/*
- * Copyright (c) 2011-2014 Samsung Electronics Co., Ltd All Rights Reserved
+ * Copyright (c) 2011-2016 Samsung Electronics Co., Ltd All Rights Reserved
*
* Licensed under the Apache License, Version 2.0 (the License);
* you may not use this file except in compliance with the License.
* @since_tizen @if MOBILE 2.3 @elseif WEARABLE 2.3.1 @endif
*/
typedef enum {
- STT_ERROR_NONE = TIZEN_ERROR_NONE, /**< Successful */
- STT_ERROR_OUT_OF_MEMORY = TIZEN_ERROR_OUT_OF_MEMORY, /**< Out of Memory */
- STT_ERROR_IO_ERROR = TIZEN_ERROR_IO_ERROR, /**< I/O error */
- STT_ERROR_INVALID_PARAMETER = TIZEN_ERROR_INVALID_PARAMETER,/**< Invalid parameter */
- STT_ERROR_TIMED_OUT = TIZEN_ERROR_TIMED_OUT, /**< No answer from the daemon */
- STT_ERROR_RECORDER_BUSY = TIZEN_ERROR_RESOURCE_BUSY, /**< Device or resource busy */
- STT_ERROR_OUT_OF_NETWORK = TIZEN_ERROR_NETWORK_DOWN, /**< Network is down */
- STT_ERROR_PERMISSION_DENIED = TIZEN_ERROR_PERMISSION_DENIED,/**< Permission denied */
- STT_ERROR_NOT_SUPPORTED = TIZEN_ERROR_NOT_SUPPORTED, /**< STT NOT supported */
- STT_ERROR_INVALID_STATE = TIZEN_ERROR_STT | 0x01, /**< Invalid state */
- STT_ERROR_INVALID_LANGUAGE = TIZEN_ERROR_STT | 0x02, /**< Invalid language */
- STT_ERROR_ENGINE_NOT_FOUND = TIZEN_ERROR_STT | 0x03, /**< No available engine */
- STT_ERROR_OPERATION_FAILED = TIZEN_ERROR_STT | 0x04, /**< Operation failed */
- STT_ERROR_NOT_SUPPORTED_FEATURE = TIZEN_ERROR_STT | 0x05 /**< Not supported feature of current engine */
+ STT_ERROR_NONE = TIZEN_ERROR_NONE, /**< Successful */
+ STT_ERROR_OUT_OF_MEMORY = TIZEN_ERROR_OUT_OF_MEMORY, /**< Out of Memory */
+ STT_ERROR_IO_ERROR = TIZEN_ERROR_IO_ERROR, /**< I/O error */
+ STT_ERROR_INVALID_PARAMETER = TIZEN_ERROR_INVALID_PARAMETER,/**< Invalid parameter */
+ STT_ERROR_TIMED_OUT = TIZEN_ERROR_TIMED_OUT, /**< No answer from the STT service */
+ STT_ERROR_RECORDER_BUSY = TIZEN_ERROR_RESOURCE_BUSY, /**< Device or resource busy */
+ STT_ERROR_OUT_OF_NETWORK = TIZEN_ERROR_NETWORK_DOWN, /**< Network is down */
+ STT_ERROR_PERMISSION_DENIED = TIZEN_ERROR_PERMISSION_DENIED,/**< Permission denied */
+ STT_ERROR_NOT_SUPPORTED = TIZEN_ERROR_NOT_SUPPORTED, /**< STT NOT supported */
+ STT_ERROR_INVALID_STATE = TIZEN_ERROR_STT | 0x01, /**< Invalid state */
+ STT_ERROR_INVALID_LANGUAGE = TIZEN_ERROR_STT | 0x02, /**< Invalid language */
+ STT_ERROR_ENGINE_NOT_FOUND = TIZEN_ERROR_STT | 0x03, /**< No available engine */
+ STT_ERROR_OPERATION_FAILED = TIZEN_ERROR_STT | 0x04, /**< Operation failed */
+ STT_ERROR_NOT_SUPPORTED_FEATURE = TIZEN_ERROR_STT | 0x05, /**< Not supported feature of current engine */
+ STT_ERROR_RECORDING_TIMED_OUT = TIZEN_ERROR_STT | 0x06, /**< Recording timed out @if MOBILE (Since 3.0) @elseif WEARABLE (Since 2.3.2) @endif */
