如何显示JPEG图像直接从字节数组（之前保存图像）？ [英] How to display the JPEG Image directly from byte array (Before saving Image)?

问题描述

我收到一个JPEG图像（图像尺寸：50KB）从客户端套接字，并在模拟器SD卡保存。从那里，我在显示的ImageView的jpg图片。但我想在SD卡存储图像，因为我们的Andr​​oid APPLI从插座接收连续图像，如果我按照接收，存储和显示方法，那么它会变得非常缓慢的过程之前，展示形象，所以要增加我想要的速度仅RAM显示器。为此，我需要暂时保存图像阵列上的RAM。从那里，我刨显示，通过使用单独的线程保存。所以，请指导我如何显示来自字节数组的形象。

注：我从插座接收JPEG图像，而不是.BMP或.gif或.png

下面是我的code从TCP套接字接收图像。 （其工作罚款）
（注：这是在单独的线程中完成的，不要尝试在UI线程）

 字节公众[] = mybytearray新的字节[310000]。
                    私人INT读取动作= 0;
                    私人INT电流= 0;                    ServerSocket的ServerSocket的=新的ServerSocket（SERVERPORT）;
                    客户端的Socket的ServerSocket.accept =（）;
                   尝试{                       MYDIR =新的文件（到/ mnt / SD卡/ saved_images）;                        如果（！myDir.exists（））{
                            myDir.mkdir（）;
                        }其他{
                            Log.d（ServerActivity，文件夹已创建）;
                        }                        字符串fpath =/image0001.jpg;
                        档案文件=新的文件（MYDIR，fpath）;
                        如果（file.exists（））file.delete（）;
                        InputStream为= client.getInputStream（）;
                        FOS的FileOutputStream =新的FileOutputStream（文件）;
                        BOS的BufferedOutputStream =新的BufferedOutputStream（FOS）;
                        读取动作= is.​​read（mybytearray，0，mybytearray.length）;
                        电流=读取动作;                 做{
                      读取动作= is.​​read（mybytearray，电流，（mybytearray.length电流））;
                      如果（读取动作＆GT; = 0）电流+ =读取动作;                 }而（读取动作-1个）;                        bos.write（mybytearray，0，电流）;                        Log.d（ServerActivity，从阵列图像复原）;                        bos.flush（）;
                        bos.close（）;
                        fos.flush（）;
                        fos.close（）;
                        is.close（）;
                        client.close（）;
                        serverSocket.close（）;
                    }赶上（例外五）{
                  e.printStackTrace（）;
              }
 

解决方案

尝试插入此code片段到code：

  {做
    读取动作= is.​​read（mybytearray，电流，（mybytearray.length电流））;
    如果（读取动作＆GT; = 0）电流+ =读取动作;
}而（读取动作-1个）;ByteArrayInputStream进行的InputStream =新ByteArrayInputStream进行（myByteArray）;
位= BitmapFactory.de codeStream（InputStream的）;
ImageView的照片=新ImageView的（本）;
picture.setImageBitmap（位图）;bos.write（mybytearray，0，电流）;
 

I am receiving a jpeg image (Image size: 50KB) from client socket and saving in emulator SD Card. From there I am displaying the jpg image in Imageview. But I want to display the image before saving image on the SD Card because our android appli will receive the continous images from sockets, If I follow receive, save and display method then it will become very slow process, so to increase the speed I want display from ram only. For this I need to save the image array temporarily on the RAM. From there I planed to display and save by using the separate threads. So please guide me how to display the image from byte array.

Note: I am receiving JPEG image from socket, not .bmp or .gif or .png.

Below is my code for receiving the image from tcp socket. (Its working fine) (Note: This is done in seperate thread, don't try it in UI thread.)

                    public byte[] mybytearray  = new byte[310000];
                    private int bytesRead=0;
                    private int current = 0;

                    ServerSocket serverSocket = new ServerSocket(SERVERPORT);  
                    Socket client = serverSocket.accept(); 


                   try {

                       myDir=new File("/mnt/sdcard/saved_images");

                        if (!myDir.exists()){
                            myDir.mkdir();
                        }else{
                            Log.d("ServerActivity","Folder Already created" );
                        }

                        String fpath = "/image0001.jpg";
                        File file = new File (myDir, fpath);
                        if (file.exists ()) file.delete ();


                        InputStream is = client.getInputStream();
                        FileOutputStream fos = new FileOutputStream(file);
                        BufferedOutputStream bos = new BufferedOutputStream(fos);
                        bytesRead = is.read(mybytearray,0,mybytearray.length);
                        current = bytesRead;

                 do {
                      bytesRead = is.read(mybytearray, current, (mybytearray.length-current));
                      if(bytesRead >= 0) current += bytesRead;

                 } while(bytesRead > -1);

                        bos.write(mybytearray, 0 , current);

                        Log.d("ServerActivity","Reconstructing Image from array");

                        bos.flush();
                        bos.close();
                        fos.flush();
                        fos.close();
                        is.close();
                        client.close();
                        serverSocket.close();
                    } catch (Exception e) { 
                  e.printStackTrace();
              }

解决方案

Try inserting this code snippet into your code:

do {
    bytesRead = is.read(mybytearray, current, (mybytearray.length-current));
    if(bytesRead >= 0) current += bytesRead;
} while(bytesRead > -1);

ByteArrayInputStream inputStream = new ByteArrayInputStream(myByteArray);
bitmap = BitmapFactory.decodeStream(inputStream);
ImageView picture = new ImageView(this);
picture.setImageBitmap(bitmap);

bos.write(mybytearray, 0 , current);

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