使用python中的套接字传输文件时图像失真

Question

When I transfer text files using this code, the text file received is exactly the same as the text file sent. But when I use this code to transfer image files or video files, problems arise (distortion) and I don't understand why.

Server code:

import socket
import base64

filename = open("received.jpg","a")

TCP_IP = '127.0.0.1'
TCP_PORT = 5005
BUFFER_SIZE = 1024

s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
s.bind((TCP_IP, TCP_PORT))
s.listen(1)

conn, addr = s.accept()
data = conn.recv(16)
filesize = int(data)
iter = filesize//BUFFER_SIZE
i = 0

while (i < iter):
    data = conn.recv(BUFFER_SIZE)
    filename.write(data.decode('base64'))
    if not data:
        continue
    i = i + 1

data = conn.recv((filesize - (iter*BUFFER_SIZE)))
filename.write(data.decode('base64'))
filename.close()

conn.close()

Client code:

import socket
import time
import base64

TCP_IP = '127.0.0.1'
TCP_PORT = 5005
BUFFER_SIZE = 1024

filename = open("test.jpg","rb")
MESSAGE = base64.b64encode(filename.read())
filesize = '%16s'%len(MESSAGE)

s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
s.connect((TCP_IP, TCP_PORT))
s.send(filesize)
time.sleep(1)
s.send(MESSAGE)
s.close()

Answer 1

filename = open("received.jpg","a")

应该几乎肯定是

filename = open("received.jpg","ab")