📅  最后修改于: 2020-12-14 05:41:38             🧑  作者: Mango
Prewitt运算符用于图像中的边缘检测。它检测两种类型的边缘:垂直边缘和水平边缘。
我们使用OpenCV函数filter2D将Prewitt运算符应用于图像。可以在Imgproc软件包下找到。其语法如下-
filter2D(src, dst, depth , kernel, anchor, delta, BORDER_DEFAULT );
函数参数描述如下-
Sr.No. | Argument & Description |
---|---|
1 |
src It is source image. |
2 |
dst It is destination image. |
3 |
depth It is the depth of dst. A negative value (such as -1) indicates that the depth is the same as the source. |
4 |
kernel It is the kernel to be scanned through the image. |
5 |
anchor It is the position of the anchor relative to its kernel. The location Point (-1, -1) indicates the center by default. |
6 |
delta It is a value to be added to each pixel during the convolution. By default it is 0. |
7 |
BORDER_DEFAULT We let this value by default. |
除了filter2D方法之外,Imgproc类还提供其他方法。他们简要描述-
Sr.No. | Method & Description |
---|---|
1 |
cvtColor(Mat src, Mat dst, int code, int dstCn) It converts an image from one color space to another. |
2 |
dilate(Mat src, Mat dst, Mat kernel) It dilates an image by using a specific structuring element. |
3 |
equalizeHist(Mat src, Mat dst) It equalizes the histogram of a grayscale image. |
4 |
filter2D(Mat src, Mat dst, int depth, Mat kernel, Point anchor, double delta) It convolves an image with the kernel. |
5 |
GaussianBlur(Mat src, Mat dst, Size ksize, double sigmaX) It blurs an image using a Gaussian filter. |
6 |
integral(Mat src, Mat sum) It calculates the integral of an image. |
下面的示例演示如何使用Imgproc类将Prewitt运算符应用于灰度图像。
import org.opencv.core.Core;
import org.opencv.core.CvType;
import org.opencv.core.Mat;
import org.opencv.highgui.Highgui;
import org.opencv.imgproc.Imgproc;
public class convolution {
public static void main( String[] args ) {
try {
int kernelSize = 9;
System.loadLibrary( Core.NATIVE_LIBRARY_NAME );
Mat source = Highgui.imread("grayscale.jpg", Highgui.CV_LOAD_IMAGE_GRAYSCALE);
Mat destination = new Mat(source.rows(),source.cols(),source.type());
Mat kernel = new Mat(kernelSize,kernelSize, CvType.CV_32F) {
{
put(0,0,-1);
put(0,1,0);
put(0,2,1);
put(1,0-1);
put(1,1,0);
put(1,2,1);
put(2,0,-1);
put(2,1,0);
put(2,2,1);
}
};
Imgproc.filter2D(source, destination, -1, kernel);
Highgui.imwrite("output.jpg", destination);
} catch (Exception e) {
System.out.println("Error: " + e.getMessage());
}
}
}
当您执行给定的代码时,将看到以下输出-
原始图像与垂直边缘的Prewitt运算符卷积,如下所示-
-1 | 0 | 1 |
-1 | 0 | 1 |
-1 | 0 | 1 |
该原始图像还已经与水平边缘的Prewitt运算符进行了卷积运算,如下所示:
-1 | -1 | -1 |
0 | 0 | 0 |
1 | 1 | 1 |