Overview

A builder for Transformer instances.

Summary

Constructors
public	Builder(Context context) Creates a builder with default values.

Methods
public Transformer.Builder	addListener(Transformer.Listener listener) Adds a Transformer.Listener to listen to the export events.
public Transformer	build() Builds a Transformer instance.
public Transformer.Builder	experimentalSetMaxFramesInEncoder(int maxFramesInEncoder) Limits how many video frames can be processed at any time by the encoder.
public Transformer.Builder	experimentalSetTrimOptimizationEnabled(boolean enabled) Sets whether to attempt to optimize trims from the start of the EditedMediaItem by transcoding as little of the file as possible and transmuxing the rest.
public Transformer.Builder	removeAllListeners() Removes all listeners.
public Transformer.Builder	removeListener(Transformer.Listener listener) Removes a Transformer.Listener.
public Transformer.Builder	setAssetLoaderFactory(AssetLoader.Factory assetLoaderFactory) Sets the AssetLoader.Factory to be used to retrieve the samples to export.
public Transformer.Builder	setAudioMimeType(java.lang.String audioMimeType) Sets the audio MIME type of the output.
public Transformer.Builder	setAudioMixerFactory(AudioMixer.Factory audioMixerFactory) Sets the AudioMixer.Factory to be used when audio mixing is needed.
public Transformer.Builder	setAudioProcessors(java.util.List<AudioProcessor> audioProcessors)
public Transformer.Builder	setDebugViewProvider(DebugViewProvider debugViewProvider) Sets a provider for views to show diagnostic information (if available) during export.
public Transformer.Builder	setEncoderFactory(Codec.EncoderFactory encoderFactory) Sets the Codec.EncoderFactory that will be used by the transformer.
public Transformer.Builder	setEnsureFileStartsOnVideoFrameEnabled(boolean enabled) Sets whether to ensure that the output file starts on a video frame.
public Transformer.Builder	setFlattenForSlowMotion(boolean flattenForSlowMotion)
public Transformer.Builder	setListener(Transformer.Listener listener)
public Transformer.Builder	setLooper(Looper looper) Sets the that must be used for all calls to the transformer and that is used to call listeners on.
public Transformer.Builder	setMaxDelayBetweenMuxerSamplesMs(long maxDelayBetweenMuxerSamplesMs) Sets the maximum delay allowed between output samples regardless of the track type, or C.TIME_UNSET if there is no maximum.
public Transformer.Builder	setMuxerFactory(Muxer.Factory muxerFactory) Sets the androidx.media3.transformer.Muxer.Factory for muxers that write the media container.
public Transformer.Builder	setRemoveAudio(boolean removeAudio)
public Transformer.Builder	setRemoveVideo(boolean removeVideo)
public Transformer.Builder	setTransformationRequest(TransformationRequest transformationRequest)
public Transformer.Builder	setVideoEffects(java.util.List<Effect> effects)
public Transformer.Builder	setVideoFrameProcessorFactory(VideoFrameProcessor.Factory videoFrameProcessorFactory) Sets the to be used to create VideoFrameProcessor instances.
public Transformer.Builder	setVideoMimeType(java.lang.String videoMimeType) Sets the video MIME type of the output.
from java.lang.Object	clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructors

Creates a builder with default values.

Parameters:

context: The .

Methods

Sets the audio MIME type of the output.

If no audio MIME type is passed, the output audio MIME type is the same as the first MediaItem in the Composition.

Supported MIME types are:

• MimeTypes.AUDIO_AAC
• MimeTypes.AUDIO_AMR_NB
• MimeTypes.AUDIO_AMR_WB

If the MIME type is not supported, Transformer will fallback to a supported MIME type and Transformer.Listener.onFallbackApplied(Composition, TransformationRequest, TransformationRequest) will be invoked with the fallback value.

Parameters:

audioMimeType: The MIME type of the audio samples in the output.

Returns:

This builder.

Sets the video MIME type of the output.

If no video MIME type is passed, the output video MIME type is the same as the first MediaItem in the Composition.

Supported MIME types are:

• MimeTypes.VIDEO_H263
• MimeTypes.VIDEO_H264
• MimeTypes.VIDEO_H265 from API level 24
• MimeTypes.VIDEO_MP4V

If the MIME type is not supported, Transformer will fallback to a supported MIME type and Transformer.Listener.onFallbackApplied(Composition, TransformationRequest, TransformationRequest) will be invoked with the fallback value.

Parameters:

videoMimeType: The MIME type of the video samples in the output.

Returns:

This builder.

Deprecated: Use Transformer.Builder.setAudioMimeType(String), Transformer.Builder.setVideoMimeType(String) and Composition.Builder.setHdrMode(int) instead.

Deprecated: Set the audio processors in an EditedMediaItem.Builder.setEffects(Effects), and pass it to Transformer.start(EditedMediaItem, String) instead.

Deprecated: Set the video effects in an EditedMediaItem.Builder.setEffects(Effects), and pass it to Transformer.start(EditedMediaItem, String) instead.

