Base64工具类（文件、base64字符串、Bitmap相互转换）

 
 
/**
 * Author : 马占柱
 * E-mail : mazhanzhu_3351@163.com
 * Time   : 2019/5/19 9:30
 * Desc   : Base64工具类
 */
public class Base64Util {
    public static final String TAG = "Base64Util";
    private static final char last2byte = (char) Integer.parseInt("00000011", 2);
    private static final char last4byte = (char) Integer.parseInt("00001111", 2);
    private static final char last6byte = (char) Integer.parseInt("00111111", 2);
    private static final char lead6byte = (char) Integer.parseInt("11111100", 2);
    private static final char lead4byte = (char) Integer.parseInt("11110000", 2);
    private static final char lead2byte = (char) Integer.parseInt("11000000", 2);
    private static final char[] encodeTable = new char[]{'A', 'B', 'C', 'D', 'E', 'F', 'G', 'H', 'I', 'J', 'K', 'L', 'M', 'N', 'O', 'P', 'Q', 'R', 'S', 'T', 'U', 'V', 'W', 'X', 'Y', 'Z', 'a', 'b', 'c', 'd', 'e', 'f', 'g', 'h', 'i', 'j', 'k', 'l', 'm', 'n', 'o', 'p', 'q', 'r', 's', 't', 'u', 'v', 'w', 'x', 'y', 'z', '0', '1', '2', '3', '4', '5', '6', '7', '8', '9', '+', '/'};
    //取到 SDCard/Android/data/你的应用包名/cache/目录，一般存放临时缓存数据
    public static String Mzz_File = BaseApplication.getContext().getExternalCacheDir().getAbsolutePath();
 
    public static void gcBitmap(Bitmap bitmap) {
        if (bitmap != null && !bitmap.isRecycled()) {
            bitmap.recycle(); // 回收图片所占的内存
            bitmap = null;
            System.gc(); // 提醒系统及时回收
        }
    }
 
    /**
     * Bitmap To Base64
     */
    public static String bitmapToBase64(Bitmap bitmap) {
        // 要返回的字符串
        String reslut = null;
        ByteArrayOutputStream baos = null;
        try {
            if (bitmap != null) {
                baos = new ByteArrayOutputStream();
                //压缩只对保存有效果bitmap还是原来的大小
                bitmap.compress(Bitmap.CompressFormat.JPEG, 30, baos);
                baos.flush();
                baos.close();
                // 转换为字节数组
                byte[] byteArray = baos.toByteArray();
                // 转换为字符串
                reslut = Base64.encodeToString(byteArray, Base64.NO_WRAP);
            } else {
                return null;
            }
        } catch (IOException e) {
            e.printStackTrace();
        } finally {
            try {
                if (baos != null) {
                    baos.close();
                }
            } catch (IOException e) {
                e.printStackTrace();
            }
        }
        return reslut;
    }
 
    /**
     * Bitmap To Bitmap
     */
    public static Bitmap base64ToBitmap(String base64String) {
        byte[] decode = Base64.decode(base64String, Base64.DEFAULT);
        Bitmap bitmap = BitmapFactory.decodeByteArray(decode, 0, decode.length);
        return bitmap;
    }
 
    /**
     * Bitmap 转化为 二维数组
     */
    public static byte[] getBytesByBitmap(Bitmap bitmap) {
        try {
            ByteArrayOutputStream outputStream = new ByteArrayOutputStream(bitmap.getByteCount());
            bitmap.compress(Bitmap.CompressFormat.PNG, 100, outputStream);
            return outputStream.toByteArray();
        } catch (Exception e) {
            return new byte[10];
        }
    }
 
    /**
     * 文件 转 base64字符串
     */
    public static String fileToBase64(File file) {
        String base64 = null;
        try {
            InputStream in = new FileInputStream(file);
            byte[] bytes = new byte[in.available()];
            int length = in.read(bytes);
            base64 = Base64.encodeToString(bytes, 0, length, Base64.DEFAULT);
            in.close();
        } catch (Exception e) {
        }
        return base64;
    }
 
