将 PIL 图像对象从套接字客户端发送到套接字服务器

Question

I want to send a PIL image object from a socket client to a socket server. Since I cannot send the image object directly over the socket, I have converted it into an array using numpy, then tried to send the array over to the socket server.

Here is my server program (the time thing is just to get a new name for the file every time I save it):

import socket
import time
import os
import sys
import Image
import ImageGrab
import numpy

sd='C:\Users\Saurabh\Desktop'
s=socket.socket()
host=socket.gethostname()          #'WarMachine'
port=12300
s.bind((host,port))

s.listen(9)

while True:
    a,addr=s.accept()
    print "got connection from",addr
    a.send("1")
    imgarr=a.recvfrom(4096)
    img=Image.fromarray(numpy.uint8(imgarr))
    sec=time.time()
    lc=time.localtime(sec)
    t=time.asctime(lc)
    print t
    strng=""+t[8:10]+"_"+t[11:13]+"_"+t[14:16]+"_"+t[17:19]
    saveas=os.path.join(sd, 'ScreenShot_'+strng+'.jpg')
    img.save(saveas)
    print "run successful server"
    a.close()

Error in Client program mentioned above is:

got connection from ('192.168.1.9', 50903)
Traceback (most recent call last):
  File "C:/Users/Saurabh/PycharmProjects/MajorProject/srvr.py", line 26, in <module>
    img=Image.fromarray(numpy.uint8(imgstr))
ValueError: invalid literal for long() with base 10: ''

And here's the client program:

import os
import sys
import time
import Image
import ImageGrab
import subprocess
import socket
import numpy

s=socket.socket()
host="WarMachine"     #use same hostname as server or else it wont work
port=12300
s.connect((host,port))

def shtDwn():
    time = 10
    subprocess.call(["shutdown.exe", "/s"])

def screenShot():
    sd='C:\Users\Saurabh\Desktop'

    img=ImageGrab.grab()
    imgarr=numpy.asarray(img)
    s.send(imgarr)
    print "run successful screentest1"


ip=s.recv(1024) 
#this receives 1 sent from server to activate snapshot function

if (ip=="1"):
    for i in range(0,10):
        screenShot()
        time.sleep(5)
elif(ip=="2"):
    shtDwn()
else:
    print"Wrong Input"

The error I am getting in above client program is:

run successful screentest1
Traceback (most recent call last):
  File "C:/Users/Saurabh/PycharmProjects/MajorProject/ScreenTest1.py", line 42, in <module>
    screenShot()
  File "C:/Users/Saurabh/PycharmProjects/MajorProject/ScreenTest1.py", line 27, in screenShot
    s.sendto(imgarr,("WarMachine",12300))
socket.error: [Errno 10054] An existing connection was forcibly closed by the remote host

By the way, I have saved images before using the program below, but I don't know what's wrong in my program above.

Previous program without client and server:

import os
import sys
import Image
import time
import ImageGrab
import numpy


sd='C:\Users\Saurabh\Desktop'

img=ImageGrab.grab()
imgarr=numpy.asarray(img)
print imgarr
img2=Image.fromarray(numpy.uint8(imgarr))
sec=time.time()
lc=time.localtime(sec)
t=time.asctime(lc)
print t
strng=""+t[8:10]+"_"+t[11:13]+"_"+t[14:16]+"_"+t[17:19]
saveas=os.path.join(sd, 'ScreenShot_'+strng+'.jpg')
#img.save(saveas)
img2.save(saveas)
print "run successful"

Answer 1

Well I also have been working on this problem and figured out that you can send an image over socket by converting it into numpy array.

Here's the sample code-

#Host Side script
#Host will be sending the screen to client.

import numpy as np 
import socket
from PIL import ImageGrab

filename = 'host_data.npy'

print("started.\nListening for connections...")
s = socket.socket()
s.bind((socket.gethostname(), 1234))
s.listen(0)

conn, addr = s.accept()
print('connection established.')

img = np.array(ImageGrab.grab())
np.save(filename, img)
file = open(filename, 'rb')
data = file.read(1024)
conn.send(data)

while data != b'':
    data = file.read(1024)
    conn.send(data)

print('data has been successfully transmitted.')

#This is client side script

import socket
import numpy as np 
import cv2

s = socket.socket()
s.connect((socket.gethostname(), 1234))
print("connected.")

filename = 'client_data.npy'
file = open(filename, 'wb')

data = s.recv(1024)
file.write(data)

while data != b'':
    data = s.recv(1024)
    file.write(data)
file.close()

o_file = np.load(filename)
o_file = cv2.cvtColor(o_file, cv2.COLOR_BGR2RGB)
cv2.imshow('transferred file', o_file)
cv2.waitKey(0)

All I did is, save the numpy array in npy file using np.save(filename) and send the contents of the npy files in bytes format. Then the Client received the contents and made another file of type npy and loaded the array.