/**
 * Copyright (c) 2015 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.
 * 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 __TIZEN_MEDIAVISION_FACE_H__
#define __TIZEN_MEDIAVISION_FACE_H__

#include <mv_common.h>
#include <mv_face_type.h>

#ifdef __cplusplus
extern "C" {
#endif /* __cplusplus */

/**
 * @file   mv_face.h
 * @brief  This file contains the Media Vision Face API.
 */

/**
 * @addtogroup CAPI_MEDIA_VISION_FACE_MODULE
 * @{
 */

/**
 * @brief Defines MV_FACE_DETECTION_MODEL_FILE_PATH to set face detection
 *        haarcascade xml file attribute of the engine configuration.
 * @details Face detection haarcascade model can be changed to specify the path to the file
 *
 * @since_tizen 3.0
 * @see mv_engine_config_set_string_attribute()
 * @see mv_engine_config_get_string_attribute()
 */
#define MV_FACE_DETECTION_MODEL_FILE_PATH "MV_FACE_DETECTION_MODEL_FILE_PATH"

/**
 * @brief Defines MV_FACE_RECOGNITION_MODEL_TYPE to set the method used
 *        for face recognition model learning attribute of the engine
 *        configuration.
 * @details Switches between three types of methods used for
 *          face recognition model learning. Possible values of the
 *          attribute are:
 *          1 - Eigenfaces,
 *          2 - Fisherfaces,
 *          3 - Local Binary Patterns Histograms (LBPH)
 *          Default type is LBPH
 *
 * @since_tizen 3.0
 * @see mv_engine_config_set_int_attribute()
 * @see mv_engine_config_get_int_attribute()
 */
#define MV_FACE_RECOGNITION_MODEL_TYPE "MV_FACE_RECOGNITION_MODEL_TYPE"

/**
 * @brief Define MV_FACE_DETECTION_ROI_X to set X coordinate of face detection
 *        roi (Region of Interest) as attribute of the engine configuration.
 * @details Default value is -1 (the roi will be a full image) can be changed
 *        to specify the roi for face detection
 *
 * @since_tizen 3.0
 * @see mv_engine_config_set_int_attribute()
 * @see mv_engine_config_get_int_attribute()
 */
#define MV_FACE_DETECTION_ROI_X "MV_FACE_DETECTION_ROI_X"

/**
 * @brief Define MV_FACE_DETECTION_ROI_Y to set Y coordinate of face detection
 *        roi (Region of Interest) as attribute of the engine configuration.
 * @details Default value is -1 (the roi will be a full image) can be changed
 *        to specify the roi for face detection
 *
 * @since_tizen 3.0
 * @see mv_engine_config_set_int_attribute()
 * @see mv_engine_config_get_int_attribute()
 */
#define MV_FACE_DETECTION_ROI_Y "MV_FACE_DETECTION_ROI_Y"

/**
 * @brief Define MV_FACE_DETECTION_ROI_WIDTH to set width of face detection
 *        roi (Region of Interest) as attribute of the engine configuration.
 * @details Default value is -1 (the roi will be a full image) can be changed
 *        to specify the roi for face detection
 *
 * @since_tizen 3.0
 * @see mv_engine_config_set_int_attribute()
 * @see mv_engine_config_get_int_attribute()
 */
#define MV_FACE_DETECTION_ROI_WIDTH "MV_FACE_DETECTION_ROI_WIDTH"

/**
 * @brief Define MV_FACE_DETECTION_ROI_HEIGHT to set height of face detection
 *        roi (Region of Interest) as attribute of the engine configuration.
 * @details Default value is -1 (the roi will be a full image) can be changed
 *        to specify the roi for face detection
 *
 * @since_tizen 3.0
 * @see mv_engine_config_set_int_attribute()
 * @see mv_engine_config_get_int_attribute()
 */
#define MV_FACE_DETECTION_ROI_HEIGHT "MV_FACE_DETECTION_ROI_HEIGHT"

/**
 * @brief Define MV_FACE_DETECTION_MIN_SIZE_WIDTH to set minimum width of face
 *        which will be detected as attribute of the engine configuration.
 * @details Default value is -1 (all detected faces will be applied) can be
 *        changed to specify the minimum face width
 *
 * @since_tizen 3.0
 * @see mv_engine_config_set_int_attribute()
 * @see mv_engine_config_get_int_attribute()
 */
#define MV_FACE_DETECTION_MIN_SIZE_WIDTH "MV_FACE_DETECTION_MIN_SIZE_WIDTH"

/**
 * @brief Define MV_FACE_DETECTION_MIN_SIZE_HEIGHT to set minimum height of face
 *        which will be detected as attribute of the engine configuration.
 * @details Default value is -1 (all detected faces will be applied) can be changed
 *        to specify the minimum face height
 *
 * @since_tizen 3.0
 * @see mv_engine_config_set_int_attribute()
 * @see mv_engine_config_get_int_attribute()
 */
#define MV_FACE_DETECTION_MIN_SIZE_HEIGHT "MV_FACE_DETECTION_MIN_SIZE_HEIGHT"

/******************/
/* Face detection */
/******************/

/**
 * @brief Called when faces are detected for the @a source.
 * @details This type callback can be invoked each time when
 *          @ref mv_face_detect() is called to process the results of face
 *          detecting.
 *
 * @since_tizen 3.0
 * @remarks If no face is detected then the callback will be invoked, but
 *          @a faces_locations array will be NULL, and @a number_of_faces will
 *          be equal to 0.
 * @param [in] source             The handle to the source of the media where
 *                                faces were detected
 * @param [in] engine_cfg         The handle to the configuration of engine was
 *                                used for face detecting, or NULL if default
 *                                settings were applied
 * @param [in] faces_locations    Rectangular locations of detected faces
 * @param [in] number_of_faces    Number of detected faces
 * @param [in] user_data          The user data passed from callback invoking code
 *
 * @pre Call @ref mv_face_detect() function to perform detection of the face for
 *      the face image and invoke this callback as a result
 *
 * @see mv_face_detect()
 */
typedef void (*mv_face_detected_cb)(
	mv_source_h source,
	mv_engine_config_h engine_cfg,
	mv_rectangle_s *faces_locations,
	int number_of_faces,
	void *user_data);

