MacOS下OpenCV + Python+PyQt5 多进程Bug

MacOS下OpenCV + Python+PyQt5 多进程Bug

环境

• macOS Catalina 10.15.7
• pyqt5
• opencv

问题

• 多进程情况下cv2.resize或者cv2.cvtColor引发程序崩溃
• 使用PyQt5与opencv的冲突

可能的解决方案

1. 安装opencv-python-headless替换opencv-python
2. 设置 cv2.setNumThreads(0)

OpenCV will try to set the number of threads for the next parallel region. If threads == 0, OpenCV will disable threading optimizations and run all its functions sequentially. Passing threads < 0 will reset threads number to system default. This function must be called outside of parallel region.

3. import multiprocessing as mp
   mp.set_start_method('spawn')
   

参考

OpenCV + Python multiprocessing breaks on OSX

pytorch dataloader stucked if using opencv resize method

OpenCV 4.4.0.44 macOS Catalina - Hang/Frozen