Pixel Functions

There are several functions available on ImmutableImage that operate at the pixel level.

To return all pixels in an image, we can use image.argb() or image.pixels(). The former returns pixels as ARGB integer encodings, and the latter returns them as Pixel objects.

image.pixel(x,y) returns the pixel at the given coordinates and count() returns the total number of pixels in the image.

If we want to count the number of pixels that satisfy a predicate, we can use the version of count that accepts a function.

// count number of pixels with some blue
image.count(pixel -> pixel.blue() > 0)

If you wish to run a side-effecting function for every pixel, then use forEach.

image.forEach(pixel -> {
  if (pixel.blue() == 255) {
    System.out.println("Is totally blue man!");
  }
});

If you want to return a new image, mapping each pixel to another colour, then use map.

// remove all blue
image.map(pixel -> new RGBColor(pixel.red(), pixel.green(), 0).awt());

If you wish to check an image to see if at least one pixel satisfies a predicate, then use exists.

// returns true if any pixel has some blue
image.exists(pixel -> pixel.blue() > 0);

If you wish to run a predicate against every pixel, and return true if all pixels satisfy that predicate, then use forAll.

// returns true if all pixels have some blue
image.forAll(pixel -> pixel.blue() > 0);