Bitmap转为本地URL并存在Card && 本地URL转Bitmap

附各种转换：

http://glblong.blog.51cto.com/3058613/1304090

这里要申明权限：

<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />

bitmap转本地URL：

	public static String getSDPath() {
		File sdDir = null;
		boolean sdCardExist = Environment.getExternalStorageState().equals(android.os.Environment.MEDIA_MOUNTED); 
        // 判断sd卡是否存在
		if (sdCardExist) {
			sdDir = Environment.getExternalStorageDirectory();// 获取跟目录
		}
		return sdDir.toString();
	}

	/**
	 * 保存文件
	 * 
	 * @param bm
	 * @param fileName
	 * @throws IOException
	 */
	public void saveFile(Bitmap bm, String fileName) throws IOException {
        //获得路径
		String path = getSDPath() + "/revoeye/";
		File dirFile = new File(path);
		if (!dirFile.exists()) {
			dirFile.mkdirs();//保存路径
		}
		// 这里最好不要保存的名字都一样，容易出现imageLoader缓存的问题
        //path + fileName + ".jpg" 就是本地的URL
		File myCaptureFile = new File(path + fileName + ".jpg");
		if(myCaptureFile.exists()){
			myCaptureFile.delete();
		}
		myCaptureFile.createNewFile();
		BufferedOutputStream bos = new BufferedOutputStream(new FileOutputStream(myCaptureFile));
		bm.compress(Bitmap.CompressFormat.JPEG, 80, bos);
		bos.flush();
		bos.close();
	}

本地URL转Bitmap：

    /**缩小图片到width和height的范围内
	 * 
	 * @param path 图片的位置
	 * @param width 宽度
	 * @param height 高度
	 * @return
	 */
	public static Bitmap resizePhoto(String path, int width, int height) {
		BufferedInputStream in = null;
		try {
			in = new BufferedInputStream(new FileInputStream(new File(path)));
			BitmapFactory.Options options = new BitmapFactory.Options();
			options.inJustDecodeBounds = true;
			BitmapFactory.decodeStream(in, null, options);
			int i = 0;
			Bitmap bitmap = null;
			while (true) {
				if ((options.outWidth >> i <= width) && (options.outHeight >> i <= height)) {
					in = new BufferedInputStream(new FileInputStream(new File(path)));
					options.inSampleSize = (int) Math.pow(2.0D, i);
					options.inJustDecodeBounds = false;
					bitmap = BitmapFactory.decodeStream(in, null, options);
					break;
				}
				i += 1;
			}
			return bitmap;
		} catch (FileNotFoundException e) {
			e.printStackTrace();
		} finally {
			try {
				if (in != null) {
					in.close();
				}
			} catch (Exception e) {
				// ignore
			}
		}
		return null;
	}

来自为知笔记(Wiz)

Bitmap转为本地URL并存在Card && 本地URL转Bitmap