grabV4l2.cpp

/*
 * ViSP, open source Visual Servoing Platform software.
 * Copyright (C) 2005 - 2025 by Inria. All rights reserved.
 *
 * This software is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 * See the file LICENSE.txt at the root directory of this source
 * distribution for additional information about the GNU GPL.
 *
 * For using ViSP with software that can not be combined with the GNU
 * GPL, please contact Inria about acquiring a ViSP Professional
 * Edition License.
 *
 * See https://visp.inria.fr for more information.
 *
 * This software was developed at:
 * Inria Rennes - Bretagne Atlantique
 * Campus Universitaire de Beaulieu
 * 35042 Rennes Cedex
 * France
 *
 * If you have questions regarding the use of this file, please contact
 * Inria at visp@inria.fr
 *
 * This file is provided AS IS with NO WARRANTY OF ANY KIND, INCLUDING THE
 * WARRANTY OF DESIGN, MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
 *
 * Description:
 * Acquire images using 1394 device with cfox (MAC OSX) and display it
 * using GTK or GTK.
 */

 
#include <stdlib.h>
#include <visp3/core/vpConfig.h>
#include <visp3/core/vpDebug.h>
 
#ifdef VISP_HAVE_V4L2
 
#if defined(VISP_HAVE_DISPLAY)
 
#include <visp3/core/vpDisplay.h>
#include <visp3/core/vpImage.h>
#include <visp3/core/vpTime.h>
#include <visp3/gui/vpDisplayFactory.h>
#include <visp3/io/vpImageIo.h>
#include <visp3/io/vpParseArgv.h>
#include <visp3/sensor/vpV4l2Grabber.h>
 
// List of allowed command line options
#define GETOPTARGS "df:i:hn:o:p:s:t:v:x"
 
#ifdef ENABLE_VISP_NAMESPACE
using namespace VISP_NAMESPACE_NAME;
#endif
 
typedef enum
{
  grey_image = 0, // for ViSP unsigned char grey images
  color_image     // for ViSP vpRGBa color images
} vpImage_type;

void usage(const char *name, const char *badparam, unsigned fps, unsigned input, unsigned scale, long niter,
           const std::string &device, vpV4l2Grabber::vpV4l2PixelFormatType pixelformat, const vpImage_type &image_type,
           const std::string &opath)
{
  fprintf(stdout, "\n\
Grab grey level images using the Video For Linux Two framegrabber. \n\
Display these images using X11 or GTK.\n\
\n\
SYNOPSIS\n\
  %s [-v <video device>] [-f <fps=25|50>] \n\
     [-i <input=0|1|2|3> [-s <scale=1|2|4>] [-p <pixel format>]\n\
     [-n <niter>] [-t <image type>] [-o <filename>] [-x] [-d] [-h]\n",
          name);
 
  fprintf(stdout, "\n\
OPTIONS:                                                  Default\n\
  -v <video device>                                         %s\n\
     Video device to access to the camera\n\
\n\
  -f <fps>                                                  %u\n\
     Framerate in term od number of images per second.\n\
     Possible values are 25 (for 25Hz) or 50 (for %%) Hz)\n\
\n\
  -i <input>                                                %u\n\
     Framegrabber active input. Values can be 0, 1, 2, 4\n\
\n\
  -p <pixel format>                                         %d\n\
     Camera pixel format. Values must be in [0-%d]:\n\
       0 for gray format\n\
       1 for RGB24 format\n\
       2 for RGB32 format\n\
       3 for BGR24 format\n\
       4 for YUYV format\n\
\n\
  -t <image type>                                           %d\n\
     Kind of images that are acquired/displayed by ViSP. \n\
     Values must be in [0-1]:\n\
       0 for grey images in unsigned char \n\
       1 for color images in vpRGBa\n\
\n\
  -s <scale>                                                %u\n\
     Framegrabber subsampling factor. \n\
     If 1, full resolution image acquisition.\n\
     If 2, half resolution image acquisition. The \n\
     subsampling is achieved by the hardware.\n\
\n\
  -n <niter>                                                %ld\n\
     Number of images to acquire.\n\
\n\
  -d \n\
     Turn off the display.\n\
\n\
  -x \n\
     Activates the extra verbose mode.\n\
\n\
  -o [%%s] : Filename for image saving.                     \n\
     Example: -o %s\n\
     The %%d is for the image numbering. The format is set \n\
     by the extension of the file (ex .png, .pgm, ...) \n\
                    \n\
  -h \n\
     Print the help.\n\n",
          device.c_str(), fps, input, pixelformat, vpV4l2Grabber::V4L2_MAX_FORMAT - 1, image_type, scale, niter,
          opath.c_str());
 
  if (badparam)
    fprintf(stdout, "\nERROR: Bad parameter [%s]\n", badparam);
}

bool getOptions(int argc, const char **argv, unsigned &fps, unsigned &input, unsigned &scale, bool &display,
                bool &verbose, long &niter, std::string &device, vpV4l2Grabber::vpV4l2PixelFormatType &pixelformat,
                vpImage_type &image_type, bool &save, std::string &opath)
{
  const char *optarg_;
  int c;
  while ((c = vpParseArgv::parse(argc, argv, GETOPTARGS, &optarg_)) > 1) {
 
    switch (c) {
    case 'd':
      display = false;
      break;
    case 'f':
      fps = static_cast<unsigned int>(atoi(optarg_));
      break;
    case 'i':
      input = static_cast<unsigned int>(atoi(optarg_));
      break;
    case 'n':
      niter = atol(optarg_);
      break;
    case 'o':
      save = true;
      opath = optarg_;
      break;
    case 'p':
      pixelformat = (vpV4l2Grabber::vpV4l2PixelFormatType)atoi(optarg_);
      break;
    case 's':
      scale = static_cast<unsigned int>(atoi(optarg_));
      break;
    case 't':
      image_type = (vpImage_type)atoi(optarg_);
      break;
    case 'v':
      device = std::string(optarg_);
      break;
    case 'x':
      verbose = true;
      break;
    case 'h':
      usage(argv[0], nullptr, fps, input, scale, niter, device, pixelformat, image_type, opath);
      return false;
 
    default:
      usage(argv[0], optarg_, fps, input, scale, niter, device, pixelformat, image_type, opath);
      return false;
    }
  }
 
  if ((c == 1) || (c == -1)) {
    // standalone param or error
    usage(argv[0], nullptr, fps, input, scale, niter, device, pixelformat, image_type, opath);
    std::cerr << "ERROR: " << std::endl;
    std::cerr << "  Bad argument " << optarg_ << std::endl << std::endl;
    return false;
  }
 
  return true;
}

int main(int argc, const char **argv)
{
  // We create a display if a display library is available
#if (VISP_CXX_STANDARD >= VISP_CXX_STANDARD_11)
  std::shared_ptr<vpDisplay> display = vpDisplayFactory::createDisplay();
#else
  vpDisplay *display = vpDisplayFactory::allocateDisplay();
#endif
  try {
    unsigned int opt_fps = 25;
    unsigned int opt_input = 0;
    unsigned int opt_scale = 1;
    vpV4l2Grabber::vpV4l2PixelFormatType opt_pixelformat = vpV4l2Grabber::V4L2_YUYV_FORMAT;
    long opt_iter = 100;
    bool opt_verbose = false;
    bool opt_display = true;
    std::string opt_device = "/dev/video0";
    bool opt_save = false;
    // Default output path for image saving
    std::string opt_opath = "/tmp/I%04d.ppm";
 
    vpImage_type opt_image_type = color_image;
 
    // Read the command line options
    if (getOptions(argc, argv, opt_fps, opt_input, opt_scale, opt_display, opt_verbose, opt_iter, opt_device,
                   opt_pixelformat, opt_image_type, opt_save, opt_opath) == false) {
      return EXIT_FAILURE;
    }
 
    // Declare an image, this is a gray level image (unsigned char) and
    // an other one that is a color image. There size is not defined
    // yet. It will be defined when the image will acquired the first
    // time.
    vpImage<unsigned char> Ig; // grey level image
    vpImage<vpRGBa> Ic;        // color image
 
    // Creates the grabber
    vpV4l2Grabber g;
 
    // Initialize the grabber
    g.setVerboseMode(opt_verbose);
    g.setDevice(opt_device);
    g.setInput(opt_input);
    g.setScale(opt_scale);
    g.setPixelFormat(opt_pixelformat);
    if (opt_fps == 25)
      g.setFramerate(vpV4l2Grabber::framerate_25fps);
    else
      g.setFramerate(vpV4l2Grabber::framerate_50fps);
    if (opt_image_type == grey_image) {
      // Open the framegrabber with the specified settings on grey images
      g.open(Ig);
      // Acquire an image
      g.acquire(Ig);
      std::cout << "Grey image size: width : " << Ig.getWidth() << " height: " << Ig.getHeight() << std::endl;
    }
    else {
   // Open the framegrabber with the specified settings on color images
      g.open(Ic);
      // Acquire an image
      g.acquire(Ic);
      std::cout << "Color image size: width : " << Ic.getWidth() << " height: " << Ic.getHeight() << std::endl;
    }
 
    if (opt_display) {
      // Display the image
      // The image class has a member that specify a pointer toward
      // the display that has been initialized in the display declaration
      // therefore is is no longer necessary to make a reference to the
      // display variable.
      if (opt_image_type == grey_image) {
        display->init(Ig, 100, 100, "V4L2 grey images framegrabbing");
        vpDisplay::display(Ig);
        vpDisplay::flush(Ig);
      }
      else {
        display->init(Ic, 100, 100, "V4L2 color images framegrabbing");
        vpDisplay::display(Ic);
        vpDisplay::flush(Ic);
      }
    }
    // Acquisition loop
    long cpt = 1;
    while (cpt++ < opt_iter) {
      // Measure the initial time of an iteration
      double t = vpTime::measureTimeMs();
      // Acquire the image
      if (opt_image_type == grey_image) {
        g.acquire(Ig);
        if (opt_display) {
          // Display the image
          vpDisplay::display(Ig);
          // Flush the display
          vpDisplay::flush(Ig);
        }
      }
      else {
        g.acquire(Ic);
        if (opt_display) {
          // Display the image
          vpDisplay::display(Ic);
          // Flush the display
          vpDisplay::flush(Ic);
        }
      }
 
      if (opt_save) {
        char buf[FILENAME_MAX];
        snprintf(buf, FILENAME_MAX, opt_opath.c_str(), cpt);
        std::string filename(buf);
        std::cout << "Write: " << filename << std::endl;
        if (opt_image_type == grey_image) {
          vpImageIo::write(Ig, filename);
        }
        else {
          vpImageIo::write(Ic, filename);
        }
      }
 
      // Print the iteration duration
      std::cout << "time: " << vpTime::measureTimeMs() - t << " (ms)" << std::endl;
    }
 
    g.close();
#if (VISP_CXX_STANDARD < VISP_CXX_STANDARD_11)
    if (display != nullptr) {
      delete display;
    }
#endif
    return EXIT_SUCCESS;
  }
  catch (const vpException &e) {
    std::cout << "Catch an exception: " << e << std::endl;
#if (VISP_CXX_STANDARD < VISP_CXX_STANDARD_11)
    if (display != nullptr) {
      delete display;
    }
#endif
    return EXIT_FAILURE;
  }
}
#else
int main()
{
  std::cout << "You do not have X11, or GTK functionalities to display images..." << std::endl;
  std::cout << "Tip if you are on a unix-like system:" << std::endl;
  std::cout << "- Install X11, configure again ViSP using cmake and build again this example" << std::endl;
  std::cout << "Tip if you are on a windows-like system:" << std::endl;
  std::cout << "- Install GTK, configure again ViSP using cmake and build again this example" << std::endl;
  return EXIT_SUCCESS;
}
#endif
#else
int main()
{
  std::cout << "You do not have Video 4 Linux 2 functionality enabled" << std::endl;
  std::cout << "Tip if you are on a unix-like system:" << std::endl;
  std::cout << "- Install libv4l2, configure again ViSP using cmake and build again this example" << std::endl;
  return EXIT_SUCCESS;
}
#endif