/*
* Copyright (C) 2009 Google Inc.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#ifndef ANDROID_TTS_H
#define ANDROID_TTS_H
// This header defines the interface used by the Android platform
// to access Text-To-Speech functionality in shared libraries that implement
// speech synthesis and the management of resources associated with the
// synthesis.
// The shared library must contain a function named "android_getTtsEngine"
// that returns an 'android_tts_engine_t' instance.
#ifdef __cplusplus
extern "C" {
#endif
#define ANDROID_TTS_ENGINE_PROPERTY_CONFIG "engineConfig"
#define ANDROID_TTS_ENGINE_PROPERTY_PITCH "pitch"
#define ANDROID_TTS_ENGINE_PROPERTY_RATE "rate"
#define ANDROID_TTS_ENGINE_PROPERTY_VOLUME "volume"
typedef enum {
ANDROID_TTS_SUCCESS = 0,
ANDROID_TTS_FAILURE = -1,
ANDROID_TTS_FEATURE_UNSUPPORTED = -2,
ANDROID_TTS_VALUE_INVALID = -3,
ANDROID_TTS_PROPERTY_UNSUPPORTED = -4,
ANDROID_TTS_PROPERTY_SIZE_TOO_SMALL = -5,
ANDROID_TTS_MISSING_RESOURCES = -6
} android_tts_result_t;
typedef enum {
ANDROID_TTS_LANG_COUNTRY_VAR_AVAILABLE = 2,
ANDROID_TTS_LANG_COUNTRY_AVAILABLE = 1,
ANDROID_TTS_LANG_AVAILABLE = 0,
ANDROID_TTS_LANG_MISSING_DATA = -1,
ANDROID_TTS_LANG_NOT_SUPPORTED = -2
} android_tts_support_result_t;
typedef enum {
ANDROID_TTS_SYNTH_DONE = 0,
ANDROID_TTS_SYNTH_PENDING = 1
} android_tts_synth_status_t;
typedef enum {
ANDROID_TTS_CALLBACK_HALT = 0,
ANDROID_TTS_CALLBACK_CONTINUE = 1
} android_tts_callback_status_t;
// Supported audio formats
//
// NOTE: This is duplicated in compat/include/TtsEngine.h
// Please make changes there as well.
typedef enum {
ANDROID_TTS_AUDIO_FORMAT_INVALID = -1,
ANDROID_TTS_AUDIO_FORMAT_DEFAULT = 0,
ANDROID_TTS_AUDIO_FORMAT_PCM_16_BIT = 1,
ANDROID_TTS_AUDIO_FORMAT_PCM_8_BIT = 2,
} android_tts_audio_format_t;
/* An android_tts_engine_t object can be anything, but must have,
* as its first field, a pointer to a table of functions.
*
* See the full definition of struct android_tts_engine_t_funcs_t
* below for details.
*/
typedef struct android_tts_engine_funcs_t android_tts_engine_funcs_t;
typedef struct {
android_tts_engine_funcs_t *funcs;
} android_tts_engine_t;
/* This function must be located in the TTS Engine shared library
* and must return the address of an android_tts_engine_t library.
*/
extern android_tts_engine_t *android_getTtsEngine();
/* Including the old version for legacy support (Froyo compatibility).
* This should return the same thing as android_getTtsEngine.
*/
extern "C" android_tts_engine_t *getTtsEngine();
// A callback type used to notify the framework of new synthetized
// audio samples, status will be SYNTH_DONE for the last sample of
// the last request, of SYNTH_PENDING otherwise.
//
// This is passed by the framework to the engine through the
// 'engine_init' function (see below).
//
// The callback for synthesis completed takes:
// @param [inout] void *& - The userdata pointer set in the original
// synth call
// @param [in] uint32_t - Track sampling rate in Hz
// @param [in] uint32_t - The audio format
// @param [in] int - The number of channels
// @param [inout] int8_t *& - A buffer of audio data only valid during the
// execution of the callback
// @param [inout] size_t & - The size of the buffer
// @param [in] tts_synth_status - indicate whether the synthesis is done, or
// if more data is to be synthesized.
// @return TTS_CALLBACK_HALT to indicate the synthesis must stop,
// TTS_CALLBACK_CONTINUE to indicate the synthesis must continue if
// there is more data to produce.
typedef android_tts_callback_status_t (*android_tts_synth_cb_t)
(void **pUserData,
uint32_t trackSamplingHz,
android_tts_audio_format_t audioFormat,
int channelCount,
int8_t **pAudioBuffer,
size_t *pBufferSize,
android_tts_synth_status_t status);
// The table of function pointers that the android_tts_engine_t must point to.
// Note that each of these functions will take a handle to the engine itself
// as their first parameter.
//
struct android_tts_engine_funcs_t {
// reserved fields, ignored by the framework
// they must be placed here to ensure binary compatibility
// of legacy binary plugins.
void *reserved[2];
// Initialize the TTS engine and returns whether initialization succeeded.
// @param synthDoneCBPtr synthesis callback function pointer
// @return TTS_SUCCESS, or TTS_FAILURE
android_tts_result_t (*init)
(void *engine,
android_tts_synth_cb_t synthDonePtr,
const char *engineConfig);
// Shut down the TTS engine and releases all associated resources.
// @return TTS_SUCCESS, or TTS_FAILURE
android_tts_result_t (*shutdown)
(void *engine);
// Interrupt synthesis and flushes any synthesized data that hasn't been
// output yet. This will block until callbacks underway are completed.
// @return TTS_SUCCESS, or TTS_FAILURE
android_tts_result_t (*stop)
(void *engine);
// Returns the level of support for the language, country and variant.
