Transformer.Builder

public Builder(Context context)

Creates a builder with default values.

@CanIgnoreReturnValue
public Transformer.Builder addListener(Transformer.Listener listener)

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

This is equivalent to addListener.

public Transformer build()

Builds a Transformer instance.

@CanIgnoreReturnValue
public Transformer.Builder experimentalSetMaxFramesInEncoder(int maxFramesInEncoder)

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 INDEX_UNSET, which means no limit is enforced.

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

@CanIgnoreReturnValue
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.

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 optimizationResult will indicate whether the optimization was applied.

@CanIgnoreReturnValue
public Transformer.Builder removeAllListeners()

Removes all listeners.

This is equivalent to removeAllListeners.

@CanIgnoreReturnValue
public Transformer.Builder removeListener(Transformer.Listener listener)

Removes a Transformer.Listener.

This is equivalent to removeListener.

@CanIgnoreReturnValue
public Transformer.Builder setAssetLoaderFactory(AssetLoader.Factory assetLoaderFactory)

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

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

@CanIgnoreReturnValue
public Transformer.Builder setAudioMimeType(String audioMimeType)

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:

• AUDIO_AAC
• AUDIO_AMR_NB
• AUDIO_AMR_WB

@CanIgnoreReturnValue
public Transformer.Builder setAudioMixerFactory(AudioMixer.Factory audioMixerFactory)

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

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

@CanIgnoreReturnValue
public Transformer.Builder setDebugViewProvider(DebugViewProvider debugViewProvider)

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

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

Not all exports will result in debug views being populated.

@CanIgnoreReturnValue
public Transformer.Builder setEncoderFactory(Codec.EncoderFactory encoderFactory)

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

The default value is a DefaultEncoderFactory instance.

@CanIgnoreReturnValue
public Transformer.Builder setEnsureFileStartsOnVideoFrameEnabled(boolean enabled)

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.

@CanIgnoreReturnValue
public Transformer.Builder setLooper(Looper looper)

Sets the Looper 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.

@CanIgnoreReturnValue
public Transformer.Builder setMaxDelayBetweenMuxerSamplesMs(long maxDelayBetweenMuxerSamplesMs)

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

@CanIgnoreReturnValue
public Transformer.Builder setMuxerFactory(Muxer.Factory muxerFactory)

Sets the Muxer.Factory for muxers that write the media container.

The default value is a DefaultMuxer.Factory.

@CanIgnoreReturnValue
public Transformer.Builder setPortraitEncodingEnabled(boolean enabled)

Sets whether to encode portrait videos in portrait orientation.

The default value is false. In this case, portrait videos will be rotated by 90 degrees before being encoded, and metadata will be added to the output file to indicate that the video should be rotated back when played. This is done because encoding landscape videos is more largely supported. Enabling portrait encoding should therefore be done carefully because it is likely to result in more failures.

@CanIgnoreReturnValue
public Transformer.Builder setVideoFrameProcessorFactory(
    VideoFrameProcessor.Factory videoFrameProcessorFactory
)

Sets the VideoFrameProcessor.Factory to be used to create VideoFrameProcessor instances.

The default value is a DefaultVideoFrameProcessor.Factory built with default values.

If passing in a DefaultVideoFrameProcessor.Factory, the caller must not set the texture output.

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

@CanIgnoreReturnValue
public Transformer.Builder setVideoMimeType(String videoMimeType)

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:

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