この記事はOpenCV Advent Calendar 2020の16日目の代打記事です．
時空列がゆがんでいますが、まあ気にせず！！
TL;DR
- OpenCV4 と OpenCV5の共存はめんどくさいです。
-
CMAKE_INSTALL_PREFIXでインストール先をずらす。 -
export PKG_CONFIG_PATH=/usr/local_opencv5/lib/pkgconfigでpkg-configにopencv5.pcの場所を教える。 -
export LD_LIBRARY_PATH=$LD_LIBRARY_PATH:/usr/local_opencv5/libで実行時にshared libraryの場所を教える。
-
以上です！
pkg-configが使えるオプションを有効化しています（ポイント★）
昔ながらの人なので、pkg-configでコンパイル時指定をやってます。そういう人向けの説明ですね……
cmake 派の方は…
@dandelion1124 先生から、CMakeを使っている方は、CMAKE_INSTALL_PREFIXを変える＋OpenCV_DIRの指定切り替えでやると良いとのことです！
ありがとうございました！（Qiitaの謎ルールが明らかになった）記事のやつはCMake使っているのであればCMAKE_INSTALL_PREFIXでインストール先を変えて、OpenCV使う側ではOpenCV_DIRで所望のOpenCVバージョンのパスを指定するのでもよさそうです。
— dandelion (@dandelion1124) December 19, 2020
はじめに
「OpenCVのputText()関数が、next branch(OpenCV5)でどうやらTrueTypeになるらしい！」と聞いたので、
さっそく画像をだしてみようと思いました。
なのですが、同じタイミングで、OpenCV4とOpenCV5それぞれをリンクした実行ファイルの結果が同じになってしまった」ので、なんだこれーと調査をしました。
最初の状態
OpenCVがインストールされていない環境を用意します。
kmtr@ubuntu2010:~/work$ pkg-config --list-all | grep open
caf-openmpi CAF - Co-Array Fortran support
hdf5 HDF5 - Hierarchical Data Format 5 (HDF5) - openmpi version
hdf5-mpi HDF5 - Hierarchical Data Format 5 (HDF5) - openmpi version
hdf5-openmpi HDF5 - Hierarchical Data Format 5 (HDF5) - openmpi version
libevent_openssl libevent_openssl - libevent_openssl adds openssl-based TLS support to libevent
libopenjp2 openjp2 - JPEG2000 library (Part 1 and 2)
libopenjp3d openjp3d - JPEG2000 Extensions for three-dimensional data (Part 10)
libopenjpip openjpip - JPEG2000 Interactivity tools, APIs and protocols (Part 9)
opengl OpenGL - OpenGL (without GLX) library and headers.
openssl OpenSSL - Secure Sockets Layer and cryptography libraries and tools
OpenCV 4.5.0 をインストールしてみる。
kmtr@ubuntu2010:~/work/opencv-4.5.0/build$ pkg-config --list-all | grep open
caf-openmpi CAF - Co-Array Fortran support
hdf5 HDF5 - Hierarchical Data Format 5 (HDF5) - openmpi version
hdf5-mpi HDF5 - Hierarchical Data Format 5 (HDF5) - openmpi version
hdf5-openmpi HDF5 - Hierarchical Data Format 5 (HDF5) - openmpi version
libevent_openssl libevent_openssl - libevent_openssl adds openssl-based TLS support to libevent
libopenjp2 openjp2 - JPEG2000 library (Part 1 and 2)
libopenjp3d openjp3d - JPEG2000 Extensions for three-dimensional data (Part 10)
libopenjpip openjpip - JPEG2000 Interactivity tools, APIs and protocols (Part 9)
opencv4 OpenCV - Open Source Computer Vision Library
opengl OpenGL - OpenGL (without GLX) library and headers.
