/* * 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. */ // 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. // An example of the implementation of this interface can be found in // FIXME: add path+name to implementation of default TTS engine // Libraries implementing this interface are used in: // frameworks/base/tts/jni/android_tts_SpeechSynthesis.cpp namespace android { #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" enum tts_synth_status { TTS_SYNTH_DONE = 0, TTS_SYNTH_PENDING = 1 }; enum tts_callback_status { TTS_CALLBACK_HALT = 0, TTS_CALLBACK_CONTINUE = 1 }; // NOTE: This is duplicated in compat/jni/tts.h. Please // make changes there as well. enum tts_audio_format { TTS_AUDIO_FORMAT_INVALID = -1, TTS_AUDIO_FORMAT_DEFAULT = 0, TTS_AUDIO_FORMAT_PCM_16_BIT = 1, TTS_AUDIO_FORMAT_PCM_8_BIT = 2, }; // The callback is used by the implementation of this interface to notify its // client, the Android TTS service, that the last requested synthesis has been // completed. // TODO reword // 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] tts_audio_format - 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 tts_callback_status (synthDoneCB_t)(void *&, uint32_t, tts_audio_format, int, int8_t *&, size_t&, tts_synth_status); class TtsEngine; extern "C" TtsEngine* getTtsEngine(); enum tts_result { TTS_SUCCESS = 0, TTS_FAILURE = -1, TTS_FEATURE_UNSUPPORTED = -2, TTS_VALUE_INVALID = -3, TTS_PROPERTY_UNSUPPORTED = -4, TTS_PROPERTY_SIZE_TOO_SMALL = -5, TTS_MISSING_RESOURCES = -6 }; enum tts_support_result { TTS_LANG_COUNTRY_VAR_AVAILABLE = 2, TTS_LANG_COUNTRY_AVAILABLE = 1, TTS_LANG_AVAILABLE = 0, TTS_LANG_MISSING_DATA = -1, TTS_LANG_NOT_SUPPORTED = -2 }; class TtsEngine { public: virtual ~TtsEngine() {} // Initialize the TTS engine and returns whether initialization succeeded. // @param synthDoneCBPtr synthesis callback function pointer // @return TTS_SUCCESS, or TTS_FAILURE virtual tts_result init(synthDoneCB_t synthDoneCBPtr, const char *engineConfig); // Shut down the TTS engine and releases all associated resources. // @return TTS_SUCCESS, or TTS_FAILURE virtual tts_result shutdown(); // 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 virtual tts_result stop(); // 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. virtual tts_support_result isLanguageAvailable(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 virtual tts_result loadLanguage(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 virtual tts_result setLanguage(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 virtual tts_result getLanguage(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 virtual tts_result setAudioFormat(tts_audio_format& encoding, uint32_t& rate, int& channels); // 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 virtual tts_result setProperty(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 virtual tts_result getProperty(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 virtual tts_result synthesizeText(const char *text, int8_t *buffer, size_t bufferSize, void *userdata); }; } // namespace android