PVideoInputDevice Class Reference

This class defines a video input device. More...

#include <videoio.h>

Inheritance diagram for PVideoInputDevice:

List of all members.

Public Member Functions
	~PVideoInputDevice ()
	Close the video input device on destruction.
virtual bool	GetDeviceCapabilities (Capabilities *capabilities) const
	Retrieve a list of Device Capabilities.
virtual PVideoInputControl *	GetVideoInputControls ()
	Get the devices video Input controls By Default return NULL;.
virtual PBoolean	Open (const PString &deviceName, PBoolean startImmediate=true)=0
	Open the device given the device name.
virtual PBoolean	Close ()
	Close the device.
virtual PBoolean	CanCaptureVideo () const
	Is the device a camera, and obtain video.
virtual PBoolean	IsCapturing ()=0
	Determine if the video device I/O capture is in progress.
virtual PBoolean	GetFrame (PBYTEArray &frame)
	Grab a frame.
virtual PBoolean	GetFrameData (BYTE *buffer, PINDEX *bytesReturned, unsigned int &flags)
	Grab a frame, after a delay as specified by the frame rate.
virtual PBoolean	GetFrameData (BYTE *buffer, PINDEX *bytesReturned=NULL)=0
virtual PBoolean	GetFrameDataNoDelay (BYTE *buffer, PINDEX *bytesReturned, unsigned int &flags)
	Grab a frame.
virtual PBoolean	GetFrameDataNoDelay (BYTE *buffer, PINDEX *bytesReturned=NULL)=0
virtual bool	FlowControl (const void *flowData)
	Pass data to the inputdevice for flowControl determination.
virtual bool	SetCaptureMode (unsigned mode)
	Set the capture modes for implementations that support them.
virtual int	GetCaptureMode () const
	Returns the current capture mode.
Static Public Member Functions
static PStringArray	GetDriverNames (PPluginManager *pluginMgr=NULL)
	Get the list of available video input drivers (plug-ins).
static PStringArray	GetDriversDeviceNames (const PString &driverName, PPluginManager *pluginMgr=NULL)
	Get video input devices that correspond to the specified driver name.
static PVideoInputDevice *	CreateDevice (const PString &driverName, PPluginManager *pluginMgr=NULL)
	Create the video input device that corresponds to the specified driver name.
static PVideoInputDevice *	CreateDeviceByName (const PString &deviceName, const PString &driverName=PString::Empty(), PPluginManager *pluginMgr=NULL)
static PVideoInputDevice *	CreateOpenedDevice (const PString &driverName, const PString &deviceName, PBoolean startImmediate=true, PPluginManager *pluginMgr=NULL)
	Create an opened video input device that corresponds to the specified names.
static PVideoInputDevice *	CreateOpenedDevice (const OpenArgs &args, PBoolean startImmediate=true)
	Create an opened video output device that corresponds to the specified arguments.
static PBoolean	GetDeviceCapabilities (const PString &deviceName, Capabilities *capabilities, PPluginManager *pluginMgr=NULL)
	Retrieve a list of Device Capabilities for particular device.
static PBoolean	GetDeviceCapabilities (const PString &deviceName, const PString &driverName, Capabilities *caps, PPluginManager *pluginMgr=NULL)
	Retrieve a list of Device Capabilities for a particular driver.
Classes
struct	Capabilities

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Detailed Description

This class defines a video input device.

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Constructor & Destructor Documentation

PVideoInputDevice::~PVideoInputDevice

(

)

[inline]

Close the video input device on destruction.

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Member Function Documentation

virtual PBoolean PVideoInputDevice::CanCaptureVideo

(

)

const [virtual]

Is the device a camera, and obtain video.

Implements PVideoDevice.

virtual PBoolean PVideoInputDevice::Close

(

)

[inline, virtual]

Close the device.

Implements PVideoDevice.

Reimplemented in PVideoInput1394DcDevice.

static PVideoInputDevice* PVideoInputDevice::CreateDevice	(	const PString &	driverName,
		PPluginManager *	pluginMgr = NULL
	)			[static]

Create the video input device that corresponds to the specified driver name.

Parameters:

driverName	Name of driver
pluginMgr	Plug in manager, use default if NULL

static PVideoInputDevice* PVideoInputDevice::CreateDeviceByName	(	const PString &	deviceName,
		const PString &	driverName = PString::Empty(),
		PPluginManager *	pluginMgr = NULL
	)			[static]

Parameters:

deviceName	Name of device
driverName	Name of driver (if any)
pluginMgr	Plug in manager, use default if NULL

static PVideoInputDevice* PVideoInputDevice::CreateOpenedDevice	(	const OpenArgs &	args,
		PBoolean	startImmediate = true
	)			[static]

Create an opened video output device that corresponds to the specified arguments.

Parameters:

args	Parameters to set on opened device
startImmediate	Immediately start display

static PVideoInputDevice* PVideoInputDevice::CreateOpenedDevice	(	const PString &	driverName,
		const PString &	deviceName,
		PBoolean	startImmediate = true,
		PPluginManager *	pluginMgr = NULL
	)			[static]

Create an opened video input device that corresponds to the specified names.

