#include <vpV4l2Grabber.h>

Inheritance diagram for vpV4l2Grabber:

Public Types
enum	vpV4l2FramerateType { framerate_50fps , framerate_25fps }
enum	vpV4l2FrameFormatType { V4L2_FRAME_FORMAT , V4L2_IMAGE_FORMAT }
enum	vpV4l2PixelFormatType { V4L2_GREY_FORMAT , V4L2_RGB24_FORMAT , V4L2_RGB32_FORMAT , V4L2_BGR24_FORMAT , V4L2_YUYV_FORMAT , V4L2_MAX_FORMAT }

Public Member Functions
	vpV4l2Grabber ()
	vpV4l2Grabber (bool verbose)
	vpV4l2Grabber (unsigned input, unsigned scale=vpV4l2Grabber::DEFAULT_SCALE)
	vpV4l2Grabber (vpImage< unsigned char > &I, unsigned input, unsigned scale=vpV4l2Grabber::DEFAULT_SCALE)
	vpV4l2Grabber (vpImage< vpRGBa > &I, unsigned input, unsigned scale=vpV4l2Grabber::DEFAULT_SCALE)
virtual	~vpV4l2Grabber ()
void	open (vpImage< unsigned char > &I)
void	open (vpImage< vpRGBa > &I)
void	acquire (vpImage< unsigned char > &I)
void	acquire (vpImage< unsigned char > &I, const vpRect &roi)
void	acquire (vpImage< unsigned char > &I, struct timeval &timestamp, const vpRect &roi=vpRect())
void	acquire (vpImage< vpRGBa > &I)
void	acquire (vpImage< vpRGBa > &I, const vpRect &roi)
void	acquire (vpImage< vpRGBa > &I, struct timeval &timestamp, const vpRect &roi=vpRect())
bool	getField ()
vpV4l2FramerateType	getFramerate ()
vpV4l2PixelFormatType	getPixelFormat ()
vpV4l2Grabber &	operator>> (vpImage< unsigned char > &I)
vpV4l2Grabber &	operator>> (vpImage< vpRGBa > &I)
void	setVerboseMode (bool verbose)
void	setFramerate (vpV4l2FramerateType framerate)
void	setInput (unsigned input=vpV4l2Grabber::DEFAULT_INPUT)
void	setWidth (unsigned w)
void	setHeight (unsigned h)
void	setScale (unsigned scale=vpV4l2Grabber::DEFAULT_SCALE)
void	setNBuffers (unsigned nbuffers)
void	setDevice (const std::string &devname)
void	setFrameFormat (vpV4l2FrameFormatType frameformat)
void	open ()
void	getCapabilities ()
void	startStreaming ()
void	stopStreaming ()
unsigned char *	waiton (__u32 &index, struct timeval &timestamp)
int	queueBuffer ()
void	queueAll ()
void	printBufInfo (struct v4l2_buffer buf)
Inherited functionalities from vpFramegrabber
unsigned int	getHeight () const
unsigned int	getWidth () const
virtual void	close ()=0

Public Attributes
int	fd
std::string	device
struct v4l2_capability	cap
struct v4l2_streamparm	streamparm
struct v4l2_input *	inp
struct v4l2_standard *	std
struct v4l2_fmtdesc *	fmt
struct v4l2_queryctrl *	ctl
struct v4l2_format	fmt_v4l2
struct ng_video_fmt	fmt_me
struct v4l2_requestbuffers	reqbufs
struct v4l2_buffer *	buf_v4l2
struct ng_video_buf *	buf_me
unsigned int	queue
unsigned int	waiton_cpt
__u32	index_buffer
bool	m_verbose
unsigned	m_nbuffers
unsigned int	field
bool	streaming
unsigned	m_input
vpV4l2FramerateType	m_framerate
vpV4l2FrameFormatType	m_frameformat
vpV4l2PixelFormatType	m_pixelformat
bool	init

Static Public Attributes
static const unsigned int	DEFAULT_INPUT = 2
static const unsigned int	DEFAULT_SCALE = 2
static const __u32	MAX_INPUTS = 16
static const __u32	MAX_NORM = 16
static const __u32	MAX_FORMAT = 32
static const unsigned int	MAX_CTRL = 32
static const unsigned int	MAX_BUFFERS = 32
static const unsigned int	FRAME_SIZE = 288

Protected Attributes
unsigned int	height
unsigned int	width

Detailed Description

Class that is a wrapper over the Video4Linux2 (V4L2) driver.

Thus to be enabled, this class needs the optional V4L2 3rd party. Installation instruction are provided here https://visp.inria.fr/3rd_v4l2.

Information about Video4Linux can be found on http://linuxtv.org/v4lwiki/index.php/Main_Page

This class was tested with a Pinnacle PCTV Studio/Rave board but also with the following webcams (Logitech QuickCam Vision Pro 9000, Logitech QuickCam Orbit AF, Logitech QuickCam IM (V-USB39), Dell latitude E6400 internal webcam).

If the grabbing fail with a webcam, it means probably that you don't have the read/write permission on the /dev/video%d device. You can set the right permissions by "sudo chmod a+rw /dev/video*".

If the grabbing fails when the camera is attached to a bttv PCI card, it means potentially that you have not configured the linux bttv kernel module according to your board.

For that, depending on your linux distribution check the card id in

/usr/share/doc/kernel-doc-2.4.20/video4linux/bttv/CARDLIST
or /usr/share/doc/kernel-doc-2.6.20/Documentation/video4linux/CARDLIST.bttv

For example, the card id of a Pinnacle PCTV Studio/Rave board is 39. Once this id is determined, you have to set the bttv driver with, by adding

  options bttv card=39

in one of theses files :

/etc/modules.conf
or /etc/modprobe.conf

This first example available in tutorial-grabber-v4l2.cpp shows how to grab and display images from an usb camera.

#include <visp3/core/vpImage.h>
#include <visp3/gui/vpDisplayOpenCV.h>
#include <visp3/gui/vpDisplayX.h>
#include <visp3/io/vpImageStorageWorker.h>
#include <visp3/sensor/vpV4l2Grabber.h>
 
#define USE_COLOR // Comment to acquire gray level images
 
void usage(const char *argv[], int error)
{
  std::cout << "SYNOPSIS" << std::endl
            << "  " << argv[0] << " [--device <index>]"
            << " [--scale <subsampling factor>]"
            << " [--seqname <sequence name>]"
            << " [--record <mode>]"
            << " [--no-display]"
            << " [--help] [-h]" << std::endl
            << std::endl;
  std::cout << "DESCRIPTION" << std::endl
            << "  --device <index> " << std::endl
            << "    Camera device index. Set 0 to dial with the first camera," << std::endl
            << "    and 1 to dial with the second camera attached to the computer." << std::endl
            << "    Default: 0 to consider /dev/video0 device." << std::endl
            << std::endl
            << "  --scale <subsampling factor>" << std::endl
            << "    Subsampling factor applied to the images captured by the device." << std::endl
            << "    Default: 1" << std::endl
            << std::endl
            << "  --seqname <sequence name>" << std::endl
            << "    Name of the sequence of image to create (ie: /tmp/image%04d.jpg)." << std::endl
            << "    Default: empty." << std::endl
            << std::endl
            << "  --record <mode>" << std::endl
            << "    Allowed values for mode are:" << std::endl
            << "      0: record all the captures images (continuous mode)," << std::endl
            << "      1: record only images selected by a user click (single shot mode)." << std::endl
            << "    Default mode: 0" << std::endl
            << std::endl
            << "  --no-display" << std::endl
            << "    Disable displaying captured images." << std::endl
            << "    When used and sequence name specified, record mode is internally set to 1 (continuous mode)."
            << std::endl
            << std::endl
            << "  --help, -h" << std::endl
            << "    Print this helper message." << std::endl
            << std::endl;
  std::cout << "USAGE" << std::endl
            << "  Example to visualize images:" << std::endl
            << "    " << argv[0] << std::endl
            << std::endl
            << "  Example to visualize images from a second camera:" << std::endl
            << "    " << argv[0] << " --device 1" << std::endl
            << std::endl
            << "  Examples to record a sequence:" << std::endl
            << "    " << argv[0] << " --seqname I%04d.png" << std::endl
            << "    " << argv[0] << " --seqname folder/I%04d.png --record 0" << std::endl
            << std::endl
            << "  Examples to record single shot images:\n"
            << "    " << argv[0] << " --seqname I%04d.png --record 1\n"
            << "    " << argv[0] << " --seqname folder/I%04d.png --record 1" << std::endl
            << std::endl;
 