Deprecated: Use EditedMediaItem.Builder.setRemoveAudio(boolean) to remove the audio from the EditedMediaItem passed to Transformer.start(EditedMediaItem, String) instead.

Deprecated: Use EditedMediaItem.Builder.setRemoveVideo(boolean) to remove the video from the EditedMediaItem passed to Transformer.start(EditedMediaItem, String) instead.

Deprecated: Use EditedMediaItem.Builder.setFlattenForSlowMotion(boolean) to flatten the EditedMediaItem passed to Transformer.start(EditedMediaItem, String) instead.

Sets whether to attempt to optimize trims from the start of the EditedMediaItem by transcoding as little of the file as possible and transmuxing the rest.

This optimization has the following limitations:

• Only supported for single-asset (i.e. only one EditedMediaItem in the whole Composition) exports of mp4 files.
• Not guaranteed to work with any effects.

This process relies on the given EncoderFactory providing the right encoder level and profiles when transcoding, so that the transcoded and transmuxed segments of the file can be stitched together. If the file segments can't be stitched together, Transformer throw away any progress and proceed with unoptimized export instead.

The ExportResult.optimizationResult will indicate whether the optimization was applied.

Parameters:

enabled: Whether to enable trim optimization.

Returns:

This builder.

Limits how many video frames can be processed at any time by the encoder.

A video frame starts encoding when it enters the encoder input surface, and finishes encoding when the corresponding encoder output buffer is released.

The default value is C.INDEX_UNSET, which means no limit is enforced.

This method is experimental and will be renamed or removed in a future release.

Parameters:

maxFramesInEncoder: The maximum number of frames that the video encoder is allowed to process at a time, or C.INDEX_UNSET if no limit is enforced.

Returns:

This builder.

Sets whether to ensure that the output file starts on a video frame.

Any audio samples that are earlier than the first video frame will be dropped. This can make the output of trimming operations more compatible with player implementations that don't show the first video frame until its presentation timestamp.

Ignored when trim optimization is set.

Parameters:

enabled: Whether to ensure that the file starts on a video frame.

Returns:

This builder.

Sets the maximum delay allowed between output samples regardless of the track type, or C.TIME_UNSET if there is no maximum. The default value is Transformer.DEFAULT_MAX_DELAY_BETWEEN_MUXER_SAMPLES_MS.

The export will be aborted when no sample is written in maxDelayBetweenMuxerSamplesMs. Note that there is no guarantee that the export will be aborted exactly at that time.

Parameters:

maxDelayBetweenMuxerSamplesMs: The maximum delay allowed (in microseconds).

Returns:

This builder.

Deprecated: Use Transformer.addListener(Transformer.Listener), Transformer.removeListener(Transformer.Listener) or Transformer.Builder.removeAllListeners() instead.

Adds a Transformer.Listener to listen to the export events.

This is equivalent to Transformer.addListener(Transformer.Listener).

Parameters:

listener: A Transformer.Listener.

Returns:

This builder.

Removes a Transformer.Listener.

This is equivalent to Transformer.removeListener(Transformer.Listener).

Parameters:

listener: A Transformer.Listener.

Returns:

This builder.

Removes all listeners.

This is equivalent to Transformer.removeAllListeners().

Returns:

This builder.

Sets the AssetLoader.Factory to be used to retrieve the samples to export.

The default value is a DefaultAssetLoaderFactory built with a DefaultMediaSourceFactory and a DefaultDecoderFactory.

Parameters:

assetLoaderFactory: An AssetLoader.Factory.

Returns:

This builder.

Sets the AudioMixer.Factory to be used when audio mixing is needed.

The default value is a DefaultAudioMixer.Factory with default values.

Parameters:

audioMixerFactory: A AudioMixer.Factory.

Returns:

This builder.

Sets the to be used to create VideoFrameProcessor instances.

The default value is a built with default values.

If passing in a , the caller must not .

If exporting a Composition with multiple video sequences, the must be a .

Parameters:

videoFrameProcessorFactory: A .

Returns:

This builder.

Sets the Codec.EncoderFactory that will be used by the transformer.

The default value is a DefaultEncoderFactory instance.

Parameters:

encoderFactory: The Codec.EncoderFactory instance.

Returns:

This builder.

Sets the androidx.media3.transformer.Muxer.Factory for muxers that write the media container.

The default value is a DefaultMuxer.Factory.

Parameters:

muxerFactory: A androidx.media3.transformer.Muxer.Factory.

Returns:

This builder.

Sets the that must be used for all calls to the transformer and that is used to call listeners on.

The default value is the Looper of the thread that this builder was created on, or if that thread does not have a Looper, the Looper of the application's main thread.

Parameters:

looper: A .

Returns:

This builder.

Sets a provider for views to show diagnostic information (if available) during export.

This is intended for debugging. The default value is DebugViewProvider.NONE, which doesn't show any debug info.

Not all exports will result in debug views being populated.

Parameters:

debugViewProvider: Provider for debug views.

Returns:

This builder.

Builds a Transformer instance.