grabv4l.cc

torch tracking code, it is a good code

const char *help = "\
progname: grabv4l.cc\n\
code2html: This program grabs images using the V4L interface.\n\
version: Torch3 vision2.0, 2003-2005\n\
(c) Sebastien Marcel ([e-mail])\n";

#include "VideoGrabberV4L.h"
#include "ImageRgb.h"
#include "MTimer.h"
#include "CmdLine.h"

using namespace Torch;

int main(int argc, char **argv)
{
	int device;
	int width;
	int height;
	int n;
	char *input_format;
	bool verbose;
	bool saveppm;

	// Construct the command line
  	CmdLine cmd;
	cmd.setBOption("write log", false);
	
  	// Put the help line at the beginning
  	cmd.info(help);

  	cmd.addText("\nArguments:");
  	cmd.addICmdArg("device", &device, "device");
  	cmd.addText("\nOptions:");
  	cmd.addICmdOption("-width", &width, 384, "width");
  	cmd.addICmdOption("-height", &height, 288, "height");
  	cmd.addBCmdOption("-verbose", &verbose, false, "verbose");
  	cmd.addBCmdOption("-ppm", &saveppm, false, "save frames as ppm");
  	cmd.addSCmdOption("-ifmt", &input_format, "YUV420P", "YUV420 planar");
  	cmd.addICmdOption("-n", &n, 10, "number of frames to gran");

	cmd.read(argc, argv);

	ImageRgb *image = NULL; 
	VideoGrabber *video = NULL;
	VirtualPixmap *currentFrame = NULL;

	//
	image = new ImageRgb(width, height);
	
	//
	char devname[40];
	char imagename[40];
	sprintf(devname, "/dev/video%d", device);

	int videochannel = 3;

	video = new VideoGrabberV4L(devname, width, height, "RGB24", input_format, -1, videochannel, 30, verbose);

	if(video->isOk())
	{
		if(video->initVideoSource())
		{
			print("Video source initialized.\n");

			if(video->openVideoSource())
			{
				print("Video source opened.\n");

				MTimer timer;

				timer.reset();

				for(int i = 0 ; i < n ; i++)
				{
					if(verbose) print(":");
					currentFrame = video->getframe();
					if(verbose) print(".");

					if(saveppm)
					{
						image->copyFrom(width, height, (unsigned char *) currentFrame->getpixmap(), "rgb");

						sprintf(imagename, "frame%02d.ppm", i);
						image->save(imagename);
					}

					video->releaseframe(currentFrame);
				}

				timer.stop();

				if(verbose) print("\n");

				print(" %d frames captured in %02dh %02dm %02ds %02dms %02dus %02dns\n", n, timer.hours, timer.minutes, timer.seconds, timer.mseconds, timer.useconds, timer.nseconds);
			}
				
			video->closeVideoSource();
			print("Video source closed.\n");
		}
	}
	   
	delete video;
	delete image;

	return 0;
}