Tizen Native API
5.0
|
Video surveillance module.
Required Header
#include <mv_surveillance.h>
Related Features
This API is related with the following features:
- http://tizen.org/feature/vision.image_recognition
- http://tizen.org/feature/vision.face_recognition
It is recommended to design feature related codes in your application for reliability.
You can check if a device supports the related features for this API by using System Information, thereby controlling the procedure of your application.
To ensure your application is only running on the device with specific features, please define the features in your manifest file using the manifest editor in the SDK.
More details on featuring your application can be found from Feature Element.
Overview
Media Vision Surveillance provides functionality can be utilized for creation of video surveillance systems. The main idea underlying surveillance is event subscription model. By default, supported event types are described in Media Vision Surveillance Event Types section. mv_surveillance_subscribe_event_trigger() function has to be used to create subscription to the particular event trigger. Triggers are handled by mv_surveillance_event_trigger_h type. Such type handlers can be created with mv_surveillance_event_trigger_create() function and destroyed with mv_surveillance_event_trigger_destroy() function. Once event trigger subscription is created, corresponding mv_surveillance_event_occurred_cb() callback will be invoked each time when event is detected, i.e. trigger is activated. mv_surveillance_result_h event detection result handler will be passed to the callback together with identifier of the video stream where event was detected and mv_source_h handler containing frame in which detection was performed. It is possible to retrieve specific to event type result values using mv_surveillance_result_h handler. In the mv_surveillance_get_result_value() function documentation can be found detailed description of result values retrieving. Following table contains general events and corresponding event detection results can be obtained by this approach:
Before subscription of the event trigger with mv_surveillance_subscribe_event_trigger() call it is possible to create mv_engine_config_h handle and configure following attributes:
- MV_SURVEILLANCE_SKIP_FRAMES_COUNT to setup number of frames will be ignored by event trigger;
- MV_SURVEILLANCE_MOVEMENT_DETECTION_THRESHOLD to specify sensitivity of the MV_SURVEILLANCE_EVENT_TYPE_MOVEMENT_DETECTED event detection;
- MV_SURVEILLANCE_FACE_RECOGNITION_MODEL_FILE_PATH to specify the file where face recognition model to be used for recognition is stored.
Created engine config has to be used as a parameter of mv_surveillance_subscribe_event_trigger() to apply the configuration. If NULL will be passed instead of valid mv_engine_config_h handle, then default attribute values will be used for subscriptions. To make surveillance system work with video sequences mv_surveillance_push_source() function has to be used for each frame in the sequence in the correct order. Multiple video sources can be supported by the system. To distinguish different video sources unique stream identifier has to be assigned to each subscription. Then, particular identifier can be passed as a parameter to the mv_surveillance_push_source() function. After pushing the source to the surveillance system, it will notify all triggers which were subscribed to process frames coming from video stream which source has been pushed. If trigger(s) is(are) activated on the source, then corresponding callback(s) of mv_surveillance_event_occurred_cb() type will be called. Additionally, region where event detection will be performed by the triggers can be set with mv_surveillance_set_event_trigger_roi() function and gotten with mv_surveillance_get_event_trigger_roi(). ROI is specified independently for the each event trigger, so it is possible to detect events of different types in the different parts of the incoming frames. Event trigger subscription can be stopped any time using mv_surveillance_unsubscribe_event_trigger() function. Additionally, mv_surveillance_foreach_supported_event_type() and mv_surveillance_foreach_event_result_name() functions can be found useful if it is required to obtain supported event types list or result value names list dynamically.
