feat: 切换后端至PaddleOCR-NCNN，切换工程为CMake

1.项目后端整体迁移至PaddleOCR-NCNN算法，已通过基本的兼容性测试
2.工程改为使用CMake组织，后续为了更好地兼容第三方库，不再提供QMake工程
3.重整权利声明文件，重整代码工程，确保最小化侵权风险

Log: 切换后端至PaddleOCR-NCNN，切换工程为CMake
Change-Id: I4d5d2c5d37505a4a24b389b1a4c5d12f17bfa38c

3rdparty/opencv-4.5.4/doc/py_tutorials/py_setup/py_intro/py_intro.markdown

@@ -0,0 +1,86 @@
+Introduction to OpenCV-Python Tutorials {#tutorial_py_intro}
+=======================================
+
+OpenCV
+------
+
+OpenCV was started at Intel in 1999 by **Gary Bradsky**, and the first release came out in 2000.
+**Vadim Pisarevsky** joined Gary Bradsky to manage Intel's Russian software OpenCV team. In 2005,
+OpenCV was used on Stanley, the vehicle that won the 2005 DARPA Grand Challenge. Later, its active
+development continued under the support of Willow Garage with Gary Bradsky and Vadim Pisarevsky
+leading the project. OpenCV now supports a multitude of algorithms related to Computer Vision and
+Machine Learning and is expanding day by day.
+
+OpenCV supports a wide variety of programming languages such as C++, Python, Java, etc., and is
+available on different platforms including Windows, Linux, OS X, Android, and iOS. Interfaces for
+high-speed GPU operations based on CUDA and OpenCL are also under active development.
+
+OpenCV-Python is the Python API for OpenCV, combining the best qualities of the OpenCV C++ API and
+the Python language.
+
+OpenCV-Python
+-------------
+
+OpenCV-Python is a library of Python bindings designed to solve computer vision problems.
+
+Python is a general purpose programming language started by **Guido van Rossum** that became very
+popular very quickly, mainly because of its simplicity and code readability. It enables the
+programmer to express ideas in fewer lines of code without reducing readability.
+
+Compared to languages like C/C++, Python is slower. That said, Python can be easily extended with
+C/C++, which allows us to write computationally intensive code in C/C++ and create Python wrappers
+that can be used as Python modules. This gives us two advantages: first, the code is as fast as the
+original C/C++ code (since it is the actual C++ code working in background) and second, it easier to
+code in Python than C/C++. OpenCV-Python is a Python wrapper for the original OpenCV C++
+implementation.
+
+OpenCV-Python makes use of **Numpy**, which is a highly optimized library for numerical operations
+with a MATLAB-style syntax. All the OpenCV array structures are converted to and from Numpy arrays.
+This also makes it easier to integrate with other libraries that use Numpy such as SciPy and
+Matplotlib.
+
+OpenCV-Python Tutorials
+-----------------------
+
+OpenCV introduces a new set of tutorials which will guide you through various functions available in
+OpenCV-Python. **This guide is mainly focused on OpenCV 3.x version** (although most of the
+tutorials will also work with OpenCV 2.x).
+
+Prior knowledge of Python and Numpy is recommended as they won't be covered in this guide.
+**Proficiency with Numpy is a must in order to write optimized code using OpenCV-Python.**
+
+This tutorial was originally started by *Abid Rahman K.* as part of the Google Summer of Code 2013
+program under the guidance of *Alexander Mordvintsev*.
+
+OpenCV Needs You !!!
+--------------------
+
+Since OpenCV is an open source initiative, all are welcome to make contributions to the library,
+documentation, and tutorials. If you find any mistake in this tutorial (from a small spelling
+mistake to an egregious error in code or concept), feel free to correct it by cloning OpenCV in
+[GitHub](https://github.com/opencv/opencv) and submitting a pull request. OpenCV developers will
+check your pull request, give you important feedback and (once it passes the approval of the
+reviewer) it will be merged into OpenCV. You will then become an open source contributor :-)
+
+As new modules are added to OpenCV-Python, this tutorial will have to be expanded. If you are
+familiar with a particular algorithm and can write up a tutorial including basic theory of the
+algorithm and code showing example usage, please do so.
+
+Remember, we **together** can make this project a great success !!!
+
+Contributors
+------------
+
+Below is the list of contributors who submitted tutorials to OpenCV-Python.
