Android 图片的压缩

/**
 * TODO filePath:图片路径
 */
public Bitmap compressToBitmap(String filePath) {
    final BitmapFactory.Options options = new BitmapFactory.Options();
    options.inJustDecodeBounds = true;
    BitmapFactory.decodeFile(filePath, options);
    options.inSampleSize = calculateInSampleSize(options, lastUploadImgInfo.maxWidth,lastUploadImgInfo.maxWidth);
    options.inJustDecodeBounds = false;
　　 return BitmapFactory.decodeFile(filePath, options);
}

/**
*
*  计算采样率
*/

public int calculateInSampleSize(BitmapFactory.Options options, int reqWidth, int reqHeight) {

    final int height = options.outHeight;
    final int width = options.outWidth;
    int inSampleSize = 1;
    if (height > reqHeight || width > reqWidth) {

        // Calculate ratios of height and width to requested height and
        // width
        final int heightRatio = Math.round((float) height / (float) reqHeight);
        final int widthRatio = Math.round((float) width / (float) reqWidth);

        inSampleSize = heightRatio > widthRatio ? heightRatio : widthRatio;
    }
    return inSampleSize;
}

/**
* 获取图片旋转角度
*/

public static int getDegree(String path) {
    int degree = 0;
    try {
        ExifInterface exifInterface = new ExifInterface(path);
        int orientation = exifInterface.getAttributeInt(
                ExifInterface.TAG_ORIENTATION,
                ExifInterface.ORIENTATION_NORMAL);
        switch (orientation) {
            case ExifInterface.ORIENTATION_ROTATE_90:
                degree = 90;
                break;
            case ExifInterface.ORIENTATION_ROTATE_180:
                degree = 180;
                break;
            case ExifInterface.ORIENTATION_ROTATE_270:
                degree = 270;
                break;
        }
    } catch (IOException e) {
        e.printStackTrace();
    }
    return degree;
}

/**
 * 将图片纠正到正确方向
 *
 * @param degree ： 图片被系统旋转的角度
 * @param bitmap ： 需纠正方向的图片
 * @return 纠向后的图片
 */
public static Bitmap rotateBitmap(int degree, Bitmap bitmap) {
    Matrix matrix = new Matrix();
    matrix.postRotate(degree);

    Bitmap bm = Bitmap.createBitmap(bitmap, 0, 0, bitmap.getWidth(),
            bitmap.getHeight(), matrix, true);
    return bm;
}