树莓派4安装opencv

学习记录

〇、环境

1. 树莓派4B
2. Raspberry Pi OS
   下载地址：Download Raspberry Pi OS for Raspberry Pi
   Raspberry Pi OS (32-bit) with desktop and recommended software
   Image with desktop and recommended software based on Debian Buster
   Version:May 2020
   Release date:2020-05-27
   Kernel version:4.19
   Size:2523 MB
   Release notes
   Download TorrentDownload ZIP
   SHA-256:fdbd6f5b5b7e1fa5e724bd8747c5109801442e9200144d0a1941c9e73c93dd61
3. opencv 4.3.0-dev

一、树莓派基本配置

1. 烧录镜像

使用SDFormatter格式化SD卡，使用Win32DiskImager烧录镜像

2. 开SSH

在boot路径下新建SSH空文件

3. 开机

插卡上电开机，接入网线，通过路由器查询IP，使用xshell的ssh连接树莓派。
用户名 pi
密码 raspberry

4. 开VNC

sudo raspi-config
打开VNC，设置分辨率，重启
开启图形化时代

5. 开机设置

设置国家，中国，汉语，上海
设置密码
填充屏幕
选择wifi
更新（建议跳过，换源后更新）
可能要重启

6. 换源

备份原文件

sudo cp /etc/apt/sources.list /etc/apt/sources.list.bak

sudo cp /etc/apt/sources.list.d/raspi.list /etc/apt/sources.list.d/raspi.list.bak

换源1

sudo nano /etc/apt/sources.list

deb http://mirrors.tuna.tsinghua.edu.cn/raspbian/raspbian/ buster main contrib non-free rpi
deb-src http://mirrors.tuna.tsinghua.edu.cn/raspbian/raspbian/ buster main contrib non-free rpi

换源2

sudo nano /etc/apt/sources.list.d/raspi.list

deb http://mirrors.tuna.tsinghua.edu.cn/raspberrypi/ buster main ui
deb-src http://mirrors.tuna.tsinghua.edu.cn/raspberrypi/ buster main ui

更新

sudo apt-get update
sudo apt-get upgrade

7. 安装配置VIM

sudo apt-get install vim
vim /etc/vim/vimrc

添加代码

set nu
set pastetoggle=<F9>

二、OpenCV安装准备

1. 下载相关包

下载地址

https://github.com/opencv/opencv
https://github.com/opencv/opencv_contrib

2. 将下载好的文件复制到树莓派

新建文件夹

mkdir ~/opencv_build

将下载好的文件复制到树莓派并解压

路径为：
~/opencv_build/opencv
~/opencv_build/opencv_contrib

3. 增加交换空间

增加交换空间以避免因内存问题导致的编译挂起

sudo vim /etc/dphys-swapfile

第16行，将 CONF_SWAPSIZE 值从默认值更改 100 为 1024 ：
运行以下命令以使更改生效

sudo /etc/init.d/dphys-swapfile restart

4.安装相关依赖包

sudo apt install build-essential cmake git pkg-config libgtk-3-dev libcanberra-gtk*
sudo apt install libavcodec-dev libavformat-dev libswscale-dev libv4l-dev libxvidcore-dev libx264-dev
sudo apt install libjpeg-dev libpng-dev libtiff-dev gfortran openexr libatlas-base-dev opencl-headers
sudo apt install python3-dev python3-numpy libtbb2 libtbb-dev libdc1394-22-dev

5. 创建build目录

mkdir -p ~/opencv_build/opencv/build
cd ~/opencv_build/opencv/build

三、安装OpenCV

1. 设置编译参数

命令行输入

cmake -D CMAKE_BUILD_TYPE=RELEASE \
    -D CMAKE_INSTALL_PREFIX=/usr/local \
    -D INSTALL_C_EXAMPLES=OFF \
    -D INSTALL_PYTHON_EXAMPLES=OFF \
    -D OPENCV_GENERATE_PKGCONFIG=ON \
    -D ENABLE_NEON=ON \
    -D ENABLE_VFPV3=ON \
    -D BUILD_TESTS=OFF \
    -D OPENCV_ENABLE_NONFREE=ON \
    -D OPENCV_EXTRA_MODULES_PATH=~/opencv_build/opencv_contrib/modules \
    -D BUILD_EXAMPLES=OFF ..

需要运行一小会
运行结果

-- Configuring done
-- Generating done
-- Build files have been written to: /home/pi/opencv_build/opencv/build

2. 编译

make -j4

这个过程需要2-3小时
中间可能会报错，如图所示

将boostdesc_bgm.i等文件拷贝到下列路径

~/opencv_build/opencv_contrib/modules/xfeatures2d/src

再次编译

make -j4

继续之前的编译

---

结果为

[100%] Linking CXX executable ../../bin/opencv_perf_optflow
[100%] Built target opencv_perf_optflow
[100%] Linking CXX executable ../../bin/opencv_perf_superres
[100%] Built target opencv_perf_superres
[100%] Linking CXX shared module ../../lib/cv2.so
[100%] Built target opencv_python2
[100%] Linking CXX shared module ../../lib/python3/cv2.cpython-37m-arm-linux-gnueabihf.so
[100%] Built target opencv_python3

安装已编译的文件

sudo make install

很快结束，结果为

-- Installing: /usr/local/bin/opencv_interactive-calibration
-- Set runtime path of "/usr/local/bin/opencv_interactive-calibration" to "/usr/local/lib"
-- Installing: /usr/local/bin/opencv_version

3. 检查安装结果

C++库，命令行输入

pkg-config --modversion opencv4

结果为

4.3.0

Python库，命令行输入

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

结果为

4.3.0-dev

4. 收尾

可以删除OpenCV包

rm -rf ~/opencv_build

将交换空间更改回原始大小：
将1024改回100

sudo vim /etc/dphys-swapfile

使修改生效

sudo /etc/init.d/dphys-swapfile restart