  if (error) {
    std::cout << "Error" << std::endl
              << "  "
              << "Unsupported parameter " << argv[error] << std::endl;
  }
}
int main(int argc, const char *argv[])
{
#if defined(VISP_HAVE_V4L2) && (VISP_CXX_STANDARD >= VISP_CXX_STANDARD_11)
  try {
    int opt_device = 0;
    unsigned int opt_scale = 1; // Default value is 2 in the constructor. Turn
                                // it to 1 to avoid subsampling
    std::string opt_seqname;
    int opt_record_mode = 0;
    bool opt_display = true;
 
    for (int i = 1; i < argc; i++) {
      if (std::string(argv[i]) == "--device") {
        opt_device = std::atoi(argv[i + 1]);
        i++;
      } else if (std::string(argv[i]) == "--scale") {
        opt_scale = (unsigned int)atoi(argv[i + 1]);
        i++;
      } else if (std::string(argv[i]) == "--seqname") {
        opt_seqname = std::string(argv[i + 1]);
        i++;
      } else if (std::string(argv[i]) == "--record") {
        opt_record_mode = std::atoi(argv[i + 1]);
        i++;
      } else if (std::string(argv[i]) == "--no-display") {
        opt_display = false;
      } else if (std::string(argv[i]) == "--help" || std::string(argv[i]) == "-h") {
        usage(argv, 0);
        return EXIT_SUCCESS;
      } else {
        usage(argv, i);
        return EXIT_FAILURE;
      }
    }
 
    if ((!opt_display) && (!opt_seqname.empty())) {
      opt_record_mode = 0;
    }
    std::cout << "Use device : " << opt_device << std::endl;
    std::cout << "Recording  : " << (opt_seqname.empty() ? "disabled" : "enabled") << std::endl;
    std::cout << "Display    : " << (opt_display ? "enabled" : "disabled") << std::endl;
 
    std::string text_record_mode =
        std::string("Record mode: ") + (opt_record_mode ? std::string("single") : std::string("continuous"));
 
    if (!opt_seqname.empty()) {
      std::cout << text_record_mode << std::endl;
      std::cout << "Record name: " << opt_seqname << std::endl;
    }
 
#ifdef USE_COLOR
    vpImage<vpRGBa> I; // To acquire color images
#else
    vpImage<unsigned char> I; // To acquire gray images
#endif
 
    vpV4l2Grabber g;
    std::ostringstream device;
    device << "/dev/video" << opt_device;
    g.setDevice(device.str());
    g.setScale(opt_scale);
    g.open(I);
 
    std::cout << "Image size : " << I.getWidth() << " " << I.getHeight() << std::endl;
 
    vpDisplay *d = NULL;
    if (opt_display) {
#if !(defined(VISP_HAVE_X11) || defined(VISP_HAVE_OPENCV))
      std::cout << "No image viewer is available..." << std::endl;
      opt_display = false;
#endif
    }
    if (opt_display) {
#ifdef VISP_HAVE_X11
      d = new vpDisplayX(I);
#elif defined(HAVE_OPENCV_HIGHGUI)
      d = new vpDisplayOpenCV(I);
#endif
    }
 
#ifdef USE_COLOR
    vpImageQueue<vpRGBa> image_queue(opt_seqname, opt_record_mode);
    vpImageStorageWorker<vpRGBa> image_storage_worker(std::ref(image_queue));
    std::thread image_storage_thread(&vpImageStorageWorker<vpRGBa>::run, &image_storage_worker);
#else
    vpImageQueue<unsigned char> image_queue(opt_seqname, opt_record_mode);
    vpImageStorageWorker<unsigned char> image_storage_worker(std::ref(image_queue));
    std::thread image_storage_thread(&vpImageStorageWorker<unsigned char>::run, &image_storage_worker);
#endif
 
    bool quit = false;
    while (!quit) {
      double t = vpTime::measureTimeMs();
      g.acquire(I);
 
      vpDisplay::display(I);
 
      quit = image_queue.record(I);
 
      std::stringstream ss;
      ss << "Acquisition time: " << std::setprecision(3) << vpTime::measureTimeMs() - t << " ms";
      vpDisplay::displayText(I, I.getHeight() - 20, 10, ss.str(), vpColor::red);
      vpDisplay::flush(I);
    }
    image_queue.cancel();
    image_storage_thread.join();
 
    if (d) {
      delete d;
    }
  } catch (const vpException &e) {
    std::cout << "Catch an exception: " << e << std::endl;
  }
#else
  (void)argc;
  (void)argv;
#ifndef VISP_HAVE_V4L2
  std::cout << "Install Video 4 Linux 2 (v4l2), configure and build ViSP again to use this example" << std::endl;
#endif
#if (VISP_CXX_STANDARD < VISP_CXX_STANDARD_11)
  std::cout << "This tutorial should be built with c++11 support" << std::endl;
#endif
#endif
}

This other example shows how to use this grabber with an analogic camera attached to a bttv PCI card.

#include <visp3/io/vpImageIo.h>
#include <visp3/sensor/vpV4l2Grabber.h>
 
int main()
{
#if defined(VISP_HAVE_V4L2)
  vpImage<unsigned char> I;
  vpV4l2Grabber g;
  g.setInput(2);    // Input 2 on the board
  g.setFramerate(vpV4l2Grabber::framerate_25fps); //  25 fps
  g.setWidth(768);  // Acquired images are 768 width
  g.setHeight(576); // Acquired images are 576 height
  g.setNBuffers(3); // 3 ring buffers to ensure real-time acquisition
  g.open(I);        // Open the grabber
 
  g.acquire(I);     // Acquire a 768x576 grey image
  vpImageIo::write(I, "image.pgm"); // Save the image on the disk
#endif
}

Author: Fabien Spindler (Fabie.nosp@m.n.Sp.nosp@m.indle.nosp@m.r@ir.nosp@m.isa.f.nosp@m.r), Irisa / Inria Rennes

See also: vpFrameGrabber

Definition at line 132 of file vpV4l2Grabber.h.

Member Enumeration Documentation

◆ vpV4l2FrameFormatType

enum vpV4l2Grabber::vpV4l2FrameFormatType

Frame format type for capture.

Enumerator
V4L2_FRAME_FORMAT	a field only
V4L2_IMAGE_FORMAT	an interlaced image

Definition at line 155 of file vpV4l2Grabber.h.

◆ vpV4l2FramerateType

enum vpV4l2Grabber::vpV4l2FramerateType

Frame rate type for capture.

Enumerator
framerate_50fps	50 frames per second
framerate_25fps	25 frames per second

Definition at line 147 of file vpV4l2Grabber.h.

◆ vpV4l2PixelFormatType

enum vpV4l2Grabber::vpV4l2PixelFormatType

Pixel format type for capture.

Enumerator
V4L2_GREY_FORMAT	8 Greyscale
V4L2_RGB24_FORMAT	24 RGB-8-8-8
V4L2_RGB32_FORMAT	32 RGB-8-8-8-8
V4L2_BGR24_FORMAT	24 BGR-8-8-8
V4L2_YUYV_FORMAT	16 YUYV 4:2:2
V4L2_MAX_FORMAT

Examples: grabV4l2.cpp.

Definition at line 163 of file vpV4l2Grabber.h.

