean): Unit

Called when the position is reset. This occurs when the renderer is enabled after onStreamChanged has been called, and also when a position discontinuity is encountered.

After a position reset, the renderer's SampleStream is guaranteed to provide samples starting from a key frame.

The default implementation is a no-op.

Parameters
positionUs: Long

The new playback position in microseconds.

joining: Boolean

Whether this renderer is being enabled to join an ongoing playback.

onRelease

protected fun onRelease(): Unit

Called when the renderer is released.

The default implementation is a no-op.

onRendererCapabilitiesChanged

protected fun onRendererCapabilitiesChanged(): Unit

Called when the renderer capabilities are changed.

onReset

protected fun onReset(): Unit

Called when the renderer is reset.

The default implementation is a no-op.

onStarted

protected fun onStarted(): Unit

Called when the renderer is started.

The default implementation is a no-op.

onStopped

protected fun onStopped(): Unit

Called when the renderer is stopped.

The default implementation is a no-op.

onStreamChanged

protected fun onStreamChanged(
    formats: Array<Format!>!,
    startPositionUs: Long,
    offsetUs: Long,
    mediaPeriodId: MediaSource.MediaPeriodId!
): Unit

Called when the renderer's stream has changed. This occurs when the renderer is enabled after onEnabled has been called, and also when the stream has been replaced whilst the renderer is enabled or started.

The default implementation is a no-op.

Parameters
formats: Array<Format!>!

The enabled formats.

startPositionUs: Long

The start position of the new stream in renderer time (microseconds).

offsetUs: Long

The offset that will be added to the timestamps of buffers read via readSource so that decoder input buffers have monotonically increasing timestamps.

mediaPeriodId: MediaSource.MediaPeriodId!

The MediaSource.MediaPeriodId of the MediaPeriod that produces the stream.

onTimelineChanged

protected fun onTimelineChanged(timeline: Timeline!): Unit

Called when a new timeline is set.

The default implementation is a no-op.

Parameters
timeline: Timeline!

The new timeline, which can also be obtained from getTimeline.

readSource

@SampleStream.ReadDataResult
protected fun readSource(
    formatHolder: FormatHolder!,
    buffer: DecoderInputBuffer!,
    @SampleStream.ReadFlags readFlags: Int
): Int

Reads from the enabled upstream source. If the upstream source has been read to the end then RESULT_BUFFER_READ is only returned if setCurrentStreamFinal has been called. RESULT_NOTHING_READ is returned otherwise.

This method may be called when the renderer is in the following states: STATE_ENABLED, STATE_STARTED.

Parameters
formatHolder: FormatHolder!

A FormatHolder to populate in the case of reading a format.

buffer: DecoderInputBuffer!

A DecoderInputBuffer to populate in the case of reading a sample or the end of the stream. If the end of the stream has been reached, the BUFFER_FLAG_END_OF_STREAM flag will be set on the buffer.

@SampleStream.ReadFlags readFlags: Int

Flags controlling the behavior of this read operation.

Returns
Int

The result of the read operation.

Throws
androidx.media3.decoder.DecoderInputBuffer.InsufficientCapacityException

If the buffer has insufficient capacity to hold the data of a sample being read. The buffer timestamp and flags are populated if this exception is thrown, but the read position is not advanced.

skipSource

protected fun skipSource(positionUs: Long): Int

Attempts to skip to the keyframe before the specified position, or to the end of the stream if positionUs is beyond it.

This method may be called when the renderer is in the following states: STATE_ENABLED, STATE_STARTED.

Parameters
positionUs: Long

The position in microseconds.

Returns
Int

The number of samples that were skipped.

Public properties

readingPositionUs

val readingPositionUsLong

state

val stateInt

stream

val streamSampleStream?

trackType

@C.TrackType
val trackTypeInt

Protected properties

clock

@MonotonicNonNull
protected val clock: @MonotonicNonNull Clock!

configuration

protected val configurationRendererConfiguration?

formatHolder

protected val formatHolderFormatHolder!

index

protected val indexInt

lastResetPositionUs

protected val lastResetPositionUsLong

playerId

@MonotonicNonNull
protected val playerId: @MonotonicNonNull PlayerId!

streamFormats

protected val streamFormatsArray<Format!>?

streamOffsetUs

protected val streamOffsetUsLong

timeline

protected var timelineTimeline!