+ STT_ERROR_NO_SPEECH = TIZEN_ERROR_STT | 0x07, /**< No speech while recording @if MOBILE (Since 3.0) @elseif WEARABLE (Since 2.3.2) @endif */
+ STT_ERROR_IN_PROGRESS_TO_READY = TIZEN_ERROR_STT | 0x08, /**< Progress to ready is not finished @if MOBILE (Since 3.0) @elseif WEARABLE (Since 2.3.2) @endif */
+ STT_ERROR_IN_PROGRESS_TO_RECORDING = TIZEN_ERROR_STT | 0x09, /**< Progress to recording is not finished @if MOBILE (Since 3.0) @elseif WEARABLE (Since 2.3.2) @endif */
+ STT_ERROR_IN_PROGRESS_TO_PROCESSING = TIZEN_ERROR_STT | 0x10, /**< Progress to processing is not finished @if MOBILE (Since 3.0) @elseif WEARABLE (Since 2.3.2) @endif */
+ STT_ERROR_SERVICE_RESET = TIZEN_ERROR_STT | 0x11 /**< Service reset @if MOBILE (Since 3.0) @elseif WEARABLE (Since 2.3.2) @endif */
} stt_error_e;
/**
/**
* @brief Called when the engine is changed.
- * @since_tizen 3.0
+ * @since_tizen @if MOBILE 3.0 @elseif WEARABLE 2.3.2 @endif
+ *
+ * @remarks The language is specified as an ISO 3166 alpha-2 two letter country-code followed by ISO 639-1 for the two-letter language code. For example, "ko_KR" for Korean, "en_US" for American English.
*
* @param[in] stt The STT handle
* @param[in] engine_id Engine id
* @param[in] language The default language
- * @param[in] support_silence support silence detection
- * @param[in] need_credential necessity of credential
+ * @param[in] support_silence Whether the silence detection is supported or not
+ * @param[in] need_credential The necessity of credential
* @param[in] user_data The user data passed from the callback registration function
*
* @see stt_set_engine_changed_cb()
*/
-typedef bool (*stt_engine_changed_cb)(stt_h stt, const char* engine_id, const char* language,
+typedef void (*stt_engine_changed_cb)(stt_h stt, const char* engine_id, const char* language,
bool support_silence, bool need_credential, void* user_data);
/**
* @retval #STT_ERROR_INVALID_PARAMETER Invalid parameter
* @retval #STT_ERROR_OPERATION_FAILED Operation failure
* @retval #STT_ERROR_NOT_SUPPORTED STT NOT supported
+ * @retval #STT_ERROR_PERMISSION_DENIED Permission denied
*
* @post If this function is called, the STT state will be #STT_STATE_CREATED.
*
* @retval #STT_ERROR_INVALID_PARAMETER Invalid parameter
* @retval #STT_ERROR_OPERATION_FAILED Operation failure
* @retval #STT_ERROR_NOT_SUPPORTED STT NOT supported
+ * @retval #STT_ERROR_PERMISSION_DENIED Permission denied
*
* @see stt_create()
*/
* @retval #STT_ERROR_INVALID_STATE STT Not initialized
* @retval #STT_ERROR_OPERATION_FAILED Operation failure
* @retval #STT_ERROR_NOT_SUPPORTED STT NOT supported
+ * @retval #STT_ERROR_PERMISSION_DENIED Permission denied
*
* @pre The state should be #STT_STATE_CREATED.
* @post This function invokes stt_supported_engine_cb() repeatedly for getting engine information.