Constructor & Destructor Documentation

◆ vpV4l2Grabber() [1/5]

vpV4l2Grabber::vpV4l2Grabber ( )

Default constructor.

Setup the Video For Linux Two (V4L2) driver in streaming mode.

Default settings are:

Device name: /dev/video0: To change it use setDevice()
Number of ring buffers: 3. To change this value use setNBuffers(). For non real-time applications the number of buffers should be set to 1. For real-time applications to reach 25 fps or 50 fps a good compromise is to set the number of buffers to 3.
Framerate acquisition: 25 fps. Use setFramerate() to set 25 fps or 50 fps. These framerates are reachable only if enought buffers are set.
Input board: vpV4l2Grabber::DEFAULT_INPUT. Video input port. Use setInput() to change it.

Image size acquisition: vpV4l2Grabber::DEFAULT_SCALE. Use either setScale() or setWidth() and setHeight() to change it.

\code
vpImage<unsigned char> I; // Grey level image

vpV4l2Grabber g;
g.setInput(2);    // Input 2 on the board
g.setWidth(768);  // Acquired images are 768 width
g.setHeight(576); // Acquired images are 576 height
g.setNBuffers(3); // 3 ring buffers to ensure real-time acquisition
g.open(I);        // Open the grabber

g.acquire(I);     // Acquire a 768x576 grey image
\endcode

The grabber allows also to grab a portion of an image using a region of interest. The following example shows how to grab a 320x240 region located on the top/left corner of the image that has a higher resolution (ie 640x480).

#include <visp3/gui/vpDisplayX.h>
#include <visp3/io/vpImageIo.h>
#include <visp3/sensor/vpV4l2Grabber.h>
 
int main()
{
#if defined(VISP_HAVE_V4L2) && defined(VISP_HAVE_X11)
  vpDisplayX *d;
  vpImage<vpRGBa> I;
  vpRect roi(0, 0, 320, 240); // specify the region to crop
 
  vpV4l2Grabber g;
 
  bool first = true;
  while (1) {
    g.acquire(I, roi);
    if(first) {
      d = new vpDisplayX(I);
      first = false;
    }
    vpDisplay::display(I);
    vpDisplay::flush(I);
    if (vpDisplay::getClick(I, false))
      break;
  }
  vpImageIo::write(I, "image.pgm"); // Save the last image
  delete d;
#endif

Definition at line 146 of file vpV4l2Grabber.cpp.

References buf_me, buf_v4l2, cap, ctl, DEFAULT_INPUT, DEFAULT_SCALE, device, fd, field, fmt, fmt_me, fmt_v4l2, framerate_25fps, index_buffer, vpFrameGrabber::init, inp, m_frameformat, m_framerate, m_input, m_nbuffers, m_pixelformat, m_verbose, queue, reqbufs, setDevice(), setFramerate(), setInput(), setNBuffers(), setScale(), std, streaming, streamparm, V4L2_FRAME_FORMAT, V4L2_YUYV_FORMAT, vpV4l2Grabber(), and waiton_cpt.

Referenced by open(), operator>>(), operator>>(), vpV4l2Grabber(), vpV4l2Grabber(), vpV4l2Grabber(), vpV4l2Grabber(), and vpV4l2Grabber().

◆ vpV4l2Grabber() [2/5]

vpV4l2Grabber::vpV4l2Grabber ( bool verbose )

explicit

Default constructor.

Setup the Video For Linux Two (V4L2) driver in streaming mode.

Parameters

verbose : If true activates the verbose mode.

Default settings are:

Device name: /dev/video0: To change it use setDevice()
Number of ring buffers: 3. To change this value use setNBuffers(). For non real-time applications the number of buffers should be set to 1. For real-time applications to reach 25 fps or 50 fps a good compromise is to set the number of buffers to 3.
Framerate acquisition: 25 fps. Use setFramerate() to set 25 fps or 50 fps. These framerates are reachable only if enought buffers are set.
Input board: vpV4l2Grabber::DEFAULT_INPUT. Video input port. Use setInput() to change it.
Image size acquisition: vpV4l2Grabber::DEFAULT_SCALE. Use either setScale() or setWidth() and setHeight to change it.

vpImage<unsigned char> I; // Grey level image

vpV4l2Grabber g(true); // Activates the verbose mode

g.setInput(2); // Input 2 on the board

g.setWidth(768); // Acquired images are 768 width

g.setHeight(576); // Acquired images are 576 height

g.setNBuffers(3); // 3 ring buffers to ensure real-time acquisition

g.open(I); // Open the grabber

g.acquire(I); // Acquire a 768x576 grey image

Definition at line 202 of file vpV4l2Grabber.cpp.

References buf_me, buf_v4l2, cap, ctl, DEFAULT_INPUT, DEFAULT_SCALE, device, fd, field, fmt, fmt_me, fmt_v4l2, framerate_25fps, index_buffer, vpFrameGrabber::init, inp, m_frameformat, m_framerate, m_input, m_nbuffers, m_pixelformat, m_verbose, queue, reqbufs, setDevice(), setFramerate(), setInput(), setNBuffers(), setScale(), std, streaming, streamparm, V4L2_FRAME_FORMAT, V4L2_YUYV_FORMAT, vpV4l2Grabber(), and waiton_cpt.

◆ vpV4l2Grabber() [3/5]

vpV4l2Grabber::vpV4l2Grabber	(	unsigned	input,
		unsigned	scale = vpV4l2Grabber::DEFAULT_SCALE )

Constructor.

Setup the Video For Linux Two (V4L2) driver in streaming mode.

Parameters

input	: Video input port.
scale	: Decimation factor.

Default settings are:

Device name: /dev/video0: To change it use setDevice()
Number of ring buffers: 3. To change this value use setNBuffers(). For non real-time applications the number of buffers should be set to 1. For real-time applications to reach 25 fps or 50 fps a good compromise is to set the number of buffers to 3.
Framerate acquisition: 25 fps. Use setFramerate() to set 25 fps or 50 fps. These framerates are reachable only if enought buffers are set.

vpImage<unsigned char> I; // Grey level image

vpV4l2Grabber g(1, 2); // Select input 1, and half full size resolution images.

g.open(I); // Open the grabber

g.acquire(I); // Acquire a 384x288 grey image

Definition at line 248 of file vpV4l2Grabber.cpp.

References buf_me, buf_v4l2, cap, ctl, DEFAULT_INPUT, device, fd, field, fmt, fmt_me, fmt_v4l2, framerate_25fps, index_buffer, vpFrameGrabber::init, inp, m_frameformat, m_framerate, m_input, m_nbuffers, m_pixelformat, m_verbose, queue, reqbufs, setDevice(), setFramerate(), setInput(), setNBuffers(), setScale(), std, streaming, streamparm, V4L2_FRAME_FORMAT, V4L2_YUYV_FORMAT, vpV4l2Grabber(), and waiton_cpt.

◆ vpV4l2Grabber() [4/5]

vpV4l2Grabber::vpV4l2Grabber	(	vpImage< unsigned char > &	I,
		unsigned	input,
		unsigned	scale = vpV4l2Grabber::DEFAULT_SCALE )

Constructor.

Setup the Video For Linux Two (V4L2) driver in streaming mode.

Parameters

I	: Image data structure (grey 8 bits image)
input	: Video input port.
scale	: Decimation factor.

Default settings are:

Device name: /dev/video0: To change it use setDevice()
Number of ring buffers: 3. To change this value use setNBuffers(). For non real-time applications the number of buffers should be set to 1. For real-time applications to reach 25 fps or 50 fps a good compromise is to set the number of buffers to 3.
Framerate acquisition: 25 fps. Use setFramerate() to set 25 fps or 50 fps. These framerates are reachable only if enought buffers are set.

vpImage<unsigned char> I; // Grey level image

vpV4l2Grabber g(I, 1, 2); // Select input 1, and half full size resolution

// images and open the grabber

g.acquire(I); // Acquire a 384x288 grey image

Definition at line 294 of file vpV4l2Grabber.cpp.

