opencv掩膜操作

//////////////////////////////////////////实现掩膜操作的算法
int cols = src.cols*src.channels();
int offsetx = src.channels();
int rows = src.rows;
dst = Mat::zeros(src.size(), src.type());
for (int row = 1; row < (rows - 1); row++)
{
const uchar* prevois = src.ptr<uchar>(row - 1);
const uchar* current = src.ptr<uchar>(row);
const uchar* next = src.ptr<uchar>(row + 1);
uchar* output = dst.ptr<uchar>(row);
//printf("1");
for (int col = offsetx; col < cols; col++)
{
output[col] =saturate_cast<uchar>( 5 * current[col] - (current[col - offsetx] + current[col + offsetx] + prevois[col] + next[col]));
//printf("2");
}
}