Functions | |
int | mv_surveillance_event_trigger_create (const char *event_type, mv_surveillance_event_trigger_h *trigger) |
Creates surveillance event trigger handle. | |
int | mv_surveillance_event_trigger_destroy (mv_surveillance_event_trigger_h trigger) |
Destroys the surveillance event trigger handle and releases all its resources. | |
int | mv_surveillance_get_event_trigger_type (mv_surveillance_event_trigger_h trigger, char **event_type) |
Gets the surveillance event trigger type as character string. | |
int | mv_surveillance_set_event_trigger_roi (mv_surveillance_event_trigger_h trigger, int number_of_points, mv_point_s *roi) |
Sets ROI (Region Of Interest) to the event trigger. | |
int | mv_surveillance_get_event_trigger_roi (mv_surveillance_event_trigger_h trigger, int *number_of_points, mv_point_s **roi) |
Gets ROI (Region Of Interest) from the event trigger. | |
int | mv_surveillance_subscribe_event_trigger (mv_surveillance_event_trigger_h trigger, int video_stream_id, mv_engine_config_h engine_cfg, mv_surveillance_event_occurred_cb callback, void *user_data) |
Subscribes trigger to process sources pushed from video identified by video_stream_id. | |
int | mv_surveillance_unsubscribe_event_trigger (mv_surveillance_event_trigger_h trigger, int video_stream_id) |
Unsubscribes trigger from the event and stop calling callback. | |
int | mv_surveillance_push_source (mv_source_h source, int video_stream_id) |
Pushes source to the surveillance system to detect events. | |
int | mv_surveillance_foreach_supported_event_type (mv_surveillance_event_type_cb callback, void *user_data) |
Starts traversing through list of supported event types. | |
int | mv_surveillance_foreach_event_result_name (const char *event_type, mv_surveillance_event_result_name_cb callback, void *user_data) |
Starts traversing through list of supported event result value names. | |
int | mv_surveillance_get_result_value (mv_surveillance_result_h result, const char *name, void *value) |
Gets result value. | |
Typedefs | |
typedef void * | mv_surveillance_event_trigger_h |
The handle to event trigger. | |
typedef void * | mv_surveillance_result_h |
The handle to event trigger activation result. | |
typedef void(* | mv_surveillance_event_occurred_cb )(mv_surveillance_event_trigger_h trigger, mv_source_h source, int video_stream_id, mv_surveillance_result_h event_result, void *user_data) |
Called when event trigger activation has been detected. | |
typedef bool(* | mv_surveillance_event_type_cb )(const char *event_type, void *user_data) |
Called to get the information once for each supported event type. | |
typedef bool(* | mv_surveillance_event_result_name_cb )(const char *name, void *user_data) |
Called to get the result name from the triggered event. | |
Defines | |
#define | MV_SURVEILLANCE_FACE_RECOGNITION_MODEL_FILE_PATH "MV_SURVEILLANCE_FACE_RECOGNITION_MODEL_FILE_PATH" |
Defines MV_SURVEILLANCE_FACE_RECOGNITION_MODEL_FILE_PATH to set face recognition model file path. It is an attribute of the engine configuration. | |
#define | MV_SURVEILLANCE_MOVEMENT_DETECTION_THRESHOLD "MV_SURVEILLANCE_MOVEMENT_DETECTION_THRESHOLD" |
Defines MV_SURVEILLANCE_MOVEMENT_DETECTION_THRESHOLD to set movement detection threshold. It is an attribute of the engine configuration. | |
#define | MV_SURVEILLANCE_SKIP_FRAMES_COUNT "MV_SURVEILLANCE_SKIP_FRAMES_COUNT" |
Defines MV_SURVEILLANCE_SKIP_FRAMES_COUNT to set how many frames will be skipped during push source. It is an attribute of the engine configuration. |
Define Documentation
#define MV_SURVEILLANCE_FACE_RECOGNITION_MODEL_FILE_PATH "MV_SURVEILLANCE_FACE_RECOGNITION_MODEL_FILE_PATH" |
Defines MV_SURVEILLANCE_FACE_RECOGNITION_MODEL_FILE_PATH to set face recognition model file path. It is an attribute of the engine configuration.
This value HAS TO BE set in engine configuration before subscription on MV_SURVEILLANCE_EVENT_TYPE_PERSON_RECOGNIZED event trigger
- Since :
- 3.0
#define MV_SURVEILLANCE_MOVEMENT_DETECTION_THRESHOLD "MV_SURVEILLANCE_MOVEMENT_DETECTION_THRESHOLD" |
Defines MV_SURVEILLANCE_MOVEMENT_DETECTION_THRESHOLD to set movement detection threshold. It is an attribute of the engine configuration.
This value might be set in engine configuration before subscription on MV_SURVEILLANCE_EVENT_TYPE_MOVEMENT_DETECTED event trigger to specify sensitivity of the movement detector. This value has to be integer in 0..255 range where 255 means that no movements will be detected, and 0 means that all frame changes will be interpreted as movements. Default value is 10.
- Since :
- 3.0
#define MV_SURVEILLANCE_SKIP_FRAMES_COUNT "MV_SURVEILLANCE_SKIP_FRAMES_COUNT" |
Defines MV_SURVEILLANCE_SKIP_FRAMES_COUNT to set how many frames will be skipped during push source. It is an attribute of the engine configuration.
