Question

所以这就是我要做的事情：有这个图像服务器将在端口5003上发送数据它将传输的数据格式如下图像类型为1个字节（0 =原始，1 = JPEG）然后是图像大小的下一个4字节然后在那之后将有n个字节，具有以下顺序宽度为2字节，高度为2字节，B为1字节，R为1字节，G

为1字节

所以我要做的是获取数据并使用以下代码将其转换为图像：

#! /usr/bin/python
import socket
import sys
import binascii
from PIL import Image
from StringIO import StringIO


# Connect to the server image
serverHost = 'localhost'
serverPort = 5003
s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
s.connect((serverHost, serverPort))

print >>sys.stderr, 'Connecting to host: ' +  str(serverHost) 
print >>sys.stderr, 'and server Port: ' + str(serverPort)

s.settimeout(1)

#Receive the image type
imageType = s.recv(1)
print>>sys.stderr, 'received %r' %binascii.hexlify(imageType)
print>>sys.stderr, 'Unpacked: ', int(binascii.hexlify(imageType), 16)
received = imageType.__len__()
print>> sys.stderr, "Received: ", received 

#Receive the image size
imageSize = s.recv(4)
print>>sys.stderr, 'received %r' %binascii.hexlify(imageSize)
print>>sys.stderr, 'Unpacked: ', int(binascii.hexlify(imageSize), 16)
received = imageSize.__len__()
print>> sys.stderr, "Received: ", received 


#Receive the image Data
imageData = ''
received =0
while(received < int(binascii.hexlify(imageSize), 16)):
  buffer = s.recv(4096)
  imageData += buffer
  received += buffer.__len__()
  print>> sys.stderr, "Received: ", received 

img = Image.fromstring('RGB', (1280, 720), imageData, 'raw')

#img = Image.open(StringIO(binascii.hexlify(imageData)))
img = img.convert('RGB')
img.save('out.png')

#file = open('test.png', 'w');
#file.write(imageData)
#file.close()

#When we receive the image, we send the acknowledgement
s.send('OK')
s.close()`enter code here`

但每次我运行代码时总是会出现这种错误

"Value error not enough Image Data"

如果改变

img = Image.fromstring('RGB', (1280, 720), imageData, 'raw')

到

img = Image.fromstring('BRG', (1280, 720), imageData, 'raw')

我收到此错误：

Value error: Unrecognized mode,

任何人都知道如何解决这类问题？

Answer 1

最好在完全给出服务器和客户端的代码时调试这些问题（但只是简单地显示问题）。

因此，以下是基于您的初始代码和描述的非常基本的客户端。请注意，image_type未使用，它就在那里，因为您提到要区分JPEG和RAW。我总是假设收到的数据是RGB数据，您可以根据实际问题进行调整。这里的主要区别是使用struct，这是一种标准方式，以通用格式打包数据以通过网络发送，并避免与字节排序相关的问题。此代码还希望接收图像宽度和高度（代码中不存在），因此您可以在客户端重建图像。

import socket
import struct
from PIL import Image

def recv(sock, size):
    data = ''
    to_receive = size
    while to_receive > 0:
        data += sock.recv(size)
        to_receive = size - len(data)
    return data

serv_host = ''
serv_port = 5003

s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
s.connect((serv_host, serv_port))

s.settimeout(1)

image_type = struct.unpack('!b', recv(s, 1))[0]
print "Image type: %d" % image_type
image_size = struct.unpack('!i', recv(s, 4))[0]
print "Image size: %d" % image_size
image_width, image_height = struct.unpack('!hh', recv(s, 4))
print "Image dimensions: %d x %d" % (image_width, image_height)

# Receive image data
image_data = recv(s, image_size)
print len(image_data)

# When we receive the image, we send the acknowledgement.
s.send('OK')
s.close()

img = Image.fromstring('RGB', (image_width, image_height), image_data)
img.save('out.png')

由于未包含服务器，因此以下是一个尊重您所描述的协议的简单服务器。我没有费心检查服务器中完全接收的数据。另请注意，此服务器仅提供运行时在命令行中指定的单个映像。再次，适应您的问题。还要注意我没有发送图像模式，这可能是实际应用中的一个问题。

import sys
import socket
import struct
from PIL import Image

host = ''
port = 5003
backlog = 5

serv_img = Image.open(sys.argv[1])
simg_size = serv_img.size
serv_data = serv_img.tostring()
data_size = len(serv_data)

print "Serving data of size %d" % data_size

s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
s.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
s.bind((host, port))
s.listen(backlog)
while True:
    client, address = s.accept()

    client.sendall(struct.pack('!b', 1))
    client.sendall(struct.pack('!i', data_size))
    client.sendall(struct.pack('!hh', *simg_size))
    client.sendall(serv_data)

    data = client.recv(2)
    if data == 'OK':
        print "OK", address

    client.close()

关于不使用__len__的引发注释仅仅是因为它是Python中的一种特殊方法，由len本身调用。如果你没有任何充分的理由使用特殊方法，那么就不要这样做。

Answer 2

您提到过使用USARSim的图像服务器。这是我用于从USARSim（UT2004版本）接收图像的代码：

def get_image(sock):    
    image_type = struct.unpack('b', sock.recv(1))[0]    
    image_size = struct.unpack('>i', sock.recv(4))[0]

    if image_size < 250000:      
        image_data = ""
        received = 0
        while (received < image_size):
            data = sock.recv(image_size-received)
            received += len(data)
            image_data += data        

        filename = "image_%s.jpg" % str(now())
        with open(filename, "wb") as f:
            f.write(image_data)

def write_ack(sock):
    sock.send("OK")

def main():
   sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
   sock.connect((host, port))

   while True:
       get_image(sock)
       write_ack(sock)

二进制数据图像原始python

2 个答案: