Grabber

This is the main class of the IC Imaging Control Class Library. It provides the basic functionality to control the flow of image buffers in an image stream from the source (a video capture device) to the sink (a collection of image buffers or a media file). The display of a live image can be toggled on and off. The idea behind this class is to provide the functionality of a standard frame grabber to users of WDM streaming devices.

Using this class, programmers can:

select a video source
change parameters of a video source
display a live image
prepare, start and stop the image stream from the device to the sink (image buffers / media file)
specify the sink (image buffers / media file)
apply one or more frame filters to the image stream
apply overlays at 3 different locations to the image stream

Information

Header File: tisudshl.h
Namespace: DShowLib

Methods

	Method		Description


	Grabber		Constructs a new Grabber object.

	addListener		This method registers a callback handler object for the specified events.

	closeDev		Closes the currently active video capture device.

	execI2COperation		Performs a read/write operation on the I²C bus of the currently used video capture device.

	getAcqSizeMaxX		Returns the width in pixels of the currently selected video format.

	getAcqSizeMaxY		Returns the height in pixels of the currently selected video format.

	getAvailableFPS		Returns the available frame rates.

	getAvailableInputChannels		Returns a list of input channels supported by the current device.

	getAvailableVCDProperties		Returns a collection of the IVCDPropertyItems of the currently opened device.

	getAvailableVideoCaptureDevices		Returns a list of all currently available video capture devices.

	getAvailableVideoFormatDescs		Returns a list of VideoFormatDesc objects describing all video formats supported by the current video capture device according to the current video norm.

	getAvailableVideoFormats		Returns a list of all video formats supported by the current video capture device according to the current video norm.

	getAvailableVideoNorms		Returns a list of all video norms supported by the current video capture device.

	getCountOfFramesDropped		Returns the number of frames that were dropped by the video capture device.

	getCountOfFramesNotDropped		Returns the number of frames that were delivered by the device.

	getCurReferenceTime		Retrieves the current reference time.

	getCurrentActualFPS		[Deprecated] Retrieves the actual frame rate achieved by the device.

	getCurrentMaxAvailableFPS		[Deprecated] Returns the current maximal frames per second (FPS) that the device can achieve on the bus.

	getDeBayerTransform		Returns a pointer to a DeBayerTransform object. If a BY8 Bayer video format is selected, the image data will be debayered automatically. The DeBayerTransform class allows the debayering to be checked.

	getDefaultWindowPosition		This method returns the current value of the grabber's default window position flag.

	getDev		Returns the currently active video capture device.

	getDeviceFrameFilters		Returns the list of frame filters that are currently set behind the device.

	getDisplayFrameFilters		Returns the list of frame filters that are currently set in front of the display.

	getDriverFrameDropInformation		Retrieves frame drop information from the driver if supported by it.

	getExternalTrigger		Returns true, if the external trigger is enabled.

	getFPS		Returns the frame rate currently set.

	getFlipH		This method returns whether horizontal flipping is enabled.

	getFlipV		This method returns whether vertical flipping is enabled.

	getGraphStartReferenceTime		This method retrieves the reference time at which the image stream (the filter graph) was started.

	getHWND		This method returns a handle to the window, which is used to display the live image.

	getInputChannel		Returns the currently active input channel. This method will fail, if there is no video capture device open.

	getLastError		Returns information about an error that occurred, during the last library-method call.

	getOverlay		This method returns a pointer to an instance of the OverlayBitmap object. The OverlayBitmap is used to draw text and graphics on the video stream.

	getOverlayBitmapPathPosition		Returns the current position of OverlayBitmap objects in the graph.

	getPauseLive		Returns whether pause mode is enabled.

	getSignalDetected		Returns whether a signal was detected by the device.

	getSinkTypePtr		Returns a pointer to the currently selected sink.

	getVCDPropertyElement		Retrieves the specified IVCDPropertyElement.

	getVCDPropertyInterface		Retrieves the specified IVCDPropertyInterface.

	getVCDPropertyItem		Retrieves the specified IVCDPropertyItem.

	getVideoDataDimension		Returns the actual dimension of the image data which is passed to the display. This may be different from the video format of the currently active video capture device, if you have used setDeviceFrameFilters or setDisplayFrameFilters to insert frame filters in the image stream behind the device or in front of the display. If IFrameFilter objects are used by the FrameHandlerSink, the dimension of the MemBufferCollection may be different from the video data dimension as well.

	getVideoFormat		This method returns the currently selected video format or an invalid object, if no video format is set (ie. the device is not open).

	getVideoNorm		This method returns the currently selected video norm or an invalid object, if no video norm is selected.

	getWindowPosition		This method retrieves the current position and size of the grabber's live video window.

	hasCountOfFrames		Returns whether the device supports retrieving the current dropped frames counter.

	hasExternalTrigger		Returns true, if the current device has an external trigger.

	hasFPSList		Checks whether the currently selected video capture device supports different frame rates that can be set by the user.

	hasI2CInterface		Checks whether the currently opened video capture device supports access to its on-board I²C bus.

	hasInputChannels		This method checks whether the currently opened video capture device supports input channels.

	hasSignalDetected		Checks whether a device can be queried if it has a video stream. (Some analog to digital video converters have this property).

	hasVideoNorms		Checks whether the current video capture device supports video norms.

	isCountOfFramesDroppedAvailable		[Deprecated] Returns whether the device supports retrieving the current dropped frames counter.

