/** * Fills the whole image with the specified pixel value * * @param img An image. * @param value The value that the image is being filled with. */ public static void fill(ImageInt16 img, int value) { final int h = img.getHeight(); final int w = img.getWidth(); short[] data = img.data; for (int y = 0; y < h; y++) { int index = img.getStartIndex() + y * img.getStride(); for (int x = 0; x < w; x++) { data[index++] = (short) value; } } }
/** * Computes the mean squared error (MSE) between the two images. * * @param imgA first image. Not modified. * @param imgB second image. Not modified. * @return error between the two images. */ public static double computeMeanSquaredError(ImageInt16 imgA, ImageInt16 imgB) { final int h = imgA.getHeight(); final int w = imgA.getWidth(); double total = 0; for (int y = 0; y < h; y++) { for (int x = 0; x < w; x++) { double difference = imgA.get(x, y) - imgB.get(x, y); total += difference * difference; } } return total / (w * h); }
/** * Sets each value in the image to a value drawn from an uniform distribution that has a range of * min <= X < max. */ public static void randomize(ImageInt16 img, Random rand, int min, int max) { final int h = img.getHeight(); final int w = img.getWidth(); int range = max - min; short[] data = img.data; for (int y = 0; y < h; y++) { int index = img.getStartIndex() + y * img.getStride(); for (int x = 0; x < w; x++) { data[index++] = (short) (rand.nextInt(range) + min); } } }