Question

The process is pretty simple — I want to take an image as input, and compare every pixel in the image against a specified color. Then return the percentage of pixels that match the color.

I’m sure this is very simple to implement, I just need some kind of guidance as to which library to use, whether there are any tutorials on image processing by pixels. I haven’t really found anything and would love any help.

Also, if this is easier in another language, I wouldn’t mind using that either. I’m just most proficient with Java

Answer 1

This is doable with the standard Java BufferedImage class.

File file= new File("tardis.jpg");
BufferedImage image = ImageIO.read(file);
int rgb = image.getRGB(42, 42); 

int red   = (rgb & 0x00ff0000) >> 16;
int green = (rgb & 0x0000ff00) >> 8;
int blue  =  rgb & 0x000000ff;

getHeight() and getWidth() do what you’d expect allowing full scanning. ImageIO is a convenience class for using ImageReaders (and writers).