	isDevOpen		Checks whether a video capture device is opened.

	isDevValid		Checks whether the video capture device associated with this object still exists. A video capture device may become invalid at any time (e.g. if the device has been unplugged).

	isFlipHAvailable		This method returns whether horizontal flipping is available.

	isFlipVAvailable		This method returns whether vertical flipping is available.

	isFrameRateListAvailable		[Deprecated] Checks whether the currently selected video capture device supports different frame rates that can be set by the user.

	isInputChannelAvailableWithCurDev		This method checks whether the currently active video capture device supports input channels.

	isListenerRegistered		This method checks whether the specified callback handler is registered for the specified events.

	isLive		Checks whether the current video capture device is in live mode.

	isLivePrepared		Returns whether the image stream is in 'prepared' state.

	isSignalDetectedAvailable		[Deprecated] Checks whether a device can be queried for a list of available video stream.

	isVideoNormAvailableWithCurDev		[Deprecated] Checks whether the current video capture device supports the selection of the video norm.

	loadDeviceState		Restores grabber settings that were saved by saveDeviceState.

	loadDeviceStateFromFile		Restores the device settings from a file that was previously saved by saveDeviceStateToFile.

	openDev		Opens a video capture device for grabbing.

	openDevByDisplayName		Opens a device by its display name.

	openDevByUniqueName		Opens a device by its unique name.

	prepareLive		Tries to setup the image stream by connecting the device with the display and the sink and inserting frame filters and overlays.

	removeListener		This method unregisters a callback handler object for the specified events.

	saveDeviceState		Saves the state of the opened device. A saved state can be restored using loadDeviceState.

	saveDeviceStateToFile		Saves the state of the currently opened device to a file. The grabber state can be restored using loadDeviceStateFromFile.

	setDefaultWindowPosition		Enables or disables the default window size lock of the video window.

	setDeviceFrameFilters		Inserts a list of frame filters in the device path of the image stream. If an overlay is present in the device path, the filter list is inserted in front it. This means that the filter list is located between the device and the overlay.

	setDisplayFrameFilters		Inserts a list of frame filters in the display path of the image stream. If an overlay is present in the display path, the filter list is inserted in front of it. This means that the overlay is located between the filter list and the display. If there is no overlay in the display path, the filter list is inserted in front of the the display.

	setExternalTrigger		Enables/disables the external trigger.

	setFPS		Sets the frame rate of the device.

	setFlipH		Specifies whether all frames of an image stream should be flipped horizontally.

	setFlipV		Specifies whether all frames of an image stream will be flipped vertically.

	setHWND		Sets the handle to the window in which the live image will be displayed.

	setInputChannel		Sets the input channel of the currently active video capture device.

	setOverlayBitmapPathPosition		Sets the positions of OverlayBitmap objects in the graph.

	setPauseLive		Pauses the live mode.

	setSinkType		Sets the format of the sink. A sink specifies the output target of an image stream. A sink may only be set, if the image stream is in neither live mode, nor prepared mode.

	setVideoFormat		This method sets the video format to be used by the currently active video capture device.

	setVideoNorm		This method sets the video of the currently active video capture device. A list of available video norms may be retrieved by calling Grabber::getAvailableVideoNorms.

	setWindowPosition		Sets the position of the grabber's live video window.

	setWindowSize		Sets the size of the video window.

	showDevicePage		Shows a device settings page.

	showVCDPropertyPage		Shows the property page for this device. With the property page, the user can adjust property settings like brightness.

	startLive		Puts the grabber in live mode.

	stopLive		Stops the grabber

	suspendLive		Suspends an image stream and puts it into prepared state.

Enumerations

	Enumeration		Description


	tCameraPropertyEnum		tCameraPropertyEnum enumerates the properties of a video camera.

	tVideoPropertyEnum		tVideoPropertyEnum specifies video property types. This enumeration comes directly from DirectX 8.

Type Definitions

	Type		Description


	tFPSList		An array of double values that describe the number of frames per second.

	tFPSListPtr		A pointer to a tFPSList.

	tInChnList		A list of AnalogChannelItems.

	tInChnListPtr		A pointer to a list of tVideoFormatItems.

	tInputChannelItem		A AnalogChannelItem.

	tMemBufferCollectionPtr		A pointer to a MemBufferCollection.

	tMemBufferPtr		A pointer to a MemBuffer.

	tVidCapDevList		A list of tVideoCaptureDeviceItems.

	tVidCapDevListPtr		A pointer to a list of tVideoCaptureDeviceItems.

	tVidFmtDescList		A tVidFmtDescList is a std::vector of smart pointers to VideoFormatDesc objects.

	tVidFmtDescListPtr		A tVidFmtDescListPtr is smart pointer to a tVidFmtDescList. objects.

	tVidFmtDescPtr		A tVidFmtDescPtr is a smart pointer to a VideoFormatDesc object.

	tVidFmtList		A list of tVideoFormatItems.

	tVidFmtListPtr		A pointer to a list of tVideoFormatItems.

	tVidNrmList		A list of tVideoNormItems.

	tVidNrmListPtr		A pointer to a list of tVideoNormItems.

	tVideoCaptureDeviceItem		A VideoCaptureDeviceItem.

	tVideoFormatItem		A VideoFormatItem.

	tVideoNormItem		A VideoNormItem.

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