* @retval #STT_ERROR_INVALID_STATE STT Not initialized
* @retval #STT_ERROR_OPERATION_FAILED Operation failure
* @retval #STT_ERROR_NOT_SUPPORTED STT NOT supported
+ * @retval #STT_ERROR_PERMISSION_DENIED Permission denied
*
* @pre The state should be #STT_STATE_CREATED.
*
* @since_tizen @if MOBILE 2.3 @elseif WEARABLE 2.3.1 @endif
* @privlevel public
* @privilege %http://tizen.org/privilege/recorder
+ * @privilege %http://tizen.org/privilege/appmanager.launch
*
* @param[in] stt The STT handle
* @param[in] engine_id Engine id
* @retval #STT_ERROR_INVALID_STATE STT Not initialized
* @retval #STT_ERROR_OPERATION_FAILED Operation failure
* @retval #STT_ERROR_NOT_SUPPORTED STT NOT supported
+ * @retval #STT_ERROR_PERMISSION_DENIED Permission denied
*
* @pre The state should be #STT_STATE_CREATED.
*
/**
* @brief Sets the app credential.
- * @since_tizen 3.0
- * @privlevel public
- * @privilege %http://tizen.org/privilege/recorder
+ * @details Using this API, the application can set a credential.
+ * The credential is a key to verify the authorization about using the engine.
+ * If the application sets the credential, it will be able to use functions of the engine entirely.
+ * @since_tizen @if MOBILE 3.0 @elseif WEARABLE 2.3.2 @endif
+ *
+ * @remarks The necessity of the credential depends on the engine. In case of the engine which is basically embedded in Tizen, the credential is not necessary so far.
+ * However, if the user wants to apply the 3rd party's engine, the credential may be necessary. In that case, please follow the policy provided by the corresponding engine.
*
* @param[in] stt The STT handle
* @param[in] credential The app credential
* @return 0 on success, otherwise a negative error value
* @retval #STT_ERROR_NONE Success
* @retval #STT_ERROR_INVALID_PARAMETER Invalid parameter
+ * @retval #STT_ERROR_INVALID_STATE Invalid state
* @retval #STT_ERROR_NOT_SUPPORTED STT NOT supported
*
* @pre The state should be #STT_STATE_CREATED or #STT_STATE_READY.
int stt_set_credential(stt_h stt, const char* credential);
/**
- * @brief Connects the daemon asynchronously.
+ * @brief Sets the private data to stt engine.
+ * @details The private data is the setting parameter for applying keys provided by the engine.
+ * Using this API, the application can set the private data and use the corresponding key of the engine.
+ * For example, if the engine provides 'partial recognition' as a recognition type, the application can set the private data as the following. \n
+ * int ret = stt_set_private_data(stt_h, "recognition_type", "PARTIAL");
+ *
+ * @since_tizen @if MOBILE 3.0 @elseif WEARABLE 2.3.2 @endif
+ *
+ * @remarks If the engine is replaced with the other engine, the key may be ignored.
+ *
+ * @param[in] stt The STT handle
+ * @param[in] key The field name of private data
+ * @param[in] data The data for set
+ *
+ * @return 0 on success, otherwise a negative error value
+ * @retval #STT_ERROR_NONE Successful
+ * @retval #STT_ERROR_INVALID_PARAMETER Invalid parameter
+ * @retval #STT_ERROR_INVALID_STATE Invalid state
+ * @retval #STT_ERROR_NOT_SUPPORTED STT NOT supported
+ * @retval #STT_ERROR_TIMED_OUT No answer from the STT service
+ *
+ * @pre The state should be #STT_STATE_READY.
+ *
+ * @see stt_get_private_data()
+*/
+int stt_set_private_data(stt_h stt, const char* key, const char* data);
+
+/**
+ * @brief Gets the private data from stt engine.
+ * @details The private data is the information provided by the engine.
+ * Using this API, the application can get the private data which corresponds to the key from the engine.
