安装成功后可以使用相应的名称进入相应的版本，会详细的显示版本信息。
pip3安装
opencv
-
python
先把ubuntu 中
python
版本默认设置为：
python
3
分别执行两行命令即可
echo alias
python
=
python
3 >> ~/.bashrc
source ~/.bashrc
如果ubuntu中没有pip 的，先安装pip
sudo apt-get install
python
3-pip
②由于一般要下载30min左右，有时会误认为是卡死，此时需要用--verbose 进行安装命令跟踪安装过程，可以在每一行最前端显示安装百分比：pip install
opencv
-
python
-i https://pypi.tuna.ts
ing
hua.edu.cn/simple --verbose ，之后耐心等待即可。①更新pip版本：pip install --upgrade pip ，之后再次尝试。
已解决ERROR:
Failed
build
ing
wheel
for
opencv
-
python
-headless
Failed
to
build
opencv
-
python
-headless
ERROR: Could not
build
wheel
s for
opencv
-
python
-headless, which is required to install pyproject.toml-based projects报错信息亲测有效
在按照requirements.txt安装依赖包时，使用命令pip3 install -r requirements遇到了两个错误，分别是
Failed
build
ing
wheel
for llvmlite，
Failed
build
ing
wheel
for
opencv
-
python
（解决过程中忘记截图了，本文中出现的一些图来自其它博客）
1.
Failed
build
ing
wheel
for
opencv
-
python
这个错误的提示信息是
Problem with the CMake ins
最近用树莓派安装
opencv
，按照晚上的教程，apt换清华源，pip换清华源，apt安装一堆依赖，发现提示找不到和libqt4相关的包，其实本来就没必要安装，它们已经被取代了。
然后进入喜闻乐见的pip3安装
opencv
-
python
的环节，经过数小时的等待，发现cmake安装失败。。。仔细看会发现是卡在
wheel
编译那里，往上翻翻看看他是要安装cmake3.22.4，于是想着去apt安装cmake，apt-cache show cmake发现最新版是3.18.x，于是想着去cmake官网下载3.22.4
C:\Users\EDY>pip install -i https://pypi.tuna.ts
ing
hua.edu.cn/simple
opencv
-
python
Look
ing
in indexes: https://pypi.tuna.ts
ing
hua.edu.cn/simple
Collect
ing
opencv
-
python
Download
ing
https://pypi.tuna.ts
ing
hua.edu.cn/packages/c4/e2/27a153e27b98410cf5a87.
关于Could not
build
wheel
s for
opencv
-
python
-headless, which is...报错的解决方案，在通过最新版pip在线安装package：
opencv
-
python
-headless的时候，会产生报错信息，主要为ERROR:
Failed
build
ing
wheel
for
opencv
-
python
-headless；ERROR: Could not
build
wheel
s for
opencv
-
python
-headless, which is
已解决 ERROR:
Failed
build
ing
wheel
for
opencv
-
python
-headless
Failed
to
build
opencv
-
python
-headless
ERROR: Could not
build
wheel
s for
opencv
-
python
-headless, which is required to install pyproject.toml-based projects报错信息亲测有效
