Most visited

Recently visited

Results for

Added in API level 14

SynthesisCallback

public interface SynthesisCallback

android.speech.tts.SynthesisCallback

A callback to return speech data synthesized by a text to speech engine. The engine can provide streaming audio by calling start(int, int, int), then audioAvailable(byte[], int, int) until all audio has been provided, then finally done(). error() can be called at any stage in the synthesis process to indicate that an error has occurred, but if the call is made after a call to done(), it might be discarded. done() must be called at the end of synthesis, regardless of errors. All methods can be only called on the synthesis thread.

Summary

Public methods
`abstract int`	`audioAvailable(byte[] buffer, int offset, int length)` The service should call this method when synthesized audio is ready for consumption.
`abstract int`	`done()` The service should call this method when all the synthesized audio for a request has been passed to `audioAvailable(byte[], int, int)`.
`abstract void`	`error(int errorCode)` The service should call this method if the speech synthesis fails.
`abstract void`	`error()` The service should call this method if the speech synthesis fails.
`abstract int`	`getMaxBufferSize()`
`abstract boolean`	`hasFinished()` Check if `done()` was called or not.
`abstract boolean`	`hasStarted()` Check if `start(int, int, int)` was called or not.
`abstract int`	`start(int sampleRateInHz, int audioFormat, int channelCount)` The service should call this when it starts to synthesize audio for this request.

Public methods

audioAvailable

Added in API level 14

int audioAvailable (byte[] buffer, 
                int offset, 
                int length)

The service should call this method when synthesized audio is ready for consumption. This method should only be called on the synthesis thread, while in onSynthesizeText(SynthesisRequest, SynthesisCallback).

Parameters
`buffer`	`byte`: The generated audio data. This method will not hold on to `buffer`, so the caller is free to modify it after this method returns.
`offset`	`int`: The offset into `buffer` where the audio data starts.
`length`	`int`: The number of bytes of audio data in `buffer`. This must be less than or equal to the return value of `getMaxBufferSize()`.

Returns
`int`	`SUCCESS`, `ERROR` or `STOPPED`.

done

Added in API level 14

int done ()

The service should call this method when all the synthesized audio for a request has been passed to audioAvailable(byte[], int, int). This method should only be called on the synthesis thread, while in onSynthesizeText(SynthesisRequest, SynthesisCallback). This method has to be called if start(int, int, int) and/or error() was called.

Returns
`int`	`SUCCESS`, `ERROR` or `STOPPED`.

error

Added in API level 21

void error (int errorCode)

The service should call this method if the speech synthesis fails. This method should only be called on the synthesis thread, while in onSynthesizeText(SynthesisRequest, SynthesisCallback).

Parameters
`errorCode`	`int`: Error code to pass to the client. One of the ERROR_ values from `TextToSpeech`

error

Added in API level 14

void error ()

The service should call this method if the speech synthesis fails. This method should only be called on the synthesis thread, while in onSynthesizeText(SynthesisRequest, SynthesisCallback).

getMaxBufferSize

Added in API level 14

int getMaxBufferSize ()

Returns
`int`	the maximum number of bytes that the TTS engine can pass in a single call of `audioAvailable(byte[], int, int)`. Calls to `audioAvailable(byte[], int, int)` with data lengths larger than this value will not succeed.

hasFinished

Added in API level 21

boolean hasFinished ()

Check if done() was called or not. This method should only be called on the synthesis thread, while in onSynthesizeText(SynthesisRequest, SynthesisCallback). Useful for checking if a fallback from network request is possible.

Returns
`boolean`

hasStarted

Added in API level 21

boolean hasStarted ()

Check if start(int, int, int) was called or not. This method should only be called on the synthesis thread, while in onSynthesizeText(SynthesisRequest, SynthesisCallback). Useful for checking if a fallback from network request is possible.

Returns
`boolean`

start

Added in API level 14

int start (int sampleRateInHz, 
                int audioFormat, 
                int channelCount)

The service should call this when it starts to synthesize audio for this request. This method should only be called on the synthesis thread, while in onSynthesizeText(SynthesisRequest, SynthesisCallback).

Parameters
`sampleRateInHz`	`int`: Sample rate in HZ of the generated audio.
`audioFormat`	`int`: Audio format of the generated audio. Must be one of `ENCODING_PCM_8BIT` or `ENCODING_PCM_16BIT`. Can also be `ENCODING_PCM_FLOAT` when targetting Android N and above.
`channelCount`	`int`: The number of channels. Must be `1` or `2`.

Returns
`int`	`SUCCESS`, `ERROR` or `STOPPED`.