+
+ * @since_tizen @if MOBILE 3.0 @elseif WEARABLE 2.3.2 @endif
+ *
+ * @remarks If the engine is replaced with the other engine, the key may be ignored.
+ *
+ * @param[in] stt The STT handle
+ * @param[in] key The field name of private data
+ * @param[out] data The data field of private data
+ *
+ * @remarks The @a data must be released using free() when it is no longer required.
+ *
+ * @return 0 on success, otherwise a negative error value
+ * @retval #STT_ERROR_NONE Successful
+ * @retval #STT_ERROR_INVALID_PARAMETER Invalid parameter
+ * @retval #STT_ERROR_INVALID_STATE Invalid state
+ * @retval #STT_ERROR_NOT_SUPPORTED STT NOT supported
+ * @retval #STT_ERROR_TIMED_OUT No answer from the STT service
+ *
+ * @pre The state should be #STT_STATE_READY.
+ *
+ * @see stt_set_private_data()
+*/
+int stt_get_private_data(stt_h stt, const char* key, char** data);
+
+/**
+ * @brief Connects the STT service asynchronously.
* @since_tizen @if MOBILE 2.3 @elseif WEARABLE 2.3.1 @endif
* @privlevel public
* @privilege %http://tizen.org/privilege/recorder
* @retval #STT_ERROR_INVALID_PARAMETER Invalid parameter
* @retval #STT_ERROR_INVALID_STATE Invalid state
* @retval #STT_ERROR_NOT_SUPPORTED STT NOT supported
+ * @retval #STT_ERROR_PERMISSION_DENIED Permission denied
*
* @pre The state should be #STT_STATE_CREATED.
* @post If this function is successful, the STT state will be #STT_STATE_READY. \n
int stt_prepare(stt_h stt);
/**
- * @brief Disconnects the daemon.
+ * @brief Disconnects the STT service.
* @since_tizen @if MOBILE 2.3 @elseif WEARABLE 2.3.1 @endif
* @privlevel public
* @privilege %http://tizen.org/privilege/recorder
* @retval #STT_ERROR_INVALID_PARAMETER Invalid parameter
* @retval #STT_ERROR_INVALID_STATE Invalid state
* @retval #STT_ERROR_NOT_SUPPORTED STT NOT supported
+ * @retval #STT_ERROR_PERMISSION_DENIED Permission denied
*
* @pre The state should be #STT_STATE_READY.
* @post If this function is called, the STT state will be #STT_STATE_CREATED.
* @return 0 on success, otherwise a negative error value
* @retval #STT_ERROR_NONE Successful
* @retval #STT_ERROR_INVALID_PARAMETER Invalid parameter
+ * @retval #STT_ERROR_OUT_OF_MEMORY Out of memory
* @retval #STT_ERROR_OPERATION_FAILED Operation failure
* @retval #STT_ERROR_ENGINE_NOT_FOUND No available engine
* @retval #STT_ERROR_NOT_SUPPORTED STT NOT supported
+ * @retval #STT_ERROR_PERMISSION_DENIED Permission denied
*
* @post This function invokes stt_supported_language_cb() repeatedly for getting languages.
*
* @retval #STT_ERROR_INVALID_PARAMETER Invalid parameter
* @retval #STT_ERROR_OPERATION_FAILED Operation failure
* @retval #STT_ERROR_NOT_SUPPORTED STT NOT supported
+ * @retval #STT_ERROR_PERMISSION_DENIED Permission denied
*
* @see stt_foreach_supported_languages()
*/
* @retval #STT_ERROR_NONE Successful
* @retval #STT_ERROR_INVALID_PARAMETER Invalid parameter
* @retval #STT_ERROR_NOT_SUPPORTED STT NOT supported
+ * @retval #STT_ERROR_PERMISSION_DENIED Permission denied
*
* @see stt_start()
* @see stt_stop()
/**
* @brief Gets the current error message.