// @return TTS_LANG_COUNTRY_VAR_AVAILABLE if the language, country and variant are supported,
// and the corresponding resources are correctly installed
// TTS_LANG_COUNTRY_AVAILABLE if the language and country are supported and the
// corresponding resources are correctly installed, but there is no match for
// the specified variant
// TTS_LANG_AVAILABLE if the language is supported and the
// corresponding resources are correctly installed, but there is no match for
// the specified country and variant
// TTS_LANG_MISSING_DATA if the required resources to provide any level of support
// for the language are not correctly installed
// TTS_LANG_NOT_SUPPORTED if the language is not supported by the TTS engine.
android_tts_support_result_t (*isLanguageAvailable)
(void *engine,
const char *lang,
const char *country,
const char *variant);
// Load the resources associated with the specified language. The loaded
// language will only be used once a call to setLanguage() with the same
// language value is issued. Language and country values are coded according to the ISO three
// letter codes for languages and countries, as can be retrieved from a java.util.Locale
// instance. The variant value is encoded as the variant string retrieved from a
// java.util.Locale instance built with that variant data.
// @param lang pointer to the ISO three letter code for the language
// @param country pointer to the ISO three letter code for the country
// @param variant pointer to the variant code
// @return TTS_SUCCESS, or TTS_FAILURE
android_tts_result_t (*loadLanguage)
(void *engine,
const char *lang,
const char *country,
const char *variant);
// Load the resources associated with the specified language, country and Locale variant.
// The loaded language will only be used once a call to setLanguageFromLocale() with the same
// language value is issued. Language and country values are coded according to the ISO three
// letter codes for languages and countries, as can be retrieved from a java.util.Locale
// instance. The variant value is encoded as the variant string retrieved from a
// java.util.Locale instance built with that variant data.
// @param lang pointer to the ISO three letter code for the language
// @param country pointer to the ISO three letter code for the country
// @param variant pointer to the variant code
// @return TTS_SUCCESS, or TTS_FAILURE
android_tts_result_t (*setLanguage)
(void *engine,
const char *lang,
const char *country,
const char *variant);
// Retrieve the currently set language, country and variant, or empty strings if none of
// parameters have been set. Language and country are represented by their 3-letter ISO code
// @param[out] pointer to the retrieved 3-letter code language value
// @param[out] pointer to the retrieved 3-letter code country value
// @param[out] pointer to the retrieved variant value
// @return TTS_SUCCESS, or TTS_FAILURE
android_tts_result_t (*getLanguage)
(void *engine,
char *language,
char *country,
char *variant);
// Notifies the engine what audio parameters should be used for the synthesis.
// This is meant to be used as a hint, the engine implementation will set the output values
// to those of the synthesis format, based on a given hint.
// @param[inout] encoding in: the desired audio sample format
// out: the format used by the TTS engine
// @param[inout] rate in: the desired audio sample rate
// out: the sample rate used by the TTS engine
// @param[inout] channels in: the desired number of audio channels
// out: the number of channels used by the TTS engine
// @return TTS_SUCCESS, or TTS_FAILURE
android_tts_result_t (*setAudioFormat)
(void *engine,
android_tts_audio_format_t* pEncoding,
uint32_t* pRate,
int* pChannels);
// Set a property for the the TTS engine
// "size" is the maximum size of "value" for properties "property"
// @param property pointer to the property name
// @param value pointer to the property value
// @param size maximum size required to store this type of property
// @return TTS_PROPERTY_UNSUPPORTED, or TTS_SUCCESS, or TTS_FAILURE,
// or TTS_VALUE_INVALID
android_tts_result_t (*setProperty)
(void *engine,
const char *property,
const char *value,
const size_t size);
// Retrieve a property from the TTS engine
// @param property pointer to the property name
// @param[out] value pointer to the retrieved language value
// @param[inout] iosize in: stores the size available to store the
// property value.
// out: stores the size required to hold the language
// value if getLanguage() returned
// TTS_PROPERTY_SIZE_TOO_SMALL, unchanged otherwise
// @return TTS_PROPERTY_UNSUPPORTED, or TTS_SUCCESS,
// or TTS_PROPERTY_SIZE_TOO_SMALL
android_tts_result_t (*getProperty)
(void *engine,
const char *property,
char *value,
size_t *iosize);
// Synthesize the text.
// As the synthesis is performed, the engine invokes the callback to notify
// the TTS framework that it has filled the given buffer, and indicates how
// many bytes it wrote. The callback is called repeatedly until the engine
// has generated all the audio data corresponding to the text.
// Note about the format of the input: the text parameter may use the
// following elements
// and their respective attributes as defined in the SSML 1.0 specification:
// * lang
// * say-as:
// o interpret-as
// * phoneme
// * voice:
// o gender,
// o age,
// o variant,
// o name
// * emphasis
// * break:
// o strength,
// o time
// * prosody:
// o pitch,
// o contour,
// o range,
// o rate,
// o duration,
// o volume
// * mark
// Differences between this text format and SSML are:
// * full SSML documents are not supported
// * namespaces are not supported
// Text is coded in UTF-8.
// @param text the UTF-8 text to synthesize
// @param userdata pointer to be returned when the call is invoked
// @param buffer the location where the synthesized data must be written
// @param bufferSize the number of bytes that can be written in buffer
// @return TTS_SUCCESS or TTS_FAILURE
android_tts_result_t (*synthesizeText)
(void *engine,
const char *text,
int8_t *buffer,
size_t bufferSize,
void *userdata);
};
#ifdef __cplusplus
}
#endif
#endif /* ANDROID_TTS_H */