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    <p>As <a href="https://stackoverflow.com/a/12336757/3713">EJP noted</a> the masks are used to filter out the values for one of the color components/channels (Red, Green, Blue). And that's usually what you do with bit shift/masking operations. Everything else you do with the values you get is arithmetics or more advanced math.</p> <p>A color channel's range is 0-255, or 0x00 - 0xFF in hexadecimal values. To reconstruct it, you need to bitshift the components value back to their place. Which can be put together with simple arithmetic addition:</p> <pre><code>// Example values int r = 255; // 0xFF int g = 1; // 0x01 int b = 15; // 0x0F // go back to original form: // A R G B int color = r &lt;&lt; 16; // 0x00.FF.00.00 color += g &lt;&lt; 8; // 0x00.FF.01.00 color += b; // 0x00.FF.01.0F // just add back the alpha if it is going to be full on color = += 255 &lt;&lt; 24; // 0xFF.FF.01.0F </code></pre> <p>If you want to do some interpolation between colors you need to do it for each color component seperately, not all of them together in one integer. In some instances it may also a good idea to change the representation from [0-255] to a decimal one [0.0f-1.0f]:</p> <pre><code>// Darken red value by 50% int color = ...; // some color input int mask = 0xFF; int a = (color &gt;&gt; 24) &amp; mask; int r = (color &gt;&gt; 16) &amp; mask; int g = (color &gt;&gt; 8) &amp; mask; int b = color &amp; mask; // convert to decimal form: float rDecimal = r / 255f; // Let r: 0x66 = 102 =&gt; rDecimal: 0.4 // darken with 50%, basically divide it by two rDecimal = r/2; // rDecimal: 0.2 // Go back to original representation and put it back to r r = (int)(rDecimal * 255); // r: 51 = 0x33 // Put it all back in place color = (a &lt;&lt; 24) + (r &lt;&lt; 16) + (g &lt;&lt; 8) + b; </code></pre> <p>Hope this helps out.</p>
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    1. COIf I wanted to do interpolation of a color and map it on a BufferedImage how would I go about it?
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    2. CO@MasqueradeToday: What kind of interpolation do you have in mind? Have you read the [`BufferedImage`](http://docs.oracle.com/javase/1.4.2/docs/api/java/awt/image/BufferedImage.html) java api page? There are `getRBG()` and `setRBG()` methods in it if you want to start simple. You have to iterate through all pixels `for` all x and y coordinates of the picture.
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    3. COWell written and clear code. Is there any performance gain by converting the representation to decimal?
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