I had already installed opencv 2.4.2 on my ubuntu 12.04 lts system. But now I have such a situation that I should install opencv 2.2.0 also. I would like to keep opencv 2.4.2. Is it possible?
Reason: I should use econ ECAM32 usb web cam to take images using opencv program but opencv 2.4.2 is not supporting this cam. But opencv 2.2 is supporting this cam.
I would like to hear how we can install opencv 2.2 on system in any other directory, I would prefer on folder in home directory,so that installation should not damage opencv 2.4.2.
I don't see why not. ubuntu 12.04 has opencv 2.3 in it's repository therefore I'm assuming you have installed from the source. when you compile the source you should check ./configure --help first which would probably give you an option for installation directory. It usually looks like:
./configure --prefix=$HOME/opencv2.2
let me know how you proceed..
Related
I have OpenCV 3.4 installed in Ubuntu 18. I also have installed ROS Melodic according to the website instructions. However, I keep on getting an error that libopencv_core.so.3.2 is required.
I already set my CMakeLists files to point to OpenCV 3.4.
However, I found out that in the file:
/ros/melodic/share/cv_bridge/cmake/cv_bridgeConfig.cmake
there is the following line hardcoded in opencv3.2:
set(libraries "cv_bridge;/usr/lib/x86_64-linux-gnu/libopencv_core.so.3.2.0;/usr/lib/x86_64-linux-gnu/libopencv_imgproc.so.3.2.0;/usr/lib/x86_64-linux-gnu/libopencv_imgcodecs.so.3.2.0").
I tried to change it to 3.4 but I can not rebuild it.
The error I am getting is:
/opt/ros/melodic/lib/image_view/image_view: error while loading shared libraries: libopencv_core.so.3.2: cannot open shared object file: No such file or directory
Why is OpenCV 3.2 hardcoded in cv_bridge and how can I rebuild it with OpenCV 3.4?
Update:
I eventually installed OpenCV 3.2 and it worked properly.
Because opencv development speed is much faster than ROS individual module. And a lot of ROS modules went depreciated after someone left the job.
But that's by no means the end of the day( maybe end of the day for noobs). You can build it directly with any version of opencv core function(besides imshow kind of function) others should perform just fine.
The easiest way is to do is: in the console before executing catkin_make try to execute the following
export CMAKE_PREFIX_PATH=/usr/local:$CMAKE_PREFIX_PATH
export LD_LIBRARY_PATH=/usr/local/lib:$LD_LIBRARY_PATH
This should give preference to your custom OpenCV installation when doing the find_package(OpenCV 3.X.0 REQUIRED). Then compile and use the function of that version.
Well if you do have to use 3.4 then I think you have to build ros version of opencv and image transport and cvbridge to the 3.4 if that's what you are targeting.
You can find the link here https://github.com/ros-gbp/opencv3-release The highest they provide seems to be 3.3
I installed Darknet with CUDA support. I ran
./darknet detector test cfg/coco.data cfg/yolov3.cfg yolov3.weights data/dog.jpg
I want it to run with opencv support. I had already installed opencv.
I compiled darknet with remake/make after making OPENCV=1 in Makefile, but still it is not detecting the installed opencv.
How can I make it to detect the already installed opencv?
I have installed opencv with this command pip install opencv-python --user before installing darknet.
You need to install the c++ libraries not just the python wrapper. You can do it from the sources: https://docs.opencv.org/trunk/d7/d9f/tutorial_linux_install.html.
In order to compile Darknet you will need OpenCV works with C/C++ code, not python. To check whether you have installed OpenCV correctly and can be used in C program, run this command :
pkg-config --modversion opencv
If it doesn't show anything or shows wrong version, try to reinstall OpenCV OR it is possible that your machine doesn't locate opencv version correctly.
So add command to your ~/.bashrc for example :
vim ~/.bashrc
export PKG_CONFIG_PATH=/home/user/installation/OpenCV-3.4.0/lib/pkgconfig
source ~/.bashrc
Notes : Change the path according to your opencv installation directory that contains opencv.pc
If you're following this repo https://github.com/AlexeyAB/darknet for Windows/Linux you need to download openCV (both OpenCV 2.x.x and OpenCV <= 3.4.0 (3.4.1 and higher isn't supported)) and put in this path for
Windows: ( C:\opencv_3.0\opencv\build\include & C:\opencv_3.0\opencv\build\x64\vc14\lib)
More instructions in the repo. If you're on Windows/Linux and still trying to figure things out you may check a video I made on that topic https://youtu.be/-HtiYHpqnBs
I want to install OpenCV on arm board installed ubuntu 16.04 arm OS.
Most of the docs. install OpenCV using a cross-compiler.
I've never used cross-compiler, I have a few question about it
Why do I need use cross-compiler to install OpenCV?
If I install using a cross-compiler, then always host-computer need when any of source code using OpenCV running?
Having Gstreamer 1.22 successfully installed I'm not able to configure the project to build OpenCV. CMake isn't able to find GStreamer on my machine. Any ideas how two address this issue?
Just found the solution:
Cmake is using FindGstreamerWindows.cmake to find GStreamer on Windows, which is using internal an environment variable called "GSTREAMER_DIR" pointing to ..\gstreamer\1.0\x86_64.
Please make sure GSTREAMER_DIR exists on your machine.
I recently compile Opencv 4.2 with GStreamer on Windows. I use settings for GStreamer as on the following pictures. Make sure you point to correct .lib and include directories. all_Library is gstapp-1.0.lib etc, when configuraing CMAKE to compile OpenCV.
I use Opencv 4.2, CMake 3.17.0 release candidate and Gstreamer 1.16.2 MSVC 64-bit (VS 2019) developer and runtime installer. The whole process is described here install OpenCV on windows GStreamer tutorial
The important part is to set up environmental variables to find Gstreamer Runtime. Into system variable path: add
xxx\1.0\x86_64\bin
xxx\1.0\x86_64\lib
xxx\1.0\x86_64\lib\gstreamer-1.0
Gstreamer pipe from c++ opencv program to the web.
I have a problem trying to get a webcam in OpenCV 2.3 to work with Cygwin. I have a Windows 7 64-bit system and I use Notepad++ and cygwin compilers to do my C++ programming. I have seen other posts with similar problems:
Getting Webcam to work in OpenCV
Can't access webcam with OpenCV
I first tried installing OpenCV via the Cygwin Ports. This is rather easy to install, but alas I run into the webcam problem (always returns false when trying to find a device). I have also attempted to build OpenCV and install manually using the command line flavor of CMake. I tried adding the HAVE_VIDEOINPUT and HAVE_DSHOW flags, but no dice. All my programs compile nicely and I have all the functionality of OpenCV aside for this webcam thing.
Has anyone successfully built OpenCV 2.3 on Cygwin with webcam working?
It is unlikely that cygwin build of OpenCV will be able to access a webcam. At least it is not possible without hacking OpenCV cmake scripts. Under cygwin OpenCV build always follows the UNIX branch and videoinput/directshow is excluded from build.