public static void main(String[] args) {
try {
System.loadLibrary(Core.NATIVE_LIBRARY_NAME);
Mat source = Imgcodecs.imread("test_image.jpg", 0);
Mat destination = new Mat(source.rows(), source.cols(), source.type());
Imgproc.GaussianBlur(source, source, new Size(45, 45), 0);
Imgproc.adaptiveThreshold(
source, source, 255, Imgproc.ADAPTIVE_THRESH_MEAN_C, Imgproc.THRESH_BINARY, 75, 10);
Core.bitwise_not(source, source);
// Line detection
Mat img2 = null;
Imgproc.cvtColor(source, img2, Imgproc.COLOR_GRAY2RGB);
Mat img3 = null;
Imgproc.cvtColor(source, img3, Imgproc.COLOR_GRAY2RGB);
MatOfInt4 lines = new MatOfInt4();
// Imgproc.HoughLines(img, lines, rho, theta, threshold);
// Write to File
Imgcodecs.imwrite("gaussian.jpg", source);
System.out.println("Success!");
} catch (Exception e) {
System.out.println("Error has occurred: " + e.getMessage());
}
}
private ArrayList<Double> applyThresholdOnImage(Mat srcImgMat, Mat outputImgMat) {
double localThreshold;
int startRow;
int endRow;
int startCol;
int endCol;
ArrayList<Double> localThresholds = new ArrayList<Double>();
int numberOfTiles = mPreference.getNumberOfTiles();
int tileWidth = (int) srcImgMat.size().height / numberOfTiles;
int tileHeight = (int) srcImgMat.size().width / numberOfTiles;
// Split image into tiles and apply threshold on each image tile separately.
// process image tiles other than the last one.
for (int tileRowCount = 0; tileRowCount < numberOfTiles; tileRowCount++) {
startRow = tileRowCount * tileWidth;
if (tileRowCount < numberOfTiles - 1) endRow = (tileRowCount + 1) * tileWidth;
else endRow = (int) srcImgMat.size().height;
for (int tileColCount = 0; tileColCount < numberOfTiles; tileColCount++) {
startCol = tileColCount * tileHeight;
if (tileColCount < numberOfTiles - 1) endCol = (tileColCount + 1) * tileHeight;
else endCol = (int) srcImgMat.size().width;
Mat tileThreshold = new Mat();
Mat tileMat = srcImgMat.submat(startRow, endRow, startCol, endCol);
// localThreshold = Imgproc.threshold(tileMat, tileThreshold, 0, 255, Imgproc.THRESH_BINARY
// | Imgproc.THRESH_OTSU);
// RNM: Adaptive threshold rules!
localThreshold = 0x80;
Imgproc.adaptiveThreshold(
tileMat,
tileThreshold,
255,
Imgproc.ADAPTIVE_THRESH_GAUSSIAN_C,
Imgproc.THRESH_BINARY,
91,
2);
Mat copyMat = outputImgMat.submat(startRow, endRow, startCol, endCol);
tileThreshold.copyTo(copyMat);
tileThreshold.release();
localThresholds.add(localThreshold);
}
}
return localThresholds;
}