This integer value might be set in engine configuration to specify number of mv_surveillance_push_source() function calls will be ignored by subscription of the event trigger. Default value is 0. It means that no frames will be skipped and all mv_surveillance_push_source() function calls will be processed.
- Since :
- 3.0
Typedef Documentation
typedef void(* mv_surveillance_event_occurred_cb)(mv_surveillance_event_trigger_h trigger, mv_source_h source, int video_stream_id, mv_surveillance_result_h event_result, void *user_data) |
Called when event trigger activation has been detected.
- Since :
- 3.0
- Remarks:
- Handle event_result is valid only inside callback
- Parameters:
-
[in] trigger The event trigger handle [in] source The handle to the media source [in] video_stream_id The identifier of the video source where event has been detected [in] event_result The event result passed from the mv_surveillance_subscribe_event_trigger() [in] user_data The user data passed from the mv_surveillance_subscribe_event_trigger() function
- Precondition:
- Callback can be invoked only after mv_surveillance_subscribe_event_trigger() was called for particular event trigger.
typedef bool(* mv_surveillance_event_result_name_cb)(const char *name, void *user_data) |
Called to get the result name from the triggered event.
- Since :
- 3.0
- Remarks:
- Don't release memory of value_name
- Parameters:
-
[in] name Character string containing the name of value that can be obtained from mv_surveillance_result_h handle by mv_surveillance_get_result_value() function [in] user_data The user data passed from the mv_surveillance_foreach_event_result_name() function
- Returns:
true
to continue with the next iteration of the loop,
otherwisefalse
to break out of the loop
- Precondition:
- mv_surveillance_foreach_event_result_name() will invoke this callback
typedef void* mv_surveillance_event_trigger_h |
The handle to event trigger.
- Since :
- 3.0
- Remarks:
- See supported event types and their descriptions in Media Vision Surveillance Event Types documentation section. Also the list of supported events can be obtained using mv_surveillance_foreach_supported_event_type() function
typedef bool(* mv_surveillance_event_type_cb)(const char *event_type, void *user_data) |
Called to get the information once for each supported event type.
- Since :
- 3.0
- Remarks:
- Don't release memory of event_type
- Parameters:
-
[in] event_type Character string containing name of the event type [in] user_data The user data passed from the mv_surveillance_foreach_supported_event_type() function
- Returns:
true
to continue with the next iteration of the loop,
otherwisefalse
to break out of the loop
- Precondition:
- mv_surveillance_foreach_supported_event_type() will invoke this callback
typedef void* mv_surveillance_result_h |
The handle to event trigger activation result.
Result is a handle to the output values which are specific for each event. See the output values names in the event types descriptions located in Media Vision Surveillance Event Types documentation section. Result values can be gotten by mv_surveillance_get_result_value() function one by one in order specified in the event description ( the same order of event value names is supported by mv_surveillance_foreach_event_result_name() function). This pointer will be destroyed when mv_surveillance_event_occurred_cb passed.
- Since :
- 3.0
Function Documentation
int mv_surveillance_event_trigger_create | ( | const char * | event_type, |
mv_surveillance_event_trigger_h * | trigger | ||
) |
Creates surveillance event trigger handle.
- Since :
- 3.0
- Remarks:
- List of supported event types can be obtained by mv_surveillance_foreach_supported_event_type function
- You must release trigger by using mv_surveillance_event_trigger_destroy()
- Parameters:
-
[in] event_type Name of the event type to be supported by the trigger [out] trigger A new handle to the event trigger
- Returns:
0
on success, otherwise a negative error value
- Return values:
-
MEDIA_VISION_ERROR_NONE Successful MEDIA_VISION_ERROR_INVALID_PARAMETER Invalid parameter MEDIA_VISION_ERROR_OUT_OF_MEMORY Out of memory MEDIA_VISION_ERROR_NOT_SUPPORTED Not supported
Destroys the surveillance event trigger handle and releases all its resources.
- Since :
- 3.0
- Parameters:
-
[in] trigger The handle to the event trigger to be destroyed
- Returns:
0
on success, otherwise a negative error value
- Return values:
-
MEDIA_VISION_ERROR_NONE Successful MEDIA_VISION_ERROR_INVALID_PARAMETER Invalid parameter MEDIA_VISION_ERROR_NOT_SUPPORTED Not supported
- See also:
- mv_surveillance_event_trigger_create
int mv_surveillance_foreach_event_result_name | ( | const char * | event_type, |
mv_surveillance_event_result_name_cb | callback, | ||
void * | user_data | ||
) |
Starts traversing through list of supported event result value names.