openssl OpenSSL - Secure Sockets Layer and cryptography libraries and tools
kmtr@ubuntu2010:~/work/opencv-4.5.0/build$ pkg-config opencv4 --cflags --libs
-I/usr/local/include/opencv4 -L/usr/local/lib -lopencv_gapi -lopencv_highgui -lopencv_ml -lopencv_objdetect -lopencv_photo -lopencv_stitching -lopencv_video -lopencv_calib3d -lopencv_features2d -lopencv_flann -lopencv_videoio -lopencv_imgcodecs -lopencv_imgproc -lopencv_core
4.5.0がはいったまま、nextを入れてみる。
おお、pkg-configを見ると両方が入った！
インクルードパスも分かれている！こりゃ共存できる・・・？
kmtr@ubuntu2010:~/work/opencv_next/build$ pkg-config --list-all | grep open
caf-openmpi CAF - Co-Array Fortran support
hdf5 HDF5 - Hierarchical Data Format 5 (HDF5) - openmpi version
hdf5-mpi HDF5 - Hierarchical Data Format 5 (HDF5) - openmpi version
hdf5-openmpi HDF5 - Hierarchical Data Format 5 (HDF5) - openmpi version
libevent_openssl libevent_openssl - libevent_openssl adds openssl-based TLS support to libevent
libopenjp2 openjp2 - JPEG2000 library (Part 1 and 2)
libopenjp3d openjp3d - JPEG2000 Extensions for three-dimensional data (Part 10)
libopenjpip openjpip - JPEG2000 Interactivity tools, APIs and protocols (Part 9)
opencv4 OpenCV - Open Source Computer Vision Library
opencv5 OpenCV - Open Source Computer Vision Library
opengl OpenGL - OpenGL (without GLX) library and headers.
openssl OpenSSL - Secure Sockets Layer and cryptography libraries and tools
kmtr@ubuntu2010:~/work/opencv_next/build$ pkg-config opencv4 --cflags --libs
-I/usr/local/include/opencv4 -L/usr/local/lib -lopencv_gapi -lopencv_highgui -lopencv_ml -lopencv_objdetect -lopencv_photo -lopencv_stitching -lopencv_video -lopencv_calib3d -lopencv_features2d -lopencv_flann -lopencv_videoio -lopencv_imgcodecs -lopencv_imgproc -lopencv_core
kmtr@ubuntu2010:~/work/opencv_next/build$ pkg-config opencv5 --cflags --libs
-I/usr/local/include/opencv5 -L/usr/local/lib -lopencv_gapi -lopencv_highgui -lopencv_ml -lopencv_objdetect -lopencv_photo -lopencv_stitching -lopencv_video -lopencv_calib3d -lopencv_features2d -lopencv_dnn -lopencv_flann -lopencv_videoio -lopencv_imgcodecs -lopencv_imgproc -lopencv_core
ダメです、（そのままだと）共存できていません。
お気づきでしょうか……
確かに -I/usr/local/include/opencv4と-I/usr/local/include/opencv5 となっているのでヘッダファイルは分かれている。
でも、/usr/local/libなので、ライブラリは…？
kmtr@ubuntu2010:~/work/opencv_next/build$ ls /usr/local/lib/libopen* -al | sort -k 9 | head -10
lrwxrwxrwx 1 root root 24 12月 19 13:13 /usr/local/lib/libopencv_calib3d.so -> libopencv_calib3d.so.5.0
lrwxrwxrwx 1 root root 26 12月 19 13:10 /usr/local/lib/libopencv_calib3d.so.4.5 -> libopencv_calib3d.so.4.5.0
-rw-r--r-- 1 root root 81930880 11月 10 19:33 /usr/local/lib/libopencv_calib3d.so.4.5.0
