1. 源由

最近，打算在Companion Computer上一些目标识别的算法，最流行、最基础的可能就是OpenCV了。

首先，将算法在x86的laptop上跑起来，将目标识别程序运行起来，基本的功能实现。

然后，基于Linux系统移植到Companion Computer上就会简单很多。

2. 验证环境

准备以下验证环境：

• x86-64bit laptop x 1
• ubuntu 22.04 jammy
• OpenCV 4.9.0 (latest release)

$ lsb_release  -a
No LSB modules are available.
Distributor ID: Ubuntu
Description:    Ubuntu 22.04.3 LTS
Release:        22.04
Codename:       jammy$ tree -L 1
.
├── opencv
├── opencv_contrib
├── opencv-4.9.0-py3
├── opencv-4.9.0.zip
└── opencv_contrib-4.9.0.zip

3. OpenCV安装

目前，最新的OpenCV发行版本: 4.9.0

• opencv-4.9.0
• opencv_contrib-4.9.0

### Define OpenCV Version to install 
cvVersion="4.9.0"### Save current working directory
SNAPDRAGONFLY_CURRENT_DIR_PATH=$(pwd)SNAPDRAGONFLY_CURRENT_OPENCV=opencv
SNAPDRAGONFLY_CURRENT_OPENCV_CONTRIB=opencv_contribSNAPDRAGONFLY_CURRENT_OPENCV_ZIP=opencv-$cvVersion.zip
SNAPDRAGONFLY_CURRENT_OPENCV_CONTRIB_ZIP=opencv_contrib-$cvVersion.zip

3.1 系统升级

除了必备的组件外，更新了一些常用的工具，比如：tree, aptitude 。

sudo add-apt-repository "deb http://security.ubuntu.com/ubuntu jammy-security main" -y
sudo apt -y update
sudo apt -y upgrade### Install dependencies
sudo apt -y install unzip locate tree aptitude
sudo apt -y install build-essential checkinstall cmake pkg-config yasm
sudo apt -y install git gfortran
sudo apt -y install libjpeg8-dev libpng-dev libjpeg-dev libgtk-3-dev 
sudo apt -y install software-properties-common
sudo apt -y install libtiff-dev
sudo apt -y install libavcodec-dev libavformat-dev libswscale-dev libdc1394-dev
sudo apt -y install libxine2-dev
sudo apt -y install libgstreamer1.0-dev libgstreamer-plugins-base1.0-dev
sudo apt -y install libgtk2.0-dev libtbb-dev libtbb2
sudo apt -y install openexr libopenexr-dev python3-numpy### qt5-default dependencies
sudo apt -y install libatlas-base-dev
sudo apt -y install libfaac-dev libmp3lame-dev libtheora-dev
sudo apt -y install libvorbis-dev libxvidcore-dev
sudo apt -y install libopencore-amrnb-dev libopencore-amrwb-dev libavro-dev
sudo apt -y install x264 libx264-dev v4l-utils
sudo apt -y install qtcreator qtbase5-dev qt5-qmake cmake### Optional dependencies
sudo apt -y install libprotobuf-dev protobuf-compiler
sudo apt -y install libgoogle-glog-dev libgflags-dev
sudo apt -y install libgphoto2-dev libeigen3-dev libhdf5-dev doxygen### Special dependencies
sudo apt -y install libv4l-dev
cd /usr/include/linux
sudo ln -s -f ../libv4l1-videodev.h videodev.h

注：本次系统采用的Ubuntu 22.04.3 LTS，所以使用了jammy-security源，请大家根据实际情况调整。

3.2 Python安装

使用Python虚拟环境，方便切换(笔者这里也有一些本地环境，为了避免相互干扰，虚拟Python环境会更好些)。

sudo apt -y install python3-dev python3-pip
sudo apt -y install python3-testresources
sudo apt -y install python3.10-venv### create virtual environment
python3 -m venv opencv-"$cvVersion"-py3
echo "# Virtual Environment Wrapper" >> ~/.bashrc
echo "alias workoncv-$cvVersion=\"source $SNAPDRAGONFLY_CURRENT_DIR_PATH/opencv-$cvVersion-py3/bin/activate\"" >> ~/.bashrc### enter virtual environment
source "$SNAPDRAGONFLY_CURRENT_DIR_PATH"/opencv-"$cvVersion"-py3/bin/activate### install python libraries within this virtual environment
pip install -r requirements.txt### quit virtual environment
deactivate

3.3 OpenCV C/C++环境安装

这里的命令含有部分脚本变量。如果大家copy下来，实际上是可以直接脚本运行的。

但是，国内环境复杂多变，如果顺序执行的脚本搞不定，还请一行一行手动执行。

注：后续有时间，会整理一些基本安装脚本，方便大家学习使用。

# https://github.com/opencv/opencv.git
wget https://github.com/opencv/opencv/archive/refs/tags/$cvVersion.zip
mv $cvVersion.zip $SNAPDRAGONFLY_CURRENT_OPENCV_ZIP
unzip $SNAPDRAGONFLY_CURRENT_OPENCV_ZIP
mv opencv-$cvVersion opencv# https://github.com/opencv/opencv_contrib.git
wget https://github.com/opencv/opencv_contrib/archive/refs/tags/$cvVersion.zip
mv $cvVersion.zip $SNAPDRAGONFLY_CURRENT_OPENCV_CONTRIB_ZIP
unzip $SNAPDRAGONFLY_CURRENT_OPENCV_CONTRIB_ZIP
mv opencv_contrib-$cvVersion opencv_contrib### Clean build directories
rm -rf opencv/build
rm -rf opencv_contrib/build### Build opencv
cd opencv
mkdir build
cd buildcmake -D CMAKE_BUILD_TYPE=RELEASE \-D WITH_TBB=ON \-D BUILD_TBB=OFF \-D WITH_V4L=ON \-D WITH_QT=ON \-D WITH_OPENGL=ON \-D OPENCV_GENERATE_PKGCONFIG=ON \-D INSTALL_PYTHON_EXAMPLES=ON \-D INSTALL_C_EXAMPLES=ON \-D OPENCV_PYTHON3_INSTALL_PATH=$SNAPDRAGONFLY_CURRENT_DIR_PATH/opencv-$cvVersion-py3/lib/python3.10/site-packages \-D OPENCV_ENABLE_NONFREE=ON \-D OPENCV_EXTRA_MODULES_PATH=../../opencv_contrib/modules \-D PYTHON_EXECUTABLE=../../opencv-$cvVersion-py3/bin/python3 \-D BUILD_EXAMPLES=ON ..make -j$(nproc)
make install

3.4 OpenCV Python虚拟环境安装

$ cp opencv/build/lib/python3/cv2.cpython-310-x86_64-linux-gnu.so opencv-4.9.0-py3/lib/python3.10/site-packages/cv2/cv2.so

3.5 OpenCV检查

大致看到下面输出，系统里面应该基本就安装好了。

• C/C++环境

$ pkg-config --modversion opencv4
4.9.0

• Python虚拟环境

$ workoncv-4.9.0
(opencv-4.9.0-py3) daniel@daniel-ThinkPad-SL410:~/OpenCV$ ipython
Python 3.10.12 (main, Nov 20 2023, 15:14:05) [GCC 11.4.0]
Type 'copyright', 'credits' or 'license' for more information
IPython 8.21.0 -- An enhanced Interactive Python. Type '?' for help.In [1]: import cv2In [2]: print(cv2.__version__)
4.9.0In [3]: quit
(opencv-4.9.0-py3) daniel@daniel-ThinkPad-SL410:~/OpenCV$ deactivate

4. 总结

笔者整理这份资料是搞了好几天的，遇到不少坑。

主要就是折腾在OpenCV开发环境不熟悉，网络复杂多变等问题上。希望整理出来，方便交流学习！

• Github操作网络异常笔记
• apt-get通过代理更新系统

补充：3.3章需要可能需要代理，具体情况请根据实际网络进行配置。

$ git config --global https.proxy http://192.168.1.13:808
$ export https_proxy=http://192.168.1.13:808

5. 参考资料

【1】ubuntu22.04@laptop 常用基础环境安装
【2】ubuntu22.04@laptop安装&配置VNC服务端
【3】ArduPilot开源代码之CompanionComputer上天计划

6. 补充 - python环境

之前发现python3环境下，cv2输出4.5.4，没有理解。后面发现该4.5.4是ubuntu deb安装包的版本。

$ python3 -c "import cv2; print(cv2.__version__)"
4.5.4