使用套接字通过Python从Android手机向PC发送图像文件

Question

我想通过套接字将图像从android设备发送到python，我已经成功地从android python发送了文本。 当我发送图像时，我会收到正在发送的图像，但在接收端，图像已损坏，大小为0 KB 我感谢任何帮助，因为我现在被困在这里

这是我的密码

image.py

from socket import *

port = 8888
s = socket(AF_INET, SOCK_STREAM)
s.bind(('', port))
s.listen(1) #listens to 1 connection
conn, addr = s.accept()
print("Connected by the ",addr)

while True:
    data = conn.recv(1024)
    with open('image.jpg', 'wb') as file:
       file.write(data)


conn.close() 

Android端代码是

public void send(View v) {
        Intent i = new Intent(Intent.ACTION_OPEN_DOCUMENT);
        i.addCategory(Intent.CATEGORY_OPENABLE);
        i.setType("image/*");
        startActivityForResult(i, 1);
    }

 @Override
    protected void onActivityResult(int requestCode, int resultCode, @Nullable Intent data) {
        if (requestCode == 1 && resultCode == RESULT_OK) {

            try {
                final Uri imageUri = data.getData();
                final InputStream imageStream = getContentResolver().openInputStream(imageUri); 
                final Bitmap selectedImage = BitmapFactory.decodeStream(imageStream);
                imageView.setImageBitmap(selectedImage);

                ByteArrayOutputStream byteArrayOutputStream = new ByteArrayOutputStream();
                selectedImage.compress(Bitmap.CompressFormat.JPEG, 100, byteArrayOutputStream);
                byte[] array = byteArrayOutputStream.toByteArray();

                SendImageClient sendImageClient = new SendImageClient();
                sendImageClient.execute(array);

            } catch (FileNotFoundException e) {
                e.printStackTrace();
            }

        } else {
            Toast.makeText(this, "no image selected", Toast.LENGTH_SHORT).show();
        }

    }


 public class SendImageClient extends AsyncTask<byte[], Void, Void> {


        @Override
        protected Void doInBackground(byte[]... voids) {

            try {
                Socket socket= new Socket("192.168.0.106",8888);

                OutputStream out=socket.getOutputStream();
                DataOutputStream dataOutputStream=new DataOutputStream(out);
                dataOutputStream.writeInt(voids[0].length);
                dataOutputStream.write(voids[0],0,voids[0].length);
                handler.post(new Runnable() {
                    @Override
                    public void run() {
                        Toast.makeText(MainActivity.this, "Image sent", Toast.LENGTH_SHORT).show();
                    }
                });

                dataOutputStream.close();
                out.close();
                socket.close();

            } catch (IOException e) {
                e.printStackTrace();
            }


            return null;
        }
    }

Answer 1

每次循环运行时，python代码都会截断输出文件。在最后一次运行时，当连接关闭时，文件被截断，conn.recv将返回一个空字符串，并且不会向文件写入任何其他内容

将with open(..)移动到从套接字读取的循环之外，并处理连接关闭，这样就不会有无限循环：

with open('image.jpg', 'wb') as file:
    while True:
        data = conn.recv(1024)
        if not data: break
        file.write(data)

java代码在发送数据之前先发送它所发送的数据的大小——您应该删除它或调整python代码以考虑这一点

            dataOutputStream.writeInt(voids[0].length);
            dataOutputStream.write(voids[0],0,voids[0].length);