lrwxrwxrwx 1 root root 26 12月 19 13:13 /usr/local/lib/libopencv_calib3d.so.5.0 -> libopencv_calib3d.so.5.0.0
-rw-r--r-- 1 root root 2739928 12月 2 05:15 /usr/local/lib/libopencv_calib3d.so.5.0.0
lrwxrwxrwx 1 root root 21 12月 19 13:13 /usr/local/lib/libopencv_core.so -> libopencv_core.so.5.0
lrwxrwxrwx 1 root root 23 12月 19 13:10 /usr/local/lib/libopencv_core.so.4.5 -> libopencv_core.so.4.5.0
-rw-r--r-- 1 root root 57626288 11月 10 19:33 /usr/local/lib/libopencv_core.so.4.5.0
lrwxrwxrwx 1 root root 23 12月 19 13:13 /usr/local/lib/libopencv_core.so.5.0 -> libopencv_core.so.5.0.0
-rw-r--r-- 1 root root 17690544 12月 2 05:11 /usr/local/lib/libopencv_core.so.5.0.0
つまり、あとからインストールしたnext(OpenCV5)の設定の方が勝ってしまっていますね……
まあ、使うときに毎回、sudo make installして、libopencv_XXX.soの参照先を書き換えればいいんですが、めどい。
-lopencv_core
⇒ /usr/local/lib/libopencv_core.so
⇒ /usr/local/lib/libopencv_core.so.5.0
⇒ /usr/local/lib/libopencv_core.so.5.0.0
/usr/local/lib/libopencv_core.so.4.5
⇒ /usr/local/lib/libopencv_core.so.4.5.0
じゃあどうすれば共存できるの？（かなり強引な解決策）
CMAKE_INSTALL_PREFIXを書き換えてみると行けるかなー
例えばこの例では、/usr/local_opencv5 という謎prefixをインストール先に指定してみている。
この場合、特殊なprefixを付けたので、pkg-configが困らないように場所を追加してあげる必要がある。
export PKG_CONFIG_PATH=/usr/local_opencv5/lib/pkgconfig
インストールも無事にできた。
kmtr@ubuntu2010:~/work/opencv_next/build$ pkg-config --list-all | grep open
caf-openmpi CAF - Co-Array Fortran support
hdf5 HDF5 - Hierarchical Data Format 5 (HDF5) - openmpi version
hdf5-mpi HDF5 - Hierarchical Data Format 5 (HDF5) - openmpi version
hdf5-openmpi HDF5 - Hierarchical Data Format 5 (HDF5) - openmpi version
libevent_openssl libevent_openssl - libevent_openssl adds openssl-based TLS support to libevent
libopenjp2 openjp2 - JPEG2000 library (Part 1 and 2)
libopenjp3d openjp3d - JPEG2000 Extensions for three-dimensional data (Part 10)
libopenjpip openjpip - JPEG2000 Interactivity tools, APIs and protocols (Part 9)
opencv4 OpenCV - Open Source Computer Vision Library
opencv5 OpenCV - Open Source Computer Vision Library
opengl OpenGL - OpenGL (without GLX) library and headers.
openssl OpenSSL - Secure Sockets Layer and cryptography libraries and tools
ライブラリの配置もばっちり
kmtr@ubuntu2010:~/work/opencv_next/build$ ls /usr/local/lib/libopen* -al | sort -k 9 | head -10
lrwxrwxrwx 1 root root 24 12月 19 13:23 /usr/local/lib/libopencv_calib3d.so -> libopencv_calib3d.so.4.5
lrwxrwxrwx 1 root root 26 12月 19 13:10 /usr/local/lib/libopencv_calib3d.so.4.5 -> libopencv_calib3d.so.4.5.0
-rw-r--r-- 1 root root 81930880 11月 10 19:33 /usr/local/lib/libopencv_calib3d.so.4.5.0
lrwxrwxrwx 1 root root 21 12月 19 13:23 /usr/local/lib/libopencv_core.so -> libopencv_core.so.4.5
lrwxrwxrwx 1 root root 23 12月 19 13:10 /usr/local/lib/libopencv_core.so.4.5 -> libopencv_core.so.4.5.0