References buf_me, buf_v4l2, cap, ctl, DEFAULT_INPUT, device, fd, field, fmt, fmt_me, fmt_v4l2, framerate_25fps, index_buffer, vpFrameGrabber::init, inp, m_frameformat, m_framerate, m_input, m_nbuffers, m_pixelformat, m_verbose, open(), queue, reqbufs, setDevice(), setFramerate(), setInput(), setNBuffers(), setScale(), std, streaming, streamparm, V4L2_FRAME_FORMAT, V4L2_YUYV_FORMAT, vpV4l2Grabber(), and waiton_cpt.

◆ vpV4l2Grabber() [5/5]

vpV4l2Grabber::vpV4l2Grabber	(	vpImage< vpRGBa > &	I,
		unsigned	input,
		unsigned	scale = vpV4l2Grabber::DEFAULT_SCALE )

Constructor.

Setup the Video For Linux Two (V4L2) driver in streaming mode.

Parameters

I	: Image data structure (Color RGB32 bits image)
input	: Video input port.
scale	: Decimation factor.

Default settings are:

Device name: /dev/video0: To change it use setDevice()
Number of ring buffers: 3. To change this value use setNBuffers(). For non real-time applications the number of buffers should be set to 1. For real-time applications to reach 25 fps or 50 fps a good compromise is to set the number of buffers to 3.
Framerate acquisition: 25 fps. Use setFramerate() to set 25 fps or 50 fps. These framerates are reachable only if enought buffers are set.

vpImage<vpRGBa> I; // Color image

vpV4l2Grabber g(I, 1, 2); // Select input 1, and half full size resolution

// images and open the grabber

g.acquire(I); // Acquire a 384x288 color image

Definition at line 343 of file vpV4l2Grabber.cpp.

References buf_me, buf_v4l2, cap, ctl, DEFAULT_INPUT, device, fd, field, fmt, fmt_me, fmt_v4l2, framerate_25fps, index_buffer, vpFrameGrabber::init, inp, m_frameformat, m_framerate, m_input, m_nbuffers, m_pixelformat, m_verbose, open(), queue, reqbufs, setDevice(), setFramerate(), setInput(), setNBuffers(), setScale(), std, streaming, streamparm, V4L2_FRAME_FORMAT, V4L2_YUYV_FORMAT, vpV4l2Grabber(), and waiton_cpt.

◆ ~vpV4l2Grabber()

vpV4l2Grabber::~vpV4l2Grabber ( )

virtual

Destructor.

See also: close()

Definition at line 365 of file vpV4l2Grabber.cpp.

References vpFrameGrabber::close().

Member Function Documentation

◆ acquire() [1/6]

void vpV4l2Grabber::acquire ( vpImage< unsigned char > & I )

virtual

Acquire a grey level image.

Parameters

I	: Image data structure (8 bits image)

Exceptions

vpFrameGrabberException::initializationError : Frame grabber not initialized.

See also: getField()

Implements vpFrameGrabber.

Examples: HelloWorldOgre.cpp, HelloWorldOgreAdvanced.cpp, grabV4l2.cpp, grabV4l2MultiCpp11Thread.cpp, manGrabV4l2.cpp, mbot-apriltag-2D-half-vs.cpp, mbot-apriltag-ibvs.cpp, mbot-apriltag-pbvs.cpp, servoPioneerPanSegment3D.cpp, tutorial-apriltag-detector-live.cpp, tutorial-barcode-detector-live.cpp, tutorial-blob-tracker-live-v4l2.cpp, tutorial-face-detector-live.cpp, tutorial-grabber-v4l2-threaded.cpp, tutorial-klt-tracker-live-v4l2.cpp, tutorial-mb-generic-tracker-apriltag-webcam.cpp, tutorial-mb-generic-tracker-live.cpp, tutorial-pose-from-points-live.cpp, and tutorial-video-recorder.cpp.

Definition at line 527 of file vpV4l2Grabber.cpp.

References acquire().

Referenced by acquire(), acquire(), acquire(), acquire(), operator>>(), and operator>>().

◆ acquire() [2/6]

void vpV4l2Grabber::acquire	(	vpImage< unsigned char > &	I,
		const vpRect &	roi )

Acquire a grey level image.

Parameters

I	: Image data structure (8 bits image)
roi	: Region of interest to grab from the full resolution image.

Exceptions

vpFrameGrabberException::initializationError : Frame grabber not initialized.

See also: getField()

Definition at line 546 of file vpV4l2Grabber.cpp.

References acquire().

◆ acquire() [3/6]

void vpV4l2Grabber::acquire	(	vpImage< unsigned char > &	I,
		struct timeval &	timestamp,
		const vpRect &	roi = vpRect() )

Acquire a grey level image.

Parameters

I	: Image data structure (8 bits image).
timestamp	: Timeval data structure providing the unix time at which the frame was captured in the ringbuffer. Warning: some v4l2 drivers do not return the time since 1970 (the one returned by gettimeofday() or vpTime) but rather a time that counts from the boot time (i.e. uptime).
roi	: Region of interest to grab from the full resolution image. By default acquire the whole image.

Exceptions

vpFrameGrabberException::initializationError : Frame grabber not initialized.

See also: getField()

Definition at line 572 of file vpV4l2Grabber.cpp.

References vpImageConvert::BGRToGrey(), vpImage< Type >::bitmap, vpFrameGrabber::close(), vpImageTools::crop(), vpRect::getHeight(), vpRect::getWidth(), vpFrameGrabber::height, index_buffer, vpFrameGrabber::init, vpFrameGrabberException::initializationError, m_pixelformat, open(), queueAll(), vpImageConvert::RGBaToGrey(), vpImageConvert::RGBToGrey(), V4L2_BGR24_FORMAT, V4L2_GREY_FORMAT, V4L2_RGB24_FORMAT, V4L2_RGB32_FORMAT, V4L2_YUYV_FORMAT, waiton(), vpFrameGrabber::width, and vpImageConvert::YUYVToGrey().

◆ acquire() [4/6]

void vpV4l2Grabber::acquire ( vpImage< vpRGBa > & I )

virtual

Acquire a color image.

Parameters

I	: Image data structure (32 bits image)

Exceptions

vpFrameGrabberException::initializationError : Frame grabber not initialized.

See also: getField()

Implements vpFrameGrabber.

Definition at line 653 of file vpV4l2Grabber.cpp.

References acquire().

◆ acquire() [5/6]

void vpV4l2Grabber::acquire	(	vpImage< vpRGBa > &	I,
		const vpRect &	roi )

Acquire a color image.

Parameters

I	: Image data structure (32 bits image)
roi	: Region of interest to grab from the full resolution image.

Exceptions

vpFrameGrabberException::initializationError : Frame grabber not initialized.

See also: getField()

Definition at line 672 of file vpV4l2Grabber.cpp.

References acquire().

◆ acquire() [6/6]

void vpV4l2Grabber::acquire	(	vpImage< vpRGBa > &	I,
		struct timeval &	timestamp,
		const vpRect &	roi = vpRect() )

Acquire a color image.

Parameters

I	: Image data structure (32 bits image).
timestamp	: Timeval data structure providing the unix time at which the frame was captured in the ringbuffer. Warning: some v4l2 drivers do not return the time since 1970 (the one returned by gettimeofday() or vpTime) but rather a time that counts from the boot time (i.e. uptime).
roi	: Region of interest to grab from the full resolution image. By default acquire the whole image.

Exceptions

vpFrameGrabberException::initializationError : Frame grabber not initialized.

See also: getField()

Definition at line 698 of file vpV4l2Grabber.cpp.

