Binarize Image in Android

Question

I am developing android app that uses tesseract OCR to scan a text from image,
I heard that binarizing image before performing OCR on it will give better result,
So

Answer 1

Wouldn't be to hard to port this from java to android:

/**
 * Image binarization - Otsu algorithm
 *
 * Author: Bostjan Cigan (http://zerocool.is-a-geek.net)
 *
 */

import java.awt.Color;
import java.awt.image.BufferedImage;
import java.io.File;
import java.io.IOException;
import javax.imageio.ImageIO;

public class OtsuBinarize {

    private static BufferedImage original, grayscale, binarized;

    public static void main(String[] args) throws IOException {

        File original_f = new File(args[0]+".jpg");
        String output_f = args[0]+"_bin";
        original = ImageIO.read(original_f);
        grayscale = toGray(original);
        binarized = binarize(grayscale);
        writeImage(output_f);         

    }

    private static void writeImage(String output) throws IOException {
        File file = new File(output+".jpg");
        ImageIO.write(binarized, "jpg", file);
    }

    // Return histogram of grayscale image
    public static int[] imageHistogram(BufferedImage input) {

        int[] histogram = new int[256];

        for(int i=0; i varMax) {
                varMax = varBetween;
                threshold = i;
            }
        }

        return threshold;

    }

    private static BufferedImage binarize(BufferedImage original) {

        int red;
        int newPixel;

        int threshold = otsuTreshold(original);

        BufferedImage binarized = new BufferedImage(original.getWidth(), original.getHeight(), original.getType());

        for(int i=0; i threshold) {
                    newPixel = 255;
                }
                else {
                    newPixel = 0;
                }
                newPixel = colorToRGB(alpha, newPixel, newPixel, newPixel);
                binarized.setRGB(i, j, newPixel); 

            }
        }

        return binarized;

    }

    // Convert R, G, B, Alpha to standard 8 bit
    private static int colorToRGB(int alpha, int red, int green, int blue) {

        int newPixel = 0;
        newPixel += alpha;
        newPixel = newPixel << 8;
        newPixel += red; newPixel = newPixel << 8;
        newPixel += green; newPixel = newPixel << 8;
        newPixel += blue;

        return newPixel;

    }

}