- Since :
- 3.0
- Remarks:
- Supported event types, event result value names and their descriptions can be found in Media Vision Surveillance Event Types documentation section
- Parameters:
-
[in] event_type The name of the event type for which result value names will be passed to the callback. Can be set NULL
. If setNULL
then all supported event result value names will be traversed[in] callback The callback function to be called for each supported event result value name [in] user_data The user data to be passed to the callback function
- Returns:
0
on success, otherwise a negative error value
- Return values:
-
MEDIA_VISION_ERROR_NONE Successful MEDIA_VISION_ERROR_INVALID_PARAMETER Invalid parameter MEDIA_VISION_ERROR_NOT_SUPPORTED Not supported
int mv_surveillance_foreach_supported_event_type | ( | mv_surveillance_event_type_cb | callback, |
void * | user_data | ||
) |
Starts traversing through list of supported event types.
- Since :
- 3.0
- Remarks:
- Supported event types and their descriptions can be found in Media Vision Surveillance Event Types documentation section
- Parameters:
-
[in] callback The callback function to be called for each supported event type [in] user_data The user data to be passed to the callback function
- Returns:
0
on success, otherwise a negative error value
- Return values:
-
MEDIA_VISION_ERROR_NONE Successful MEDIA_VISION_ERROR_INVALID_PARAMETER Invalid parameter MEDIA_VISION_ERROR_NOT_SUPPORTED Not supported
int mv_surveillance_get_event_trigger_roi | ( | mv_surveillance_event_trigger_h | trigger, |
int * | number_of_points, | ||
mv_point_s ** | roi | ||
) |
Gets ROI (Region Of Interest) from the event trigger.
- Since :
- 3.0
- Remarks:
- If mv_surveillance_set_event_trigger_roi() has been never called for trigger, then number_of_points output value will be zero and roi pointer will be not changed.
- Parameters:
-
[in] trigger The handle to the event trigger [out] number_of_points The number of ROI points [out] roi The output array with ROI points
- Returns:
0
on success, otherwise a negative error value
- Return values:
-
MEDIA_VISION_ERROR_NONE Successful MEDIA_VISION_ERROR_INVALID_PARAMETER Invalid parameter MEDIA_VISION_ERROR_NOT_SUPPORTED Not supported
- Precondition:
- Event trigger has to be created by mv_surveillance_event_trigger_create() function
- Postcondition:
- Memory for roi array must be released
int mv_surveillance_get_event_trigger_type | ( | mv_surveillance_event_trigger_h | trigger, |
char ** | event_type | ||
) |
Gets the surveillance event trigger type as character string.
- Since :
- 3.0
- Remarks:
- The event_type should be freed using free()
- Parameters:
-
[in] trigger The handle to the event trigger [out] event_type The pointer to the character string which will be filled by textual name of the event type
- Returns:
0
on success, otherwise a negative error value
- Return values:
-
MEDIA_VISION_ERROR_NONE Successful MEDIA_VISION_ERROR_INVALID_PARAMETER Invalid parameter MEDIA_VISION_ERROR_NOT_SUPPORTED Not supported
- Precondition:
- Event trigger has to be created by mv_surveillance_event_trigger_create() function
int mv_surveillance_get_result_value | ( | mv_surveillance_result_h | result, |
const char * | name, | ||
void * | value | ||
) |
Gets result value.
See the output values names in the event types descriptions located in Media Vision Surveillance Event Types documentation section.
- Since :
- 3.0
- Remarks:
- The name can be obtained by mv_surveillance_foreach_event_result_name function
- Parameters:
-
[in] result The handle to the event result [in] name The name of the value to be gotten [in,out] value The pointer to variable which will be filled by result value. To find the type of value please refer to the Media Vision Surveillance Event Types documentation section
- Returns:
0
on success, otherwise a negative error value
- Return values:
-
MEDIA_VISION_ERROR_NONE Successful MEDIA_VISION_ERROR_INVALID_PARAMETER Invalid parameter MEDIA_VISION_ERROR_NOT_SUPPORTED Not supported
- Precondition:
- Memory for value has to be allocated
int mv_surveillance_push_source | ( | mv_source_h | source, |
int | video_stream_id | ||
) |
Pushes source to the surveillance system to detect events.
mv_surveillance_event_occurred_cb() will be called when any subscribing event detected.
- Since :
- 3.0
- Remarks:
- mv_surveillance_set_event_trigger_roi() function can be used to specify the polygon region where event can be detected only
- Parameters:
-
[in] source The handle to the media source [in] video_stream_id The identifier of video stream from which source is coming
- Returns:
0
on success, otherwise a negative error value
- Return values:
-
MEDIA_VISION_ERROR_NONE Successful MEDIA_VISION_ERROR_INVALID_PARAMETER Invalid parameter MEDIA_VISION_ERROR_NOT_SUPPORTED Not supported
- Precondition:
- To receive surveillance results, some event triggers has to be subscribed by mv_surveillance_subscribe_event_trigger() function before mv_surveillance_push_source() calls
- Before calling of this method source has to be correctly filled. mv_source_fill_by_media_packet(), mv_source_fill_by_buffer() functions can be used to fill source
int mv_surveillance_set_event_trigger_roi | ( | mv_surveillance_event_trigger_h | trigger, |
int | number_of_points, | ||
mv_point_s * | roi | ||
) |
Sets ROI (Region Of Interest) to the event trigger.
When ROI is set for the event trigger, then event check for this trigger will be performed only inside the polygonal region determined by roi parameter. If this method has been never called for the trigger, then event will be checked for the whole input frame (event check is performed for each mv_surveillance_push_source() function call). It is possible to change the ROI between mv_surveillance_push_source() calls.
- Since :
- 3.0
- Parameters:
-
[in] trigger The handle to the event trigger [in] number_of_points The number of ROI points [in] roi The input array with ROI points
- Returns:
0
on success, otherwise a negative error value
- Return values:
-
MEDIA_VISION_ERROR_NONE Successful MEDIA_VISION_ERROR_INVALID_PARAMETER Invalid parameter MEDIA_VISION_ERROR_NOT_SUPPORTED Not supported
- Precondition:
- Event trigger has to be created by mv_surveillance_event_trigger_create() function
int mv_surveillance_subscribe_event_trigger | ( | mv_surveillance_event_trigger_h | trigger, |
int | video_stream_id, | ||
mv_engine_config_h | engine_cfg, | ||
mv_surveillance_event_occurred_cb | callback, | ||
void * | user_data | ||
) |
Subscribes trigger to process sources pushed from video identified by video_stream_id.
When trigger is subscribed, then each time when function mv_surveillance_push_source() is called for video_stream_id, event occurrence is checked. If this check is successful, callback is invoked. Details on occurred event can be obtained using mv_surveillance_result_h handle from callback.
- Since :
- 3.0
- Remarks:
- Use mv_surveillance_unsubscribe_event_trigger() function for the same trigger and video_stream_id parameters to stop subscription.
- Parameters:
-
[in] trigger The handle to the event trigger activating calls of the callback function [in] video_stream_id The identifier of the video stream for which event trigger activation will be checked [in] engine_cfg The engine configuration of the event [in] callback Callback to be called each time when event occurrence is detected [in] user_data The user data to be passed to the callback function
- Returns:
0
on success, otherwise a negative error value
- Return values:
-
MEDIA_VISION_ERROR_NONE Successful MEDIA_VISION_ERROR_INVALID_PARAMETER Invalid parameter MEDIA_VISION_ERROR_NOT_SUPPORTED Not supported
- Postcondition:
- mv_surveillance_event_occurred_cb will be called each time trigger is activated after mv_surveillance_push_source() call
int mv_surveillance_unsubscribe_event_trigger | ( | mv_surveillance_event_trigger_h | trigger, |
int | video_stream_id | ||
) |
Unsubscribes trigger from the event and stop calling callback.
- Since :
- 3.0
- Remarks:
- To start handling trigger activation use mv_surveillance_subscribe_event_trigger().
- Parameters:
-
[in] trigger The handle to the event trigger for which subscription will be stopped [in] video_stream_id The identifier of the video source for which subscription will be stopped
- Returns:
0
on success, otherwise a negative error value
- Return values:
-
MEDIA_VISION_ERROR_NONE Successful MEDIA_VISION_ERROR_INVALID_PARAMETER Invalid parameter MEDIA_VISION_ERROR_NOT_SUPPORTED Not supported
- Precondition:
- To stop subscription it has to be created earlier with mv_surveillance_subscribe_event_trigger() function