圖片放大縮小，去色，轉換格式，增長水印等

Android中圖片的處理（放大縮小，去色，轉換格式，增長水印等），多張圖片四個方位的圖片合成，改變bitmap大小，圖片去色等功能  

Java代碼 
package com.dzh.operateimage;   
import android.graphics.Bitmap;   
import android.graphics.Bitmap.Config;   
import android.graphics.BitmapFactory;   
import android.graphics.Canvas;   
import android.graphics.ColorMatrix;   
import android.graphics.ColorMatrixColorFilter;   
import android.graphics.Paint;   
import android.graphics.PorterDuff.Mode;   
import android.graphics.PorterDuffXfermode;   
import android.graphics.Rect;   
import android.graphics.RectF;   
import android.graphics.drawable.BitmapDrawable;   
import android.graphics.drawable.Drawable;   
import java.io.ByteArrayOutputStream;   
import java.io.File;   
import java.io.FileNotFoundException;   
import java.io.FileOutputStream;   
import java.io.IOException;   
/**  
* 處理圖片的工具類.  
*/  
public class ImageTools {   
public static final int LEFT = 0;   
public static final int RIGHT = 1;   
public static final int TOP = 3;   
public static final int BOTTOM = 4;   
/** */  
/**  
* 圖片去色,返回灰度圖片  
*   
* @param bmpOriginal 傳入的圖片  
* @return 去色後的圖片  
*/  
public static Bitmap toGrayscale(Bitmap bmpOriginal) {   
int width, height;   
height = bmpOriginal.getHeight();   
width = bmpOriginal.getWidth();   
Bitmap bmpGrayscale = Bitmap.createBitmap(width, height, Bitmap.Config.RGB_565);   
Canvas c = new Canvas(bmpGrayscale);   
Paint paint = new Paint();   
ColorMatrix cm = new ColorMatrix();   
cm.setSaturation(0);   
ColorMatrixColorFilter f = new ColorMatrixColorFilter(cm);   
paint.setColorFilter(f);   
c.drawBitmap(bmpOriginal, 0, 0, paint);   
return bmpGrayscale;   
}   
/** */  
/**  
* 去色同時加圓角  
*   
* @param bmpOriginal 原圖  
* @param pixels 圓角弧度  
* @return 修改後的圖片  
*/  
public static Bitmap toGrayscale(Bitmap bmpOriginal, int pixels) {   
return toRoundCorner(toGrayscale(bmpOriginal), pixels);   
}   
/** */  
/**  
* 把圖片變成圓角  
*   
* @param bitmap 須要修改的圖片  
* @param pixels 圓角的弧度  
* @return 圓角圖片  
*/  
public static Bitmap toRoundCorner(Bitmap bitmap, int pixels) {   
Bitmap output = Bitmap   
.createBitmap(bitmap.getWidth(), bitmap.getHeight(), Config.ARGB_8888);   
Canvas canvas = new Canvas(output);   
final int color = 0xff424242;   
final Paint paint = new Paint();   
final Rect rect = new Rect(0, 0, bitmap.getWidth(), bitmap.getHeight());   
final RectF rectF = new RectF(rect);   
final float roundPx = pixels;   
paint.setAntiAlias(true);   
canvas.drawARGB(0, 0, 0, 0);   
paint.setColor(color);   
canvas.drawRoundRect(rectF, roundPx, roundPx, paint);   
paint.setXfermode(new PorterDuffXfermode(Mode.SRC_IN));   
canvas.drawBitmap(bitmap, rect, rect, paint);   
return output;   
}   
/** */  
/**  
* 使圓角功能支持BitampDrawable  
*   
* @param bitmapDrawable  
* @param pixels  
* @return  
*/  
public static BitmapDrawable toRoundCorner(BitmapDrawable bitmapDrawable, int pixels) {   
Bitmap bitmap = bitmapDrawable.getBitmap();   
bitmapDrawable = new BitmapDrawable(toRoundCorner(bitmap, pixels));   
return bitmapDrawable;   
}   
/**  
* 讀取路徑中的圖片，而後將其轉化爲縮放後的bitmap  
*   
* @param path  
*/  
public static void saveBefore(String path) {   
BitmapFactory.Options options = new BitmapFactory.Options();   
options.inJustDecodeBounds = true;   
// 獲取這個圖片的寬和高   
Bitmap bitmap = BitmapFactory.decodeFile(path, options); // 此時返回bm爲空   
options.inJustDecodeBounds = false;   
// 計算縮放比   
int be = (int)(options.outHeight / (float)200);   
if (be <= 0)   
be = 1;   
options.inSampleSize = 2; // 圖片長寬各縮小二分之一   
// 從新讀入圖片，注意此次要把options.inJustDecodeBounds 設爲 false哦   
bitmap = BitmapFactory.decodeFile(path, options);   
int w = bitmap.getWidth();   
int h = bitmap.getHeight();   
System.out.println(w + " " + h);   
// savePNG_After(bitmap,path);   
saveJPGE_After(bitmap, path);   
}   
/**  
* 保存圖片爲PNG  
*   
* @param bitmap  
* @param name  
*/  
public static void savePNG_After(Bitmap bitmap, String name) {   
File file = new File(name);   
try {   
FileOutputStream out = new FileOutputStream(file);   
if (bitmap.compress(Bitmap.CompressFormat.PNG, 100, out)) {   
out.flush();   
out.close();   
}   
} catch (FileNotFoundException e) {   
e.printStackTrace();   
} catch (IOException e) {   
e.printStackTrace();   
}   
}   
/**  
* 保存圖片爲JPEG  
*   
* @param bitmap  
* @param path  
*/  
public static void saveJPGE_After(Bitmap bitmap, String path) {   
File file = new File(path);   
try {   
FileOutputStream out = new FileOutputStream(file);   
if (bitmap.compress(Bitmap.CompressFormat.JPEG, 100, out)) {   
out.flush();   
out.close();   
}   
} catch (FileNotFoundException e) {   
e.printStackTrace();   
} catch (IOException e) {   
e.printStackTrace();   
}   
}   
/**  
* 水印  
*   
* @param bitmap  
* @return  
*/  
public static Bitmap createBitmapForWatermark(Bitmap src, Bitmap watermark) {   
if (src == null) {   
return null;   
}   
int w = src.getWidth();   
int h = src.getHeight();   
int ww = watermark.getWidth();   
int wh = watermark.getHeight();   
// create the new blank bitmap   
Bitmap newb = Bitmap.createBitmap(w, h, Config.ARGB_8888);// 建立一個新的和SRC長度寬度同樣的位圖   
Canvas cv = new Canvas(newb);   
// draw src into   
cv.drawBitmap(src, 0, 0, null);// 在 0，0座標開始畫入src   
// draw watermark into   
cv.drawBitmap(watermark, w - ww + 5, h - wh + 5, null);// 在src的右下角畫入水印   
// save all clip   
cv.save(Canvas.ALL_SAVE_FLAG);// 保存   
// store   
cv.restore();// 存儲   
return newb;   
}   
/**  
* 圖片合成  
*   
* @return  
*/  
public static Bitmap potoMix(int direction, Bitmap... bitmaps) {   
if (bitmaps.length <= 0) {   
return null;   
}   
if (bitmaps.length == 1) {   
return bitmaps[0];   
}   
Bitmap newBitmap = bitmaps[0];   
// newBitmap = createBitmapForFotoMix(bitmaps[0],bitmaps[1],direction);   
for (int i = 1; i < bitmaps.length; i++) {   
newBitmap = createBitmapForFotoMix(newBitmap, bitmaps[i], direction);   
}   
return newBitmap;   
}   
  
