python+openCV安装过程常见错误解决办法以及工具包下载_opencv-python==4.7.0.72

常见解决办法

错误一：you are using pip version ** howerver version ** is available.
you should consider upgrading via the ‘python -m pip install --upgrade pip’ command.
键入 'python -m pip install --upgrade pip’依旧出错
解决办法：在命令窗口运行pip install opencv-python 后重试

错误二：Could not find a version that satisfies the requirement openCV (from versions: ) No matching distribution found for openCV；Traceback (most recent call last): File “”, line 1, in Module
解决办法：
因为最新python在pip库没有匹配的版本，所以使用pip安装会报错
Could not find a version that satisfies the requirement opencv (from versions: )
No matching distribution found for opencv
因此，到这儿去下载opencv
http://www.lfd.uci.edu/~gohlke/pythonlibs/
选择opencv_python-4.0.1-cp37-cp37m-win_amd64.whl
拷贝opencv_python-4.0.1-cp357cp37m-