- * @since_tizen 3.0
- * @privlevel public
- * @privilege %http://tizen.org/privilege/recorder
+ * @since_tizen @if MOBILE 3.0 @elseif WEARABLE 2.3.2 @endif
* @remarks This function should be called during an stt error callback. If not, the error as operation failure will be returned. \n
- * If the function succeeds, @a err_msg must be released using free() when it is no longer required.
+ * If the function succeeds, @a err_msg must be released using free() when it is no longer required.
*
* @param[in] stt The STT handle
* @param[out] err_msg The current error message
* @retval #STT_ERROR_OPERATION_FAILED Operation failure
* @retval #STT_ERROR_INVALID_STATE Invalid state
* @retval #STT_ERROR_NOT_SUPPORTED STT NOT supported
+ * @retval #STT_ERROR_PERMISSION_DENIED Permission denied
*
* @pre The state should be #STT_STATE_READY.
*/
* @retval #STT_ERROR_INVALID_STATE Invalid state
* @retval #STT_ERROR_NOT_SUPPORTED_FEATURE Not supported feature of current engine
* @retval #STT_ERROR_NOT_SUPPORTED STT NOT supported
+ * @retval #STT_ERROR_PERMISSION_DENIED Permission denied
*
* @pre The state should be #STT_STATE_READY.
*/
* @retval #STT_ERROR_INVALID_STATE Invalid state
* @retval #STT_ERROR_OPERATION_FAILED Operation failure
* @retval #STT_ERROR_NOT_SUPPORTED STT NOT supported
+ * @retval #STT_ERROR_PERMISSION_DENIED Permission denied
*
* @pre The state should be #STT_STATE_READY.
*/
* @retval #STT_ERROR_INVALID_STATE Invalid state
* @retval #STT_ERROR_OPERATION_FAILED Operation failure
* @retval #STT_ERROR_NOT_SUPPORTED STT NOT supported
+ * @retval #STT_ERROR_PERMISSION_DENIED Permission denied
*
* @pre The state should be #STT_STATE_READY.
*/
* @retval #STT_ERROR_INVALID_STATE Invalid state
* @retval #STT_ERROR_OPERATION_FAILED Operation failure
* @retval #STT_ERROR_NOT_SUPPORTED STT NOT supported
+ * @retval #STT_ERROR_PERMISSION_DENIED Permission denied
*
* @pre The state should be #STT_STATE_READY.
*/
* @retval #STT_ERROR_INVALID_STATE Invalid state
* @retval #STT_ERROR_OPERATION_FAILED Operation failure
* @retval #STT_ERROR_NOT_SUPPORTED STT NOT supported
+ * @retval #STT_ERROR_PERMISSION_DENIED Permission denied
*
* @pre The state should be #STT_STATE_READY.
*/
* @privlevel public
* @privilege %http://tizen.org/privilege/recorder
*
- * @remarks This function starts recording in the daemon and sending recording data to engine. \n
+ * @remarks This function starts recording in the STT service and sending recording data to engine. \n
* This work continues until stt_stop(), stt_cancel() or silence detected by engine.
*
* @param[in] stt The STT handle
* @retval #STT_ERROR_RECORDER_BUSY Recorder busy
* @retval #STT_ERROR_INVALID_LANGUAGE Invalid language
* @retval #STT_ERROR_NOT_SUPPORTED STT NOT supported
+ * @retval #STT_ERROR_PERMISSION_DENIED Permission denied
+ * @retval #STT_ERROR_IN_PROGRESS_TO_RECORDING Progress to recording is not finished
*
* @pre The state should be #STT_STATE_READY.
* @post It will invoke stt_state_changed_cb(), if you register a callback with stt_state_changed_cb(). \n
* If this function succeeds, the STT state will be #STT_STATE_RECORDING.
+ * If you call this function again before state changes, you will receive STT_ERROR_IN_PROGRESS_TO_RECORDING.
