How do you compile OpenCV with cmake? - opencv

Question

I'm trying to compile OpenCV so that it has the the sift module.
I downloaded CMake using this tutorial.
I also downloaded and unzipped opencv-4.3.0 and opencv_contrib.
I made an empty folder, opened the terminal, and navigated to it using the following line:
cd ~/opencvMaster/build
Then, while I was in this empty folder in the terminal, I ran the following line:
cmake -DOPENCV_ENABLE_NONFREE:BOOL=ON -DOPENCV_EXTRA_MODULES_PATH= ~/openCVMaster/opencv_contrib-master/modules ~/openCVMaster/opencv-4.3.0
It configured and generated the files. I then input make. Got the following error:
[ 82%] Building CXX object modules/xfeatures2d/CMakeFiles/opencv_xfeatures2d.dir/src/boostdesc.cpp.o
~/opencvMaster/opencv_contrib-e6f32c6a69043456a806a4e802ee3ce7b7059c93/modules/xfeatures2d/src/boostdesc.cpp:654:20: fatal error: boostdesc_bgm.i: No such file or directory
#include "boostdesc_bgm.i"
^~~~~~~~~~~~~~~~~
compilation terminated.
I followed the suggestion found here, and added the following files:
cd ~/openCVMaster/opencv_contrib-4.3.0/modules/xfeatures2d/src
curl wget https://raw.githubusercontent.com/opencv/opencv_3rdparty/34e4206aef44d50e6bbcd0ab06354b52e7466d26/boostdesc_lbgm.i >boostdesc_lbgm.i
curl wget https://raw.githubusercontent.com/opencv/opencv_3rdparty/34e4206aef44d50e6bbcd0ab06354b52e7466d26/boostdesc_binboost_256.i >boostdesc_binboost_256.i
curl wget https://raw.githubusercontent.com/opencv/opencv_3rdparty/34e4206aef44d50e6bbcd0ab06354b52e7466d26/boostdesc_binboost_128.i >boostdesc_binboost_128.i
curl wget https://raw.githubusercontent.com/opencv/opencv_3rdparty/34e4206aef44d50e6bbcd0ab06354b52e7466d26/boostdesc_binboost_064.i >boostdesc_binboost_064.i
curl wget https://raw.githubusercontent.com/opencv/opencv_3rdparty/34e4206aef44d50e6bbcd0ab06354b52e7466d26/boostdesc_bgm_hd.i >boostdesc_bgm_hd.i
curl wget https://raw.githubusercontent.com/opencv/opencv_3rdparty/34e4206aef44d50e6bbcd0ab06354b52e7466d26/boostdesc_bgm_bi.i >boostdesc_bgm_bi.i
curl wget https://raw.githubusercontent.com/opencv/opencv_3rdparty/34e4206aef44d50e6bbcd0ab06354b52e7466d26/boostdesc_bgm.i >boostdesc_bgm.i
curl wget https://raw.githubusercontent.com/opencv/opencv_3rdparty/fccf7cd6a4b12079f73bbfb21745f9babcd4eb1d/vgg_generated_120.i > vgg_generated_120.i
curl wget https://raw.githubusercontent.com/opencv/opencv_3rdparty/fccf7cd6a4b12079f73bbfb21745f9babcd4eb1d/vgg_generated_64.i >vgg_generated_64.i
