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copied!<p>getRGB() returns the int representations of a pixel, including the alpha channel. Since a int is 4-byte (32 bits), this int will be like this:</p> <pre><code>01010101 11111111 10101010 11111111 Alpha Red Green Blue </code></pre> <p>When you add the three values, this is using the alpha channel too, so I guess this is making you get strange results. Also, adding ints this way can cause "overflow" in one of the channels. For example, if one pixel has a blue value of 255 and another one has a value of 2, the sum will have a value 1 for green and value 1 for blue.</p> <p>To extract each color channel from the int you can do this. </p> <pre><code>red = (rgb >> 16) & 0xFF; green = (rgb >>8 ) & 0xFF; blue = (rgb) & 0xFF; </code></pre> <p>(This is what Color class does internally inside getRed(), getBlue() and getGreen() <a href="http://grepcode.com/file/repository.grepcode.com/java/root/jdk/openjdk/6-b14/java/awt/Color.java#Color.getRed%28%29" rel="nofollow">http://grepcode.com/file/repository.grepcode.com/java/root/jdk/openjdk/6-b14/java/awt/Color.java#Color.getRed%28%29</a>)</p> <p>Then, combine the colors like this:</p> <pre><code>combinedImage.setRGB(x, y, new Color( ((image1.getRGB(x, y) >> 16 & 0xFF) + (image1.getRGB(x, y) >> 16 & 0xFF) + (image1.getRGB(x, y) >> 16 & 0xFF))/3, ((image1.getRGB(x, y) >> 8 & 0xFF) + (image1.getRGB(x, y) >> 8 & 0xFF) + (image1.getRGB(x, y) >> 8 & 0xFF))/3, ((image1.getRGB(x, y) & 0xFF) + (image1.getRGB(x, y) & 0xFF) + (image1.getRGB(x, y) & 0xFF))/3). getRGB()); </code></pre> <p>Or use <code>new Color(image1.getRGB(x, y)).getRed()</code> each time for each image.</p> <pre><code>combinedImage.setRGB(x, y, new Color( (new Color(image1.getRGB(x, y)).getRed() + new Color(image2.getRGB(x, y)).getRed() + new Color(image3.getRGB(x, y)).getRed())/3, (new Color(image1.getRGB(x, y)).getGreen() + new Color(image2.getRGB(x, y)).getGreen() + new Color(image3.getRGB(x, y)).getGreen())/3, (new Color(image1.getRGB(x, y)).getBlue() + new Color(image2.getRGB(x, y)).getBlue() + new Color(image3.getRGB(x, y)).getBlue())/3). getRGB()); </code></pre>

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