private static Bitmap createBitmapForFotoMix(Bitmap first, Bitmap second, int direction) {   
if (first == null) {   
return null;   
}   
if (second == null) {   
return first;   
}    
int fw = first.getWidth();   
int fh = first.getHeight();   
int sw = second.getWidth();   
int sh = second.getHeight();   
Bitmap newBitmap = null;   
if (direction == LEFT) {   
newBitmap = Bitmap.createBitmap(fw + sw, fh > sh ? fh : sh, Config.ARGB_8888);   
Canvas canvas = new Canvas(newBitmap);   
canvas.drawBitmap(first, sw, 0, null);   
canvas.drawBitmap(second, 0, 0, null);   
} else if (direction == RIGHT) {   
newBitmap = Bitmap.createBitmap(fw + sw, fh > sh ? fh : sh, Config.ARGB_8888);   
Canvas canvas = new Canvas(newBitmap);   
canvas.drawBitmap(first, 0, 0, null);   
canvas.drawBitmap(second, fw, 0, null);   
} else if (direction == TOP) {   
newBitmap = Bitmap.createBitmap(sw > fw ? sw : fw, fh + sh, Config.ARGB_8888);   
Canvas canvas = new Canvas(newBitmap);   
canvas.drawBitmap(first, 0, sh, null);   
canvas.drawBitmap(second, 0, 0, null);   
} else if (direction == BOTTOM) {   
newBitmap = Bitmap.createBitmap(sw > fw ? sw : fw, fh + sh, Config.ARGB_8888);   
Canvas canvas = new Canvas(newBitmap);   
canvas.drawBitmap(first, 0, 0, null);   
canvas.drawBitmap(second, 0, fh, null);   
}   
return newBitmap;   
}   
/**  
* 將Bitmap轉換成指定大小  
* @param bitmap  
* @param width  
* @param height  
* @return  
*/  
public static Bitmap createBitmapBySize(Bitmap bitmap,int width,int height)   
{   
return Bitmap.createScaledBitmap(bitmap, width, height, true);   
}   
/**  
* Drawable 轉 Bitmap  
*   
* @param drawable  
* @return  
*/  
public static Bitmap drawableToBitmapByBD(Drawable drawable) {   
BitmapDrawable bitmapDrawable = (BitmapDrawable)drawable;   
return bitmapDrawable.getBitmap();   
}   
/**  
* Bitmap 轉 Drawable  
*   
* @param bitmap  
* @return  
*/  
public static Drawable bitmapToDrawableByBD(Bitmap bitmap) {   
Drawable drawable = new BitmapDrawable(bitmap);   
return drawable;   
}   
/**  
* byte[] 轉 bitmap  
*   
* @param b  
* @return  
*/  
public static Bitmap bytesToBimap(byte[] b) {   
if (b.length != 0) {   
return BitmapFactory.decodeByteArray(b, 0, b.length);   
} else {   
return null;   
}   
}   
/**  
* bitmap 轉 byte[]  
*   
* @param bm  
* @return  
*/  
public static byte[] bitmapToBytes(Bitmap bm) {   
ByteArrayOutputStream baos = new ByteArrayOutputStream();   
bm.compress(Bitmap.CompressFormat.PNG, 100, baos);   
return baos.toByteArray();   
}   
}