References vpImageConvert::BGRToRGBa(), vpImage< Type >::bitmap, vpFrameGrabber::close(), vpImageTools::crop(), vpRect::getHeight(), vpRect::getLeft(), vpRect::getTop(), vpRect::getWidth(), vpImageConvert::GreyToRGBa(), vpFrameGrabber::height, index_buffer, vpFrameGrabber::init, vpFrameGrabberException::initializationError, m_pixelformat, open(), queueAll(), vpImageConvert::RGBToRGBa(), V4L2_BGR24_FORMAT, V4L2_GREY_FORMAT, V4L2_RGB24_FORMAT, V4L2_RGB32_FORMAT, V4L2_YUYV_FORMAT, waiton(), vpFrameGrabber::width, and vpImageConvert::YUYVToRGBa().

◆ close()

virtual void vpFrameGrabber::close ( )

pure virtualinherited

This virtual function is used to de-allocate the memory used by a specific frame grabber

Implemented in vp1394CMUGrabber, vp1394TwoGrabber, vpDirectShowGrabber, vpDiskGrabber, vpFlyCaptureGrabber, vpPylonGrabber, vpPylonGrabberGigE, vpPylonGrabberUsb, and vpVideoReader.

Examples: grabV4l2.cpp.

Referenced by vpV4l2Grabber::acquire(), vpV4l2Grabber::acquire(), vpV4l2Grabber::getCapabilities(), vpV4l2Grabber::getField(), vpV4l2Grabber::open(), vpV4l2Grabber::open(), vpV4l2Grabber::setScale(), and vpV4l2Grabber::~vpV4l2Grabber().

◆ getCapabilities()

void vpV4l2Grabber::getCapabilities ( )

Get device capabilities.

Exceptions

vpFrameGrabberException::otherError : Can't get video parameters.

Definition at line 1000 of file vpV4l2Grabber.cpp.

References vpFrameGrabber::close(), fd, fmt, inp, MAX_FORMAT, MAX_INPUTS, MAX_NORM, vpFrameGrabberException::otherError, std, and streamparm.

Referenced by open().

◆ getField()

bool vpV4l2Grabber::getField ( )

Return the field (odd or even) corresponding to the last acquired frame.

This method is to call after acquire() and has only a mean if the acquisition framerate is set to 50 fps.

Returns: Field of the acquired frame (0 if odd field, 1 if even field).

Exceptions

vpFrameGrabberException::otherError : Video device returns a bad frame field.

See also: acquire(), setFramerate()

Definition at line 794 of file vpV4l2Grabber.cpp.

References vpFrameGrabber::close(), field, and vpFrameGrabberException::otherError.

◆ getFramerate()

vpV4l2Grabber::vpV4l2FramerateType vpV4l2Grabber::getFramerate ( )

Return the framerate of the acquisition.

Returns: The actual framerate of the framegrabber.

See also: setFramerate()

Definition at line 840 of file vpV4l2Grabber.cpp.

References m_framerate.

◆ getHeight()

unsigned int vpFrameGrabber::getHeight ( ) const

inlineinherited

Return the number of rows in the image.

Examples: AROgre.cpp, AROgreBasic.cpp, and testPylonGrabber.cpp.

Definition at line 109 of file vpFrameGrabber.h.

References height.

◆ getPixelFormat()

vpV4l2PixelFormatType vpV4l2Grabber::getPixelFormat ( )

inline

Get the pixel format used for capture.

Returns: Camera pixel format coding.

Definition at line 237 of file vpV4l2Grabber.h.

References m_pixelformat.

Referenced by open(), and open().

◆ getWidth()

unsigned int vpFrameGrabber::getWidth ( ) const

inlineinherited

Return the number of columns in the image.

Examples: AROgre.cpp, AROgreBasic.cpp, and testPylonGrabber.cpp.

Definition at line 111 of file vpFrameGrabber.h.

References width.

◆ open() [1/3]

void vpV4l2Grabber::open ( )

Open the Video For Linux Two device.

Exceptions

vpFrameGrabberException::initializationError	: Can't access to video device.
vpFrameGrabberException::otherError	: Can't query video capabilities.

Definition at line 893 of file vpV4l2Grabber.cpp.

References buf_me, buf_v4l2, cap, vpFrameGrabber::close(), ctl, device, fd, fmt, getCapabilities(), vpFrameGrabberException::initializationError, inp, m_verbose, MAX_BUFFERS, MAX_CTRL, MAX_FORMAT, MAX_INPUTS, MAX_NORM, vpFrameGrabberException::otherError, std, streamparm, vpERROR_TRACE, and vpV4l2Grabber().

Referenced by acquire(), acquire(), open(), open(), vpV4l2Grabber(), and vpV4l2Grabber().

◆ open() [2/3]

void vpV4l2Grabber::open ( vpImage< unsigned char > & I )

virtual

Initialize image acquisition in grey format. Set the pixel format acquisition to vpV4l2Grabber::V4L2_GREY_FORMAT.

Parameters

I	: Image data structure (8 bits image). Once the device is open, the image is resized to the current acquisition size.

Exceptions

vpFrameGrabberException::settingError : Wrong input channel.

Implements vpFrameGrabber.

Examples: HelloWorldOgre.cpp, HelloWorldOgreAdvanced.cpp, grabV4l2.cpp, grabV4l2MultiCpp11Thread.cpp, manGrabV4l2.cpp, servoPioneerPanSegment3D.cpp, tutorial-apriltag-detector-live.cpp, tutorial-blob-tracker-live-v4l2.cpp, tutorial-face-detector-live-threaded.cpp, tutorial-grabber-v4l2-threaded.cpp, tutorial-klt-tracker-live-v4l2.cpp, tutorial-mb-generic-tracker-live.cpp, tutorial-pose-from-points-live.cpp, and tutorial-video-recorder.cpp.

Definition at line 407 of file vpV4l2Grabber.cpp.

References vpFrameGrabber::close(), fd, getPixelFormat(), vpFrameGrabber::height, vpFrameGrabber::init, m_input, m_pixelformat, m_verbose, open(), vpFrameGrabberException::settingError, startStreaming(), V4L2_MAX_FORMAT, and vpFrameGrabber::width.

◆ open() [3/3]

void vpV4l2Grabber::open ( vpImage< vpRGBa > & I )

virtual

Initialize image acquisition in color RGB32 format. Set the pixel format acquisition to vpV4l2Grabber::V4L2_RGB32_FORMAT.

Parameters

I	: Image data structure (RGB32 bits image). Once the device is open, the image is resized to the current acquisition size.

Implements vpFrameGrabber.

Definition at line 470 of file vpV4l2Grabber.cpp.

References fd, getPixelFormat(), vpFrameGrabber::height, vpFrameGrabber::init, m_input, m_pixelformat, m_verbose, open(), startStreaming(), V4L2_MAX_FORMAT, and vpFrameGrabber::width.

◆ operator>>() [1/2]

vpV4l2Grabber & vpV4l2Grabber::operator>> ( vpImage< unsigned char > & I )

Operator that allows to capture a grey level image.

Parameters

I	: The captured image.

#include <visp3/sensor/vpV4l2Grabber.h>
 
int main()
{
  vpImage<unsigned char> I;
  vpV4l2Grabber g;
  g >> I;
}

Definition at line 1442 of file vpV4l2Grabber.cpp.

References acquire(), and vpV4l2Grabber().

◆ operator>>() [2/2]

vpV4l2Grabber & vpV4l2Grabber::operator>> ( vpImage< vpRGBa > & I )

Operator that allows to capture a grey level image.

Parameters

I	: The captured image.

#include <visp3/sensor/vpV4l2Grabber.h>
 
int main()
{
  vpImage<vpRGBa> I;
  vpV4l2Grabber g;
  g >> I;
}

Definition at line 1464 of file vpV4l2Grabber.cpp.

References acquire(), and vpV4l2Grabber().

◆ printBufInfo()

void vpV4l2Grabber::printBufInfo ( struct v4l2_buffer buf )

Get device capabilities.

Definition at line 1397 of file vpV4l2Grabber.cpp.

Referenced by startStreaming(), and stopStreaming().

