使用Python套接字编程发送图像

Question

我正在尝试使用Python的套接字编程发送图像文件。我能够发送文本文件，但一直在尝试发送图像文件。我打开并读取图像文件内容到字符串中，然后将其发送，并在客户端接收并写入以不同目录下相同名称的文件中，但我无法打开该文件。同时，我会附上我的代码。注释部分表明我已经尝试过了。此外，我还遇到了发送整数size的问题，但在另一端收到了随机字符串。

这是服务器脚本：

import socket
server_socket = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
server_socket.bind(("", 5000))
server_socket.listen(5)
import os


client_socket, address = server_socket.accept()
print "Conencted to - ",address,"\n"
while (1):
    choice = client_socket.recv(1024)
    choice = int(choice)
    if(choice == 1):
        data = client_socket.recv(1024)
        print "The following data was received - ",data
        print "Opening file - ",data
        fp = open(data,'r')
        strng = fp.read()
        size = os.path.getsize(data)
        size = str(size)
        client_socket.send(size)
        client_socket.send (strng)
        #client_socket.close()

    if (choice == 2):
        data = client_socket.recv(1024)
        print "The following data was received - ",data
        print "Opening file - ",data
        fp = open(data,'r')
        strng = fp.read()
        #strng = str(fp)
        size = os.path.getsize(data)
        print size
        size = str(size)
        print size
        client_socket.send(size)
        client_socket.send (strng)
        #client_socket.close()

这是客户端脚本 -

#!/usr/bin/python
# TCP client example
import socket,os
client_socket = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
client_socket.connect(("", 5000))
k = ' '
size = 1024

while(1):
    print "Do you want to transfer a \n1.Text File\n2.Image\n3.Video\n"
    k = raw_input()
    client_socket.send(k)
    k = int (k)
    if(k == 1):
        print "Enter file name\n"
        strng = raw_input()
        client_socket.send(strng)
        size = client_socket.recv(1024)
        size = int(size)
        print "The file size is - ",size," bytes"
        size = size*2
        strng = client_socket.recv(size)
        print "\nThe contents of that file - "
        print strng

    if (k==2):
        print "Enter file name of the image with extentsion (example: filename.jpg,filename.png) - "
        fname = raw_input()
        client_socket.send(fname)
        size = client_socket.recv(1)
        print size
        #size = int(size)
        print "The file size is - ",size
        size = size*2
        strng = client_socket.recv(256456)
        print "\nThe file will be saved and opened- "
        fname = 'downloads/'+fname
        nf = open(fname,'w')
        nf.write(strng)
        nf.close()
        fname = 'viewnior '+ fname
        print fname
        os.system(fname)

我正在使用 Crunchbang Linux——一款非官方的基于 Debian 的发行版，viewnior 是图片查看器。

- mihirk

---

你尝试过调试它吗？print repr(client)？ - Glaslos

会尝试一下，谢谢。我已经尝试使用vimdiff比较新创建的文件和原始文件，结果显示这两个文件是相同的，但是新创建的图像仍然无法打开。原始图像和克隆图像的大小以及内容都是相同的。 - mihirk

Answer 1

谢谢你，Sanket。 :D 我之前遇到了一个发送大数据块的问题，所以我把它分成了512字节，现在即使是视频也可以完美地工作了。 :D 只需要添加pygtk界面来确认接收和发送文件即可。 :D

#!/usr/bin/python
# TCP client example
import socket,os
client_socket = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
client_socket.connect(("", 5005))
k = ' '
size = 1024

while(1):
    print "Do you want to transfer a \n1.Text File\n2.Image\n3.Video\n"
    k = raw_input()
    client_socket.send(k)
    k = int (k)
    if(k == 1):
        print "Enter file name\n"
        strng = raw_input()
        client_socket.send(strng)
        size = client_socket.recv(1024)
        size = int(size)
        print "The file size is - ",size," bytes"
        size = size*2
        strng = client_socket.recv(size)
        print "\nThe contents of that file - "
        print strng

    if (k==2 or k==3):
        print "Enter file name of the image with extentsion (example: filename.jpg,filename.png or if a video file then filename.mpg etc) - "
        fname = raw_input()
        client_socket.send(fname)
        fname = 'documents/'+fname
        fp = open(fname,'w')
        while True:
            strng = client_socket.recv(512)
            if not strng:
                break
            fp.write(strng)
        fp.close()
        print "Data Received successfully"
        exit()
        #data = 'viewnior '+fname
        #os.system(data)

以下是服务器端代码

import socket
server_socket = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
server_socket.bind(("", 5005))
server_socket.listen(5)
import os


client_socket, address = server_socket.accept()
print "Conencted to - ",address,"\n"
while (1):
    choice = client_socket.recv(1024)
    choice = int(choice)
    if(choice == 1):
        data = client_socket.recv(1024)
        print "The following data was received - ",data
        print "Opening file - ",data
        fp = open(data,'r')
        strng = fp.read()
        size = os.path.getsize(data)
        size = str(size)
        client_socket.send(size)
        client_socket.send (strng)
        #client_socket.close()

    if (choice == 2 or choice == 3):
        data = client_socket.recv(1024)
        print "The following data was received - ",data
        print "Opening file - ",data
        img = open(data,'r')
        while True:
            strng = img.readline(512)
            if not strng:
                break
            client_socket.send(strng)
        img.close()
        print "Data sent successfully"
        exit()
        #data = 'viewnior '+data
        #os.system(data)

- mihirk

---

首先感谢您提供的有用帖子，但是我遇到了一个问题。当运行两个发送图像的脚本时，它会打印“数据已成功发送”并停止，尽管接收到的图像应该在代码中稍后使用。我是这样使用它的:input_image = Image.open("data").convert('L').resize((100, 100)) - user2229953

我无法在Windows上运行这个程序。将两个文件中的open(data,'r')更改为open(data,'rb')，并用read替换readline来以二进制传输数据解决了我的问题。 - SkyNT

Answer 2

我在我的系统上（Ubuntu 11.10）运行了相同的代码，并发现将大小作为字符串发送时存在问题。当我插入处理该部分逻辑时，它运行得很顺利。我也能打开文件。 这是我如何解决您的问题： 客户端代码（client.py）中的第一个更改是在接受大小并发送关于其确认时：

size = ' '
while(1):
   tmpsize = client_socket.recv(1)
   if tmpsize.isdigit() == True:
      print "Here : ",tmpsize
      size += tmpsize
   else:
      break

client_socket.send("received")

第二个更改是在服务器端（server.py）代码中，以接收确认。

client_socket.send(size)
ack = client_socket.recv(1024)
if ack == "received":
   client_socket.send (strng)

我希望这能帮助您解决问题。

- curiousMind

---

谢谢Sanket。我解决了问题。但是，问题在于我发送大文件时会遇到问题，因此我决定逐行发送它们。这是修订后的代码:D - mihirk