    /**
     * Bitmap 转 文件
     */
    public static File bitmapToFile(Bitmap bitmap) {
        ByteArrayOutputStream baos = new ByteArrayOutputStream();
        //第二个参数是压缩比重，图片存储在磁盘上的大小会根据这个值变化。值越小存储在磁盘的图片文件越小，
        bitmap.compress(Bitmap.CompressFormat.JPEG, 50, baos);
        File fileDir = new File(Base64Util.Mzz_File);
        if (!fileDir.exists()) {
            fileDir.mkdirs();
        }
        File file = new File(Mzz_File, System.currentTimeMillis() + "压缩图片_Mzz.jpg");
        try {
            FileOutputStream fos = new FileOutputStream(file);
            InputStream is = new ByteArrayInputStream(baos.toByteArray());
            int x = 0;
            byte[] b = new byte[1024 * 100];
            while ((x = is.read(b)) != -1) {
                fos.write(b, 0, x);
            }
            fos.close();
        } catch (Exception e) {
            Log_Ma.e(TAG, e.toString());
            e.printStackTrace();
        }
        return file;
    }
 
    public static String encode(byte[] from) {
        StringBuilder to = new StringBuilder((int) ((double) from.length * 1.34D) + 3);
        int num = 0;
        char currentByte = 0;
 
        int i;
        for (i = 0; i < from.length; ++i) {
            for (num %= 8; num < 8; num += 6) {
                switch (num) {
                    case 0:
                        currentByte = (char) (from[i] & lead6byte);
                        currentByte = (char) (currentByte >>> 2);
                    case 1:
                    case 3:
                    case 5:
                    default:
                        break;
                    case 2:
                        currentByte = (char) (from[i] & last6byte);
                        break;
                    case 4:
                        currentByte = (char) (from[i] & last4byte);
                        currentByte = (char) (currentByte << 2);
                        if (i + 1 < from.length) {
                            currentByte = (char) (currentByte | (from[i + 1] & lead2byte) >>> 6);
                        }
                        break;
                    case 6:
                        currentByte = (char) (from[i] & last2byte);
                        currentByte = (char) (currentByte << 4);
                        if (i + 1 < from.length) {
                            currentByte = (char) (currentByte | (from[i + 1] & lead4byte) >>> 4);
                        }
                }
 
                to.append(encodeTable[currentByte]);
            }
        }
 
        if (to.length() % 4 != 0) {
            for (i = 4 - to.length() % 4; i > 0; --i) {
                to.append("=");
            }
        }
 
        return to.toString();
    }
 
    /**
     * @param key      加密秘钥
     * @param filepath 源文件地址
     */
    public static Map<String, String> IMG_Jiami(int key, String filepath) {
        File fileDir = new File(Base64Util.Mzz_File);
        if (!fileDir.exists()) {
            fileDir.mkdirs();
        }
        File file = new File(fileDir, System.currentTimeMillis() + "_Mzz.jpg");
        String path_jiami;
        long available = 0;
        try {
            BufferedInputStream bis = new BufferedInputStream(new FileInputStream(filepath));
            available = bis.available();
            BufferedOutputStream bos = new BufferedOutputStream(new FileOutputStream(file.getPath()));
            int b;
            while ((b = bis.read()) != -1) {
                bos.write(b ^ key);
            }
            path_jiami = file.getPath();
            bis.close();
            bos.close();
        } catch (Exception e) {
            path_jiami = filepath;
        }
        Map<String, String> map = new HashMap<>();
        map.put("path", path_jiami);
        map.put("size", available + "");
        return map;
    }
 
    /**
     * 获取视频封面
     */
    public static Bitmap getVideoThumb(String path) {
        MediaMetadataRetriever media = new MediaMetadataRetriever();
        media.setDataSource(path);
        return media.getFrameAtTime();
    }
 
    /**
     * 获取视频时长
     */
    public static long getLocalVideoDuration(String videoPath) {
        int duration;
        try {
            MediaMetadataRetriever mmr = new MediaMetadataRetriever();
            mmr.setDataSource(videoPath);
            duration = Integer.parseInt(mmr.extractMetadata
                    (MediaMetadataRetriever.METADATA_KEY_DURATION));
        } catch (Exception e) {
            e.printStackTrace();
            return 0;
        }
        return duration;
    }
 
