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Generate identicons using java.
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import javax.imageio.ImageIO; | |
import java.awt.geom.AffineTransform; | |
import java.awt.image.AffineTransformOp; | |
import java.awt.image.BufferedImage; | |
import java.awt.image.WritableRaster; | |
import java.io.File; | |
import java.io.IOException; | |
import java.io.UnsupportedEncodingException; | |
import java.security.MessageDigest; | |
import java.security.NoSuchAlgorithmException; | |
/** | |
* Created by grender on 1/07/17. | |
*/ | |
public class IdenticonGenerator { | |
public static BufferedImage generateIdenticons(String text, int image_width, int image_height) { | |
int width = 5, height = 5; | |
byte[] hash = text.getBytes(); | |
BufferedImage identicon = new BufferedImage(width, height, BufferedImage.TYPE_INT_ARGB); | |
WritableRaster raster = identicon.getRaster(); | |
int[] background = new int[] {255,255,255, 0}; | |
int[] foreground = new int[] {hash[0] & 255, hash[1] & 255, hash[2] & 255, 255}; | |
for(int x = 0; x < width; x++) { | |
//Enforce horizontal symmetry | |
int i = x < 3 ? x : 4 - x; | |
for(int y = 0; y < height; y++) { | |
int[] pixelColor; | |
//toggle pixels based on bit being on/off | |
if ((hash[i] >> y & 1) == 1) | |
pixelColor = foreground; | |
else | |
pixelColor = background; | |
raster.setPixel(x, y, pixelColor); | |
} | |
} | |
BufferedImage finalImage = new BufferedImage(image_width, image_height, BufferedImage.TYPE_INT_ARGB); | |
//Scale image to the size you want | |
AffineTransform at = new AffineTransform(); | |
at.scale(image_width / width, image_height / height); | |
AffineTransformOp op = new AffineTransformOp(at, AffineTransformOp.TYPE_NEAREST_NEIGHBOR); | |
finalImage = op.filter(identicon, finalImage); | |
return finalImage; | |
} | |
public static String hex(byte[] array) { | |
StringBuilder sb = new StringBuilder(); | |
for (int i = 0; i < array.length; ++i) { | |
sb.append(Integer.toHexString((array[i] | |
& 0xFF) | 0x100).substring(1,3)); | |
} | |
return sb.toString(); | |
} | |
public static String md5Hex(String message) { | |
try { | |
MessageDigest md = | |
MessageDigest.getInstance("MD5"); | |
return hex (md.digest(message.getBytes("CP1252"))); | |
} catch (NoSuchAlgorithmException | UnsupportedEncodingException e) { | |
e.printStackTrace(); | |
} | |
return null; | |
} | |
public static void saveImage(BufferedImage bufferedImage, String name) { | |
File outputfile = new File(name + ".png"); | |
try { | |
ImageIO.write(bufferedImage, "png", outputfile); | |
} catch (IOException e) { | |
e.printStackTrace(); | |
} | |
} | |
public static void main(String args[]) { | |
if (args.length < 1) { | |
System.out.println("Pass the text as arg"); | |
System.exit(1); | |
} | |
String text = args[0]; | |
String md5 = md5Hex(text.toLowerCase()); | |
saveImage(generateIdenticons(md5, 500, 500), md5); | |
} | |
} |
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