android部分圖片處理函數

轉載自：http://terryblog.blog.51cto.com/1764499/791516

public class ImageTool {
 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 需要修改的圖片
     * @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，然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
        // 重新讀入圖片，注意這次要把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);// 創建一個新的和SRC長度寬度一樣的位圖
        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();
    }

}