Android关于图片处理及Bitmap处理的几种方法

根据图片uri生成Bitmap对象

    public static Bitmap decodeUriAsBitmap(Context context, Uri uri) {
        if (uri == null) return null;
        Bitmap bitmap = null;
        try {
            bitmap = BitmapFactory.decodeStream(context.getContentResolver().openInputStream(uri));
        } catch (FileNotFoundException e) {
            e.printStackTrace();
            return null;
        }
        return bitmap;
    }

bitmap 转base64

public static String getBitmapBase64String(Bitmap bitmap) {
        ByteArrayOutputStream out = new ByteArrayOutputStream();
        bitmap.compress(Bitmap.CompressFormat.JPEG, 100, out);
        try {
            out.flush();
            out.close();
        } catch (IOException e) {
            e.printStackTrace();
        }
        return Base64.encodeToString(out.toByteArray(), Base64.DEFAULT);
    }

base64转成bitmap

public static Bitmap StringToBitmap(String st) {
        // OutputStream out;
        Bitmap bitmap = null;
        try {
            // out = new FileOutputStream("/sdcard/aa.jpg");
            byte[] bitmapArray;
            bitmapArray = Base64.decode(st, Base64.DEFAULT);
            bitmap =
                    BitmapFactory.decodeByteArray(bitmapArray, 0,
                            bitmapArray.length);
            // bitmap.compress(Bitmap.CompressFormat.PNG, 100, out);
            return bitmap;
        } catch (Exception e) {
            return null;
        }
    }

本地图片路径String转base64

public static String getFileBase64String(String path) {
        File file = new File(path);
        try {
            FileInputStream is = new FileInputStream(file);
            ByteArrayOutputStream out= new ByteArrayOutputStream();
            int i = is.read();
            while (i != -1) {
                out.write(i);
                i= is.read();
            }
            return Base64.encodeToString(out.toByteArray(), Base64.DEFAULT);
        } catch (IOException e1) {
            e1.printStackTrace();
        }
        return null;

    }

加载本地图片

public static Bitmap getLoacalBitmap(String url) {
        try {
            FileInputStream fis = new FileInputStream(url);
            return BitmapFactory.decodeStream(fis);
        } catch (FileNotFoundException e) {
            e.printStackTrace();
            return null;
        }
    }

从服务器取图片

public static Bitmap getHttpBitmap(final String url) {
        class MyThread extends Thread {
            @Override
            public void run() {
                try {
                    myFileUrl = new URL(url);
                    HttpURLConnection conn = (HttpURLConnection) myFileUrl.openConnection();
                    conn.setConnectTimeout(0);
                    conn.setDoInput(true);
                    conn.connect();
                    InputStream is = conn.getInputStream();
                    bitmap = BitmapFactory.decodeStream(is);
                    is.close();
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
        }
        //处理异步线程，以获得返回值
        MyThread thread = new MyThread();
        thread.start();
        try {
            thread.join();
        } catch (InterruptedException e) {
            e.printStackTrace();
        }
        return bitmap;
    }

将Bitmap保存在本地

public static void saveBitmap(Context context, Bitmap bitmap) {
        // 首先保存图片
        File appDir = new File(Environment.getExternalStorageDirectory(),
                "BrotherRepair");
        if (!appDir.exists()) {
            appDir.mkdir();
        }
        String fileName = "BrotherRepair" + ".png";
        File file = new File(appDir, fileName);
        try {
            FileOutputStream fos = new FileOutputStream(file);
            bitmap.compress(Bitmap.CompressFormat.JPEG, 100, fos);
            fos.flush();
            fos.close();
        } catch (FileNotFoundException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        }
        // 把文件插入到系统图库
        try {
            MediaStore.Images.Media.insertImage(context.getContentResolver(),
                    file.getAbsolutePath(), fileName, null);
        } catch (FileNotFoundException e) {
            e.printStackTrace();
        }
        // 通知图库更新
        context.sendBroadcast(new Intent(Intent.ACTION_MEDIA_SCANNER_SCAN_FILE,
                Uri.parse("file://" + "/sdcard/namecard/")));
    }

bitmap转换成byte数组

   /**
     * bitmap转换成byte数组
     *
     * @param bitmap
     * @param needRecycle
     * @return
     */
    public static byte[] bitmapToByteArray(Bitmap bitmap, boolean needRecycle) {
        if (null == bitmap) {
            return null;
        }
        if (bitmap.isRecycled()) {
            return null;
        }

        ByteArrayOutputStream output = new ByteArrayOutputStream();
        bitmap.compress(Bitmap.CompressFormat.PNG, 100, output);
        if (needRecycle) {
            bitmap.recycle();
        }

        byte[] result = output.toByteArray();
        try {
            output.close();
        } catch (Exception e) {
        }
        return result;
    }