python+opencv实现文件的读取

Question

想实现局域网下不同设备的视频流通信，决定采用socket实现，由于socket无法直接实现图片通讯，采用将编码的字符串写入文件再读取写出拿来模拟socket通信，在解码端代码一直报bug，请求指点

编码段

import cv2
import win32gui 
from PIL import ImageGrab
import numpy as np

im = cv2.imread('bus.jpg')
img_encode = cv2.imencode('.jpg', im，[cv.IMWRITE_JPEG_QUALITY, 50])[1]
data_encode = np.array(img_encode)
image_binary = data_encode.tobytes()  # transform bytes stream
#send_data = "send".encode('utf-8') + (len(image_binary)).to_bytes(4, byteorder='little') + image_binary
send_data=str(image_binary)

with open('img_encode.txt', 'w') as f:
    f.write(send_data)
    f.flush

解码端

import cv2
import numpy as np


with open('img_encode.txt', 'r') as f:
    str_encode = f.read()

str_encode = bytes(str_encode,encoding='utf-8')
image_np = np.frombuffer(str_encode, np.uint8)  # transform image to np.uint8 format
image = cv2.imdecode(image_np, cv2.IMREAD_COLOR)  # decode image to the type of opencv
cv2.imshow("img_decode",image)
cv2.waitKey(0)

报错内容

Traceback (most recent call last):
  File "C:\Users\pc\Desktop\new\decode.py", line 11, in <module>
    cv2.imshow("img_decode",image)
cv2.error: OpenCV(4.5.4) D:\a\opencv-python\opencv-python\opencv\modules\imgproc\src\color.cpp:182: error: (-215:Assertion failed) !_src.empty() in function 'cv::cvtColor'

Answer 1

缩进？
你缩进不对的话就会导致你的str——encode是空的，这也就是报错里面提示你说图片为空不能imshow