OpenCV仿射轉換

可以使用imgproc類的warpAffine()方法在圖像上執行仿射轉換。 以下是這種方法的語法 -

Imgproc.warpAffine(src, dst, tranformMatrix, size);

該方法接受以下參數 -

  • src - 表示此操作的源(輸入圖像)的Mat對象。
  • dst - 表示此操作的目標(輸出圖像)的Mat對象。
  • tranformMatrix - 表示變換矩陣的Mat對象。
  • size - 表示輸出圖像大小的整數類型變量。

示例

以下程序演示如何對給定圖像應用仿射操作。

package com.yiibai.geometric;

import org.opencv.core.Core;
import org.opencv.core.Mat;
import org.opencv.core.MatOfPoint2f;
import org.opencv.core.Point;
import org.opencv.core.Size;
import org.opencv.imgcodecs.Imgcodecs;
import org.opencv.imgproc.Imgproc;

public class AffineTranslation {
   public static void main(String args[]) {
      // Loading the OpenCV core library
      System.loadLibrary( Core.NATIVE_LIBRARY_NAME );

      // Reading the Image from the file and storing it in to a Matrix object
      String file ="F:/worksp/opencv/images/transform_input.jpg";
      Mat src = Imgcodecs.imread(file);

      //Creating an empty matrix to store the result
      Mat dst = new Mat();

      Point p1 = new Point( 0,0 );
      Point p2 = new Point( src.cols() - 1, 0 );
      Point p3 = new Point( 0, src.rows() - 1 );
      Point p4 = new Point( src.cols()*0.0, src.rows()*0.33 );
      Point p5 = new Point( src.cols()*0.85, src.rows()*0.25 );
      Point p6 = new Point( src.cols()*0.15, src.rows()*0.7 );

      MatOfPoint2f ma1 = new MatOfPoint2f(p1,p2,p3);
      MatOfPoint2f ma2 = new MatOfPoint2f(p4,p5,p6);

      // Creating the transformation matrix
      Mat tranformMatrix = Imgproc.getAffineTransform(ma1,ma2);

      // Creating object of the class Size
      Size size = new Size(src.cols(), src.cols());

      // Applying Wrap Affine
      Imgproc.warpAffine(src, dst, tranformMatrix, size);

      // Writing the image
      Imgcodecs.imwrite("F:/worksp/opencv/images/affinetranslate.jpg", dst);

      System.out.println("Image Processed");
   }
}

假定以下是上述程序中指定的輸入圖像:transform_input.jpgOpenCV仿射轉換

執行上面示例代碼,得到以下結果 -
OpenCV仿射轉換