Converting RGB videos to grayscale in OpenCV
cvtColor Converts an image from one color space to another.
Example
void cvtColor(InputArray src, OutputArray dst, int code, int dstCn=0 )
Parameters
| src | input image: 8-bit unsigned, 16-bit unsigned ( CV_16UC… ), or single-precision floating-point. |
| dst | output image of the same size and depth as src. |
| code | color space conversion code (see the description below). |
| dstCn | number of channels in the destination image; if the parameter is 0, the number of the channels is derived automatically from src and code |
Example
#include <cv.h>
#include <highgui.h>
using namespace std;
using namespace cv;
int main(int, char**)
{
cvNamedWindow("grayImage", CV_WINDOW_AUTOSIZE);
CvCapture* capture = cvCreateFileCapture("video.avi");
IplImage* gray_out;
IplImage* frame;
while(1)
{
frame = cvQueryFrame(capture);
if( !frame ) break;
gray_out = cvCreateImage( cvGetSize(frame), IPL_DEPTH_8U, 1 );
// Converts Image from RGB Gray
cvCvtColor(frame , gray_out, CV_RGB2GRAY);
// displaying gray image
cvShowImage("gray image", gray_out);
char c = cvWaitKey(33);
if( c == 27 ) break;
}
cvReleaseCapture(&capture);
cvDestroyWindow("grayImage");
return 0;
}
