@UnstableApi
abstract class SimpleDecoder<I : DecoderInputBuffer?, O : DecoderOutputBuffer?, E : DecoderException?> : Decoder

Known direct subclasses
BitmapFactoryImageDecoder

An image decoder that uses BitmapFactory to decode images.
SimpleSubtitleDecoder

Base class for subtitle parsers that use their own decode thread.

Base class for Decoders that use their own decode thread and decode each input buffer immediately into a corresponding output buffer.

Summary

Protected constructors
SimpleDecoder(inputBuffers: Array<I!>!, outputBuffers: Array<O!>!)

Public functions
I?

Dequeues the next input buffer to be filled and queued to the decoder.
O?

Dequeues the next output buffer from the decoder.
Unit

Flushes the decoder.
Unit
queueInputBuffer(inputBuffer: I!)

Queues an input buffer to the decoder.
Unit

Releases the decoder.
Unit
setOutputStartTimeUs(outputStartTimeUs: Long)

Sets the timestamp from which output buffers should be produced, in microseconds.

Protected functions
abstract I!

Creates a new input buffer.
abstract O!

Creates a new output buffer.
abstract E!

Creates an exception to propagate for an unexpected decode error.
abstract E?
decode(inputBuffer: I!, outputBuffer: O!, reset: Boolean)

Decodes the inputBuffer and stores any decoded output in outputBuffer.
Boolean

Returns whether a sample time is greater or equal to the output start time, if set.
Unit
@CallSuper
releaseOutputBuffer(outputBuffer: O!)

Releases an output buffer back to the decoder.
Unit

Sets the initial size of each input buffer.

Inherited functions
From androidx.media3.decoder.Decoder
abstract String!

Returns the name of the decoder.

Protected constructors

SimpleDecoder

protected SimpleDecoder(inputBuffers: Array<I!>!, outputBuffers: Array<O!>!)
Parameters
inputBuffers: Array<I!>!

An array of nulls that will be used to store references to input buffers.
outputBuffers: Array<O!>!

An array of nulls that will be used to store references to output buffers.

Public functions

dequeueInputBuffer

fun dequeueInputBuffer(): I?

Dequeues the next input buffer to be filled and queued to the decoder.

Returns
I?

The input buffer, which will have been cleared, or null if a buffer isn't available.
Throws
E

If a decoder error has occurred.
androidx.media3.decoder.SimpleDecoder

dequeueOutputBuffer

fun dequeueOutputBuffer(): O?

Dequeues the next output buffer from the decoder.

Returns
O?

The output buffer, or null if an output buffer isn't available.
Throws
E

If a decoder error has occurred.
androidx.media3.decoder.SimpleDecoder

flush

fun flush(): Unit

Flushes the decoder. Ownership of dequeued input buffers is returned to the decoder. The caller is still responsible for releasing any dequeued output buffers.

queueInputBuffer

fun queueInputBuffer(inputBuffer: I!): Unit

Queues an input buffer to the decoder.

Parameters
inputBuffer: I!

The input buffer.
Throws
E

If a decoder error has occurred.
androidx.media3.decoder.SimpleDecoder

release

@CallSuper
fun release(): Unit

Releases the decoder. Must be called when the decoder is no longer needed.

setOutputStartTimeUs

fun setOutputStartTimeUs(outputStartTimeUs: Long): Unit

Sets the timestamp from which output buffers should be produced, in microseconds.

Any decoded buffer with a timestamp less than outputStartTimeUs should be skipped by the implementation and not made available via dequeueOutputBuffer.

This method must only be called before queuing the first input buffer initially or after flush.

Parameters
outputStartTimeUs: Long

The time from which output buffer should be produced, in microseconds.

Protected functions

createInputBuffer

protected abstract fun createInputBuffer(): I!

Creates a new input buffer.

createOutputBuffer

protected abstract fun createOutputBuffer(): O!

Creates a new output buffer.

createUnexpectedDecodeException

protected abstract fun createUnexpectedDecodeException(error: Throwable!): E!

Creates an exception to propagate for an unexpected decode error.

Parameters
error: Throwable!

The unexpected decode error.
Returns
E!

The exception to propagate.

decode

protected abstract fun decode(inputBuffer: I!, outputBuffer: O!, reset: Boolean): E?

Decodes the inputBuffer and stores any decoded output in outputBuffer.

Parameters
inputBuffer: I!

The buffer to decode.
outputBuffer: O!

The output buffer to store decoded data. The output buffer will not be made available to dequeue if its timeUs is not at least the output start time or when it's marked with shouldBeSkipped. The output buffer may not have been populated in these cases.
reset: Boolean

Whether the decoder must be reset before decoding.
Returns
E?

A decoder exception if an error occurred, or null if decoding was successful.

isAtLeastOutputStartTimeUs

protected fun isAtLeastOutputStartTimeUs(timeUs: Long): Boolean

Returns whether a sample time is greater or equal to the output start time, if set.

If this method returns false, the buffer will not be made available as an output buffer.

Parameters
timeUs: Long

The buffer time, in microseconds.
Returns
Boolean

Whether the buffer time is greater or equal to the output start time, or true if the output start time is not set.

releaseOutputBuffer

@CallSuper
protected fun releaseOutputBuffer(outputBuffer: O!): Unit

Releases an output buffer back to the decoder.

Parameters
outputBuffer: O!

The output buffer being released.

setInitialInputBufferSize

protected fun setInitialInputBufferSize(size: Int): Unit

Sets the initial size of each input buffer.

This method should only be called before the decoder is used (i.e. before the first call to dequeueInputBuffer.

Parameters
size: Int

The required input buffer size.