Question

下面是使用套接字从客户端向服务器发送图像数据的代码段。

虽然代码在 Python2 上运行没有任何问题，但是在 Python3

中出现以下错误

server.py:
===========
import socket
import sys
import cv2
import pickle
import numpy as np
import struct ## new

HOST=''
PORT=8089

s=socket.socket(socket.AF_INET,socket.SOCK_STREAM)
print('Socket created')

s.bind((HOST,PORT))
print('Socket bind complete')
s.listen(10)
print('Socket now listening')

conn,addr=s.accept()

### new
data = ""
payload_size = struct.calcsize("L") 
while True:
    while len(data) < payload_size:
        data += conn.recv(4096)
    packed_msg_size = data[:payload_size]
    data = data[payload_size:]
    msg_size = struct.unpack("L", packed_msg_size)[0]
    while len(data) < msg_size:
        data += conn.recv(4096)
    frame_data = data[:msg_size]
    data = data[msg_size:]
    ###

    frame=pickle.loads(frame_data)
    print(frame)
    cv2.imshow('frame',frame)

    key = cv2.waitKey(10)
    if (key == 27) or (key == 113):
        break

# cap.release()
cv2.destroyAllWindows()


Error in server.py:
====================
$ python3 server.py
Socket created
Socket bind complete
Socket now listening
Traceback (most recent call last):
  File "server.py", line 26, in <module>
    data += conn.recv(4096)
TypeError: must be str, not bytes




client.py:
===========
import cv2
import numpy as np
import socket
import sys
import pickle
import struct ### new code
cap=cv2.VideoCapture(0)
clientsocket=socket.socket(socket.AF_INET,socket.SOCK_STREAM)
clientsocket.connect(('localhost',8089))
while True:
    ret,frame=cap.read()
    data = pickle.dumps(frame) ### new code
    clientsocket.sendall(struct.pack("L", len(data))+data) ### new code



Error in client.py:
===================
$ python3 client.py
Traceback (most recent call last):
  File "client.py", line 13, in <module>
    clientsocket.sendall(struct.pack("L", len(data))+data) ### new code
BrokenPipeError: [Errno 32] Broken pipe

Answer 1

在将struct.pack（“ L”，len（data））代码分离到client.py文件中的新行之后，我在 Python3 上将其唤醒。

下面是更新的代码：

server.py
=========
import pickle
import socket
import struct

import cv2

HOST = ''
PORT = 8089

s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
print('Socket created')

s.bind((HOST, PORT))
print('Socket bind complete')
s.listen(10)
print('Socket now listening')

conn, addr = s.accept()

data = b'' ### CHANGED
payload_size = struct.calcsize("L") ### CHANGED

while True:

    # Retrieve message size
    while len(data) < payload_size:
        data += conn.recv(4096)

    packed_msg_size = data[:payload_size]
    data = data[payload_size:]
    msg_size = struct.unpack("L", packed_msg_size)[0] ### CHANGED

    # Retrieve all data based on message size
    while len(data) < msg_size:
        data += conn.recv(4096)

    frame_data = data[:msg_size]
    data = data[msg_size:]

    # Extract frame
    frame = pickle.loads(frame_data)

    # Display
    cv2.imshow('frame', frame)
    ch = cv2.waitKey(1)
    if ch & 0xFF == ord('q'):
        break

cap.release()
cv2.destroyAllWindows()



client.py
=========
import cv2
import numpy as np
import socket
import sys
import pickle
import struct

cap=cv2.VideoCapture(0)
clientsocket=socket.socket(socket.AF_INET,socket.SOCK_STREAM)
clientsocket.connect(('localhost',8089))

while True:
    ret,frame=cap.read()
    # Serialize frame
    data = pickle.dumps(frame)

    # Send message length first
    message_size = struct.pack("L", len(data)) ### CHANGED

    # Then data
    clientsocket.sendall(message_size + data)


cap.release()
cv2.destroyAllWindows()

Python3套接字TypeError：必须为str，而不是字节

1 个答案: