Visual Servoing Platform  version 3.6.1 under development (2023-11-30)
#include <visp3/core/vpTime.h>
#include <visp3/gui/vpDisplayGDI.h>
#include <visp3/gui/vpDisplayGTK.h>
#include <visp3/gui/vpDisplayOpenCV.h>
#include <visp3/gui/vpDisplayX.h>
#include <visp3/io/vpVideoWriter.h>
#include <visp3/sensor/vpV4l2Grabber.h>
#include <opencv2/videoio.hpp>
int main(int argc, const char *argv [])
#if ((defined(VISP_HAVE_V4L2) || defined(HAVE_OPENCV_VIDEOIO)) && \
(defined(VISP_HAVE_X11) || defined(VISP_HAVE_GDI) || defined(HAVE_OPENCV_HIGHGUI) || defined(VISP_HAVE_GTK)))
std::string opt_videoname = "video-recorded.mpg";
int opt_device = 0;
for (int i = 0; i < argc; i++) {
if (std::string(argv[i]) == "--device")
opt_device = atoi(argv[i + 1]);
else if (std::string(argv[i]) == "--name")
opt_videoname = std::string(argv[i + 1]);
else if (std::string(argv[i]) == "--help" || std::string(argv[i]) == "-h") {
std::cout << "\nUsage: " << argv[0] << " [--device <device number>] [--name <video name>] [--help][-h]\n"
<< std::endl;
std::cout << "Use device: " << opt_device << std::endl;
std::cout << "Record video in: " << opt_videoname << std::endl;
try {
// vpImage<vpRGBa> I; // for color images
vpImage<unsigned char> I; // for gray images
#if defined(VISP_HAVE_V4L2)
std::ostringstream device;
device << "/dev/video" << opt_device;
g.setScale(1); // Acquire full resolution images;
#elif defined(HAVE_OPENCV_VIDEOIO)
cv::VideoCapture g(opt_device);
if (!g.isOpened()) { // check if we succeeded
std::cout << "Failed to open the camera" << std::endl;
cv::Mat frame;
g >> frame; // get a new frame from camera
std::cout << "Image size: " << I.getWidth() << " " << I.getHeight() << std::endl;
#if defined(VISP_HAVE_X11)
#elif defined(VISP_HAVE_GDI)
#elif defined(HAVE_OPENCV_HIGHGUI)
#elif defined(VISP_HAVE_GTK)
d.init(I, 0, 0, "Camera view");
vpVideoWriter writer;
#if (VISP_HAVE_OPENCV_VERSION >= 0x030000)
writer.setCodec(cv::VideoWriter::fourcc('P', 'I', 'M', '1')); // MPEG-1 codec
writer.setCodec(CV_FOURCC('P', 'I', 'M', '1'));
bool recording = false;
for (;;) {
#if defined(VISP_HAVE_V4L2)
#elif defined(HAVE_OPENCV_VIDEOIO)
g >> frame;
if (recording == false) {
vpDisplay::displayText(I, 10, 10, "A click to start recording", vpColor::green);
if (vpDisplay::getClick(I, false))
recording = true;
else {
vpDisplay::displayText(I, 10, 10, "Recording: A click to stop and exit", vpColor::red);
if (vpDisplay::getClick(I, false))
std::cout << "The video was recorded in \"" << opt_videoname << "\"" << std::endl;
catch (const vpException &e) {
std::cout << "Catch an exception: " << e << std::endl;
std::cout << "Install OpenCV and rebuild ViSP to use this example." << std::endl;
static const vpColor red
Definition: vpColor.h:211
static const vpColor green
Definition: vpColor.h:214
Display for windows using GDI (available on any windows 32 platform).
Definition: vpDisplayGDI.h:128
The vpDisplayGTK allows to display image using the GTK 3rd party library. Thus to enable this class G...
Definition: vpDisplayGTK.h:128
The vpDisplayOpenCV allows to display image using the OpenCV library. Thus to enable this class OpenC...
Use the X11 console to display images on unix-like OS. Thus to enable this class X11 should be instal...
Definition: vpDisplayX.h:128
void init(vpImage< unsigned char > &I, int win_x=-1, int win_y=-1, const std::string &win_title="") override
static bool getClick(const vpImage< unsigned char > &I, bool blocking=true)
static void display(const vpImage< unsigned char > &I)
static void flush(const vpImage< unsigned char > &I)
static void displayText(const vpImage< unsigned char > &I, const vpImagePoint &ip, const std::string &s, const vpColor &color)
error that can be emitted by ViSP classes.
Definition: vpException.h:59
static void convert(const vpImage< unsigned char > &src, vpImage< vpRGBa > &dest)
unsigned int getWidth() const
Definition: vpImage.h:240
unsigned int getHeight() const
Definition: vpImage.h:182
Class that is a wrapper over the Video4Linux2 (V4L2) driver.
void open(vpImage< unsigned char > &I)
void setScale(unsigned scale=vpV4l2Grabber::DEFAULT_SCALE)
void setDevice(const std::string &devname)
void acquire(vpImage< unsigned char > &I)
Class that enables to write easily a video file or a sequence of images.
void saveFrame(vpImage< vpRGBa > &I)
void setFileName(const std::string &filename)
void open(vpImage< vpRGBa > &I)
void setCodec(const int fourcc_codec)