/** Adds Gaussian/normal i.i.d noise to each pixel in the image. */
public static void addGaussian(ImageSInt8 img, Random rand, double sigma, int min, int max) {
final int h = img.getHeight();
final int w = img.getWidth();
byte[] data = img.data;
for (int y = 0; y < h; y++) {
int index = img.getStartIndex() + y * img.getStride();
for (int x = 0; x < w; x++) {
int value = (data[index]) + (int) (rand.nextGaussian() * sigma);
if (value < min) value = min;
if (value > max) value = max;
data[index++] = (byte) value;
}
}
}
/** Adds uniform i.i.d noise to each pixel in the image. Noise range is min <= X < max. */
public static void addUniform(ImageSInt8 img, Random rand, int min, int max) {
final int h = img.getHeight();
final int w = img.getWidth();
int range = max - min;
byte[] data = img.data;
for (int y = 0; y < h; y++) {
int index = img.getStartIndex() + y * img.getStride();
for (int x = 0; x < w; x++) {
int value = (data[index]) + rand.nextInt(range) + min;
if (value < -128) value = -128;
if (value > 127) value = 127;
data[index++] = (byte) value;
}
}
}