+
+-#  Alexander Mordvintsev (GSoC-2013 mentor)
+2.  Abid Rahman K. (GSoC-2013 intern)
+
+Additional Resources
+--------------------
+
+-#  A Quick guide to Python - [A Byte of Python](http://swaroopch.com/notes/python/)
+2.  [NumPy Quickstart tutorial](https://numpy.org/devdocs/user/quickstart.html)
+3.  [NumPy Reference](https://numpy.org/devdocs/reference/index.html#reference)
+4.  [OpenCV Documentation](http://docs.opencv.org/)
+5.  [OpenCV Forum](https://forum.opencv.org/)

3rdparty/opencv-4.5.4/doc/py_tutorials/py_setup/py_setup_in_fedora/py_setup_in_fedora.markdown

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+Install OpenCV-Python in Fedora {#tutorial_py_setup_in_fedora}
+===============================
+
+Goals
+-----
+
+In this tutorial
+    -   We will learn to setup OpenCV-Python in your Fedora system. Below steps are tested for
+        Fedora 18 (64-bit) and Fedora 19 (32-bit).
+
+Introduction
+------------
+
+OpenCV-Python can be installed in Fedora in two ways, 1) Install from pre-built binaries available
+in fedora repositories, 2) Compile from the source. In this section, we will see both.
+
+Another important thing is the additional libraries required. OpenCV-Python requires only **Numpy**
+(in addition to other dependencies, which we will see later). But in this tutorials, we also use
+**Matplotlib** for some easy and nice plotting purposes (which I feel much better compared to
+OpenCV). Matplotlib is optional, but highly recommended. Similarly we will also see **IPython**, an
+Interactive Python Terminal, which is also highly recommended.
+
+Installing OpenCV-Python from Pre-built Binaries
+------------------------------------------------
+
+Install all packages with following command in terminal as root.
+@code{.sh}
+$ yum install numpy opencv*
+@endcode
+Open Python IDLE (or IPython) and type following codes in Python terminal.
+@code{.py}
+>>> import cv2 as cv
+>>> print( cv.__version__ )
+@endcode
+If the results are printed out without any errors, congratulations !!! You have installed
+OpenCV-Python successfully.
+
+It is quite easy. But there is a problem with this. Yum repositories may not contain the latest
+version of OpenCV always. For example, at the time of writing this tutorial, yum repository contains
+2.4.5 while latest OpenCV version is 2.4.6. With respect to Python API, latest version will always
+contain much better support. Also, there may be chance of problems with camera support, video
+playback etc depending upon the drivers, ffmpeg, gstreamer packages present etc.
+
+So my personal preference is next method, i.e. compiling from source. Also at some point in time,
+if you want to contribute to OpenCV, you will need this.
+
+Installing OpenCV from source
+-----------------------------
+
+Compiling from source may seem a little complicated at first, but once you succeeded in it, there is
+nothing complicated.
+
+First we will install some dependencies. Some are compulsory, some are optional. Optional
+dependencies, you can leave if you don't want.
+
+### Compulsory Dependencies
+
+We need **CMake** to configure the installation, **GCC** for compilation, **Python-devel** and
+**Numpy** for creating Python extensions etc.
+@code{.sh}
+yum install cmake
+yum install python-devel numpy
+yum install gcc gcc-c++
+@endcode
+Next we need **GTK** support for GUI features, Camera support (libdc1394, v4l), Media Support
+(ffmpeg, gstreamer) etc.
+@code{.sh}
+yum install gtk2-devel
+yum install libdc1394-devel
+yum install ffmpeg-devel
+yum install gstreamer-plugins-base-devel
+@endcode
+### Optional Dependencies
+
+Above dependencies are sufficient to install OpenCV in your fedora machine. But depending upon your
+requirements, you may need some extra dependencies. A list of such optional dependencies are given
+below. You can either leave it or install it, your call :)
+
+OpenCV comes with supporting files for image formats like PNG, JPEG, JPEG2000, TIFF, WebP etc. But
+it may be a little old. If you want to get latest libraries, you can install development files for
+these formats.
+@code{.sh}
+yum install libpng-devel
+yum install libjpeg-turbo-devel
+yum install jasper-devel
+yum install openexr-devel
+yum install libtiff-devel
+yum install libwebp-devel
+@endcode
+Several OpenCV functions are parallelized with **Intel's Threading Building Blocks** (TBB). But if
+you want to enable it, you need to install TBB first. ( Also while configuring installation with
+CMake, don't forget to pass -D WITH_TBB=ON. More details below.)
