한국어
[Python] TCP image socket 구현하기(Server, Client)
게시: 2021년 1월 27일
python
OpenCV
image socket
socket
TCP
1. 서론
작년에 진행한 교차로 보행자 안전 알리미 프로젝트에서 Raspberry pi4와 인공지능 서버 사이의 TCP image socket을 구현했다. 실시간 영상 및 비디오 영상을 OpenCV를 사용하여 프레임 단위로 송수신하는 socket을 구현했다. 만약 Raspberry pi를 이용한다면 OpenCV 설치법이 좀 복잡해서 이 포스팅을 참고하길 바란다.
2. TCP image socket Server
TCP socket으로 이미지를 송수신할 때 가장 중요한 것은 클라이언트에서 서버로 해당 이미지 데이터의 크기를 같이 보내는 것이다. TCP socket을 사용해서 한 번에 보낼 수 있는 데이터의 크기는 제한되어 있으므로 이미지 데이터를 string으로 변환해서 보낼 때 이 크기가 얼마나 큰 지가 중요하다. 따라서, 이미지의 크기를 먼저 받고 그 크기만큼만 socket에서 데이터를 받아서 다시 이미지 데이터의 형태로 변환해야 한다.
class ServerSocket:
def __init__(self, ip, port):
self.TCP_IP = ip
self.TCP_PORT = port
self.socketOpen()
self.receiveThread = threading.Thread(target=self.receiveImages)
self.receiveThread.start()
def socketClose(self):
self.sock.close()
print(u'Server socket [ TCP_IP: ' + self.TCP_IP + ', TCP_PORT: ' + str(self.TCP_PORT) + ' ] is close')
def socketOpen(self):
self.sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
self.sock.bind((self.TCP_IP, self.TCP_PORT))
self.sock.listen(1)
print(u'Server socket [ TCP_IP: ' + self.TCP_IP + ', TCP_PORT: ' + str(self.TCP_PORT) + ' ] is open')
self.conn, self.addr = self.sock.accept()
print(u'Server socket [ TCP_IP: ' + self.TCP_IP + ', TCP_PORT: ' + str(self.TCP_PORT) + ' ] is connected with client')
def receiveImages(self):
try:
while True:
length = self.recvall(self.conn, 64)
length1 = length.decode('utf-8')
stringData = self.recvall(self.conn, int(length1))
stime = self.recvall(self.conn, 64)
print('send time: ' + stime.decode('utf-8'))
now = time.localtime()
print('receive time: ' + datetime.utcnow().strftime('%Y-%m-%d %H:%M:%S.%f'))
data = numpy.frombuffer(base64.b64decode(stringData), numpy.uint8)
decimg = cv2.imdecode(data, 1)
cv2.imshow("image", decimg)
cv2.waitKey(1)
except Exception as e:
print(e)
self.socketClose()
cv2.destroyAllWindows()
self.socketOpen()
self.receiveThread = threading.Thread(target=self.receiveImages)
self.receiveThread.start()
def recvall(self, sock, count):
buf = b''
while count:
newbuf = sock.recv(count)
if not newbuf: return None
buf += newbuf
count -= len(newbuf)
return buf
def main():
server = ServerSocket('localhost', 8080)
if __name__ == "__main__":
main()3. TCP image socket Client
3-1. cam 송신
Client에서는 Server에 이미지 데이터를 전송할 때 해당 이미지 데이터의 크기 정보를 같이 넘겨줘야 한다.