-rw-r--r-- 1 root root 57626288 11月 10 19:33 /usr/local/lib/libopencv_core.so.4.5.0
lrwxrwxrwx 1 root root 22 11月 9 22:01 /usr/local/lib/libopencv_dnn.so.4.5 -> libopencv_dnn.so.4.5.0
-rw-r--r-- 1 root root 45255184 11月 10 06:02 /usr/local/lib/libopencv_dnn.so.4.5.0
lrwxrwxrwx 1 root root 27 12月 19 13:23 /usr/local/lib/libopencv_features2d.so -> libopencv_features2d.so.4.5
lrwxrwxrwx 1 root root 29 12月 19 13:10 /usr/local/lib/libopencv_features2d.so.4.5 -> libopencv_features2d.so.4.5.0
kmtr@ubuntu2010:~/work/opencv_next/build$ ls /usr/local_opencv5/lib/libopen* -al | sort -k 9 | head -10
lrwxrwxrwx 1 root root 24 12月 19 13:27 /usr/local_opencv5/lib/libopencv_calib3d.so -> libopencv_calib3d.so.5.0
lrwxrwxrwx 1 root root 26 12月 19 13:27 /usr/local_opencv5/lib/libopencv_calib3d.so.5.0 -> libopencv_calib3d.so.5.0.0
-rw-r--r-- 1 root root 2739928 12月 19 13:26 /usr/local_opencv5/lib/libopencv_calib3d.so.5.0.0
lrwxrwxrwx 1 root root 21 12月 19 13:27 /usr/local_opencv5/lib/libopencv_core.so -> libopencv_core.so.5.0
lrwxrwxrwx 1 root root 23 12月 19 13:27 /usr/local_opencv5/lib/libopencv_core.so.5.0 -> libopencv_core.so.5.0.0
-rw-r--r-- 1 root root 17690544 12月 19 13:26 /usr/local_opencv5/lib/libopencv_core.so.5.0.0
lrwxrwxrwx 1 root root 20 12月 19 13:27 /usr/local_opencv5/lib/libopencv_dnn.so -> libopencv_dnn.so.5.0
lrwxrwxrwx 1 root root 22 12月 19 13:27 /usr/local_opencv5/lib/libopencv_dnn.so.5.0 -> libopencv_dnn.so.5.0.0
-rw-r--r-- 1 root root 5969384 12月 19 13:26 /usr/local_opencv5/lib/libopencv_dnn.so.5.0.0
lrwxrwxrwx 1 root root 27 12月 19 13:27 /usr/local_opencv5/lib/libopencv_features2d.so -> libopencv_features2d.so.5.0
pkg-configの指定先もオッケー
kmtr@ubuntu2010:~/work/opencv_next/build$ pkg-config opencv4 --cflags --libs
-I/usr/local/include/opencv4 -L/usr/local/lib -lopencv_gapi -lopencv_highgui -lopencv_ml -lopencv_objdetect -lopencv_photo -lopencv_stitching -lopencv_video -lopencv_calib3d -lopencv_features2d -lopencv_flann -lopencv_videoio -lopencv_imgcodecs -lopencv_imgproc -lopencv_core
kmtr@ubuntu2010:~/work/opencv_next/build$ pkg-config opencv5 --cflags --libs
-I/usr/local_opencv5/include/opencv5 -L/usr/local_opencv5/lib -lopencv_gapi -lopencv_highgui -lopencv_ml -lopencv_objdetect -lopencv_photo -lopencv_stitching -lopencv_video -lopencv_calib3d -lopencv_features2d -lopencv_dnn -lopencv_flann -lopencv_videoio -lopencv_imgcodecs -lopencv_imgproc -lopencv_core
shared libraryのサーチパスも追加すればオッケー
kmtr@ubuntu2010:~/work/stb$ export LD_LIBRARY_PATH=$LD_LIBRARY_PATH:/usr/local_opencv5/lib
kmtr@ubuntu2010:~/work/stb$ ldd ./a_next.out
linux-vdso.so.1 (0x00007ffc5a7c4000)
libopencv_imgcodecs.so.5.0 => /usr/local_opencv5/lib/libopencv_imgcodecs.so.5.0 (0x00007f44cb269000)