+@code{.sh}
+yum install tbb-devel
+@endcode
+OpenCV uses another library **Eigen** for optimized mathematical operations. So if you have Eigen
+installed in your system, you can exploit it. ( Also while configuring installation with CMake,
+don't forget to pass -D WITH_EIGEN=ON. More details below.)
+@code{.sh}
+yum install eigen3-devel
+@endcode
+If you want to build **documentation** ( *Yes, you can create offline version of OpenCV's complete
+official documentation in your system in HTML with full search facility so that you need not access
+internet always if any question, and it is quite FAST!!!* ), you need to install **Doxygen** (a
+documentation generation tool).
+@code{.sh}
+yum install doxygen
+@endcode
+### Downloading OpenCV
+
+Next we have to download OpenCV. You can download the latest release of OpenCV from [sourceforge
+site](http://sourceforge.net/projects/opencvlibrary/). Then extract the folder.
+
+Or you can download latest source from OpenCV's github repo. (If you want to contribute to OpenCV,
+choose this. It always keeps your OpenCV up-to-date). For that, you need to install **Git** first.
+@code{.sh}
+yum install git
+git clone https://github.com/opencv/opencv.git
+@endcode
+It will create a folder OpenCV in home directory (or the directory you specify). The cloning may
+take some time depending upon your internet connection.
+
+Now open a terminal window and navigate to the downloaded OpenCV folder. Create a new build folder
+and navigate to it.
+@code{.sh}
+mkdir build
+cd build
+@endcode
+### Configuring and Installing
+
+Now we have installed all the required dependencies, let's install OpenCV. Installation has to be
+configured with CMake. It specifies which modules are to be installed, installation path, which
+additional libraries to be used, whether documentation and examples to be compiled etc. Below
+command is normally used for configuration (executed from build folder).
+@code{.sh}
+cmake -D CMAKE_BUILD_TYPE=RELEASE -D CMAKE_INSTALL_PREFIX=/usr/local ..
+@endcode
+It specifies that build type is "Release Mode" and installation path is /usr/local. Observe the -D
+before each option and .. at the end. In short, this is the format:
+@code{.sh}
+cmake [-D <flag>] [-D <flag>] ..
+@endcode
+You can specify as many flags you want, but each flag should be preceded by -D.
+
+So in this tutorial, we are installing OpenCV with TBB and Eigen support. We also build the
+documentation, but we exclude Performance tests and building samples. We also disable GPU related
+modules (since we use OpenCV-Python, we don't need GPU related modules. It saves us some time).
+
+*(All the below commands can be done in a single cmake statement, but it is split here for better
+understanding.)*
+
+-   Enable TBB and Eigen support:
+    @code{.sh}
+    cmake -D WITH_TBB=ON -D WITH_EIGEN=ON ..
+    @endcode
+-   Enable documentation and disable tests and samples
+    @code{.sh}
+    cmake -D BUILD_DOCS=ON -D BUILD_TESTS=OFF -D BUILD_PERF_TESTS=OFF -D BUILD_EXAMPLES=OFF ..
+    @endcode
+-   Disable all GPU related modules.
+    @code{.sh}
+    cmake -D WITH_OPENCL=OFF -D BUILD_opencv_gpu=OFF -D BUILD_opencv_gpuarithm=OFF -D BUILD_opencv_gpubgsegm=OFF -D BUILD_opencv_gpucodec=OFF -D BUILD_opencv_gpufeatures2d=OFF -D BUILD_opencv_gpufilters=OFF -D BUILD_opencv_gpuimgproc=OFF -D BUILD_opencv_gpulegacy=OFF -D BUILD_opencv_gpuoptflow=OFF -D BUILD_opencv_gpustereo=OFF -D BUILD_opencv_gpuwarping=OFF ..
+    @endcode
+-   Set installation path and build type
+    @code{.sh}
+    cmake -D CMAKE_BUILD_TYPE=RELEASE -D CMAKE_INSTALL_PREFIX=/usr/local ..
+    @endcode
+Each time you enter cmake statement, it prints out the resulting configuration setup. In the final
+setup you got, make sure that following fields are filled (below is the some important parts of
+configuration I got). These fields should be filled appropriately in your system also. Otherwise
+some problem has happened. So check if you have correctly performed above steps.
+@code{.sh}
+...