/**
 * @brief Performs face detection on the @a source for the @a engine_conf.
 * @details Use this function to launch face detection algorithm configured by
 *          @a engine_conf configuration. Each time when mv_face_detect is
 *          called, @a detected_cb will receive a set of the detected
 *          faces at the media source.
 *
 * @since_tizen 3.0
 * @param [in] source         The handle to the source of the media where faces
 *                            will be detected
 * @param [in] engine_cfg     The handle to the configuration of engine will be
 *                            used for detecting. If NULL, then default settings
 *                            will be used.
 * @param [in] detected_cb    The callback which will be called for all face
 *                            locations detected on media source. This callback
 *                            will receive detecting results
 * @param [in] user_data      The user data passed from the code where
 *                            @ref mv_face_detect() is invoked. This data will
 *                            be accessible from @a detected_cb callback.
 * @return @c 0 on success, otherwise a negative error value
 * @retval #MEDIA_VISION_ERROR_NONE Successful
 * @retval #MEDIA_VISION_ERROR_INVALID_PARAMETER Invalid parameter
 * @retval #MEDIA_VISION_ERROR_INVALID_OPERATION Invalid operation
 * @retval #MEDIA_VISION_ERROR_NOT_SUPPORTED_FORMAT Source colorspace
 *                                                  isn't supported
 * @retval #MEDIA_VISION_ERROR_NOT_SUPPORTED Not supported
 *
 * @pre Create a source handle by calling @ref mv_create_source()
 * @post @a detected_cb will be called to process detection results
 *
 * @see mv_face_detected_cb
 */
int mv_face_detect(
	mv_source_h source,
	mv_engine_config_h engine_cfg,
	mv_face_detected_cb detected_cb,
	void *user_data);


/********************/
/* Face recognition */
/********************/

/**
 * @brief Called each time when face is recognized by @ref mv_face_recognize()
 *        function.
 *
 * @since_tizen 3.0
 * @param [in] source              The handle to the image source for which
 *                                 face has been recognized/not recognized
 * @param [in] recognition_model   The handle to the recognition model has been
 *                                 used for recognition
 * @param [in] engine_cfg          The handle to the configuration of engine was
 *                                 used for recognition, or NULL if default
 *                                 settings were applied
 * @param [in] face_location       The pointer to the location of the face
 *                                 recognized on @a source. If face wasn't
 *                                 recognized, then pointer is NULL
 * @param [in] face_label          The label that identifies face which was
 *                                 recognized in the @a source. NULL if
 *                                 recognition was performed, but no faces
 *                                 were recognized in the @a source
 * @param [in] confidence          The confidence of the @a recognition_model
 *                                 that face has been recognized correctly
 *                                 (value from 0.0 to 1.0). No faces were
 *                                 recognized if @a confidence was 0.0.
 *                                 When model has been learned on large amount
 *                                 of examples, threshold for this value
 *                                 can be high (0.85-0.95). If model
 *                                 was learned for small amount of examples,
 *                                 then threshold can be reduced (0.5-0.85)
 * @param [in] user_data           The user data passed from callback invoking
 *                                 code
 *
 * @pre Call @ref mv_face_recognize() function to perform recognition of the
 *      face for the face image and invoke this callback as a result
 *
 * @see mv_face_recognize()
 */
typedef void (*mv_face_recognized_cb)(
	mv_source_h source,
	mv_face_recognition_model_h recognition_model,
	mv_engine_config_h engine_cfg,
	mv_rectangle_s *face_location,
	const int *face_label,
	double confidence,
	void *user_data);

/**
 * @brief Performs face recognition on the @a source image.
 * @details Use this function to launch face recognition algorithm configured by
 *          @a engine_conf configuration using @a recognition_model recognition
 *          model. Each time when @ref mv_face_recognize() is called,
 *          @a recognized_cb will receive recognition results:\n
 *          - Location in the @a source of the face has been recognized;
 *          - Label of the face has been recognized;
 *          - Confidence of the @a recognition_model that face has been
 *            recognized correctly (value from 0.0 to 1.0).
 *
 * @since_tizen 3.0
 * @remarks Using of untrained or weakly trained recognition models will cause
 *          not accurate results even if resulting confidence will be high.
 *          Use @ref mv_face_recognition_model_learn() function before
 *          @ref mv_face_recognize() call. Best results can be achieved when big
 *          set of face image examples were added by
 *          @ref mv_face_recognition_model_add() before
 *          @ref mv_face_recognition_model_learn() call.
 * @param [in] source              The handle to the source of the media to
 *                                 recognize face(s) for
 * @param [in] recognition_model   The handle to the model will be used for
 *                                 recognition
 * @param [in] engine_cfg          The handle to the configuration of engine
 *                                 will be used for recognition. If NULL, then
 *                                 default settings will be used
 * @param [in] face_location       Rectangular box bounding face image on the
 *                                 @a source. If NULL, then full source will be
 *                                 analyzed
 * @param [in] recognized_cb       The callback which will be called for the
 *                                 face recognition results on the @a source.
 * @param [in] user_data           The user data passed from the code where
 *                                 @ref mv_face_recognize() is invoked. This
 *                                 data will be accessible from @a recognized_cb
 *                                 callback
 * @return @c 0 on success, otherwise a negative error value
 * @retval #MEDIA_VISION_ERROR_NONE Successful
 * @retval #MEDIA_VISION_ERROR_INVALID_PARAMETER Invalid parameter
 * @retval #MEDIA_VISION_ERROR_INVALID_OPERATION Invalid operation
 * @retval #MEDIA_VISION_ERROR_NOT_SUPPORTED_FORMAT Source colorspace
 *                                                  isn't supported
 * @retval #MEDIA_VISION_ERROR_NOT_SUPPORTED Not supported
 *
 * @pre Create a source handle by calling @ref mv_create_source()
 * @pre Create a face recognition model handle by calling
 *      @ref mv_face_recognition_model_create()
 * @post @a recognized_cb will be called to process recognition results
 *
 * @see mv_face_recognized_cb
 */
int mv_face_recognize(
	mv_source_h source,
	mv_face_recognition_model_h recognition_model,
	mv_engine_config_h engine_cfg,
	mv_rectangle_s *face_location,
	mv_face_recognized_cb recognized_cb,
	void *user_data);