◆ queueAll()

void vpV4l2Grabber::queueAll ( )

Call the queue buffer private method if needed

Definition at line 1380 of file vpV4l2Grabber.cpp.

References queue, queueBuffer(), reqbufs, and waiton_cpt.

Referenced by acquire(), acquire(), and startStreaming().

◆ queueBuffer()

int vpV4l2Grabber::queueBuffer ( )

Capture helpers.

Definition at line 1339 of file vpV4l2Grabber.cpp.

References buf_me, buf_v4l2, fd, vpFrameGrabberException::otherError, queue, reqbufs, and waiton_cpt.

Referenced by queueAll().

◆ setDevice()

void vpV4l2Grabber::setDevice ( const std::string & devname )

inline

Set the device name.

Parameters

devname : Device name (like /dev/video0).

Examples: grabV4l2.cpp, grabV4l2MultiCpp11Thread.cpp, mbot-apriltag-2D-half-vs.cpp, mbot-apriltag-ibvs.cpp, mbot-apriltag-pbvs.cpp, servoPioneerPanSegment3D.cpp, tutorial-apriltag-detector-live.cpp, tutorial-barcode-detector-live.cpp, tutorial-blob-tracker-live-v4l2.cpp, tutorial-face-detector-live-threaded.cpp, tutorial-face-detector-live.cpp, tutorial-grabber-v4l2-threaded.cpp, tutorial-grabber-v4l2.cpp, tutorial-klt-tracker-live-v4l2.cpp, tutorial-mb-generic-tracker-apriltag-webcam.cpp, tutorial-mb-generic-tracker-live.cpp, tutorial-pose-from-points-live.cpp, and tutorial-video-recorder.cpp.

Definition at line 283 of file vpV4l2Grabber.h.

References device.

Referenced by vpV4l2Grabber(), vpV4l2Grabber(), vpV4l2Grabber(), vpV4l2Grabber(), and vpV4l2Grabber().

◆ setFrameFormat()

void vpV4l2Grabber::setFrameFormat ( vpV4l2FrameFormatType frameformat )

inline

Set the pixel format for capture.`If the specified pixel format is out of range, we set the V4L2_RGB24_FORMAT.

Parameters

pixelformat : Camera pixel format coding.

*/ inline void setPixelFormat(vpV4l2PixelFormatType pixelformat) { this->m_pixelformat = pixelformat; if (this->m_pixelformat >= V4L2_MAX_FORMAT) this->m_pixelformat = V4L2_RGB24_FORMAT; }

void close();

private: void setFormat(); /*! Set the frame format.

Parameters

frameformat

:

vpV4l2Grabber::V4L2_FRAME_FORMAT: capture alternate fields (or frames),
vpV4l2Grabber::V4L2_IMAGE_FORMAT: capture interlaced images.

Definition at line 310 of file vpV4l2Grabber.h.

References m_frameformat.

Referenced by setFramerate().

◆ setFramerate()

void vpV4l2Grabber::setFramerate ( vpV4l2Grabber::vpV4l2FramerateType framerate )

Set the frame format depending on the framerate acquisition.

Parameters

framerate

: The framerate for the acquisition.

If vpV4l2Grabber::framerate_25fps use vpV4l2Grabber::V4L2_IMAGE_FORMAT,
else if vpV4l2Grabber::framerate_50fps use vpV4l2Grabber::V4L2_FRAME_FORMAT.

Warning: If you want to acquire frames at 25 fps or 50 fps, you have to be aware of the number of buffers required for the streaming. A typical value could be 3 (see setNBuffers()).

See also: getFramerate(), setNBuffers()

Examples: grabV4l2.cpp, and servoPioneerPanSegment3D.cpp.

Definition at line 821 of file vpV4l2Grabber.cpp.

References framerate_25fps, m_framerate, setFrameFormat(), V4L2_FRAME_FORMAT, and V4L2_IMAGE_FORMAT.

Referenced by vpV4l2Grabber(), vpV4l2Grabber(), vpV4l2Grabber(), vpV4l2Grabber(), and vpV4l2Grabber().

◆ setHeight()

void vpV4l2Grabber::setHeight ( unsigned h )

inline

Set image height to acquire.

Examples: manGrabV4l2.cpp.

Definition at line 260 of file vpV4l2Grabber.h.

References vpFrameGrabber::height.

Referenced by setScale().

◆ setInput()

void vpV4l2Grabber::setInput ( unsigned input = vpV4l2Grabber::DEFAULT_INPUT )

Set the video input port on the board.

Examples: grabV4l2.cpp, manGrabV4l2.cpp, and servoPioneerPanSegment3D.cpp.

Definition at line 370 of file vpV4l2Grabber.cpp.

References m_input.

Referenced by vpV4l2Grabber(), vpV4l2Grabber(), vpV4l2Grabber(), vpV4l2Grabber(), and vpV4l2Grabber().

◆ setNBuffers()

void vpV4l2Grabber::setNBuffers ( unsigned nbuffers )

inline

Set the number of buffers required for streaming data.

For non real-time applications the number of buffers should be set to 1. For real-time applications to reach 25 fps or 50 fps a good compromise is to set the number of buffers to 3.

Parameters

nbuffers : Number of ring buffers.

Examples: manGrabV4l2.cpp.

Definition at line 275 of file vpV4l2Grabber.h.

References m_nbuffers.

Referenced by vpV4l2Grabber(), vpV4l2Grabber(), vpV4l2Grabber(), vpV4l2Grabber(), and vpV4l2Grabber().

◆ setScale()

void vpV4l2Grabber::setScale ( unsigned scale = vpV4l2Grabber::DEFAULT_SCALE )

Set the decimation factor applied to full resolution images (768x576).

Exceptions

vpFrameGrabberException::settingError : Wrong scale (should be between 1 and 16).

Parameters

scale : Decimation factor. If scale is set to 2, 384x288 images will be acquired.

An other way to specify the image size is to use setWidth() and setHeight().

Examples: grabV4l2.cpp, grabV4l2MultiCpp11Thread.cpp, mbot-apriltag-2D-half-vs.cpp, mbot-apriltag-ibvs.cpp, mbot-apriltag-pbvs.cpp, servoPioneerPanSegment3D.cpp, servoPioneerPoint2DDepth.cpp, servoPioneerPoint2DDepthWithoutVpServo.cpp, tutorial-apriltag-detector-live.cpp, tutorial-barcode-detector-live.cpp, tutorial-face-detector-live-threaded.cpp, tutorial-face-detector-live.cpp, tutorial-grabber-v4l2-threaded.cpp, tutorial-mb-generic-tracker-apriltag-webcam.cpp, tutorial-mb-generic-tracker-live.cpp, tutorial-pose-from-points-live.cpp, and tutorial-video-recorder.cpp.

Definition at line 384 of file vpV4l2Grabber.cpp.

References vpFrameGrabber::close(), setHeight(), vpFrameGrabberException::settingError, setWidth(), and vpERROR_TRACE.

Referenced by vpV4l2Grabber(), vpV4l2Grabber(), vpV4l2Grabber(), vpV4l2Grabber(), and vpV4l2Grabber().

◆ setVerboseMode()

void vpV4l2Grabber::setVerboseMode ( bool verbose )

inline

Activates the verbose mode to print additional information on stdout.

Parameters

verbose : If true activates the verbose mode.

Examples: grabV4l2.cpp.

Definition at line 246 of file vpV4l2Grabber.h.

References m_verbose.

◆ setWidth()

void vpV4l2Grabber::setWidth ( unsigned w )

inline

Set image width to acquire.

Examples: manGrabV4l2.cpp.

Definition at line 255 of file vpV4l2Grabber.h.

References vpFrameGrabber::width.

Referenced by setScale().

◆ startStreaming()

void vpV4l2Grabber::startStreaming ( )

Launch the streaming capture mode and map device memory into application address space.

Exceptions

vpFrameGrabberException::otherError : If a problem occurs.