+--   GUI:
+--     GTK+ 2.x:                    YES (ver 2.24.19)
+--     GThread :                    YES (ver 2.36.3)
+
+--   Video I/O:
+--     DC1394 2.x:                  YES (ver 2.2.0)
+--     FFMPEG:                      YES
+--       codec:                     YES (ver 54.92.100)
+--       format:                    YES (ver 54.63.104)
+--       util:                      YES (ver 52.18.100)
+--       swscale:                   YES (ver 2.2.100)
+--       gentoo-style:              YES
+--     GStreamer:
+--       base:                      YES (ver 0.10.36)
+--       video:                     YES (ver 0.10.36)
+--       app:                       YES (ver 0.10.36)
+--       riff:                      YES (ver 0.10.36)
+--       pbutils:                   YES (ver 0.10.36)
+
+--     V4L/V4L2:                    Using libv4l (ver 1.0.0)
+
+--   Other third-party libraries:
+--     Use Eigen:                   YES (ver 3.1.4)
+--     Use TBB:                     YES (ver 4.0 interface 6004)
+
+--   Python:
+--     Interpreter:                 /usr/bin/python2 (ver 2.7.5)
+--     Libraries:                   /lib/libpython2.7.so (ver 2.7.5)
+--     numpy:                       /usr/lib/python2.7/site-packages/numpy/core/include (ver 1.7.1)
+--     packages path:               lib/python2.7/site-packages
+
+...
+@endcode
+Many other flags and settings are there. It is left for you for further exploration.
+
+Now you build the files using make command and install it using make install command. make install
+should be executed as root.
+@code{.sh}
+make
+su
+make install
+@endcode
+Installation is over. All files are installed in /usr/local/ folder. But to use it, your Python
+should be able to find OpenCV module. You have two options for that.
+
+-#  **Move the module to any folder in Python Path** : Python path can be found out by entering
+    `import sys; print(sys.path)` in Python terminal. It will print out many locations. Move
+    /usr/local/lib/python2.7/site-packages/cv2.so to any of this folder. For example,
+    @code{.sh}
+    su mv /usr/local/lib/python2.7/site-packages/cv2.so /usr/lib/python2.7/site-packages
+    @endcode
+But you will have to do this every time you install OpenCV.
+
+-#  **Add /usr/local/lib/python2.7/site-packages to the PYTHON_PATH**: It is to be done only once.
+    Just open \~/.bashrc and add following line to it, then log out and come back.
+    @code{.sh}
+    export PYTHONPATH=$PYTHONPATH:/usr/local/lib/python2.7/site-packages
+    @endcode
+Thus OpenCV installation is finished. Open a terminal and try 'import cv2 as cv'.
+
+To build the documentation, just enter following commands:
+@code{.sh}
+make doxygen
+@endcode
+Then open opencv/build/doc/doxygen/html/index.html and bookmark it in the browser.
+
+Additional Resources
+--------------------
+
+Exercises
+---------
+
+-#  Compile OpenCV from source in your Fedora machine.

3rdparty/opencv-4.5.4/doc/py_tutorials/py_setup/py_setup_in_ubuntu/py_setup_in_ubuntu.markdown

@@ -0,0 +1,184 @@
+Install OpenCV-Python in Ubuntu {#tutorial_py_setup_in_ubuntu}
+===============================
+
+Goals
+-----
+
+In this tutorial We will learn to setup OpenCV-Python in Ubuntu System.
+Below steps are tested for Ubuntu 16.04 and 18.04 (both 64-bit).
+
+OpenCV-Python can be installed in Ubuntu in two ways:
+- Install from pre-built binaries available in Ubuntu repositories
+- Compile from the source. In this section, we will see both.
+
+Another important thing is the additional libraries required.
+OpenCV-Python requires only **Numpy** (in addition to other dependencies, which we will see later).
+But in this tutorials, we also use **Matplotlib** for some easy and nice plotting purposes (which I feel much better compared to OpenCV).
+Matplotlib is optional, but highly recommended.
+Similarly we will also see **IPython**, an Interactive Python Terminal, which is also highly recommended.
+
+Installing OpenCV-Python from Pre-built Binaries
+------------------------------------------------
+
+This method serves best when using just for programming and developing OpenCV applications.
+
+Install package [python3-opencv](https://packages.ubuntu.com/focal/python3-opencv) with following command in terminal (as root user).
+
+```
+$ sudo apt-get install python3-opencv
+```
+
+Open Python IDLE (or IPython) and type following codes in Python terminal.