libopencv_imgproc.so.5.0 => /usr/local_opencv5/lib/libopencv_imgproc.so.5.0 (0x00007f44c94fd000)
libopencv_core.so.5.0 => /usr/local_opencv5/lib/libopencv_core.so.5.0 (0x00007f44c8566000)
libstdc++.so.6 => /lib/x86_64-linux-gnu/libstdc++.so.6 (0x00007f44c8358000)
libgcc_s.so.1 => /lib/x86_64-linux-gnu/libgcc_s.so.1 (0x00007f44c833d000)
libc.so.6 => /lib/x86_64-linux-gnu/libc.so.6 (0x00007f44c8153000)
libpthread.so.0 => /lib/x86_64-linux-gnu/libpthread.so.0 (0x00007f44c812f000)
libjpeg.so.8 => /lib/x86_64-linux-gnu/libjpeg.so.8 (0x00007f44c80aa000)
libwebp.so.6 => /lib/x86_64-linux-gnu/libwebp.so.6 (0x00007f44c7e41000)
libpng16.so.16 => /lib/x86_64-linux-gnu/libpng16.so.16 (0x00007f44c7e08000)
libtiff.so.5 => /lib/x86_64-linux-gnu/libtiff.so.5 (0x00007f44c7d87000)
libopenjp2.so.7 => /lib/x86_64-linux-gnu/libopenjp2.so.7 (0x00007f44c7d31000)
libm.so.6 => /lib/x86_64-linux-gnu/libm.so.6 (0x00007f44c7be0000)
libz.so.1 => /lib/x86_64-linux-gnu/libz.so.1 (0x00007f44c7bc3000)
/lib64/ld-linux-x86-64.so.2 (0x00007f44cb43a000)
libdl.so.2 => /lib/x86_64-linux-gnu/libdl.so.2 (0x00007f44c7bbd000)
liblapack.so.3 => /lib/x86_64-linux-gnu/liblapack.so.3 (0x00007f44c751a000)
libblas.so.3 => /lib/x86_64-linux-gnu/libblas.so.3 (0x00007f44c74ad000)
libzstd.so.1 => /lib/x86_64-linux-gnu/libzstd.so.1 (0x00007f44c73db000)
liblzma.so.5 => /lib/x86_64-linux-gnu/liblzma.so.5 (0x00007f44c73b2000)
libjbig.so.0 => /lib/x86_64-linux-gnu/libjbig.so.0 (0x00007f44c71a4000)
libgfortran.so.5 => /lib/x86_64-linux-gnu/libgfortran.so.5 (0x00007f44c6edc000)
libquadmath.so.0 => /lib/x86_64-linux-gnu/libquadmath.so.0 (0x00007f44c6e92000)
ちゃんと使うべきライブラリが指定されている。
OpenCV 4
kmtr@ubuntu2010:~/work/stb$ strace ./a_45.out 2>&1 | grep openat | grep "opencv" | grep -v ENOENT
openat(AT_FDCWD, "/usr/local/lib/libopencv_imgcodecs.so.4.5", O_RDONLY|O_CLOEXEC) = 3
openat(AT_FDCWD, "/usr/local/lib/libopencv_imgproc.so.4.5", O_RDONLY|O_CLOEXEC) = 3
openat(AT_FDCWD, "/usr/local/lib/libopencv_core.so.4.5", O_RDONLY|O_CLOEXEC) = 3
OpenCV 5
kmtr@ubuntu2010:~/work/stb$ strace ./a_next.out 2>&1 | grep openat | grep "opencv5" | grep -v ENOENT
openat(AT_FDCWD, "/usr/local_opencv5/lib/libopencv_imgcodecs.so.5.0", O_RDONLY|O_CLOEXEC) = 3
openat(AT_FDCWD, "/usr/local_opencv5/lib/libopencv_imgproc.so.5.0", O_RDONLY|O_CLOEXEC) = 3
openat(AT_FDCWD, "/usr/local_opencv5/lib/libopencv_core.so.5.0", O_RDONLY|O_CLOEXEC) = 3
まとめ
- OpenCV4 と OpenCV5の共存はめんどくさいです。
-
CMAKE_INSTALL_PREFIXでインストール先をずらす。 -
export PKG_CONFIG_PATH=/usr/local_opencv5/lib/pkgconfigでpkg-configにopencv5.pcの場所を教える。 -
export LD_LIBRARY_PATH=$LD_LIBRARY_PATH:/usr/local_opencv5/libで実行時にshared libraryの場所を教える。
-
ご精読ありがとうございました！！ 以上となります。