curl wget https://raw.githubusercontent.com/opencv/opencv_3rdparty/fccf7cd6a4b12079f73bbfb21745f9babcd4eb1d/vgg_generated_48.i >vgg_generated_48.i
curl wget https://raw.githubusercontent.com/opencv/opencv_3rdparty/fccf7cd6a4b12079f73bbfb21745f9babcd4eb1d/vgg_generated_80.i >vgg_generated_80.i
This was a step forward: no more errors relating to vgg or boostdesc. A new error appeared: opencv_contrib-master/modules/xfeatures2d/test/test_features2d.cpp:51:10: fatal error: features2d/test/test_detectors_regression.impl.hpp: No such file or directory
Following the advice of ah-ma here) I downloaded https://github.com/opencv/opencv/tree/master/modules. Once downloaded, I located its subfolder 'features2d' and put it in opencv_contrib-master/modules/xfeatures2d/test/.
Still got an error -
~/openCVMaster/opencv_contrib-master/modules/xfeatures2d/test/features2d/misc/java/src/cpp/features2d_converters.cpp:2:10: fatal error: common.h: No such file or directory
#include "common.h"
I added the following:
cd ~/openCVMaster/opencv_contrib-master/modules/xfeatures2d/test/features2d/misc/java/src/cpp
curl wget https://raw.githubusercontent.com/ray-project/common/master/common.h > common.h
I ran make again, and got the following errors:
~/openCVMaster/opencv_contrib-master/modules/xfeatures2d/test/features2d/misc/java/src/cpp/features2d_converters.cpp: In function ‘void Mat_to_vector_KeyPoint(cv::Mat&, std::vector<cv::KeyPoint>&)’:
~/openCVMaster/opencv_contrib-master/modules/xfeatures2d/test/features2d/misc/java/src/cpp/features2d_converters.cpp:7:38: error: ‘LOGD’ was not declared in this scope
#define CHECK_MAT(cond) if(!(cond)){ LOGD("FAILED: " #cond); return; }
~/openCVMaster/opencv_contrib-master/modules/xfeatures2d/test/features2d/misc/java/src/cpp/features2d_converters.cpp:14:5: note: in expansion of macro ‘CHECK_MAT’
CHECK_MAT(mat.type()==CV_32FC(7) && mat.cols==1);
^~~~~~~~~
~/openCVMaster/opencv_contrib-master/modules/xfeatures2d/test/features2d/misc/java/src/cpp/features2d_converters.cpp: In function ‘void Mat_to_vector_DMatch(cv::Mat&, std::vector<cv::DMatch>&)’:
~/openCVMaster/opencv_contrib-master/modules/xfeatures2d/test/features2d/misc/java/src/cpp/features2d_converters.cpp:7:38: error: ‘LOGD’ was not declared in this scope
#define CHECK_MAT(cond) if(!(cond)){ LOGD("FAILED: " #cond); return; }
Any suggestions welcomed.

