Sunday, 29 December 2013

Android make Image Sharper | Android image Blur Issue

Hello Droid Guys,
    Today , I am going to share a sample code which helps you in making image
more sharper and clear also helps you in fixing image Blur issue .This is based on
Convolution Matrix Theorem.

About Convolution Matrix : Check this link

Image Before:


Image After :


 1. ImageHelper.java : This is our helper class which helps in processing image
     sharper/


package com.exampl.imagerun;

import android.graphics.Bitmap;
import android.graphics.Color;
 
public class ImageHelper
{
    public static final int SIZE = 3;
 
    public double[][] Matrix;
    public double Factor = 1;
    public double Offset = 1;
 
   //Constructor with argument of size
    public ImageHelper(int size) {
        Matrix = new double[size][size];
    }
 
    public void setAll(double value) {
        for (int x = 0; x < SIZE; ++x) {
            for (int y = 0; y < SIZE; ++y) {
                Matrix[x][y] = value;
            }
        }
    }
 
    public void applyConfig(double[][] config) {
        for(int x = 0; x < SIZE; ++x) {
            for(int y = 0; y < SIZE; ++y) {
                Matrix[x][y] = config[x][y];
            }
        }
    }
 
    public static Bitmap computeConvolution3x3(Bitmap src, ImageHelper matrix) {
        int width = src.getWidth();
        int height = src.getHeight();
        Bitmap result = Bitmap.createBitmap(width, height, src.getConfig());
 
        int A, R, G, B;
        int sumR, sumG, sumB;
        int[][] pixels = new int[SIZE][SIZE];
 
        for(int y = 0; y < height - 2; ++y) {
            for(int x = 0; x < width - 2; ++x) {
 
                // get pixel matrix
                for(int i = 0; i < SIZE; ++i) {
                    for(int j = 0; j < SIZE; ++j) {
                        pixels[i][j] = src.getPixel(x + i, y + j);
                    }
                }
 
                // get alpha of center pixel
                A = Color.alpha(pixels[1][1]);
 
                // init color sum
                sumR = sumG = sumB = 0;
 
                // get sum of RGB on matrix
                for(int i = 0; i < SIZE; ++i) {
                    for(int j = 0; j < SIZE; ++j) {
                        sumR += (Color.red(pixels[i][j]) * matrix.Matrix[i][j]);
                        sumG += (Color.green(pixels[i][j]) * matrix.Matrix[i][j]);
                        sumB += (Color.blue(pixels[i][j]) * matrix.Matrix[i][j]);
                    }
                }
 
                // get final Red
                R = (int)(sumR / matrix.Factor + matrix.Offset);
                if(R < 0) { R = 0; }
                else if(R > 255) { R = 255; }
 
                // get final Green
                G = (int)(sumG / matrix.Factor + matrix.Offset);
                if(G < 0) { G = 0; }
                else if(G > 255) { G = 255; }
 
                // get final Blue
                B = (int)(sumB / matrix.Factor + matrix.Offset);
                if(B < 0) { B = 0; }
                else if(B > 255) { B = 255; }
 
                // apply new pixel
                result.setPixel(x + 1, y + 1, Color.argb(A, R, G, B));
            }
        }
 
        // final image
        return result;
    }
}

 Now, In our Activity class we need to add following code:

ImageView imageView=(ImageView)findViewById(R.id.image);


Now set image on image view

image.setImageBitmap(sharpenImage(BitmapFactory.

decodeResource(getResources(),images[i]),12));

And, here we are using Convolution Matrix Theorem to make image sharper.

 public Bitmap sharpenImage(Bitmap src, double weight) {
    // set sharpness configuration
    double[][] SharpConfig = new double[][] { { 0, -2, 0 },
    { -2, weight, -2 }, { 0, -2, 0 } };
    // create convolution matrix instance
    ImageHelper convMatrix = new ImageHelper(3);
    // apply configuration
    convMatrix.applyConfig(SharpConfig);
    // set weight according to factor
    convMatrix.Factor = weight - 8;
    return ImageHelper.computeConvolution3x3(src, convMatrix);
 }


Hope this will help some one.
Enjoy Coding :)

Mukesh Yadav

Hi Guys I am from Delhi working as Web/Mobile Application Developer(Android Developer), also have knowledge of Roboelctric and Mockito ,android test driven development... Blogging has been my passion and I think blogging is one of the powerful medium to share knowledge and ideas....

1 comments:

  1. Hi Mukesh Yadav, this blog help me a lot. Thank you.
    Regards
    Murali.

    ReplyDelete

 

Copyright @ 2013 Android Developer Blog.

Blog Widget by LinkWithin