Colorizing images in Java

Question

I\'m working on some code to colorize an image in Java. Basically what I\'d like to do is something along the lines of GIMP\'s colorize command, so that if I have a Buffered

Answer 1

This works exactly like the Colorize function in GIMP and it preserves the transparency. I've also added a few things like Contrast and Brightness, Hue, Sat, and Luminosity - 0circle0 Google Me --> ' Sprite Creator 3'

import java.awt.Color;
import java.awt.image.BufferedImage;

public class Colorizer
{
    public static final int MAX_COLOR = 256;

    public static final float LUMINANCE_RED = 0.2126f;
    public static final float LUMINANCE_GREEN = 0.7152f;
    public static final float LUMINANCE_BLUE = 0.0722f;

    double hue = 180;
    double saturation = 50;
    double lightness = 0;

    int[] lum_red_lookup;
    int[] lum_green_lookup;
    int[] lum_blue_lookup;

    int[] final_red_lookup;
    int[] final_green_lookup;
    int[] final_blue_lookup;

    public Colorizer()
    {
        doInit();
    }

    public void doHSB(double t_hue, double t_sat, double t_bri, BufferedImage image)
    {
        hue = t_hue;
        saturation = t_sat;
        lightness = t_bri;
        doInit();
        doColorize(image);
    }

    private void doInit()
    {
        lum_red_lookup = new int[MAX_COLOR];
        lum_green_lookup = new int[MAX_COLOR];
        lum_blue_lookup = new int[MAX_COLOR];

        double temp_hue = hue / 360f;
        double temp_sat = saturation / 100f;

        final_red_lookup = new int[MAX_COLOR];
        final_green_lookup = new int[MAX_COLOR];
        final_blue_lookup = new int[MAX_COLOR];

        for (int i = 0; i < MAX_COLOR; ++i)
        {
            lum_red_lookup[i] = (int) (i * LUMINANCE_RED);
            lum_green_lookup[i] = (int) (i * LUMINANCE_GREEN);
            lum_blue_lookup[i] = (int) (i * LUMINANCE_BLUE);

            double temp_light = (double) i / 255f;

            Color color = new Color(Color.HSBtoRGB((float) temp_hue, (float) temp_sat, (float) temp_light));

            final_red_lookup[i] = (int) (color.getRed());
            final_green_lookup[i] = (int) (color.getGreen());
            final_blue_lookup[i] = (int) (color.getBlue());
        }
    }

    public void doColorize(BufferedImage image)
    {
        int height = image.getHeight();
        int width;

        while (height-- != 0)
        {
            width = image.getWidth();

            while (width-- != 0)
            {
                Color color = new Color(image.getRGB(width, height), true);

                int lum = lum_red_lookup[color.getRed()] + lum_green_lookup[color.getGreen()] + lum_blue_lookup[color.getBlue()];

                if (lightness > 0)
                {
                    lum = (int) ((double) lum * (100f - lightness) / 100f);
                    lum += 255f - (100f - lightness) * 255f / 100f;
                }
                else if (lightness < 0)
                {
                    lum = (int) (((double) lum * (lightness + 100f)) / 100f);
                }
                Color final_color = new Color(final_red_lookup[lum], final_green_lookup[lum], final_blue_lookup[lum], color.getAlpha());
                image.setRGB(width, height, final_color.getRGB());
            }
        }
    }

    public BufferedImage changeContrast(BufferedImage inImage, float increasingFactor)
    {
        int w = inImage.getWidth();
        int h = inImage.getHeight();

        BufferedImage outImage = new BufferedImage(w, h, BufferedImage.TYPE_INT_ARGB);
        for (int i = 0; i < w; i++)
        {
            for (int j = 0; j < h; j++)
            {
                Color color = new Color(inImage.getRGB(i, j), true);
                int r, g, b, a;
                float fr, fg, fb;

                r = color.getRed();
                fr = (r - 128) * increasingFactor + 128;
                r = (int) fr;
                r = keep256(r);

                g = color.getGreen();
                fg = (g - 128) * increasingFactor + 128;
                g = (int) fg;
                g = keep256(g);

                b = color.getBlue();
                fb = (b - 128) * increasingFactor + 128;
                b = (int) fb;
                b = keep256(b);

                a = color.getAlpha();

                outImage.setRGB(i, j, new Color(r, g, b, a).getRGB());
            }
        }
        return outImage;
    }

    public BufferedImage changeGreen(BufferedImage inImage, int increasingFactor)
    {
        int w = inImage.getWidth();
        int h = inImage.getHeight();

        BufferedImage outImage = new BufferedImage(w, h, BufferedImage.TYPE_INT_ARGB);

        for (int i = 0; i < w; i++)
        {
            for (int j = 0; j < h; j++)
            {
                Color color = new Color(inImage.getRGB(i, j), true);
                int r, g, b, a;
                r = color.getRed();
                g = keep256(color.getGreen() + increasingFactor);
                b = color.getBlue();
                a = color.getAlpha();

                outImage.setRGB(i, j, new Color(r, g, b, a).getRGB());
            }
        }
        return outImage;
    }

    public BufferedImage changeBlue(BufferedImage inImage, int increasingFactor)
    {
        int w = inImage.getWidth();
        int h = inImage.getHeight();

        BufferedImage outImage = new BufferedImage(w, h, BufferedImage.TYPE_INT_ARGB);

        for (int i = 0; i < w; i++)
        {
            for (int j = 0; j < h; j++)
            {
                Color color = new Color(inImage.getRGB(i, j), true);
                int r, g, b, a;
                r = color.getRed();
                g = color.getGreen();
                b = keep256(color.getBlue() + increasingFactor);
                a = color.getAlpha();

                outImage.setRGB(i, j, new Color(r, g, b, a).getRGB());
            }
        }
        return outImage;
    }

    public BufferedImage changeRed(BufferedImage inImage, int increasingFactor)
    {
        int w = inImage.getWidth();
        int h = inImage.getHeight();

        BufferedImage outImage = new BufferedImage(w, h, BufferedImage.TYPE_INT_ARGB);

        for (int i = 0; i < w; i++)
        {
            for (int j = 0; j < h; j++)
            {
                Color color = new Color(inImage.getRGB(i, j), true);
                int r, g, b, a;
                r = keep256(color.getRed() + increasingFactor);
                g = color.getGreen();
                b = color.getBlue();
                a = color.getAlpha();

                outImage.setRGB(i, j, new Color(r, g, b, a).getRGB());
            }
        }
        return outImage;
    }

    public BufferedImage changeBrightness(BufferedImage inImage, int increasingFactor)
    {
        int w = inImage.getWidth();
        int h = inImage.getHeight();

        BufferedImage outImage = new BufferedImage(w, h, BufferedImage.TYPE_INT_ARGB);

        for (int i = 0; i < w; i++)
        {
            for (int j = 0; j < h; j++)
            {
                Color color = new Color(inImage.getRGB(i, j), true);

                int r, g, b, a;

                r = keep256(color.getRed() + increasingFactor);
                g = keep256(color.getGreen() + increasingFactor);
                b = keep256(color.getBlue() + increasingFactor);
                a = color.getAlpha();

                outImage.setRGB(i, j, new Color(r, g, b, a).getRGB());
            }
        }
        return outImage;
    }

    public int keep256(int i)
    {
        if (i <= 255 && i >= 0)
            return i;
        if (i > 255)
            return 255;
        return 0;
    }
}