*
* @see stt_stop()
* @see stt_cancel()
* @retval #STT_ERROR_INVALID_STATE Invalid state
* @retval #STT_ERROR_OPERATION_FAILED Operation failure
* @retval #STT_ERROR_NOT_SUPPORTED STT NOT supported
+ * @retval #STT_ERROR_PERMISSION_DENIED Permission denied
+ * @retval #STT_ERROR_IN_PROGRESS_TO_READY Progress to ready is not finished
+ * @retval #STT_ERROR_IN_PROGRESS_TO_RECORDING Progress to recording is not finished
+ * @retval #STT_ERROR_IN_PROGRESS_TO_PROCESSING Progress to processing is not finished
*
* @pre The state should be #STT_STATE_RECORDING.
* @post It will invoke stt_state_changed_cb(), if you register a callback with stt_state_changed_cb(). \n
* If this function succeeds, the STT state will be #STT_STATE_PROCESSING. \n
+ * If you call this function again before state changes, you will receive STT_ERROR_IN_PROGRESS_TO_PROCESSING.
* After processing of engine, stt_result_cb() is called.
*
* @see stt_start()
* @retval #STT_ERROR_INVALID_STATE Invalid state
* @retval #STT_ERROR_OPERATION_FAILED Operation failure
* @retval #STT_ERROR_NOT_SUPPORTED STT NOT supported
+ * @retval #STT_ERROR_PERMISSION_DENIED Permission denied
+ * @retval #STT_ERROR_IN_PROGRESS_TO_READY Progress to ready is not finished
+ * @retval #STT_ERROR_IN_PROGRESS_TO_RECORDING Progress to recording is not finished
+ * @retval #STT_ERROR_IN_PROGRESS_TO_PROCESSING Progress to processing is not finished
*
* @pre The state should be #STT_STATE_RECORDING or #STT_STATE_PROCESSING.
* @post It will invoke stt_state_changed_cb(), if you register a callback with stt_state_changed_cb(). \n
* If this function succeeds, the STT state will be #STT_STATE_READY.
+ * If you call this function again before state changes, you will receive STT_ERROR_IN_PROGRESS_TO_READY.
*
* @see stt_start()
* @see stt_stop()
* @retval #STT_ERROR_INVALID_STATE Invalid state
* @retval #STT_ERROR_OPERATION_FAILED Operation failure
* @retval #STT_ERROR_NOT_SUPPORTED STT NOT supported
+ * @retval #STT_ERROR_PERMISSION_DENIED Permission denied
*
* @pre The state should be #STT_STATE_RECORDING.
*
* @retval #STT_ERROR_INVALID_PARAMETER Invalid parameter
* @retval #STT_ERROR_OPERATION_FAILED Operation failure
* @retval #STT_ERROR_NOT_SUPPORTED STT NOT supported
+ * @retval #STT_ERROR_PERMISSION_DENIED Permission denied
*
* @pre This function should be called in stt_recognition_result_cb().
* @post This function invokes stt_result_time_cb() repeatedly for getting time information.
* @retval #STT_ERROR_INVALID_PARAMETER Invalid parameter
* @retval #STT_ERROR_INVALID_STATE Invalid state
* @retval #STT_ERROR_NOT_SUPPORTED STT NOT supported
+ * @retval #STT_ERROR_PERMISSION_DENIED Permission denied
*
* @pre The state should be #STT_STATE_CREATED.
*
* @retval #STT_ERROR_INVALID_PARAMETER Invalid parameter
* @retval #STT_ERROR_INVALID_STATE Invalid state
* @retval #STT_ERROR_NOT_SUPPORTED STT NOT supported
+ * @retval #STT_ERROR_PERMISSION_DENIED Permission denied
*
* @pre The state should be #STT_STATE_CREATED.
*
* @retval #STT_ERROR_INVALID_PARAMETER Invalid parameter
* @retval #STT_ERROR_INVALID_STATE Invalid state
* @retval #STT_ERROR_NOT_SUPPORTED STT NOT supported
+ * @retval #STT_ERROR_PERMISSION_DENIED Permission denied
*
* @pre The state should be #STT_STATE_CREATED.
