ImageEffects.java

package com.sailrobotics.posterize;

import android.graphics.Bitmap;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.ColorMatrix;
import android.graphics.ColorMatrixColorFilter;
import android.graphics.Paint;

/**
 * Created by asanthan on 7/24/15.
 */
public class ImageEffects {

    public static Bitmap doInvert(Bitmap src) {
        // create new bitmap with the same settings as source bitmap
        Bitmap resultantBitmap = Bitmap.createBitmap(src.getWidth(), src.getHeight(), src.getConfig());
        // color info
        int A, R, G, B;
        int pixelColor;
        // image size
        int height = src.getHeight();
        int width = src.getWidth();

        // scan through every pixel
        for (int y = 0; y < height; y++)
        {
            for (int x = 0; x < width; x++)
            {
                // get one pixel
                pixelColor = src.getPixel(x, y);
                // saving alpha channel
                A = Color.alpha(pixelColor);
                // inverting byte for each R/G/B channel
                R = 255 - Color.red(pixelColor);
                G = 255 - Color.green(pixelColor);
                B = 255 - Color.blue(pixelColor);
                // set newly-inverted pixel to output image
                resultantBitmap.setPixel(x, y, Color.argb(A, R, G, B));
            }
        }
        return resultantBitmap;
    }



    public static Bitmap doSepia(Bitmap bmpOriginal) {
        ColorMatrix sepiaMatrix =new ColorMatrix();
        float[] sepMat={0.3930000066757202f, 0.7689999938011169f, 0.1889999955892563f, 0, 0, 0.3490000069141388f, 0.6859999895095825f, 0.1679999977350235f, 0, 0, 0.2720000147819519f, 0.5339999794960022f, 0.1309999972581863f, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 1};
        sepiaMatrix.set(sepMat);
        final ColorMatrixColorFilter colorFilter= new ColorMatrixColorFilter(sepiaMatrix);
        Bitmap resultantBitmap = bmpOriginal.copy(Bitmap.Config.ARGB_8888, true);
        Paint paint=new Paint();
        paint.setColorFilter(colorFilter);
        Canvas myCanvas =new Canvas(resultantBitmap);
        myCanvas.drawBitmap(resultantBitmap, 0, 0, paint);
        return resultantBitmap;
    }

    public static Bitmap doGreyscale(Bitmap src) {
        // constant factors
        final double GS_RED = 0.299;
        final double GS_GREEN = 0.587;
        final double GS_BLUE = 0.114;

        // create output bitmap
        Bitmap bmOut = Bitmap.createBitmap(src.getWidth(), src.getHeight(), src.getConfig());
        // pixel information
        int A, R, G, B;
        int pixel;

        // get image size
        int width = src.getWidth();
        int height = src.getHeight();

        // scan through every single pixel
        for(int x = 0; x < width; ++x) {
            for(int y = 0; y < height; ++y) {
                // get one pixel color
                pixel = src.getPixel(x, y);
                // retrieve color of all channels
                A = Color.alpha(pixel);
                R = Color.red(pixel);
                G = Color.green(pixel);
                B = Color.blue(pixel);
                // take conversion up to one single value
                R = G = B = (int)(GS_RED * R + GS_GREEN * G + GS_BLUE * B);
                // set new pixel color to output bitmap
                bmOut.setPixel(x, y, Color.argb(A, R, G, B));
            }
        }

        // return final image
        return bmOut;
    }

    public static Bitmap doColourBoost(Bitmap src, int type, float percent) {
        int width = src.getWidth();
        int height = src.getHeight();
        Bitmap bmOut = Bitmap.createBitmap(width, height, src.getConfig());

        int A, R, G, B;
        int pixel;

        for(int x = 0; x < width; ++x) {
            for(int y = 0; y < height; ++y) {
                pixel = src.getPixel(x, y);
                A = Color.alpha(pixel);
                R = Color.red(pixel);
                G = Color.green(pixel);
                B = Color.blue(pixel);
                if(type == 1) {
                    R = (int)(R * (1 + percent));
                    if(R > 255) R = 255;
                }
                else if(type == 2) {
                    G = (int)(G * (1 + percent));
                    if(G > 255) G = 255;
                }
                else if(type == 3) {
                    B = (int)(B * (1 + percent));
                    if(B > 255) B = 255;
                }
                bmOut.setPixel(x, y, Color.argb(A, R, G, B));
            }
        }
        return bmOut;
    }



}