OpenCV released OpenCV-3.4.4 and OpenCV-4.0.0 on 20th November. There have been a lot of bug fixes and other changes in these versions. The release highlights are as follows:
Visual Studio 2019 allows C developers to target both Windows and Linux (including the Windows Subsystem for Linux) from the comfort of a single IDE. Visual Studio 2019 version 16.7 Preview 3 introduces two features specific to Linux development: improved build incrementality for MSBuild-based Linux projects, and support for a wider range of. Feb 25, 2020 How to add “graphics.h” C/C library to gcc compiler in Linux C C Server Side Programming Programming In this tutorial, we will be discussing a program to understand how to add “graphics.h” C/C library to gcc compiler in Linux.
- OpenCV is now C++11 library and requires C++11-compliant compiler. Minimum required CMake version has been raised to 3.5.1.
- A lot of C API from OpenCV 1.x has been removed.
- Persistence (storing and loading structured data to/from XML, YAML or JSON) in the core module has been completely reimplemented in C++ and lost the C API as well.
- New module G-API has been added, it acts as an engine for very efficient graph-based image procesing pipelines.
- dnn module now includes experimental Vulkan backend and supports networks in ONNX format.
- The popular Kinect Fusion algorithm has been implemented and optimized for CPU and GPU (OpenCL)
QR code detector and decoder have been added to the objdetect module. - Very efficient and yet high-quality DIS dense optical flow algorithm has been moved from opencv_contrib to the video module.
There are several alternatives for compiling C on Linux. Let's look at 2 of them − GCC. Almost all Linux distros come with GCC installed. Check whether GCC is installed on your system by entering the following command from the command line −.
In this post, we will provide a bash script for installing OpenCV-3.4.4 (C++ and Python 3.5) on Ubuntu 16.04. We will also briefly study the script to understand what’s going in it. Note that this script will install OpenCV in a local directory and not on the entire system.
Looking for installation script for OpenCV 3.4.4 on Ubuntu 18.04? Have a look at this blog.
Step 0: Select OpenCV version to install
We are also going to clean
build
directories and create installation
directory.Finally, we will be storing the current working directory in
cwd
variable. We are also going to refer to this directory as OpenCV_Home_Dir throughout this blog.Step 1: Update Packages
If you are still not able to install OpenCV on your system, but want to get started with it, we suggest using our docker images with pre-installed OpenCV, Dlib, miniconda and jupyter notebooks along with other dependencies as described in this blog.
Step 2: Install OS Libraries
Looking for installation script for OpenCV 4 on Ubuntu 16.04? Have a look at this blog.
Step 3: Install Python Libraries
If you are solely a Python user, it is easier to use pip install opencv-contrib-python3.4.4.19.
Download Installation Script
To easily follow along this tutorial, please download installation script by clicking on the button below. It’s FREE!
To easily follow along this tutorial, please download installation script by clicking on the button below. It’s FREE!
Step 4: Download opencv and opencv_contrib
Step 5: Compile and install OpenCV with contrib modules
Install Dev C Linux Terminal Tree Real Estate Jasper Georgia
First we navigate to the build directory.
Next, we start the compilation and installation process.
For system wide installation of OpenCV, change CMAKE_INSTALL_PREFIX to CMAKE_INSTALL_PREFIX=/usr/local .
There are two ways to use OpenCV in C++, the preferred way is to use CMake, the other one being command line compilation using g++. We will have a look at both ways.
Using CMakeLists.txt
The basic structure of your CMakeLists.txt will stay the same. Only difference being, that you will have to set OpenCV_DIR as shown below.
The basic structure of your CMakeLists.txt will stay the same. Only difference being, that you will have to set OpenCV_DIR as shown below.
Linux Terminal Commands
Make sure that you replace OpenCV_Home_Dir with correct path. For example, in my case:
Once you have made your CMakeLists.txt, follow the steps given below.
This will generate your executable file in build directory.
Using g++
To compile a sample file (let’s say
my_sample_file.cpp
), use the following command.To use the OpenCV version installed using Python script, first we activate the Python Virtual Environment.
For OpenCV-3.4.4 : Python 3
Once you have activated the virtual environment, you can enter Python shell and test OpenCV version.
Hope this script proves to be useful for you :). Stay tuned for more interesting stuff. In case of any queries, feel free to comment below and we will get back to you as soon as possible.
Subscribe & Download Code
If you liked this article and would like to download code (C++ and Python) and example images used in this post, please subscribe to our newsletter. You will also receive a free Computer Vision Resource Guide. In our newsletter, we share OpenCV tutorials and examples written in C++/Python, and Computer Vision and Machine Learning algorithms and news.