class ClientSocket:
def __init__(self, ip, port):
self.TCP_SERVER_IP = ip
self.TCP_SERVER_PORT = port
self.connectCount = 0
self.connectServer()
def connectServer(self):
try:
self.sock = socket.socket()
self.sock.connect((self.TCP_SERVER_IP, self.TCP_SERVER_PORT))
print(u'Client socket is connected with Server socket [ TCP_SERVER_IP: ' + self.TCP_SERVER_IP + ', TCP_SERVER_PORT: ' + str(self.TCP_SERVER_PORT) + ' ]')
self.connectCount = 0
self.sendImages()
except Exception as e:
print(e)
self.connectCount += 1
if self.connectCount == 10:
print(u'Connect fail %d times. exit program'%(self.connectCount))
sys.exit()
print(u'%d times try to connect with server'%(self.connectCount))
self.connectServer()
def sendImages(self):
cnt = 0
capture = cv2.VideoCapture(0)
capture.set(cv2.CAP_PROP_FRAME_WIDTH, 480)
capture.set(cv2.CAP_PROP_FRAME_HEIGHT, 315)
try:
while capture.isOpened():
ret, frame = capture.read()
resize_frame = cv2.resize(frame, dsize=(480, 315), interpolation=cv2.INTER_AREA)
now = time.localtime()
stime = datetime.utcnow().strftime('%Y-%m-%d %H:%M:%S.%f')
encode_param=[int(cv2.IMWRITE_JPEG_QUALITY),90]
result, imgencode = cv2.imencode('.jpg', resize_frame, encode_param)
data = numpy.array(imgencode)
stringData = base64.b64encode(data)
length = str(len(stringData))
self.sock.sendall(length.encode('utf-8').ljust(64))
self.sock.send(stringData)
self.sock.send(stime.encode('utf-8').ljust(64))
print(u'send images %d'%(cnt))
cnt+=1
time.sleep(0.095)
except Exception as e:
print(e)
self.sock.close()
time.sleep(1)
self.connectServer()
self.sendImages()
def main():
TCP_IP = 'localhost'
TCP_PORT = 8080
client = ClientSocket(TCP_IP, TCP_PORT)
if __name__ == "__main__":
main()3-2. local video 송신
Client에서는 Server에 이미지 데이터를 전송할 때 해당 이미지 데이터의 크기 정보를 같이 넘겨줘야 한다.
class ClientVideoSocket:
def __init__(self, ip, port, video_path):
self.TCP_SERVER_IP = ip
self.TCP_SERVER_PORT = port
self.video_path = video_path
self.connectCount = 0
self.connectServer()
def connectServer(self):
try:
self.sock = socket.socket()
self.sock.connect((self.TCP_SERVER_IP, self.TCP_SERVER_PORT))
print(u'Client socket is connected with Server socket [ TCP_SERVER_IP: ' + self.TCP_SERVER_IP + ', TCP_SERVER_PORT: ' + str(self.TCP_SERVER_PORT) + ' ]')
self.connectCount = 0
self.sendImages()
except Exception as e:
print(e)
self.connectCount += 1
if self.connectCount == 10:
print(u'Connect fail %d times. exit program'%(self.connectCount))
sys.exit()
print(u'%d times try to connect with server'%(self.connectCount))
time.sleep(1)
self.connectServer()
def sendImages(self):
cnt = 0
capture = cv2.VideoCapture(self.video_path)
capture.set(cv2.CAP_PROP_FRAME_WIDTH, 480)
capture.set(cv2.CAP_PROP_FRAME_HEIGHT, 315)
try:
while capture.isOpened():
ret, frame = capture.read()
resize_frame = cv2.resize(frame, dsize=(480, 315), interpolation=cv2.INTER_AREA)
now = time.localtime()
stime = datetime.utcnow().strftime('%Y-%m-%d %H:%M:%S.%f')
encode_param=[int(cv2.IMWRITE_JPEG_QUALITY),90]
result, imgencode = cv2.imencode('.jpg', resize_frame, encode_param)
data = numpy.array(imgencode)
stringData = base64.b64encode(data)
length = str(len(stringData))
self.sock.sendall(length.encode('utf-8').ljust(64))
self.sock.send(stringData)
self.sock.send(stime.encode('utf-8').ljust(64))
print(u'send images %d'%(cnt))
cnt+=1
time.sleep(0.02)
except Exception as e:
print(e)
self.sock.close()
time.sleep(1)
self.connectServer()
self.sendImages()
def main():
TCP_IP = 'localhost'
TCP_PORT = 8080
video_path = './big_buck_bunny_720p_10mb.mp4'
client = ClientVideoSocket(TCP_IP, TCP_PORT, video_path)
if __name__ == "__main__":
main()