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Video4LinuxSource Class Reference

A class which implements the ImageSource interface as a source of Images supplied from a Video4Linux compatible device such as webcams and tv cards. More...

#include <Video4LinuxSource.h>

Inheritance diagram for Video4LinuxSource::

List of all members.

Public Methods
	Video4LinuxSource (char *device, bool sup_memory_map)
	Initialise a Video4Linux source. More...
virtual	~Video4LinuxSource ()
	Close the device and unmap any mapped memory or free up memory if necessary.
virtual ImageSource&	operator>> (ImageRGB &)
	Extract a colour image into the images data buffer.
virtual ImageSource&	operator>> (ImageGrey &)
	Extract a greyscale image into the images brightness buffer.
virtual ImageSource&	operator>> (Image &)
	Extract an image dependant on the default type.
void	set_size (unsigned int, unsigned int)
	Set the size of source Images. More...
void	set_framerate (unsigned int)
	Set the rate of Image acquistion. More...
void	set_palette (int)
	Set the palette of the acquired Images. More...
void	set_channel (int)
	Set the channel to use for image acquisition. More...
virtual void	get_size (unsigned int &, unsigned int &)
	Get the size of the source Images.
void	get_framerate (unsigned int &)
	Get the rate of Image acquisition.
void	get_palette (int &)
	Get the palette used by acquired Images.
Protected Methods
int	set_capability (video_capability &)
int	set_frameBuffer (video_buffer &)
	ioctl wrapper for VIDIOCSFBUF.
int	set_captureWindows (video_window &)
	ioctl wrapper for VIDIOCSWIN.
int	set_videoSource (int)
	ioctl wrapper for VIDIOCSCHAN.
int	set_imageProperties (video_picture &)
	ioctl wrapper for VIDIOCSPICT.
int	set_tuning (video_tuner &)
	ioctl wrapper for VIDIOCSTUNER.
int	set_memoryBuffer (video_mbuf &)
int	get_capability (video_capability &)
	ioctl wrapper for VIDIOCGCAP.
int	get_frameBuffer (video_buffer &)
	ioctl wrapper for VIDIOCGFBUF.
int	get_captureWindows (video_window &)
	ioctl wrapper for VIDIOCGWIN.
int	get_videoSource (video_channel &)
	ioctl wrapper for VIDIOCGCHAN.
int	get_imageProperties (video_picture &)
	ioctl wrapper for VIDIOCGPICT.
int	get_tuning (video_tuner &)
	ioctl wrapper for VIDIOCGTUNER.
int	get_memoryBuffer (video_mbuf &)
	ioctl wrapper for VIDIOCGMBUF.
void	print_capability (video_capability &)
void	print_frameBuffer (video_buffer &)
void	print_captureWindows (video_window &)
void	print_videoSource (video_channel &)
void	print_imageProperties (video_picture &)
void	print_tuning (video_tuner &)
void	print_memoryBuffer (video_mbuf &)
Protected Attributes
int	fd
	device file handle.
unsigned char*	buff
	temporary buffer.
unsigned int	buffsize
	size of temporary buffer.
int	currentBuffer
	number of current buffer.
int	numBuffers
	total number of buffers.
unsigned int	width
	width of source image.
unsigned int	height
	height of source image.
unsigned int	size
	total size of source image.
video_mbuf	mbuf
	memory buffer structure.
video_mmap	vmmap
	memory map structure.
int	palette
	palette to use for the device.
bool	capture
	true if capture to memory is possible for this device. More...
void (*	convert_rgb )(int width, int height, void *, void *)
	conversion method for colour Images.
void (*	convert_grey )(int width, int height, void *, void *)
	conversion method for greyscale Images.

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Detailed Description

A class which implements the ImageSource interface as a source of Images supplied from a Video4Linux compatible device such as webcams and tv cards.

Bug:

Memory mapping is not yet functional.

Todo:

Needs to be expanded to add more of the Video4Linux API so that more devices can be supported 'out of the box'.

Definition at line 31 of file Video4LinuxSource.h.

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Constructor & Destructor Documentation

Video4LinuxSource::Video4LinuxSource ( char * device, bool sup_memory_map )

Initialise a Video4Linux source. Parameters: device   The Video4Linux compatible device. Definition at line 38 of file Video4LinuxSource.cpp.

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Member Function Documentation

void Video4LinuxSource::set_channel ( int channel )

Set the channel to use for image acquisition. Parameters: channel   The channel to use. Definition at line 250 of file Video4LinuxSource.cpp.

void Video4LinuxSource::set_framerate ( unsigned int fps )

Set the rate of Image acquistion. Note: Although the device is issued with the instruction to change framerate it may not be changed in the device itself. Sometimes this is necessary so that incorect values cannot be set. Parameters: fps   The framerate to use. Definition at line 183 of file Video4LinuxSource.cpp.

void Video4LinuxSource::set_palette ( int pal )

Set the palette of the acquired Images. Note: Although the device is issued with the instruction to change palette it may not be changed in the device itself. Normally this will be because the selected palette is not supported. Parameters: pal   The palette to use. Definition at line 208 of file Video4LinuxSource.cpp.

void Video4LinuxSource::set_size ( unsigned int w, unsigned int h )

Set the size of source Images. Note: Although the device is issued with the instruction to change size it may not be changed in the device itself. Sometimes this is necessary so that incorect values cannot be set. Parameters: w   The width of the Image. h   The height of the Image. Definition at line 127 of file Video4LinuxSource.cpp.

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Member Data Documentation

bool Video4LinuxSource::capture [protected]

true if capture to memory is possible for this device. This is always false though see constructor in Video4Linux.cpp Definition at line 65 of file Video4LinuxSource.h.

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

• Video4LinuxSource.h
• Video4LinuxSource.cpp

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