Definition at line 1160 of file vpV4l2Grabber.cpp.

References buf_me, buf_v4l2, device, fd, fmt, fmt_me, fmt_v4l2, m_nbuffers, m_verbose, vpFrameGrabberException::otherError, printBufInfo(), queueAll(), reqbufs, stopStreaming(), and streaming.

Referenced by open(), and open().

◆ stopStreaming()

void vpV4l2Grabber::stopStreaming ( )

Stops the streaming capture mode and unmap the device memory.

Exceptions

vpFrameGrabberException::otherError : if can't stop streaming.

Definition at line 1227 of file vpV4l2Grabber.cpp.

References buf_me, buf_v4l2, fd, fmt_v4l2, m_verbose, vpFrameGrabberException::otherError, printBufInfo(), queue, reqbufs, streaming, and waiton_cpt.

Referenced by startStreaming().

◆ waiton()

unsigned char * vpV4l2Grabber::waiton	(	__u32 &	index,
		struct timeval &	timestamp )

Fill the next buffer. If all the buffers are filled return NULL.

Update the buffer index. If all the buffers are filled index is set to -1.

Parameters

index	: Index in the buffer where image is available.
timestamp	: Timeval data structure providing the unix time [microseconds] at which the frame was captured in the ringbuffer.

Exceptions

vpFrameGrabberException::otherError : If can't access to the frame.

Definition at line 1267 of file vpV4l2Grabber.cpp.

References buf_me, buf_v4l2, fd, field, vpFrameGrabberException::otherError, and waiton_cpt.

Referenced by acquire(), and acquire().

Member Data Documentation

◆ buf_me

struct ng_video_buf* vpV4l2Grabber::buf_me

Definition at line 335 of file vpV4l2Grabber.h.

Referenced by open(), queueBuffer(), startStreaming(), stopStreaming(), vpV4l2Grabber(), vpV4l2Grabber(), vpV4l2Grabber(), vpV4l2Grabber(), vpV4l2Grabber(), and waiton().

◆ buf_v4l2

struct v4l2_buffer* vpV4l2Grabber::buf_v4l2

Definition at line 334 of file vpV4l2Grabber.h.

Referenced by open(), queueBuffer(), startStreaming(), stopStreaming(), vpV4l2Grabber(), vpV4l2Grabber(), vpV4l2Grabber(), vpV4l2Grabber(), vpV4l2Grabber(), and waiton().

◆ cap

struct v4l2_capability vpV4l2Grabber::cap

Definition at line 323 of file vpV4l2Grabber.h.

Referenced by open(), vpV4l2Grabber(), vpV4l2Grabber(), vpV4l2Grabber(), vpV4l2Grabber(), and vpV4l2Grabber().

◆ ctl

struct v4l2_queryctrl* vpV4l2Grabber::ctl

Definition at line 328 of file vpV4l2Grabber.h.

Referenced by open(), vpV4l2Grabber(), vpV4l2Grabber(), vpV4l2Grabber(), vpV4l2Grabber(), and vpV4l2Grabber().

◆ DEFAULT_INPUT

const unsigned int vpV4l2Grabber::DEFAULT_INPUT = 2

static

Definition at line 135 of file vpV4l2Grabber.h.

Referenced by vpV4l2Grabber(), vpV4l2Grabber(), vpV4l2Grabber(), vpV4l2Grabber(), and vpV4l2Grabber().

◆ DEFAULT_SCALE

const unsigned int vpV4l2Grabber::DEFAULT_SCALE = 2

static

Definition at line 136 of file vpV4l2Grabber.h.

Referenced by vpV4l2Grabber(), and vpV4l2Grabber().

◆ device

std::string vpV4l2Grabber::device

Definition at line 321 of file vpV4l2Grabber.h.

Referenced by open(), setDevice(), startStreaming(), vpV4l2Grabber(), vpV4l2Grabber(), vpV4l2Grabber(), vpV4l2Grabber(), and vpV4l2Grabber().

◆ fd

int vpV4l2Grabber::fd

Definition at line 320 of file vpV4l2Grabber.h.

Referenced by getCapabilities(), open(), open(), open(), queueBuffer(), startStreaming(), stopStreaming(), vpV4l2Grabber(), vpV4l2Grabber(), vpV4l2Grabber(), vpV4l2Grabber(), vpV4l2Grabber(), and waiton().

◆ field

unsigned int vpV4l2Grabber::field

Definition at line 342 of file vpV4l2Grabber.h.

Referenced by getField(), vpV4l2Grabber(), vpV4l2Grabber(), vpV4l2Grabber(), vpV4l2Grabber(), vpV4l2Grabber(), and waiton().

◆ fmt

struct v4l2_fmtdesc* vpV4l2Grabber::fmt

Definition at line 327 of file vpV4l2Grabber.h.

Referenced by getCapabilities(), open(), startStreaming(), vpV4l2Grabber(), vpV4l2Grabber(), vpV4l2Grabber(), vpV4l2Grabber(), and vpV4l2Grabber().

◆ fmt_me

struct ng_video_fmt vpV4l2Grabber::fmt_me

Definition at line 332 of file vpV4l2Grabber.h.

Referenced by startStreaming(), vpV4l2Grabber(), vpV4l2Grabber(), vpV4l2Grabber(), vpV4l2Grabber(), and vpV4l2Grabber().

◆ fmt_v4l2

struct v4l2_format vpV4l2Grabber::fmt_v4l2

Definition at line 331 of file vpV4l2Grabber.h.

Referenced by startStreaming(), stopStreaming(), vpV4l2Grabber(), vpV4l2Grabber(), vpV4l2Grabber(), vpV4l2Grabber(), and vpV4l2Grabber().

◆ FRAME_SIZE

const unsigned int vpV4l2Grabber::FRAME_SIZE = 288

static

Definition at line 142 of file vpV4l2Grabber.h.

◆ height

unsigned int vpFrameGrabber::height

protectedinherited

Number of rows in the image.

Definition at line 102 of file vpFrameGrabber.h.

◆ index_buffer

__u32 vpV4l2Grabber::index_buffer

index of the buffer in use

Definition at line 338 of file vpV4l2Grabber.h.

Referenced by acquire(), acquire(), vpV4l2Grabber(), vpV4l2Grabber(), vpV4l2Grabber(), vpV4l2Grabber(), and vpV4l2Grabber().

◆ init

bool vpFrameGrabber::init

inherited

Set to true if the frame grabber has been initialized.

Definition at line 99 of file vpFrameGrabber.h.

Referenced by vpV4l2Grabber::acquire(), vpV4l2Grabber::acquire(), vp1394CMUGrabber::close(), vp1394TwoGrabber::close(), vpFlyCaptureGrabber::connect(), vpPylonGrabberGigE::connect(), vpPylonGrabberUsb::connect(), vpFlyCaptureGrabber::disconnect(), vpPylonGrabberGigE::disconnect(), vpPylonGrabberUsb::disconnect(), vpDiskGrabber::open(), vpDiskGrabber::open(), vpDiskGrabber::open(), vpV4l2Grabber::open(), vpV4l2Grabber::open(), vp1394TwoGrabber::resetBus(), vpFlyCaptureGrabber::startCapture(), vpPylonGrabberGigE::startCapture(), vpPylonGrabberUsb::startCapture(), vpFlyCaptureGrabber::stopCapture(), vpPylonGrabberGigE::stopCapture(), vpPylonGrabberUsb::stopCapture(), vp1394CMUGrabber::vp1394CMUGrabber(), vp1394TwoGrabber::vp1394TwoGrabber(), vpDiskGrabber::vpDiskGrabber(), vpDiskGrabber::vpDiskGrabber(), vpDiskGrabber::vpDiskGrabber(), vpFrameGrabber(), vpV4l2Grabber::vpV4l2Grabber(), vpV4l2Grabber::vpV4l2Grabber(), vpV4l2Grabber::vpV4l2Grabber(), vpV4l2Grabber::vpV4l2Grabber(), and vpV4l2Grabber::vpV4l2Grabber().