/*****************/
/* Face tracking */
/*****************/

/**
 * @brief Called when face determined by @a tracking_model is tracked.
 * @details This type callback can be invoked each time when
 *          @ref mv_face_track() is called to process the results of face
 *          tracking.
 *
 * @since_tizen 3.0
 * @param [in] source           The handle to the video frame or image from
 *                              sequence for which face was tracked
 * @param [in] tracking_model   The handle to the model that was used for
 *                              tracking
 * @param [in] engine_cfg       The handle to the configuration of engine was
 *                              used for tracking, or NULL if default settings
 *                              were applied.
 * @param [in] location         The pointer to the quadrangle-shaped location
 *                              which determines new position of the tracked
 *                              face on the @a source. If NULL, then face was
 *                              lost by tracking algorithm during last iteration
 * @param [in] confidence       The confidence of the @a tracking_model
 *                              that new location of the face was determined
 *                              correctly (value from 0.0 to 1.0).
 *                              If no location was determined during last track
 *                              iteration, then value is 0.0
 * @param [in] user_data        The user data passed from callback invoking code
 *
 * @pre Call @ref mv_face_track() function to perform track iteration for
 *      the video frame or the image from sequence and invoke this callback as
 *      a result
 *
 * @see mv_face_track()
 */
typedef void (*mv_face_tracked_cb)(
	mv_source_h source,
	mv_face_tracking_model_h tracking_model,
	mv_engine_config_h engine_cfg,
	mv_quadrangle_s *location,
	double confidence,
	void *user_data);

/**
 * @brief Performs face tracking on the @a source for the @a tracking_model.
 * @details Use this function to launch face tracking algorithm configured by
 *          @a engine_conf configuration using @a tracking_model tracking
 *          model. Each time when this function is called, @a tracked_cb
 *          will receive updated @a tracking_model, new location determined for
 *          the tracked face and model confidence that location is determined
 *          correctly.
 *
 * @since_tizen 3.0
 * @remarks To allow correct tracking @a tracking_model has to be already used
 *          in previous tracking process(es) or prepared with
 *          @ref mv_face_tracking_model_prepare(). Preparation requires
 *          specifying the face location for the @a source on which tracking was
 *          started. I.e. @ref mv_face_tracking_model_prepare() function has to
 *          be called at least once before this method call.
 * @param [in] source           The handle to the source of the media to
 *                              recognize face for
 * @param [in] tracking_model   The handle to the model will be used for
 *                              tracking
 * @param [in] engine_cfg       The handle to the configuration of engine will
 *                              be used for tracking. If NULL, the default
 *                              configuration will be used.
 * @param [in] tracked_cb       The callback which will be called for tracking
 *                              event on the @a source where face would be
 *                              tracked. This callback will receive tracking
 *                              results
 * @param [in] do_learn         The model learning flag. If it is set @c true
 *                              then model will try to learn (if it supports
 *                              learning feature), otherwise model will be not
 *                              learned during the invoking tracking iteration.
 *                              Learning process improves tracking correctness,
 *                              but can decrease tracking performance
 * @param [in] user_data        The user data passed from the code where
 *                              @ref mv_face_track() is invoked. This data will
 *                              be accessible from @a tracked_cb callback
 * @return @c 0 on success, otherwise a negative error value
 * @retval #MEDIA_VISION_ERROR_NONE Successful
 * @retval #MEDIA_VISION_ERROR_INVALID_PARAMETER Invalid parameter
 * @retval #MEDIA_VISION_ERROR_INVALID_OPERATION Invalid operation
 * @retval #MEDIA_VISION_ERROR_NOT_SUPPORTED_FORMAT Source colorspace
 *                                                  isn't supported
 * @retval #MEDIA_VISION_ERROR_NOT_SUPPORTED Not supported
 *
 * @pre Create a source handle by calling @ref mv_create_source()
 * @pre Create a face tracking model handle by calling
 *      @ref mv_face_tracking_model_create()
 * @post @a tracked_cb will be called to process tracking results
 *
 * @see mv_face_tracked_cb
 */
int mv_face_track(
	mv_source_h source,
	mv_face_tracking_model_h tracking_model,
	mv_engine_config_h engine_cfg,
	mv_face_tracked_cb tracked_cb,
	bool do_learn,
	void *user_data);


/********************************/
/* Recognition of eye condition */
/********************************/

/**
 * @brief Called when eye blink condition is recognized.
 * @details This type callback can be invoked each time when
 *          mv_face_eye_condition_recognize() is called for @a face_location to
 *          recognize eye-blink condition for the face at the @a source.\n
 *          Usage example for this callback can be found in
 *          mv_face_eye_condition_recognize() documentation.
 *
 * @since_tizen 3.0
 * @param [in] source           The handle to the source of the media for which
 *                              eye-blink condition was recognized
 * @param [in] engine_cfg       The handle to the configuration of engine was
 *                              used for eye-blink condition recognition, or
 *                              NULL if default settings were applied.
 * @param [in] face_location    The location bounding the face at the @a source
 * @param [in] eye_condition    The type of eye-blink condition recognized for
 *                              face bounded by @a face_location
 * @param [in] user_data        The user data passed from callback invoking code
 *
 *
 * @pre Call @ref mv_face_eye_condition_recognize() function to perform
 *      eye-blink condition recognition and invoke this callback as a result
 *
 * @see mv_face_eye_condition_recognize()
 */
typedef void (*mv_face_eye_condition_recognized_cb)(
	mv_source_h source,
	mv_engine_config_h engine_cfg,
	mv_rectangle_s face_location,
	mv_face_eye_condition_e eye_condition,
	void *user_data);

