Internally spawned thread class to provide continuous grabbing without drop frames. More...

#include <DCGrabberThread.h>

Inheritance diagram for icl::io::dc::DCGrabberThread:

Public Member Functions
virtual ICLIO_API void	run ()
	the thread function (moved frames)
ICLIO_API void	resetBus ()
	internally calls dc1394_reset_bus (not save!)
Static Public Member Functions
static ICLIO_API void	stopAllGrabberThreads ()
	called by the signal handler to stop all grabber threads
Private Member Functions
	DCGrabberThread (dc1394camera_t c, DCDeviceOptions options)
	private constructor )can only be called by icl::DCGrabber
	~DCGrabberThread ()
	Destructor.
void	getCurrentImage (core::ImgBase ppoDst, core::ImgBase ppoDstTmp, bool &desiredParamsFullfilled, const utils::Size &desiredSizeHint, core::format desiredFormatHint, core::depth desiredDepthHint, dc1394color_filter_t bayerLayout, dc1394bayer_method_t bayerMethod=DC1394_BAYER_METHOD_BILINEAR)
	private image access function
void	getCurrentImage (core::ImgBase **ppoDst, dc1394color_filter_t bayerLayout, dc1394bayer_method_t bayerMethod=DC1394_BAYER_METHOD_BILINEAR)
	returns the current image directly (if no desried parameters are set)
dc1394video_frame_t *	waitForNextImageFrame ()
Private Attributes
DCFrameQueue *	m_poFrameQueue
	internally used DCFrameQueue object
dc1394camera_t *	m_poCam
	Associated camera.
std::vector< icl8u >	m_oRGBInterleavedBuffer
	internally used buffer for RGB-Bayer image conversion
DCDeviceOptions *	m_poOptions
	Parents DCGrabbers options pointer.
utils::Time	m_lastFramesTimeStamp
	to remember the time stamp of the last frame grabbed
Friends
class	icl::io::DCGrabber
	A DCGrabberThread can only be instantiated by a DCGrabber.

Detailed Description

Internally spawned thread class to provide continuous grabbing without drop frames.

Each DCGrabber instance uses a DCGrabberThread, which continuously dequeues and enqueus frames. Each frame can either be inside of the DMA queue or inside of the DCGrabberThreads wrapped DCFrameQueue at on time. The following ASCII art should illustrate this:

          Example: using a 5-frame DMA ring buffer

          DMA-Queue           [ F1 ][ F2 ]
                                                           System-Space
          --------------------------------------------------------------
                                                           User-Space

                                <------------
          DCFrameQueue       [ F3 ][ F4 ][ F5 ] <-- new frames a pushed here
                               /\                   so the newest frame is always
                               |                    QUEUE.back()
                               |
                            old frames move more to the left, the leftest frame is 
                            then removed from the DCFrameQueue and enqeued into the
                            DMA-Queue, where it is filled with new frame data.

The DCGrabberThread continuously pops the oldest frame from its internal DCFrameQueue, and enques this frame into the DMA-Queue immediately. Then, it waits for the next frame that was filled by the DMA-Thread by calling dc1394_capture_deque(..,POLICY_WAIT). When this function call returns, the Thread will push the new frame into its internal DCFrameQueue, where it can be accessed by the application by calling the getCurrentImage() function.
Note: As it is strongly recommended not to create an own DCGrabberThread, but to use an instance of the DCGrabber instead, the DCGrabberThread has no public constructor.

Constructor & Destructor Documentation

icl::io::dc::DCGrabberThread::DCGrabberThread	(	dc1394camera_t *	c,
		DCDeviceOptions *	options
	)		`[private]`

private constructor )can only be called by icl::DCGrabber

icl::io::dc::DCGrabberThread::~DCGrabberThread ( ) [private]

Destructor.

Member Function Documentation

void icl::io::dc::DCGrabberThread::getCurrentImage	(	core::ImgBase **	ppoDst,
		core::ImgBase **	ppoDstTmp,
		bool &	desiredParamsFullfilled,
		const utils::Size &	desiredSizeHint,
		core::format	desiredFormatHint,
		core::depth	desiredDepthHint,
		dc1394color_filter_t	bayerLayout,
		dc1394bayer_method_t	bayerMethod = `DC1394_BAYER_METHOD_BILINEAR`
	)		`[private]`

private image access function

complex function to get the next image The function gets all desired params from the top level grabber, which it should fullfill. But in some cases it's not possible to satisfy all desired params constraints. In this case, this function will use the second given core::ImgBase** (ppoDstTmp) as destination image and it will set the boolean reference named desiredParamsFullfilled to false. The parent grabber can check this variable, to decide whether to use the original destination pointer (ppoDst) or to use the ppoDstTmp pointer temporarily and convert is into ppoDst by itself, using the desired params for ppoDst. TODO: some more text here !

void icl::io::dc::DCGrabberThread::getCurrentImage	(	core::ImgBase **	ppoDst,
		dc1394color_filter_t	bayerLayout,
		dc1394bayer_method_t	bayerMethod = `DC1394_BAYER_METHOD_BILINEAR`
	)		`[private]`