Can we find which color is dominant in an image using Java, ImageMagick, or JMagick?
in java iterate on each pixel and determine color
import java.awt.image.BufferedImage;
import java.io.File;
import java.util.Collections;
import java.util.Comparator;
import java.util.HashMap;
import java.util.Iterator;
import java.util.LinkedList;
import java.util.List;
import java.util.Map;
import javax.imageio.ImageIO;
import javax.imageio.ImageReader;
import javax.imageio.stream.ImageInputStream;
public class ImageTester {
public static void main(String args[]) throws Exception {
File file = new File("C:\\Users\\Andrew\\Desktop\\myImage.gif");
ImageInputStream is = ImageIO.createImageInputStream(file);
Iterator iter = ImageIO.getImageReaders(is);
if (!iter.hasNext())
{
System.out.println("Cannot load the specified file "+ file);
System.exit(1);
}
ImageReader imageReader = (ImageReader)iter.next();
imageReader.setInput(is);
BufferedImage image = imageReader.read(0);
int height = image.getHeight();
int width = image.getWidth();
Map m = new HashMap();
for(int i=0; i < width ; i++)
{
for(int j=0; j < height ; j++)
{
int rgb = image.getRGB(i, j);
int[] rgbArr = getRGBArr(rgb);
// Filter out grays....
if (!isGray(rgbArr)) {
Integer counter = (Integer) m.get(rgb);
if (counter == null)
counter = 0;
counter++;
m.put(rgb, counter);
}
}
}
String colourHex = getMostCommonColour(m);
System.out.println(colourHex);
}
public static String getMostCommonColour(Map map) {
List list = new LinkedList(map.entrySet());
Collections.sort(list, new Comparator() {
public int compare(Object o1, Object o2) {
return ((Comparable) ((Map.Entry) (o1)).getValue())
.compareTo(((Map.Entry) (o2)).getValue());
}
});
Map.Entry me = (Map.Entry )list.get(list.size()-1);
int[] rgb= getRGBArr((Integer)me.getKey());
return Integer.toHexString(rgb[0])+" "+Integer.toHexString(rgb[1])+" "+Integer.toHexString(rgb[2]);
}
public static int[] getRGBArr(int pixel) {
int alpha = (pixel >> 24) & 0xff;
int red = (pixel >> 16) & 0xff;
int green = (pixel >> 8) & 0xff;
int blue = (pixel) & 0xff;
return new int[]{red,green,blue};
}
public static boolean isGray(int[] rgbArr) {
int rgDiff = rgbArr[0] - rgbArr[1];
int rbDiff = rgbArr[0] - rgbArr[2];
// Filter out black, white and grays...... (tolerance within 10 pixels)
int tolerance = 10;
if (rgDiff > tolerance || rgDiff < -tolerance)
if (rbDiff > tolerance || rbDiff < -tolerance) {
return false;
}
return true;
}
}