所以我对OpenCV完全陌生,在过去的2-3天里,我已经搜索了很多关于如何在Java和Android工作室中使用OpenCV来执行透视校正并检测位图中最大矩形的问题。根据我的搜索,我做了一些工作,但结果位图不正确。我确定我做了很多错事,所以如果有人帮助我会很棒。
提前感谢您的帮助。
public void onPictureTaken(byte[] data, Camera camera)
{
Bitmap myImage = BitmapFactory.decodeByteArray(data, 0, data.length);
Mat matImage = new Mat(myImage.getHeight(),myImage.getWidth(), CvType.CV_8UC3);
Bitmap myBitmap32 = myImage.copy(Bitmap.Config.ARGB_8888, true);
Utils.bitmapToMat(myBitmap32, matImage);
correctPerspective(matImage);
}
public static void correctPerspective(Mat imgSource)
{
// convert the image to black and white does (8 bit)
Imgproc.Canny(imgSource.clone(), imgSource, 50, 50);
// apply gaussian blur to smoothen lines of dots
Imgproc.GaussianBlur(imgSource, imgSource, new org.opencv.core.Size(5, 5), 5);
// find the contours
List<MatOfPoint> contours = new ArrayList<MatOfPoint>();
Imgproc.findContours(imgSource, contours, new Mat(), Imgproc.RETR_LIST, Imgproc.CHAIN_APPROX_SIMPLE);
double maxArea = -1;
MatOfPoint temp_contour = contours.get(0);
// index 0 for starting
// point
MatOfPoint2f approxCurve = new MatOfPoint2f();
for (int idx = 0; idx < contours.size(); idx++) {
temp_contour = contours.get(idx);
double contourarea = Imgproc.contourArea(temp_contour);
// compare this contour to the previous largest contour found
if (contourarea > maxArea) {
// check if this contour is a square
MatOfPoint2f new_mat = new MatOfPoint2f(temp_contour.toArray());
int contourSize = (int) temp_contour.total();
MatOfPoint2f approxCurve_temp = new MatOfPoint2f();
Imgproc.approxPolyDP(new_mat, approxCurve_temp, contourSize * 0.05, true);
if (approxCurve_temp.total() == 4) {
maxArea = contourarea;
approxCurve = approxCurve_temp;
}
}
}
Imgproc.cvtColor(imgSource, imgSource, Imgproc.COLOR_BayerBG2RGB);
double[] temp_double;
temp_double = approxCurve.get(0, 0);
Point p1 = new Point(temp_double[0], temp_double[1]);
temp_double = approxCurve.get(1, 0);
Point p2 = new Point(temp_double[0], temp_double[1]);
temp_double = approxCurve.get(2, 0);
Point p3 = new Point(temp_double[0], temp_double[1]);
temp_double = approxCurve.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);
Mat result = warp(imgSource, startM);
//Saving into bitmap
Bitmap resultBitmap = Bitmap.createBitmap(result.cols(), result.rows(),Bitmap.Config.ARGB_8888);;
Mat tmp = new Mat (result.cols(), result.rows(), CvType.CV_8U, new Scalar(4));
Imgproc.cvtColor(result, tmp, Imgproc.COLOR_RGB2BGRA);
Utils.matToBitmap(tmp, resultBitmap);
}
public static Mat warp(Mat inputMat, Mat startM)
{
int resultWidth = 1200;
int resultHeight = 680;
Point ocvPOut4 = new Point(0, 0);
Point ocvPOut1 = new Point(0, resultHeight);
Point ocvPOut2 = new Point(resultWidth, resultHeight);
Point ocvPOut3 = new Point(resultWidth, 0);
if (inputMat.height() > inputMat.width())
{
ocvPOut3 = new Point(0, 0);
ocvPOut4 = new Point(0, resultHeight);
ocvPOut1 = new Point(resultWidth, resultHeight);
ocvPOut2 = new Point(resultWidth, 0);
}
Mat outputMat = new Mat(resultWidth, resultHeight, CvType.CV_8UC4);
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;
}