/**
 * @brief Determines eye-blink condition for @a face_location on media @a source.
 * @details Use this function to recognize eye-blink condition for the face
 *          bounded by @a face_location at @a source.
 *
 * @since_tizen 3.0
 * @param [in] source           The handle to the source of the media to
 *                              recognize eye-blink condition for
 * @param [in] engine_cfg       The handle to the configuration of engine
 *                              will be used for eye-blink condition
 *                              recognition. If NULL, the default configuration
 *                              will be used.
 * @param [in] face_location    The location bounding the face at the @a source
 * @param [in] eye_condition_recognized_cb    The callback for processing result
 *                              of eye-blink condition recognition
 * @param [in] user_data        The user data passed from the code where
 *                              mv_face_eye_condition_recognize() is invoked.
 *                              This data will be accessible from
 *                              @a eye_condition_recognized_cb callback.
 * @return @c 0 on success, otherwise a negative error value
 * @retval #MEDIA_VISION_ERROR_NONE Successful
 * @retval #MEDIA_VISION_ERROR_INVALID_PARAMETER Invalid parameter
 * @retval #MEDIA_VISION_ERROR_NOT_SUPPORTED_FORMAT Source colorspace
 *                                                  isn't supported
 * @retval #MEDIA_VISION_ERROR_NOT_SUPPORTED Not supported
 *
 * @pre Create a source handle by calling mv_create_source()
 *
 * @see mv_face_eye_condition_recognized_cb
 */
int mv_face_eye_condition_recognize(
	mv_source_h source,
	mv_engine_config_h engine_cfg,
	mv_rectangle_s face_location,
	mv_face_eye_condition_recognized_cb eye_condition_recognized_cb,
	void *user_data);


/************************************/
/* Recognition of facial expression */
/************************************/

/**
 * @brief Called when facial expression is recognized
 * @details This type callback can be invoked each time when
 *          mv_face_facial_expression_recognize() is called for @a face_location to
 *          recognize facial expression for the face at the @a source.\n
 *          Usage example for this callback can be found in
 *          mv_face_facial_expression_recognize() documentation.
 *
 * @since_tizen 3.0
 * @param [in] source               The handle to the source of the media for
 *                                  which facial expression was recognized
 * @param [in] engine_cfg           The handle to the configuration of engine was
 *                                  used for expression recognition
 * @param [in] face_location        The location bounding the face at the @a source
 * @param [in] facial_expression    The type of facial expression recognized
 *                                  for face bounded by @a face_location
 * @param [in] user_data            The user data passed from callback invoking code
 *
 * @pre Create a source handle by calling mv_create_source()
 * @pre Create a face engine configuration handle by calling mv_create_engine_config()
 *
 * @see mv_face_facial_expression_recognize()
 */
typedef void (*mv_face_facial_expression_recognized_cb)(
	mv_source_h source,
	mv_engine_config_h engine_cfg,
	mv_rectangle_s face_location,
	mv_face_facial_expression_e facial_expression,
	void *user_data);

/**
 * @brief Determines facial expression for @a face_location on media @a source.
 * @details Use this function to determine facial expression for the face
 *          bounded by @a face_location at @a source.
 *
 * @since_tizen 3.0
 * @param [in] source           The handle to the source of the media
 *                              to recognize facial expression for
 * @param [in] engine_cfg       The handle to the configuration of
 *                              engine will be used for expression recognition
 * @param [in] face_location    The location bounding the face at the @a source
 * @param [in] expression_recognized_cb   The callback for processing result
 *                              of facial expression determining
 * @param [in] user_data        The user data passed from the code where
 *                              mv_face_facial_expression_recognize() is invoked.
 *                              This data will be accessible from
 *                              @a expression_recognized_cb callback.
 * @return @c 0 on success, otherwise a negative error value
 * @retval #MEDIA_VISION_ERROR_NONE Successful
 * @retval #MEDIA_VISION_ERROR_INVALID_PARAMETER Invalid parameter
 * @retval #MEDIA_VISION_ERROR_NOT_SUPPORTED_FORMAT Source colorspace
 *                                                  isn't supported
 * @retval #MEDIA_VISION_ERROR_NOT_SUPPORTED Not supported
 *
 * @pre Create a source handle by calling mv_create_source()
 * @pre Create a face engine configuration handle by calling @ref mv_create_engine_config()
 *
 * @see mv_face_facial_expression_recognized_cb
 */
int mv_face_facial_expression_recognize(
	mv_source_h source,
	mv_engine_config_h engine_cfg,
	mv_rectangle_s face_location,
	mv_face_facial_expression_recognized_cb expression_recognized_cb,
	void *user_data);

/*******************************/
/* Recognition model behavior */
/*******************************/

/**
 * @brief Creates a face recognition model handle.
 * @details Use this function to create default face recognition model. Creating
 *          process is defined by concrete face engine library. After creation
 *          recognition model has to be learned with
 *          @ref mv_face_recognition_model_learn() function to provide
 *          appropriate results of face recognition functionality. Or learned
 *          earlier model can be loaded by @ref mv_face_recognition_model_load()
 *          function.
 *
 * @since_tizen 3.0
 * @remarks It can cause incompatibility issues when saved models (see
 *          @ref mv_face_recognition_model_save(),
 *          @ref mv_face_recognition_model_load()
 *          functions documentation) are used in applications for different
 *          platforms which use different computer vision libraries underlying
 *          this API.
 * @remarks You must release @a recognition_model by using
 *          @ref mv_face_recognition_model_destroy() function.
 * @param [out] recognition_model    The handle to the recognition model to be
 *                                   created
 *
 * @return @c 0 on success, otherwise a negative error value
 * @retval #MEDIA_VISION_ERROR_NONE Successful
 * @retval #MEDIA_VISION_ERROR_INVALID_PARAMETER Invalid parameter
 * @retval #MEDIA_VISION_ERROR_OUT_OF_MEMORY Out of memory
 * @retval #MEDIA_VISION_ERROR_NOT_SUPPORTED Not supported
 *
 * @post Model can be loaded from the file after creation. Use
 *       @ref mv_face_recognition_model_load() function to load it from file
 * @post Release @a recognition_model by using
 *       @ref mv_face_recognition_model_destroy() function when it is not needed
 *       anymore
 *
 * @see mv_face_recognition_model_destroy()
 */
int mv_face_recognition_model_create(
	mv_face_recognition_model_h *recognition_model);

