How to make opencl kernel

See more:

OpenCL

I'm trying to make kernel.cl with opencv

for (i = 0; i < cols; i += 5) {
        for (j = 0; j < rows; j += 5) {
        dx = (int) cvGetReal2D (velx, j, i);
        dy = (int) cvGetReal2D (vely, j, i);
        cvLine (dst_img2, cvPoint (i, j), cvPoint (i + dx, j + dy), CV_RGB (255, 0, 0), 1,
        CV_AA, 0);
        }
    }

data types above code [ int cols,rows,dx,dy IplImage* dst_img2 ]

Parallelizing above code, do I have to redefine opencv functions? (cvGetReal2D, cvLine etc..)
Otherwise, is there any method to use opencv function?