    /**
     * @return view的截图，在InVisible时也可以获取到bitmap
     */
    public static Bitmap getViewBitmap(View view) {
        view.measure(View.MeasureSpec.makeMeasureSpec(view.getMeasuredWidth(), View.MeasureSpec.EXACTLY),
                View.MeasureSpec.makeMeasureSpec(view.getMeasuredHeight(), View.MeasureSpec.EXACTLY));
        view.setDrawingCacheQuality(View.DRAWING_CACHE_QUALITY_HIGH);
        view.setDrawingCacheEnabled(true);
        view.buildDrawingCache(true);
        return view.getDrawingCache(true);
    }
 
    /**
     * 获取系统相册文件路径
     */
    public static File getDCIMDirectory() {
        File dcim = Environment.getExternalStoragePublicDirectory(Environment.DIRECTORY_DCIM);
        if (!dcim.exists()) {
            dcim = Environment.getExternalStoragePublicDirectory(Environment.DIRECTORY_PICTURES);
        }
        return dcim;
    }
 
    /**
     * 根据绝对路径得到图片的宽高，亲测比楼上速度快几十倍
     *
     * @param path 绝对路径！绝对路径！绝对路径！
     * @return 宽高
     */
    public static int[] getImageWidthHeight(String path) {
        try {
            BitmapFactory.Options options = new BitmapFactory.Options();
            options.inJustDecodeBounds = true;
            BitmapFactory.decodeFile(path, options);
            return new int[]{options.outWidth, options.outHeight};
        } catch (Exception e) {
            e.printStackTrace();
        }
        return new int[]{0, 0};
    }
 
    /**
     * 根据相对路径获取图片宽高
     *
     * @param c   上下文
     * @param uri 图片uri地址
     * @return 宽高信息
     */
 
    public static int[] getImageWidthHeight(Context c, Uri uri) {
        try {
            ParcelFileDescriptor parcelFileDescriptor = c.getContentResolver()
                    .openFileDescriptor(uri, "r");
            if (parcelFileDescriptor != null) {
                FileDescriptor fileDescriptor = parcelFileDescriptor.getFileDescriptor();
                Bitmap image = BitmapFactory.decodeFileDescriptor(fileDescriptor);
                parcelFileDescriptor.close();
                return new int[]{image.getWidth(), image.getHeight()};
            }
        } catch (Exception e) {
            e.printStackTrace();
        }
 
        return new int[]{0, 0};
    }
 
    /**
     * @param context
     * @param filePath  路径
     * @param reqWidth  要求压缩的宽
     * @param reqHeight 要求压缩的高
     * @return
     */
    public static Bitmap getSmallBitmap(Context context, String filePath, int reqWidth, int reqHeight) {
        final BitmapFactory.Options options = new BitmapFactory.Options();
        options.inJustDecodeBounds = true;//只解析图片边沿，获取宽高
        // 计算缩放比
        options.inSampleSize = calculateInSampleSize(options, reqWidth, reqHeight);
        // 完整解析图片返回bitmap
        options.inJustDecodeBounds = false;
        return BitmapFactory.decodeFile(filePath, options);
    }
 
    /**
     * @param context
     * @param filePath  路径
     * @param reqWidth  要求压缩的宽
     * @param reqHeight 要求压缩的高
     * @return
     */
    public static Bitmap getSmallBitmap(Context context, int filePath, int reqWidth, int reqHeight) {
        final BitmapFactory.Options options = new BitmapFactory.Options();
        options.inJustDecodeBounds = true;//只解析图片边沿，获取宽高
        // 计算缩放比
        options.inSampleSize = calculateInSampleSize(options, reqWidth, reqHeight);
        // 完整解析图片返回bitmap
        options.inJustDecodeBounds = false;
        return BitmapFactory.decodeResource(context.getResources(), filePath, options);
    }
 
    public static 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) {
            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;
    }
}