Answer 1

# Step 1: Install VS 2017 for cmake
# Step 2: Install CMake
Download and install CMake v3.10.0 from https://cmake.org/download/.
During installation select “Add CMake to system PATH”
# step 3: install Anaconda
# step 4: Download and extract opencv-3.3.1 and opencv_contrib-3.3.1
Go to https://github.com/opencv/opencv/releases and download opencv-3.3.1 source code zip
Go to https://github.com/opencv/opencv_contrib/releases and download opencv_contrib-3.3.1 source code zip
Extract both zip files. Although you can keep opencv and opencv_contrib folders anywhere, I suggest that you should keep both in the same directory. I have placed these two folders in “My Documents” directory.
NOTE : From hereon we will refer the path to opencv-3.3.1 folder as OPENCV_PATH. For example, in my case OPENCV_PATH is C:/Users/Vaibhaw Chandel/Documents/opencv-3.3.1
Depending upon where you have kept opencv-3.3.1 folder, this path would be different.
Step 5: Generate Visual Studio project using CMake
Run Cmake, in box “Where is the source code” write value of OPENCV_PATH (which is path to opencv-3.3.1 folder) and path to build directory. We will choose build directory as OPENCV_PATH/build
Now click configure.
You will be asked for permission to create the build folder. Click Yes
When prompted to select a compiler, select Visual Studio 14 2015 Win64.
Click finish and in the next window keep the default parameters checked.
Click finish. Now CMake will look in the system directories and generate the makefiles.
Step 5.1: Additional changes to CMake config
We will make few changes in the default configuration generated by CMake. Click on the images to see a larger version.
Check “INSTALL_C_EXAMPLES” and “INSTALL_PYTHON_EXAMPLES”
In flag “OPENCV_EXTRA_MODULES_PATH”, give path of modules directory within opencv_contrib-3.3.1. In our case we have kept opencv_contrib-3.3.1 in Documents folder so path is “C:/Users/Vaibhaw Chandel/Documents/opencv_contrib-3.3.1/modules”
Now click configure to apply these changes.
On Windows 10, opencv_saliency module fails to build. So we will disable it. Uncheck BUILD_opencv_saliency
Now click on configure again to include this change.
Step 5.2 : Add Python paths for both Python2 and Python3 (optional)
This section is only for people who want to generate OpenCV binary for both Python2 and Python 3. If you are going to use just one Python either 2 or 3, you should skip this section.
CMake was unable to find paths for my Python3 files.
So I manually added paths for Python3
Now click configure again. After configuring is done, search opencv_python in search bar, both BUILD_opencv_python2 and BUILD_opencv_python3 will be automatically checked. Now we are sure that OpenCV binaries for both Python2 and Python 3 will be generated after compilation.
Step 5.3 : Generate build files
If CMake is able to configure without any errors it should say “Configuring done”.
Click generate.
Note: Whenever you make any changes(check/uncheck boxes or change path) to configuration generated by CMake, always click configure and generate.
Step 6: Compile OpenCV
Step 6.1:Compile opencv in Release mode
Open Windows Command Prompt (cmd).
Go to OPENCV_PATH/build directory and run this command
1
cmake.exe --build . --config Release --target INSTALL
Step 6.2 : Compile opencv in Debug mode
Open CMake GUI again as mentioned in Step 5.
Search “python” in search box
Uncheck INSTALL_PYTHON_EXAMPLES, BUILD_opencv_python3 and BUILD_opencv_python2
Click configure
Click generate
Now in windows command prompt
Go to OPENCV_PATH/build directory and run this command
1
cmake.exe --build . --config Debug --target INSTALL
Now that we have compiled OpenCV we will find out how to test a OpenCV project using CMake.
Step 7: Update System Environment Variables
Step 7.1 : Update environment variable – PATH
Step 7.2 : Update user environment variable – OPENCV_DIR

Answer 2

Download opencv-4.3.0.zip and opencv_contrib-4.3.0.zip. Unzip them.
Open opencv_contrib-4.3.0\modules. Copy the folder that says xfeatures2d. Open opencv-4.3.0\modules, and paste the folder just copied (xfeatures2d)
Make an empty folder, and call it 'Build45.'
Open cmake-gui.
In the box that says, 'Where to build the binaries' put the file path representing your empty folder (Build45)
In the box that says, 'Where is the source code' put the file path representing opencv-4.3.0.
Click configure. Choices will appear.
Input 'free' into the search box and check the box that says OPENCV_ENABLE_NONFREE.
Input xfeatures2d and check the box that says 'Build_opencv_xfeatures2d`
Click configure again. (Doublecheck you've done this right: there is a second box in cmake gui that gives build details. You should see Non-free algorithms: YES.
Click Generate.
Check that the build45 folder is now filled with stuff.
Open your terminal and navigate to the build45 folder (cd ~/opencv-master/build45)
Type cmake .
Type make
NOTE:* It will take a couple hours to compile. Make yourself a cup of tea*.
Type sudo make install
Check that it worked: in your terminal, type python3
Type import cv2
Type sift = cv2.xfeatures2d.SIFT_create()
You should get no errors. If you do get errors, the following troubleshooting tools may be helpful:
import cv2
print cv2.getBuildInformation()
import cv2
funcs = dir(cv2)
for f in funcs:
... print(f)
Also, if you are worried about infringing patents, check here for discussion: https://www.reddit.com/r/computervision/comments/ba1l8g/according_to_this_the_patent_on_sift_was_due_to/