/**
 * @brief Destroys the face recognition model handle and releases all its
 *        resources.
 *
 * @since_tizen 3.0
 * @param [in] recognition_model    The handle to the face recognition model to
 *                                  be destroyed
 * @return @c 0 on success, otherwise a negative error value
 * @retval #MEDIA_VISION_ERROR_NONE Successful
 * @retval #MEDIA_VISION_ERROR_INVALID_PARAMETER Invalid parameter
 * @retval #MEDIA_VISION_ERROR_NOT_SUPPORTED Not supported
 *
 * @pre Create recognition model by using @ref mv_face_recognition_model_create()
 *
 * @see mv_face_recognition_model_create()
 */
int mv_face_recognition_model_destroy(
	mv_face_recognition_model_h recognition_model);

/**
 * @brief Creates a copy of existed recognition model handle and clones all its
 *        resources.
 *
 * @since_tizen 3.0
 * @remarks Cloning perform not only handle copy, but also copies all internal
 *          resources of the model. @a dst must be released using
 *          @ref mv_face_recognition_model_destroy().
 * @param [in]     src    The handle to the recognition model to be copied
 * @param [out]    dst    The handle to the copy of existed recognition model
 *                        specified as @a src
 * @return @c 0 on success, otherwise a negative error value
 * @retval #MEDIA_VISION_ERROR_NONE Successful
 * @retval #MEDIA_VISION_ERROR_INVALID_PARAMETER Invalid parameter
 * @retval #MEDIA_VISION_ERROR_OUT_OF_MEMORY Out of memory
 * @retval #MEDIA_VISION_ERROR_NOT_SUPPORTED Not supported
 *
 * @pre Create face recognition handles by calling
 *      @ref mv_face_recognition_model_create()
 *
 * @see mv_face_recognition_model_create()
 */
int mv_face_recognition_model_clone(
	mv_face_recognition_model_h src,
	mv_face_recognition_model_h *dst);

/**
 * @brief Saves recognition model to the file.
 *
 * @since_tizen 3.0
 * @remarks This function doesn't save face image examples (image itself) added by
 *          @ref mv_face_recognition_model_add() function.
 *          This examples can be removed by
 *          @ref mv_face_recognition_model_reset() function if
 *          it is needed to clear the memory.
 * @remarks @a recognition_model is saved to the absolute path directory.
 *          Use @ref app_get_data_path for the private app storage path.
 *          After model is saved to the file, it can be loaded from this file
 *          by @ref mv_face_recognition_model_load() function.
 * @param [in] file_name            Name of the path/file to save the model
 * @param [in] recognition_model    The handle to the recognition model to be
 *                                  saved to the file
 * @return @c 0 on success, otherwise a negative error value
 * @retval #MEDIA_VISION_ERROR_NONE Successful
 * @retval #MEDIA_VISION_ERROR_INVALID_PARAMETER Invalid parameter
 * @retval #MEDIA_VISION_ERROR_INVALID_OPERATION Invalid operation
 * @retval #MEDIA_VISION_ERROR_INVALID_PATH Invalid path
 * @retval #MEDIA_VISION_ERROR_PERMISSION_DENIED Not permitted
 * @retval #MEDIA_VISION_ERROR_NOT_SUPPORTED_FORMAT Not supported model format
 * @retval #MEDIA_VISION_ERROR_NOT_SUPPORTED Not supported
 *
 * @pre Create a face recognition handle by calling
 *      @ref mv_face_recognition_model_create() function
 * @post Saved model can be loaded later by calling
 *      @ref mv_face_recognition_model_load() function
 *
 * @see mv_face_recognition_model_load()
 * @see mv_face_recognition_model_create()
 * @see app_get_data_path()
 */
int mv_face_recognition_model_save(
	const char *file_name,
	mv_face_recognition_model_h recognition_model);

/**
 * @brief Loads recognition model from file.
 *
 * @since_tizen 3.0
 * @remarks This function doesn't modify the set of face image examples added
 *          with @ref mv_face_recognition_model_add() function.
 *          Model will be loaded from file without loss of collected examples.
 *          If you want to free memory from examples, use
 *          @ref mv_face_recognition_model_reset() function. It
 *          is recommended to clear the memory if learning algorithm doesn't
 *          support reinforcement learning.
 * @remarks @a recognition_model is loaded from the absolute path directory.
 *          Use @ref app_get_data_path for the private app storage path.
 *          @a recognition_model must be destroyed using
 *          @ref mv_face_recognition_model_destroy().
 * @param [in]  file_name            Name of path/file to load the model
 * @param [out] recognition_model    The handle to the recognition model
 *                                   to be loaded from the file
 * @return @c 0 on success, otherwise a negative error value
 * @retval #MEDIA_VISION_ERROR_NONE Successful
 * @retval #MEDIA_VISION_ERROR_INVALID_PARAMETER Invalid parameter
 * @retval #MEDIA_VISION_ERROR_INVALID_PATH Invalid path
 * @retval #MEDIA_VISION_ERROR_PERMISSION_DENIED Not permitted
 * @retval #MEDIA_VISION_ERROR_OUT_OF_MEMORY Out of memory
 * @retval #MEDIA_VISION_ERROR_NOT_SUPPORTED_FORMAT Not supported model format
 * @retval #MEDIA_VISION_ERROR_NOT_SUPPORTED Not supported
 *
 * @pre Recognition model can be preliminary saved with
 *      @ref mv_face_recognition_model_save() function
 *
 * @see mv_face_recognition_model_save()
 * @see mv_face_recognition_model_destroy()
 * @see app_get_data_path()
 */
int mv_face_recognition_model_load(
	const char *file_name,
	mv_face_recognition_model_h *recognition_model);

