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<TITLE>Filtering the RGB Values in an Image
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  <h3>
    e669.  
    Filtering the RGB Values in an Image</h3>

This example demonstrates how to create a filter that can modify
any of the RGB pixel values in an image. 


<pre>
    // This filter removes all but the red values in an image
    class GetRedFilter extends RGBImageFilter {
        public GetRedFilter() {
            // When this is set to true, the filter will work with images
            // whose pixels are indices into a color table (<code>IndexColorModel</code>).
            // In such a case, the color values in the color table are filtered.
            canFilterIndexColorModel = true;
        }
    
        // This method is called for every pixel in the image
        public int filterRGB(int x, int y, int rgb) {
            if (x == -1) {
                // The pixel value is from the image's color table rather than the image itself
            }
            // Return only the red component
            return rgb &amp; 0xffff0000;
        }
    }
</pre>
Here's some code that uses the filter:

<pre>
    // Get image
    Image image = new ImageIcon(<font color="#0066ff"><i>"image.gif"</i></font>).getImage();
    
    // Create the filter
    ImageFilter filter = new GetRedFilter();
    FilteredImageSource filteredSrc = new FilteredImageSource(image.getSource(), filter);
    
    // Create the filtered image
    image = Toolkit.getDefaultToolkit().createImage(filteredSrc);
</pre>
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            &nbsp;Related Examples
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e664. <a class="eglink" href="Mandelbrot.html?l=rel">
    Creating an Image from an Array of Color-Indexed Pixel Values
</a>
<br>

e665. <a class="eglink" href="HasAlpha.html?l=rel">
    Determining If an Image Has Transparent Pixels
</a>
<br>

e666. <a class="eglink" href="GetColorModel.html?l=rel">
    Getting the Color Model of an Image
</a>
<br>

e667. <a class="eglink" href="GetGifColors.html?l=rel">
    Getting the Transparent Pixel and Number of Colors Used in a GIF Image
</a>
<br>

e668. <a class="eglink" href="CropImage.html?l=rel">
    Getting a Sub-Image of an Image
</a>
<br>


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        See also: 
<a class="eglink" href="/egs/java.awt.image/pkg.html?l=rel#Buffered%20Images">
    Buffered Images
</a>&nbsp;&nbsp;

<a class="eglink" href="/egs/java.awt.image/pkg.html?l=rel#Effects">
    Effects
</a>&nbsp;&nbsp;

<a class="eglink" href="/egs/java.awt.image/pkg.html?l=rel#Volatile%20Images">
    Volatile Images
</a>&nbsp;&nbsp;

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