OpenCV的抗扭斜的轮廓

Z时代
2024-01-10
分类：问答

inputImage的OpenCV的抗扭斜的轮廓

ResultImage

我已经能够过滤最大的轮廓图像中检测令牌。

我已经应用了经纱知觉，但它只是在轮廓的边缘裁剪图像，没有别的。

我想要将检测到的令牌从图像的其余部分中裁剪出来，在保持比例的情况下对其进行去偏斜，以便结果图像应该直立，笔直。然后，我将继续寻找令牌中的斑点来检测其中标记的日期。

private Mat processMat(Mat srcMat) { 
    Mat processedMat = new Mat(); 
    Imgproc.cvtColor(srcMat, processedMat, Imgproc.COLOR_BGR2GRAY); 
    Imgproc.GaussianBlur(processedMat, processedMat, new Size(5, 5), 5); 
    Imgproc.threshold(processedMat, processedMat, 127, 255, Imgproc.THRESH_BINARY); 
    List<MatOfPoint> contours = new ArrayList<>(); 
    Mat hierarchy = new Mat(); 
    Imgproc.findContours(processedMat, contours, hierarchy, Imgproc.RETR_EXTERNAL, Imgproc.CHAIN_APPROX_SIMPLE); 
    double maxVal = 0; 
    int maxValIdx = 0; 
    for (int contourIdx = 0; contourIdx < contours.size(); contourIdx++) { 
     double contourArea = Imgproc.contourArea(contours.get(contourIdx)); 
     if (maxVal < contourArea) { 
      maxVal = contourArea; 
      maxValIdx = contourIdx; 
     } 
    } 
    if (!contours.isEmpty()) { 
     Imgproc.drawContours(srcMat, contours, maxValIdx, new Scalar(0,255,0), 3); 
     Rect rect = Imgproc.boundingRect(contours.get(maxValIdx)); 
     Log.e("rect", "" + rect); 
     int top = srcMat.height(); 
     int left = srcMat.width(); 
     int right = 0; 
     int bottom = 0; 
     if(rect.x < left) { 
      left = rect.x; 
     } 
     if(rect.x+rect.width > right){ 
      right = rect.x+rect.width; 
     } 
     if(rect.y < top){ 
      top = rect.y; 
     } 
     if(rect.y+rect.height > bottom){ 
      bottom = rect.y+rect.height; 
     } 
     Point topLeft = new Point(left, top); 
     Point topRight = new Point(right, top); 
     Point bottomRight = new Point(right, bottom); 
     Point bottomLeft = new Point(left, bottom); 
     return warp(srcMat, topLeft, topRight, bottomLeft, bottomRight); 
    } 
    return null; 
} 
Mat warp(Mat inputMat, Point topLeft, Point topRight, Point bottomLeft, Point bottomRight) { 
    int resultWidth = (int)(topRight.x - topLeft.x); 
    int bottomWidth = (int)(bottomRight.x - bottomLeft.x); 
    if(bottomWidth > resultWidth) 
     resultWidth = bottomWidth; 
    int resultHeight = (int)(bottomLeft.y - topLeft.y); 
    int bottomHeight = (int)(bottomRight.y - topRight.y); 
    if (bottomHeight > resultHeight) { 
     resultHeight = bottomHeight; 
    } 
    Mat outputMat = new Mat(resultWidth, resultHeight, CvType.CV_8UC1); 
    List<Point> source = new ArrayList<>(); 
    source.add(topLeft); 
    source.add(topRight); 
    source.add(bottomLeft); 
    source.add(bottomRight); 
    Mat startM = Converters.vector_Point2f_to_Mat(source); 
    Point ocvPOut1 = new Point(0, 0); 
    Point ocvPOut2 = new Point(resultWidth, 0); 
    Point ocvPOut3 = new Point(0, resultHeight); 
    Point ocvPOut4 = new Point(resultWidth, resultHeight); 
    List<Point> dest = new ArrayList<>(); 
    dest.add(ocvPOut1); 
    dest.add(ocvPOut2); 
    dest.add(ocvPOut3); 
    dest.add(ocvPOut4); 
    Mat endM = Converters.vector_Point2f_to_Mat(dest); 
    Mat perspectiveTransform = Imgproc.getPerspectiveTransform(startM, endM); 
    Imgproc.warpPerspective(inputMat, outputMat, perspectiveTransform, new Size(resultWidth, resultHeight)); 
    return outputMat; 
}

更新1

替换此：

 return warp(srcMat, topLeft, topRight, bottomLeft, bottomRight);

这一点：

 return warp(srcMat, topLeft, topRight, bottomRight, bottomLeft);

结果更新1：

更新2

public Mat warp(Mat inputMat, MatOfPoint selectedContour) { 
    MatOfPoint2f new_mat = new MatOfPoint2f(selectedContour.toArray()); 
    MatOfPoint2f approxCurve_temp = new MatOfPoint2f(); 
    int contourSize = (int) selectedContour.total(); 
    Imgproc.approxPolyDP(new_mat, approxCurve_temp, contourSize * 0.05, true); 
    double[] temp_double; 
    temp_double = approxCurve_temp.get(0,0); 
    Point p1 = new Point(temp_double[0], temp_double[1]); 
    temp_double = approxCurve_temp.get(1,0); 
    Point p2 = new Point(temp_double[0], temp_double[1]); 
    temp_double = approxCurve_temp.get(2,0); 
    Point p3 = new Point(temp_double[0], temp_double[1]); 
    temp_double = approxCurve_temp.get(3,0); 
    Point p4 = new Point(temp_double[0], temp_double[1]); 
    List<Point> source = new ArrayList<Point>(); 
    source.add(p1); 
    source.add(p2); 
    source.add(p3); 
    source.add(p4); 
    Mat startM = Converters.vector_Point2f_to_Mat(source); 
    int resultWidth = 846; 
    int resultHeight = 2048; 
    Mat outputMat = new Mat(resultWidth, resultHeight, CvType.CV_8UC4); 
    Point ocvPOut1 = new Point(0, 0); 
    Point ocvPOut2 = new Point(0, resultHeight); 
    Point ocvPOut3 = new Point(resultWidth, resultHeight); 
    Point ocvPOut4 = new Point(resultWidth, 0); 
    List<Point> dest = new ArrayList<Point>(); 
    dest.add(ocvPOut1); 
    dest.add(ocvPOut2); 
    dest.add(ocvPOut3); 
    dest.add(ocvPOut4); 
    Mat endM = Converters.vector_Point2f_to_Mat(dest); 
    Mat perspectiveTransform = Imgproc.getPerspectiveTransform(startM, endM); 
    Imgproc.warpPerspective(inputMat, outputMat, perspectiveTransform, new Size(resultWidth, resultHeight), 
      Imgproc.INTER_CUBIC); 
    return outputMat; 
}

结果更新2：

我已经改变了我的经功能的位和代码附加。然而，合成图像以某种方式在错误的方向上旋转。你能指导我这是做这件事的正确方法吗？

Android设备方向设置为：纵向，输入图像也是纵向。

更新3

我设法通过排序的角落，像这样伸直令牌：

List<Point> source = new ArrayList<Point>(); 
    source.add(p2); 
    source.add(p3); 
    source.add(p4); 
    source.add(p1); 
    Mat startM = Converters.vector_Point2f_to_Mat(source);

结果更新3：

然而，由此产生的图像从左侧裁剪，我不知道如何解决这个问题。如果令牌向右或向左倾斜并且输出图像是笔直的，我已设法拉直输入图像。但是，如果输入图像已经将令牌居中且直线向上。它旋转像这样的令牌，使用相同的代码：

问题更新3：