安装cmake3：
echo '[group_kdesig-cmake3_EPEL]
name=Copr repo for cmake3_EPEL owned by @kdesig
baseurl=https://copr-be.cloud.fedoraproject.org/results/@kdesig/cmake3_EPEL/epel-7-$basearch/
type=rpm-md
skip_if_unavailable=True
gpgcheck=1
gpgkey=https://copr-be.cloud.fedoraproject.org/results/@kdesig/cmake3_EPEL/pubkey.gpg
repo_gpgcheck=0
enabled=1
enabled_metadata=1' >> /etc/yum.repos.d/cmake3.repo
yum -y install cmake3
安装gcc：
yum -y install epel-release
yum -y install gcc gcc-c++
yum -y install cmake
yum -y install python-devel numpy
yum -y install gtk2-devel
yum -y install libdc1394-devel
yum -y install libv4l-devel
yum -y install gstreamer-plugins-base-devel
安装ffmpeg：
sudo rpm –import /etc/pki/rpm-gpg/RPM-GPG-KEY-EPEL-7
yum repolist
sudo rpm –import http://li.nux.ro/download/nux/RPM-GPG-KEY-nux.ro
sudo rpm -Uvh http://li.nux.ro/download/nux/dextop/el7/x86_64/nux-dextop-release-0-1.el7.nux.noarch.rpm
yum repolist
yum update -y
yum install -y ffmpeg
ffmpeg -version
yum -y install ffmpeg-devel
安装ant：
yum -y install ant
开始编译opencv：
进入opencv解压目录
mkdir build
cd build
cmake3 -D CMAKE_BUILD_TYPE=RELEASE -D CMAKE_INSTALL_PREFIX=/opencv-3.4.1/install -D BUILD_TESTS=OFF ..
make
sudo make install
到此安装成功，可以到./build/bin目录下查看是否有opencv-341.jar生成
如果有，说明安装成功了；还可以到./build/lib目录下查看是否有libopencv_java341.so生成
opencv for java环境配置：
/bin/bash -c 'echo "/opencv-3.4.1/install/lib64" > /etc/ld.so.conf.d/opencv.conf'
ldconfig