glitch jpeg file in java

JpegGlitch.java

import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.util.Random;

class JpegGlitch {
        public static void main(String[] args) {
                FileInputStream in = null;
                FileOutputStream out = null;

                if(args.length < 2) {
                        abort("Usage: java JpegGlitch in.jpg out.jpg");
                }

                try {
                        in = new FileInputStream(args[0]);
                        out = new FileOutputStream(args[1]);
                        while(true) {
                                int i = in.read();
                                if(i == -1) break;
                                int r = new Random().nextInt(5) + 1;
                                if(i == 48 && new Random().nextInt(r) == 1) i = new Random().nextInt(10) + 47;
                                out.write(i);
                        }
                } catch(FileNotFoundException e) {
                        abort("Error: " + e.getMessage());
                } catch(IOException e) {
                        abort("Error: " + e.getMessage());
                } finally {
                        try {
                                in.close();
                                out.close();
                        } catch(IOException e) {
                                abort("Error: " + e.getMessage());
                        }
                }
        }
        private static void abort(String message) {
                System.out.println(message);
                System.exit(1);
        }
}