/**
 * @brief Adds face image example to be used for face recognition model learning
 *        with @ref mv_face_recognition_model_learn().
 *
 * @since_tizen 3.0
 * @remarks It is possible to destroy @a source after calling this method.
 *          Source isn't used for learning directly.
 * @remarks Face image @a example_location location can be determined using
 *          @ref mv_face_detect function.
 * @param [in] source               The handle to @a source that contains face
 *                                  image
 * @param [in] recognition_model    The handle to the recognition model which
 *                                  could be learned based on example
 * @param [in] example_location     The pointer to the rectangular location of
 *                                  the face image at the source image. If NULL,
 *                                  then full image will be analyzed as the face
 *                                  image
 * @param [in] face_label           The label that identifies face for which
 *                                  example is adding. Specify the same labels
 *                                  for the face images of a single person when
 *                                  calling this method. Has to be unique for
 *                                  each face
 * @return @c 0 on success, otherwise a negative error value
 * @retval #MEDIA_VISION_ERROR_NONE Successful
 * @retval #MEDIA_VISION_ERROR_INVALID_PARAMETER Invalid parameter
 * @retval #MEDIA_VISION_ERROR_NOT_SUPPORTED_FORMAT Source colorspace
 *                                                  isn't supported
 * @retval #MEDIA_VISION_ERROR_NOT_SUPPORTED Not supported
 *
 * @pre Create a face recognition handle by calling
 *      @ref mv_face_recognition_model_create() function
 * @post When appropriate amount of face image examples is added to the
 *       @a recognition_model, this model has to be learned by
 *       @ref mv_face_recognition_model_learn() function call. Only after
 *       learning of the model it can be used for face recognition with
 *       @ref mv_face_recognize() function
 *
 * @see mv_face_recognition_model_reset()
 * @see mv_face_recognition_model_learn()
 */
int mv_face_recognition_model_add(
	const mv_source_h source,
	mv_face_recognition_model_h recognition_model,
	const mv_rectangle_s *example_location,
	int face_label);

/**
 * @brief Removes from @a recognition_model all collected with
 *        @ref mv_face_recognition_model_add() function
 *        face examples labeled with @a face_label.
 *
 * @since_tizen 3.0
 * @remarks Be aware that if this function is called before
 *          @ref mv_face_recognition_model_learn() function call, all or part of
 *          the required for learning data will be lost. It means that face
 *          image examples determined by the @a face_label label will be removed
 *          from the model and not taken into account when
 *          @ref mv_face_recognition_model_learn() will be called next time.
 * @remarks Call of this function will free all the memory has been allocated
 *          during previous @ref mv_face_recognition_model_add()
 *          calls for the corresponding @a face_label label.
 * @param [in] recognition_model    The handle to the recognition model for
 *                                  which face image examples will be reset.
 * @param [in] face_label           The label that identifies face for which
 *                                  examples will be removed from the
 *                                  @a recognition_model. If NULL, then all
 *                                  known by @a recognition_model face image
 *                                  examples will be removed
 * @return @c 0 on success, otherwise a negative error value
 * @retval #MEDIA_VISION_ERROR_NONE Successful
 * @retval #MEDIA_VISION_ERROR_INVALID_PARAMETER Invalid parameter
 * @retval #MEDIA_VISION_ERROR_KEY_NOT_AVAILABLE Key not available
 * @retval #MEDIA_VISION_ERROR_NOT_SUPPORTED Not supported
 *
 * @see mv_face_recognition_model_add()
 * @see mv_face_recognition_model_learn()
 */
int mv_face_recognition_model_reset(
	mv_face_recognition_model_h recognition_model,
	int *face_label);

/**
 * @brief Learns face recognition model.
 * @details Before you start learning process, face recognition models has to be
 *          filled with training data - face image examples. These examples has
 *          to be provided by
 *          @ref mv_face_recognition_model_add() function.
 *          Usually, recognition accuracy is increased when number of not
 *          identical examples is large. But it depends on the used learning
 *          algorithm.
 *
 * @since_tizen 3.0
 * @remarks Common flow is to collect face examples as much as possible, add
 *          them to the recognition model with
 *          @ref mv_face_recognition_model_add(), then call
 *          @ref mv_face_recognition_model_learn() for this recognition model to
 *          learn it (or update the model if updating is supported by the used
 *          algorithm).
 * @remarks Selection of the learning algorithm can be performed by setting
 *          corresponding attributes for the @a engine_cfg. You can check
 *          supported by @a engine_cfg attributes using
 *          @ref mv_engine_config_foreach_supported_attribute() function call.
 *          By default, Local Binary Patterns Histograms (LBPH) based
 *          recognition algorithm will be used.
 * @param [in]     engine_cfg           The handle to the configuration of
 *                                      engine will be used for learning of the
 *                                      recognition models. If NULL, then
 *                                      default settings will be used
 * @param [in,out] recognition_model    The model which will be learned. After
 *                                      learning process these model may be
 *                                      changed, so @ref mv_face_recognize()
 *                                      results may differ before and after
 *                                      method call respectively to the face
 *                                      examples collected for the
 *                                      @a recognition_model
 * @return @c 0 on success, otherwise a negative error value
 * @retval #MEDIA_VISION_ERROR_NONE Successful
 * @retval #MEDIA_VISION_ERROR_INVALID_PARAMETER Invalid parameter
 * @retval #MEDIA_VISION_ERROR_NO_DATA No data
 * @retval #MEDIA_VISION_ERROR_NOT_SUPPORTED Not supported
 *
 * @pre Create a face engine configuration handle by calling
 *      @ref mv_create_engine_config() and set supported parameters if
 *      needed. Or just set @a engine_cfg as NULL to learn with default settings
 * @pre Create a face recognition model handles by calling
 *      @ref mv_face_recognition_model_create() function
 * @pre Add face image examples to the @a recognition_model by calling
 *      @ref mv_face_recognition_model_add() function
 * @post If it is not planned to learn the model again, clear memory by
 *       @ref mv_face_recognition_model_reset() function
 * @post When model has been learned, it can be used for face recognition with
 *       @ref mv_face_recognize() function
 *
 * @see mv_face_recognition_model_add()
 * @see mv_face_recognition_model_reset()
 * @see mv_face_recognize()
 */
int mv_face_recognition_model_learn(
	mv_engine_config_h engine_cfg,
	mv_face_recognition_model_h recognition_model);