If the driverName parameter is an empty string or "*" then CreateDeviceByName is used with the deviceName parameter which is assumed to be a value returned from GetDriversDeviceNames().

Parameters:

driverName	Name of driver
deviceName	Name of device
startImmediate	Immediately start grabbing
pluginMgr	Plug in manager, use default if NULL

virtual bool PVideoInputDevice::FlowControl

(

const void *

flowData

)

[virtual]

Pass data to the inputdevice for flowControl determination.

virtual int PVideoInputDevice::GetCaptureMode

(

)

const [virtual]

Returns the current capture mode.

See SetCaptureMode() for more details. A return value of -1 indicates an error or the mode is not supported.

static PBoolean PVideoInputDevice::GetDeviceCapabilities	(	const PString &	deviceName,
		const PString &	driverName,
		Capabilities *	caps,
		PPluginManager *	pluginMgr = NULL
	)			[static]

Retrieve a list of Device Capabilities for a particular driver.

Parameters:

deviceName	Name of device
driverName	Device Driver
caps	List of supported capabilities
pluginMgr	Plug in manager, use default if NULL

static PBoolean PVideoInputDevice::GetDeviceCapabilities	(	const PString &	deviceName,
		Capabilities *	capabilities,
		PPluginManager *	pluginMgr = NULL
	)			[static]

Retrieve a list of Device Capabilities for particular device.

Parameters:

deviceName	Name of device
capabilities	List of supported capabilities
pluginMgr	Plug in manager, use default if NULL

virtual bool PVideoInputDevice::GetDeviceCapabilities

(

Capabilities *

capabilities

)

const [inline, virtual]

Retrieve a list of Device Capabilities.

Parameters:

capabilities

List of supported capabilities

static PStringArray PVideoInputDevice::GetDriverNames

(

PPluginManager *

pluginMgr = NULL

)

[static]

Get the list of available video input drivers (plug-ins).

Parameters:

pluginMgr

Plug in manager, use default if NULL

static PStringArray PVideoInputDevice::GetDriversDeviceNames	(	const PString &	driverName,
		PPluginManager *	pluginMgr = NULL
	)			[static]

Get video input devices that correspond to the specified driver name.

If driverName is an empty string or the value "*" then this will return a list of unique device names across all of the available drivers. If two drivers have identical names for devices, then the string returned will be of the form driver+'\t'+device.

Parameters:

driverName	Name of driver
pluginMgr	Plug in manager, use default if NULL

virtual PBoolean PVideoInputDevice::GetFrame

(

PBYTEArray &

frame

)

[virtual]

Grab a frame.

virtual PBoolean PVideoInputDevice::GetFrameData	(	BYTE *	buffer,
		PINDEX *	bytesReturned = NULL
	)			[pure virtual]

Parameters:

buffer	Buffer to receive frame
bytesReturned	Optional bytes returned.

Implemented in PVideoInput1394DcDevice.

virtual PBoolean PVideoInputDevice::GetFrameData	(	BYTE *	buffer,
		PINDEX *	bytesReturned,
		unsigned int &	flags
	)			[virtual]

Grab a frame, after a delay as specified by the frame rate.

Parameters:

buffer	Buffer to receive frame
bytesReturned	Optional bytes returned.
flags	optional flags returned

virtual PBoolean PVideoInputDevice::GetFrameDataNoDelay	(	BYTE *	buffer,
		PINDEX *	bytesReturned = NULL
	)			[pure virtual]

Parameters:

buffer	Buffer to receive frame
bytesReturned	Optional bytes returned.

Implemented in PVideoInput1394DcDevice.

virtual PBoolean PVideoInputDevice::GetFrameDataNoDelay	(	BYTE *	buffer,
		PINDEX *	bytesReturned,
		unsigned int &	flags
	)			[virtual]

Grab a frame.

Do not delay according to the current frame rate parameter.

Parameters:

buffer	Buffer to receive frame
bytesReturned	Optional bytes returned.
flags	optional flags returned

virtual PVideoInputControl* PVideoInputDevice::GetVideoInputControls

(

)

[virtual]

Get the devices video Input controls By Default return NULL;.

virtual PBoolean PVideoInputDevice::IsCapturing

(

)

[pure virtual]

Determine if the video device I/O capture is in progress.

Implemented in PVideoInput1394DcDevice.

virtual PBoolean PVideoInputDevice::Open	(	const PString &	deviceName,
		PBoolean	startImmediate = true
	)			[pure virtual]

Open the device given the device name.

Parameters:

deviceName	Device name to open
startImmediate	Immediately start device

Implements PVideoDevice.

Implemented in PVideoInput1394DcDevice.

virtual bool PVideoInputDevice::SetCaptureMode

(

unsigned

mode

)

[virtual]

Set the capture modes for implementations that support them.

For example with Video For Windows, this is used to select picture (0) or video (1) modes.

In picture-mode the implementation requests a single frame from the connected camera device. The camera device then does nothing until the frame has been processed and the next is requested.

In video-mode the camera continuously sends new frames.

The default implementation does nothing but returns PFalse.

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The documentation for this class was generated from the following file:

• videoio.h

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