Python OpenCV线程
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Python脚本从套接字读取png图像,然后尝试使用OpenCV显示慢速视频。有两个类server.py和Worker.py。 Server.py从套接字接收原始png并将其放在队列中。在自己的线程中,工作人员将png出列并显示它。只有第一张图像正确显示。其他图像不是可见的(即第一个图像保留),但调用ShowImage和WaitKey。
线程模型是对的吗?似乎服务器套接字线程阻止OpenCV线程显示。有没有办法将服务器套接字放在后台线程上?从后台线程调用ShowWIndow和WaitKey是否正确?我对Mac上的Python或OpenCV线程知之甚少。任何意见和建议将不胜感激。
server.朋友:
#! /usr/bin/env python
import sys
import SocketServer
import socket
import subprocess
import time
import cv
import Worker
import ShowImage
HOST = 'andrew-rosenblums-macbook-pro.local'
PORT = 3001
FRAME_SIZE = 144*192
data = ''
worker = Worker.Worker()
class SingleTCPHandler(SocketServer.BaseRequestHandler):
imagesSaved = 0
"One instance per connection. Override handle(self) to customize action."
def handle(self):
# self.request is the client connection
print "connection received.."
while True:
#print "calling rcv"
messageLength = self.request.recv(6) # Read 6 ascii char image size
cv.WaitKey(30)
if (len(messageLength) > 0):
print "messageLength=" + messageLength
iLength = int(messageLength)
message = ''
while (iLength > 0):
if (iLength > 1024):
chunk = self.request.recv(1024)
else:
chunk = self.request.recv(iLength)
iLength -= len(chunk)
message += chunk
print "rcvd imsg of len=" + str(len(message))
worker.write(message)
if (SingleTCPHandler.imagesSaved == 0):
SingleTCPHandler.imagesSaved += 1
print "closing stream"
self.request.close()
print "done receiving"
def finish(self):
print "finish called"
class SimpleServer(SocketServer.ThreadingMixIn, SocketServer.TCPServer):
# Ctrl-C will cleanly kill all spawned threads
daemon_threads = True
# much faster rebinding
allow_reuse_address = True
def __init__(self, server_address, RequestHandlerClass):
SocketServer.TCPServer.__init__(self, server_address, RequestHandlerClass)
if __name__ == "__main__":
server = SimpleServer((HOST, PORT), SingleTCPHandler)
# terminate with Ctrl-C
try:
print "waiting for connections..."
server.serve_forever()
except KeyboardInterrupt:
sys.exit(0)
worker.朋友
#! /usr/bin/env python
import time
from threading import Thread
from Queue import Queue
import sys
import cv
import cv2
import numpy as np
import Image
from cStringIO import StringIO
class Worker(Thread):
count = 0
def __init__(self):
Thread.__init__(self)
self.cvImage = None
cv.NamedWindow('display')
cv.MoveWindow('display', 10, 10)
self.queue = Queue()
self.writer = None
# Daemon threads won't prevent process from exiting
self.setDaemon(True)
# Start ourselves automatically
self.start()
print "Worker started"
def run(self):
writer = None
while 1:
frame = None
try:
#frame = self.queue.get(block=False)
frame = self.queue.get()
print "display izeof rawImage=" + str(len(frame))
#convert to mat
pilImage = Image.open(StringIO(frame));#.convert("RGB");
bgrImage = np.array(pilImage)
cvBgrImage = cv.fromarray(bgrImage)
self.cvImage = cv.CreateImage(cv.GetSize(cvBgrImage),8,3)
cv.CvtColor(cvBgrImage, self.cvImage, cv.CV_BGR2RGB)
#show it
cv.ShowImage('display', self.cvImage)
cv.WaitKey(30)
self.cvImage = None
except:
frame = None
print "done with thread"
# Requests from main thread
def write(self, frame):
self.queue.put(frame)
def stop(self):
self.queue.put(None)
答案
答案很简单:OpenCV的ShowImage
和WaitKey
必须在主线程中。我猜这是GUI线程。 ServerSockets被推送到自己的线程,这在Python中非常容易。
您只需要:
UDPThread = Thread(target = UDPServer.run)
s.start(UPDThread)
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