+
+```
+import cv2 as cv
+print(cv.__version__)
+```
+
+If the results are printed out without any errors, congratulations !!!
+You have installed OpenCV-Python successfully.
+
+It is quite easy. But there is a problem with this.
+Apt repositories may not contain the latest version of OpenCV always.
+For example, at the time of writing this tutorial, apt repository contains 2.4.8 while latest OpenCV version is 3.x.
+With respect to Python API, latest version will always contain much better support and latest bug fixes.
+
+So for getting latest source codes preference is next method, i.e. compiling from source.
+Also at some point in time, if you want to contribute to OpenCV, you will need this.
+
+Building OpenCV from source
+---------------------------
+
+Compiling from source may seem a little complicated at first, but once you succeeded in it, there is nothing complicated.
+
+First we will install some dependencies.
+Some are required, some are optional.
+You can skip optional dependencies if you don't want.
+
+### Required build dependencies
+
+We need **CMake** to configure the installation, **GCC** for compilation, **Python-devel** and
+**Numpy** for building Python bindings etc.
+
+```
+sudo apt-get install cmake
+sudo apt-get install gcc g++
+```
+to support python2:
+
+```
+sudo apt-get install python-dev python-numpy
+```
+
+to support python3:
+
+```
+sudo apt-get install python3-dev python3-numpy
+```
+
+Next we need **GTK** support for GUI features, Camera support (v4l), Media Support
+(ffmpeg, gstreamer) etc.
+
+```
+sudo apt-get install libavcodec-dev libavformat-dev libswscale-dev
+sudo apt-get install libgstreamer-plugins-base1.0-dev libgstreamer1.0-dev
+```
+
+to support gtk2:
+```
+sudo apt-get install libgtk2.0-dev
+```
+
+to support gtk3:
+```
+sudo apt-get install libgtk-3-dev
+```
+
+### Optional Dependencies
+
+Above dependencies are sufficient to install OpenCV in your Ubuntu machine.
+But depending upon your requirements, you may need some extra dependencies.
+A list of such optional dependencies are given below. You can either leave it or install it, your call :)
+
+OpenCV comes with supporting files for image formats like PNG, JPEG, JPEG2000, TIFF, WebP etc.
+But it may be a little old.
+If you want to get latest libraries, you can install development files for system libraries of these formats.
+
+```
+sudo apt-get install libpng-dev
+sudo apt-get install libjpeg-dev
+sudo apt-get install libopenexr-dev
+sudo apt-get install libtiff-dev
+sudo apt-get install libwebp-dev
+```
+
+@note If you are using Ubuntu 16.04 you can also install ```libjasper-dev``` to add a system level support for the JPEG2000 format.
+
+### Downloading OpenCV
+
+To download the latest source from OpenCV's [GitHub Repository](https://github.com/opencv/opencv).
+(If you want to contribute to OpenCV choose this. For that, you need to install **Git** first)
+
+```
+$ sudo apt-get install git
+$ git clone https://github.com/opencv/opencv.git
+```
+
+It will create a folder "opencv" in current directory.
+The cloning may take some time depending upon your internet connection.
+
+Now open a terminal window and navigate to the downloaded "opencv" folder.
+Create a new "build" folder and navigate to it.
+
+```
+$ mkdir build
+$ cd build
+```
+
+### Configuring and Installing
+
+Now we have all the required dependencies, let's install OpenCV.
+Installation has to be configured with CMake.
+It specifies which modules are to be installed, installation path, which additional libraries to be used, whether documentation and examples to be compiled etc.
+Most of this work are done automatically with well configured default parameters.
+
+Below command is normally used for configuration of OpenCV library build (executed from build folder):
+
+```
+$ cmake ../
+```
+
+OpenCV defaults assume "Release" build type and installation path is "/usr/local".
+For additional information about CMake options refer to OpenCV @ref tutorial_linux_install "C++ compilation guide":
+
+You should see these lines in your CMake output (they mean that Python is properly found):
+
+```
+--   Python 2:
+--     Interpreter:                 /usr/bin/python2.7 (ver 2.7.6)
+--     Libraries:                   /usr/lib/x86_64-linux-gnu/libpython2.7.so (ver 2.7.6)
+--     numpy:                       /usr/lib/python2.7/dist-packages/numpy/core/include (ver 1.8.2)
+--     packages path:               lib/python2.7/dist-packages
+--
+--   Python 3:
+--     Interpreter:                 /usr/bin/python3.4 (ver 3.4.3)
+--     Libraries:                   /usr/lib/x86_64-linux-gnu/libpython3.4m.so (ver 3.4.3)
+--     numpy:                       /usr/lib/python3/dist-packages/numpy/core/include (ver 1.8.2)
+--     packages path:               lib/python3.4/dist-packages
+```
+
+Now you build the files using "make" command and install it using "make install" command.
