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#ifndef __UNIFIED_CAMERA_ACCESS_CAM_H
#define __UNIFIED_CAMERA_ACCESS_CAM_H
#include <stdint.h>
#ifdef __cplusplus
extern "C" {
#endif
/**
* \file uca-cam.h
* \brief Abstract camera model
*
* The uca_camera_t structure represents a common interface for cameras regardless of
* their connectivity. Each camera that adheres to this model must provide an
* initialization function implementing uca_cam_init() that probes the device
* and sets all function pointers to their respective implementations.
*/
struct uca_camera_t;
struct uca_grabber_t;
struct uca_property_t;
enum uca_property_ids;
/**
* Describes the current state of the camera.
*/
enum uca_cam_state {
UCA_CAM_ERROR, /**< Camera is not working correctly */
UCA_CAM_CONFIGURABLE, /**< Camera can be configured and is not recording */
UCA_CAM_ARMED, /**< Camera is ready for recording */
UCA_CAM_RECORDING, /**< Camera is currently recording */
};
/*
* --- non-virtual methods ----------------------------------------------------
*/
/**
* Allocates buffer memory for the internal frame grabber.
*
* The allocation is just a hint to the underlying camera driver. It might
* ignore this or pass this information on to a related frame grabber.
*
* \param[in] cam A camera structure.
*
* \param[in] n_buffers Number of sub-buffers with size frame_width*frame_height.
*/
uint32_t uca_cam_alloc(struct uca_camera_t *cam, uint32_t n_buffers);
/**
* Retrieve current state of the camera.
*
* \param[in] cam A camera structure.
*
* \return A value from the uca_cam_state enum representing the current state of
* the camera.
*/
enum uca_cam_state uca_cam_get_state(struct uca_camera_t *cam);
/*
* --- virtual methods --------------------------------------------------------
*/
/**
* Function pointer for camera probing and initialization.
*
* \param[out] cam On success, *cam holds the newly created uca_camera_t
* structure.
*
* \param[in] grabber Grabber structure to access the cam. Can be NULL to
* specify devices without frame grabber access.
*
* \return
* UCA_ERR_INIT_NOT_FOUND if camera is not found or could not be initialized
*
* \note This is a private function and should be called exclusively by uca_init().
*/
typedef uint32_t (*uca_cam_init) (struct uca_camera_t **cam, struct uca_grabber_t *grabber);
/**
* \brief Function pointer to free camera resources.
*
* \param[in] cam The camera to close.
*
* \note This is a private function and should be called exclusively by uca_init().
*/
typedef uint32_t (*uca_cam_destroy) (struct uca_camera_t *cam);
/**
* Function pointer to set a camera property.
*
* \param[in] cam The camera whose properties are to be set.
*
* \param[in] property ID of the property as defined in XXX
*
* \param[out] data Where to read the property's value from
*
* \return UCA_ERR_PROP_INVALID if property is not supported on the camera or
* UCA_ERR_PROP_VALUE_OUT_OF_RANGE if value cannot be set.
*/
typedef uint32_t (*uca_cam_set_property) (struct uca_camera_t *cam, enum uca_property_ids property, void *data);
/**
* Function pointer to get a property.
*
* \param[in] cam The camera whose properties are to be retrieved.
*
* \param[in] property ID of the property as defined in XXX
*
* \param[out] data Where to store the property's value
*
* \param[in] num Number of bytes of string storage. Ignored for uca_uint8t
* and uca_uint32t properties.
*
* \return UCA_ERR_PROP_INVALID if property is not supported on the camera
*/
typedef uint32_t (*uca_cam_get_property) (struct uca_camera_t *cam, enum uca_property_ids property, void *data, size_t num);
/**
* Begin recording.
*
* Usually this also involves the frame acquisition of the frame grabber but is
* hidden by this function.
*/
typedef uint32_t (*uca_cam_start_recording) (struct uca_camera_t *cam);
/**
* Stop recording.
*/
typedef uint32_t (*uca_cam_stop_recording) (struct uca_camera_t *cam);
/**
* \brief Grab one image from the camera
*
* The grabbing involves a memory copy because we might have to decode the image
* coming from the camera, which the frame grabber is not able to do.
*
* \param[in] buffer Destination buffer
*
*/
typedef uint32_t (*uca_cam_grab) (struct uca_camera_t *cam, char *buffer);
/**
* Represents a camera abstraction, that concrete cameras must implement.
*/
struct uca_camera_t {
/**
* Points to the next available camera in a linked-list fashion.
*
* End of list is specified with next == NULL.
*/
struct uca_camera_t *next;
/* Function pointers to camera-specific methods */
/**
* Method to set a property.
* \see uca_cam_set_property
*/
uca_cam_set_property set_property;
/**
* Method to get a property.
* \see uca_cam_get_property
*/
uca_cam_get_property get_property;
/**
* Method to start recording.
* \see uca_cam_start_recording
*/
uca_cam_start_recording start_recording;
/**
* Method to stop recording.
* \see uca_cam_stop_recording
*/
uca_cam_stop_recording stop_recording;
/**
* Method to grab a frame.
* \see uca_cam_grab
*/
uca_cam_grab grab;
/* Private */
/**
* Method to close the camera.
* \see uca_cam_destroy
*/
uca_cam_destroy destroy;
struct uca_grabber_t *grabber; /**< grabber associated with this camera */
enum uca_cam_state state; /**< camera state */
uint32_t frame_width; /**< current frame width */
uint32_t frame_height; /**< current frame height */
uint32_t current_frame; /**< last grabbed frame number */
void *user; /**< private user data to be used by the camera driver */
};
#ifdef __cplusplus
}
#endif
#endif
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