学步园

opencv2中的Mat类，进行图像的裁剪这段代码只把原图切成4块。

具体要切成什么样就看亲咯。

int helloworld(IplImage* img)
{
	//将图像大小限定为可以被4整除的size
	int width = img->width/4;
	int height = img->height/4;
	width *= 4;
	height *=4;

	Mat rgb_mat(img, 0);
	rgb_mat.convertTo(rgb_mat, CV_32F);

	Size mat_size;
	mat_size.height = height/2;
	mat_size.width = width/2;

	//构造四个图像矩阵
	Mat mat_top_left(mat_size, CV_32F); //左上角
 	Mat mat_top_right(mat_size, CV_32F);//右上角
 	Mat mat_bottom_left(mat_size, CV_32F);//左下角
 	Mat mat_bottom_right(mat_size, CV_32F);//右下角

	//把原图分割成四张图
	rgb_mat(Rect(0, 0, mat_size.width, mat_size.height)).convertTo(mat_top_left, mat_top_left.type(), 1, 0); 
	rgb_mat(Rect(mat_size.width, 0, mat_size.width, mat_size.height)).convertTo(mat_top_right, mat_top_right.type(), 1, 0); 
	rgb_mat(Rect(0, mat_size.height, mat_size.width, mat_size.height)).convertTo(mat_bottom_left, mat_bottom_left.type(), 1, 0); 
	rgb_mat(Rect(mat_size.width, mat_size.height, mat_size.width, mat_size.height)).convertTo(mat_bottom_right, mat_bottom_right.type(), 1, 0); 
}