/**
 * @brief Queries labels list and number of labels had been learned by the model.
 *
 * @since_tizen 3.0
 * @remarks @a labels array has to be released using free().
 * @param [in]  recognition_model    The handle to the recognition model for
 *                                   which set of the learned labels will be
 *                                   queried
 * @param [out] labels               The array which will be filled with labels
 *                                   had been learned by the model
 * @param [out] number_of_labels     The number of labels in @a labels array
 * @return @c 0 on success, otherwise a negative error value
 * @retval #MEDIA_VISION_ERROR_NONE Successful
 * @retval #MEDIA_VISION_ERROR_INVALID_PARAMETER Invalid parameter
 * @retval #MEDIA_VISION_ERROR_NOT_SUPPORTED Not supported
 *
 * @pre Add face image examples with labels to the @a recognition_model by
 *      calling the @ref mv_face_recognition_model_add() function
 * @pre Learn the @a recognition_model by labeled examples using
 *      @ref mv_face_recognition_model_learn() function
 * @post @a labels array has to be freed in the function invoking code
 *
 * @see mv_face_recognition_model_add()
 * @see mv_face_recognition_model_reset()
 * @see mv_face_recognition_model_learn()
 */
int mv_face_recognition_model_query_labels(
	mv_face_recognition_model_h recognition_model,
	int **labels,
	unsigned int *number_of_labels);

/***************************/
/* Tracking model behavior */
/***************************/

/**
 * @brief Calls this function to create a face tracking model handle.
 * @details Use this function to create default face tracking model handle.
 *          After creation this handle has to be initialized with
 *          @ref mv_face_tracking_model_prepare() function to provide
 *          appropriate results of face tracking functionality. When handle is
 *          prepared, it is possible to use it for tracking on continuous
 *          sequence of the sources. Call @ref mv_face_tracking_model_prepare()
 *          function each time before starting tracking on the new sequence.
 *          The exception is situation when the new sequence is continuation
 *          of the previous sequence for which model has been tracked.
 *
 * @since_tizen 3.0
 * @param [out] tracking_model    The pointer to the handle to the tracking
 *                                model that will be created
 * @return @c 0 on success, otherwise a negative error value
 * @retval #MEDIA_VISION_ERROR_NONE Successful
 * @retval #MEDIA_VISION_ERROR_INVALID_PARAMETER Invalid parameter
 * @retval #MEDIA_VISION_ERROR_OUT_OF_MEMORY Out of memory
 * @retval #MEDIA_VISION_ERROR_NOT_SUPPORTED Not supported
 *
 * @post Model can be loaded from the file after creation. Use
 *       @ref mv_face_tracking_model_load() function to load it from file
 * @post Use @ref mv_face_tracking_model_prepare() function before tracking on
 *       the new video or continuous images sequence
 * @post Release @a tracking_model by using
 *       @ref mv_face_tracking_model_destroy() function when it is not needed
 *       anymore
 *
 * @see mv_face_tracking_model_destroy()
 * @see mv_face_tracking_model_prepare()
 * @see mv_face_tracking_model_load()
 */
int mv_face_tracking_model_create(
	mv_face_tracking_model_h *tracking_model);

/**
 * @brief Calls this function to destroy the face tracking model handle and
 *        release all its resources.
 *
 * @since_tizen 3.0
 * @param [in] tracking_model    The handle to the face tracking model that
 *                               will be destroyed
 * @return @c 0 on success, otherwise a negative error value
 * @retval #MEDIA_VISION_ERROR_NONE Successful
 * @retval #MEDIA_VISION_ERROR_INVALID_PARAMETER Invalid parameter
 * @retval #MEDIA_VISION_ERROR_NOT_SUPPORTED Not supported
 *
 * @pre Create tracking model by using @ref mv_face_tracking_model_create()
 *
 * @see mv_face_tracking_model_create()
 */
int mv_face_tracking_model_destroy(
	mv_face_tracking_model_h tracking_model);