◆ inp

struct v4l2_input* vpV4l2Grabber::inp

Definition at line 325 of file vpV4l2Grabber.h.

Referenced by getCapabilities(), open(), vpV4l2Grabber(), vpV4l2Grabber(), vpV4l2Grabber(), vpV4l2Grabber(), and vpV4l2Grabber().

◆ m_frameformat

vpV4l2FrameFormatType vpV4l2Grabber::m_frameformat

Definition at line 347 of file vpV4l2Grabber.h.

Referenced by setFrameFormat(), vpV4l2Grabber(), vpV4l2Grabber(), vpV4l2Grabber(), vpV4l2Grabber(), and vpV4l2Grabber().

◆ m_framerate

vpV4l2FramerateType vpV4l2Grabber::m_framerate

Definition at line 346 of file vpV4l2Grabber.h.

Referenced by getFramerate(), setFramerate(), vpV4l2Grabber(), vpV4l2Grabber(), vpV4l2Grabber(), vpV4l2Grabber(), and vpV4l2Grabber().

◆ m_input

unsigned vpV4l2Grabber::m_input

Definition at line 345 of file vpV4l2Grabber.h.

Referenced by open(), open(), setInput(), vpV4l2Grabber(), vpV4l2Grabber(), vpV4l2Grabber(), vpV4l2Grabber(), and vpV4l2Grabber().

◆ m_nbuffers

unsigned vpV4l2Grabber::m_nbuffers

Definition at line 341 of file vpV4l2Grabber.h.

Referenced by setNBuffers(), startStreaming(), vpV4l2Grabber(), vpV4l2Grabber(), vpV4l2Grabber(), vpV4l2Grabber(), and vpV4l2Grabber().

◆ m_pixelformat

vpV4l2PixelFormatType vpV4l2Grabber::m_pixelformat

Definition at line 348 of file vpV4l2Grabber.h.

Referenced by acquire(), acquire(), getPixelFormat(), open(), open(), vpV4l2Grabber(), vpV4l2Grabber(), vpV4l2Grabber(), vpV4l2Grabber(), and vpV4l2Grabber().

◆ m_verbose

bool vpV4l2Grabber::m_verbose

Definition at line 340 of file vpV4l2Grabber.h.

Referenced by open(), open(), open(), setVerboseMode(), startStreaming(), stopStreaming(), vpV4l2Grabber(), vpV4l2Grabber(), vpV4l2Grabber(), vpV4l2Grabber(), and vpV4l2Grabber().

◆ MAX_BUFFERS

const unsigned int vpV4l2Grabber::MAX_BUFFERS = 32

static

Definition at line 141 of file vpV4l2Grabber.h.

Referenced by open().

◆ MAX_CTRL

const unsigned int vpV4l2Grabber::MAX_CTRL = 32

static

Definition at line 140 of file vpV4l2Grabber.h.

Referenced by open().

◆ MAX_FORMAT

const __u32 vpV4l2Grabber::MAX_FORMAT = 32

static

Definition at line 139 of file vpV4l2Grabber.h.

Referenced by getCapabilities(), and open().

◆ MAX_INPUTS

const __u32 vpV4l2Grabber::MAX_INPUTS = 16

static

Definition at line 137 of file vpV4l2Grabber.h.

Referenced by getCapabilities(), and open().

◆ MAX_NORM

const __u32 vpV4l2Grabber::MAX_NORM = 16

static

Definition at line 138 of file vpV4l2Grabber.h.

Referenced by getCapabilities(), and open().

◆ queue

unsigned int vpV4l2Grabber::queue

Definition at line 336 of file vpV4l2Grabber.h.

Referenced by queueAll(), queueBuffer(), stopStreaming(), vpV4l2Grabber(), vpV4l2Grabber(), vpV4l2Grabber(), vpV4l2Grabber(), and vpV4l2Grabber().

◆ reqbufs

struct v4l2_requestbuffers vpV4l2Grabber::reqbufs

Definition at line 333 of file vpV4l2Grabber.h.

Referenced by queueAll(), queueBuffer(), startStreaming(), stopStreaming(), vpV4l2Grabber(), vpV4l2Grabber(), vpV4l2Grabber(), vpV4l2Grabber(), and vpV4l2Grabber().

◆ std

struct v4l2_standard* vpV4l2Grabber::std

Definition at line 326 of file vpV4l2Grabber.h.

Referenced by getCapabilities(), open(), vpV4l2Grabber(), vpV4l2Grabber(), vpV4l2Grabber(), vpV4l2Grabber(), and vpV4l2Grabber().

◆ streaming

bool vpV4l2Grabber::streaming

Definition at line 343 of file vpV4l2Grabber.h.

Referenced by startStreaming(), stopStreaming(), vpV4l2Grabber(), vpV4l2Grabber(), vpV4l2Grabber(), vpV4l2Grabber(), and vpV4l2Grabber().

◆ streamparm

struct v4l2_streamparm vpV4l2Grabber::streamparm

Definition at line 324 of file vpV4l2Grabber.h.

Referenced by getCapabilities(), open(), vpV4l2Grabber(), vpV4l2Grabber(), vpV4l2Grabber(), vpV4l2Grabber(), and vpV4l2Grabber().

◆ waiton_cpt

unsigned int vpV4l2Grabber::waiton_cpt

Definition at line 337 of file vpV4l2Grabber.h.

Referenced by queueAll(), queueBuffer(), stopStreaming(), vpV4l2Grabber(), vpV4l2Grabber(), vpV4l2Grabber(), vpV4l2Grabber(), vpV4l2Grabber(), and waiton().

◆ width

unsigned int vpFrameGrabber::width

protectedinherited

Number of columns in the image.

Definition at line 103 of file vpFrameGrabber.h.

Public Types

Public Member Functions

Public Attributes

Static Public Attributes

Protected Attributes

Detailed Description

Member Enumeration Documentation

◆ vpV4l2FrameFormatType

◆ vpV4l2FramerateType

◆ vpV4l2PixelFormatType

Constructor & Destructor Documentation

◆ vpV4l2Grabber() [1/5]

◆ vpV4l2Grabber() [2/5]

◆ vpV4l2Grabber() [3/5]

◆ vpV4l2Grabber() [4/5]

◆ vpV4l2Grabber() [5/5]

◆ ~vpV4l2Grabber()

Member Function Documentation

◆ acquire() [1/6]

◆ acquire() [2/6]

◆ acquire() [3/6]

◆ acquire() [4/6]

◆ acquire() [5/6]

◆ acquire() [6/6]

◆ close()

◆ getCapabilities()

◆ getField()

◆ getFramerate()

◆ getHeight()

◆ getPixelFormat()

◆ getWidth()

◆ open() [1/3]

◆ open() [2/3]

◆ open() [3/3]

◆ operator>>() [1/2]

◆ operator>>() [2/2]

◆ printBufInfo()

◆ queueAll()

◆ queueBuffer()

◆ setDevice()

◆ setFrameFormat()

◆ setFramerate()

◆ setHeight()

◆ setInput()

◆ setNBuffers()

◆ setScale()

◆ setVerboseMode()

◆ setWidth()

◆ startStreaming()

◆ stopStreaming()

◆ waiton()

Member Data Documentation

◆ buf_me

◆ buf_v4l2

◆ cap

◆ ctl

◆ DEFAULT_INPUT

◆ DEFAULT_SCALE

◆ device

◆ fd

◆ field

◆ fmt

◆ fmt_me

◆ fmt_v4l2

◆ FRAME_SIZE

◆ height

◆ index_buffer

◆ init

◆ inp

◆ m_frameformat

◆ m_framerate

◆ m_input

◆ m_nbuffers

◆ m_pixelformat

◆ m_verbose

◆ MAX_BUFFERS

◆ MAX_CTRL

◆ MAX_FORMAT

◆ MAX_INPUTS

◆ MAX_NORM