*
* @retval #STT_ERROR_INVALID_PARAMETER Invalid parameter
* @retval #STT_ERROR_INVALID_STATE Invalid state
* @retval #STT_ERROR_NOT_SUPPORTED STT NOT supported
+ * @retval #STT_ERROR_PERMISSION_DENIED Permission denied
*
* @pre The state should be #STT_STATE_CREATED.
*
* @retval #STT_ERROR_INVALID_PARAMETER Invalid parameter
* @retval #STT_ERROR_INVALID_STATE Invalid state
* @retval #STT_ERROR_NOT_SUPPORTED STT NOT supported
+ * @retval #STT_ERROR_PERMISSION_DENIED Permission denied
*
* @pre The state should be #STT_STATE_CREATED.
*
* @retval #STT_ERROR_INVALID_PARAMETER Invalid parameter
* @retval #STT_ERROR_INVALID_STATE Invalid state
* @retval #STT_ERROR_NOT_SUPPORTED STT NOT supported
+ * @retval #STT_ERROR_PERMISSION_DENIED Permission denied
*
* @pre The state should be #STT_STATE_CREATED.
*
* @retval #STT_ERROR_INVALID_PARAMETER Invalid parameter
* @retval #STT_ERROR_INVALID_STATE Invalid state
* @retval #STT_ERROR_NOT_SUPPORTED STT NOT supported
+ * @retval #STT_ERROR_PERMISSION_DENIED Permission denied
*
* @pre The state should be #STT_STATE_CREATED.
*
* @retval #STT_ERROR_INVALID_PARAMETER Invalid parameter
* @retval #STT_ERROR_INVALID_STATE Invalid state
* @retval #STT_ERROR_NOT_SUPPORTED STT NOT supported
+ * @retval #STT_ERROR_PERMISSION_DENIED Permission denied
*
* @pre The state should be #STT_STATE_CREATED.
*
*/
int stt_unset_default_language_changed_cb(stt_h stt);
+/**
+ * @brief Registers a callback function to detect the engine change.
+ * @since_tizen @if MOBILE 3.0 @elseif WEARABLE 2.3.2 @endif
+ *
+ * @param[in] stt The STT handle
+ * @param[in] callback The callback function to register
+ * @param[in] user_data The user data to be passed to the callback function
+ *
+ * @return 0 on success, otherwise a negative error value
+ * @retval #STT_ERROR_NONE Successful
+ * @retval #STT_ERROR_INVALID_PARAMETER Invalid parameter
+ * @retval #STT_ERROR_INVALID_STATE Invalid state
+ * @retval #STT_ERROR_NOT_SUPPORTED STT NOT supported
+ *
+ * @pre The state should be #STT_STATE_CREATED.
+ *
+ * @see stt_engine_changed_cb()
+ * @see stt_unset_engine_changed_cb()
+*/
+int stt_set_engine_changed_cb(stt_h stt, stt_engine_changed_cb callback, void* user_data);
+
+/**
+ * @brief Unregisters the callback function.
+ * @since_tizen @if MOBILE 3.0 @elseif WEARABLE 2.3.2 @endif
+ *
+ * @param[in] stt The STT handle
+ *
+ * @return 0 on success, otherwise a negative error value
+ * @retval #STT_ERROR_NONE Successful
+ * @retval #STT_ERROR_INVALID_PARAMETER Invalid parameter
+ * @retval #STT_ERROR_INVALID_STATE Invalid state
+ * @retval #STT_ERROR_NOT_SUPPORTED STT NOT supported
+ *
+ * @pre The state should be #STT_STATE_CREATED.
+ *
+ * @see stt_set_engine_changed_cb()
+*/
+int stt_unset_engine_changed_cb(stt_h stt);
+
+
#ifdef __cplusplus
}
#endif