/**
 * @brief Calls this function to initialize tracking model by the location of the
 *        face to be tracked.
 * @details This function is usually called once after tracking model is created
 *          and each time before tracking is started for the new sequence of
 *          sources which is not the direct continuation of the sequence for
 *          which tracking has been performed before. But it is allowed to call
 *          it between tracking sessions to allow Media Vision start to track
 *          more accurately.
 *
 * @since_tizen 3.0
 * @param [in] tracking_model    The handle to the tracking model that will be
 *                               prepared for tracking on new video or image
 *                               sequence
 * @param [in] engine_cfg        The handle to the configuration of engine
 *                               will be used for model preparing. If NULL, then
 *                               default settings will be used.
 * @param [in] source            The handle to the source where face @a location
 *                               is specified. Usually it is the first frame of
 *                               the video or the first image in the continuous
 *                               image sequence planned to be used for tracking
 * @param [in] location          The quadrangle-shaped location (actually,
 *                               rectangle can be used) determining position
 *                               of the face to be tracked on the @a source. If
 *                               @c NULL, then tracking model will try to find
 *                               previously tracked face by itself. Don't set
 *                               NULL when called first time for the tracking
 *                               model.
 * @return @c 0 on success, otherwise a negative error value
 * @retval #MEDIA_VISION_ERROR_NONE Successful
 * @retval #MEDIA_VISION_ERROR_INVALID_PARAMETER Invalid parameter
 * @retval #MEDIA_VISION_ERROR_NOT_SUPPORTED Not supported
 *
 * @pre Create a face tracking model handle by calling
 *      @ref mv_face_tracking_model_create() function
 * @pre Create a source handle by calling @ref mv_create_source() function
 * @post When model is prepared, @ref mv_face_track() function can be used to
 *       track on the video or continuous image sequence
 *
 * @see mv_face_tracking_model_create()
 * @see mv_face_track()
 */
int mv_face_tracking_model_prepare(
	mv_face_tracking_model_h tracking_model,
	mv_engine_config_h engine_cfg,
	mv_source_h source,
	mv_quadrangle_s *location);

/**
 * @brief Calls this function to make a copy of existed tracking model handle and
 *        clone all its resources to the copy.
 *
 * @since_tizen 3.0
 * @remarks Cloning performs not only handle copy, but also copies all internal
 *          resources of the model. @a dst must be released using
 *          mv_face_tracking_model_destroy().
 * @param [in]     src    The handle to the tracking model to be copied
 * @param [out]    dst    The handle to the copy of existed tracking model
 *                        specified as @a src
 * @return @c 0 on success, otherwise a negative error value
 * @retval #MEDIA_VISION_ERROR_NONE Successful
 * @retval #MEDIA_VISION_ERROR_INVALID_PARAMETER Invalid parameter
 * @retval #MEDIA_VISION_ERROR_OUT_OF_MEMORY Out of memory
 * @retval #MEDIA_VISION_ERROR_NOT_SUPPORTED Not supported
 *
 * @pre Create face tracking @a src handle by calling
 *      @ref mv_face_tracking_model_create()
 *
 * @see mv_face_tracking_model_create()
 */
int mv_face_tracking_model_clone(
	mv_face_tracking_model_h src,
	mv_face_tracking_model_h *dst);

/**
 * @brief Calls this method to save tracking model to the file.
 *
 * @since_tizen 3.0
 * @remarks @a tracking_model is saved to the absolute path directory.
 *          Use @ref app_get_data_path for the private app storage path.
 *          After model is saved to the file, it can be loaded from this file
 *          with @ref mv_face_tracking_model_load() function.
 * @param [in] file_name         Name of the path/file to save the model
 * @param [in] tracking_model    The handle to the tracking model to be
 *                               saved to the file
 * @return @c 0 on success, otherwise a negative error value
 * @retval #MEDIA_VISION_ERROR_NONE Successful
 * @retval #MEDIA_VISION_ERROR_INVALID_PARAMETER Invalid parameter
 * @retval #MEDIA_VISION_ERROR_INVALID_OPERATION Invalid operation
 * @retval #MEDIA_VISION_ERROR_INVALID_PATH Invalid path
 * @retval #MEDIA_VISION_ERROR_PERMISSION_DENIED Not permitted
 * @retval #MEDIA_VISION_ERROR_NOT_SUPPORTED_FORMAT Not supported model format
 * @retval #MEDIA_VISION_ERROR_NOT_SUPPORTED Not supported
 *
 * @pre Create a face tracking handle by calling
 *      @ref mv_face_tracking_model_create()
 * @post Saved model can be loaded from file using
 *       @ref mv_face_tracking_model_load() function
 *
 * @see mv_face_tracking_model_load()
 * @see mv_face_tracking_model_create()
 * @see app_get_data_path()
 */
int mv_face_tracking_model_save(
	const char *file_name,
	mv_face_tracking_model_h tracking_model);

/**
 * @brief Calls this method to load a tracking model from file.
 *
 * @since_tizen 3.0
 * @remarks @a tracking_model is loaded from the absolute path directory.
 *          Use @ref app_get_data_path for the private app storage path.
 *          @a tracking_model must be destroyed using
 *          @ref mv_face_tracking_model_destroy.
 * @param [in] file_name         Name of path/file to load the model
 * @param [out] tracking_model   The handle to the tracking model to be
 *                               loaded from file
 * @return @c 0 on success, otherwise a negative error value
 * @retval #MEDIA_VISION_ERROR_NONE Successful
 * @retval #MEDIA_VISION_ERROR_INVALID_PARAMETER Invalid parameter
 * @retval #MEDIA_VISION_ERROR_INVALID_OPERATION Invalid operation
 * @retval #MEDIA_VISION_ERROR_INVALID_PATH Invalid path
 * @retval #MEDIA_VISION_ERROR_PERMISSION_DENIED Not permitted
 * @retval #MEDIA_VISION_ERROR_OUT_OF_MEMORY Out of memory
 * @retval #MEDIA_VISION_ERROR_NOT_SUPPORTED_FORMAT Not supported model format
 * @retval #MEDIA_VISION_ERROR_NOT_SUPPORTED Not supported
 *
 * @pre Models has been saved by @ref mv_face_tracking_model_save() function
 *      can be loaded with this function
 * @post After model has been loaded and if further tracking will be performed
 *       on the video which is not continuation of the last tracking performed
 *       for the model, it is recommended to call
 *       @ref mv_face_tracking_model_prepare() function
 *
 * @see mv_face_tracking_model_save()
 * @see mv_face_tracking_model_destroy()
 * @see app_get_data_path()
 */
int mv_face_tracking_model_load(
	const char *file_name,
	mv_face_tracking_model_h *tracking_model);

/**
 * @}
 */

#ifdef __cplusplus
}
#endif /* __cplusplus */

#endif /* __TIZEN_MEDIAVISION_FACE_H__ */