+
+```
+$ make
+# sudo make install
+```
+
+Installation is over.
+All files are installed in "/usr/local/" folder.
+Open a terminal and try import "cv2".
+
+```
+import cv2 as cv
+print(cv.__version__)
+```

3rdparty/opencv-4.5.4/doc/py_tutorials/py_setup/py_setup_in_windows/py_setup_in_windows.markdown

@@ -0,0 +1,148 @@
+Install OpenCV-Python in Windows {#tutorial_py_setup_in_windows}
+================================
+
+Goals
+-----
+
+In this tutorial
+    - We will learn to setup OpenCV-Python in your Windows system.
+
+Below steps are tested in a Windows 7-64 bit machine with Visual Studio 2010 and Visual Studio 2012.
+The screenshots shows VS2012.
+
+Installing OpenCV from prebuilt binaries
+----------------------------------------
+
+-#  Below Python packages are to be downloaded and installed to their default locations.
+
+    -#  Python 3.x (3.4+) or Python 2.7.x from [here](https://www.python.org/downloads/).
+
+    -#  Numpy package (for example, using `pip install numpy` command).
+
+    -#  Matplotlib (`pip install matplotlib`) (*Matplotlib is optional, but recommended since we use it a lot in our tutorials*).
+
+-#  Install all packages into their default locations. Python will be installed to `C:/Python27/` in case of Python 2.7.
+
+-#  After installation, open Python IDLE. Enter **import numpy** and make sure Numpy is working fine.
+
+-#  Download latest OpenCV release from [GitHub](https://github.com/opencv/opencv/releases) or
+    [SourceForge site](https://sourceforge.net/projects/opencvlibrary/files/)
+    and double-click to extract it.
+
+-#  Goto **opencv/build/python/2.7** folder.
+
+-#  Copy **cv2.pyd** to **C:/Python27/lib/site-packages**.
+
+-#  Open Python IDLE and type following codes in Python terminal.
+    @code
+        >>> import cv2 as cv
+        >>> print( cv.__version__ )
+    @endcode
+
+If the results are printed out without any errors, congratulations !!! You have installed
+OpenCV-Python successfully.
+
+Building OpenCV from source
+---------------------------
+
+-#  Download and install Visual Studio and CMake.
+
+    -#  [Visual Studio 2012](http://go.microsoft.com/?linkid=9816768)
+
+    -#  [CMake](https://cmake.org/download/)
+
+-#  Download and install necessary Python packages to their default locations
+
+    -#  Python
+
+    -#  Numpy
+
+    @note In this case, we are using 32-bit binaries of Python packages. But if you want to use
+    OpenCV for x64, 64-bit binaries of Python packages are to be installed. Problem is that, there
+    is no official 64-bit binaries of Numpy. You have to build it on your own. For that, you have to
+    use the same compiler used to build Python. When you start Python IDLE, it shows the compiler
+    details. You can get more [information here](http://stackoverflow.com/q/2676763/1134940). So
+    your system must have the same Visual Studio version and build Numpy from source.
+
+    @note Another method to have 64-bit Python packages is to use ready-made Python distributions
+    from third-parties like [Anaconda](http://www.continuum.io/downloads),
+    [Enthought](https://www.enthought.com/downloads/) etc. It will be bigger in size, but will have
+    everything you need. Everything in a single shell. You can also download 32-bit versions also.
+
+-#  Make sure Python and Numpy are working fine.
+
+-#  Download OpenCV source. It can be from
+    [Sourceforge](http://sourceforge.net/projects/opencvlibrary/) (for official release version) or
+    from [Github](https://github.com/opencv/opencv) (for latest source).
+-#  Extract it to a folder, opencv and create a new folder build in it.
+-#  Open CMake-gui (*Start \> All Programs \> CMake-gui*)
+-#  Fill the fields as follows (see the image below):
+
+    -#  Click on **Browse Source...** and locate the opencv folder.
+
+    -#  Click on **Browse Build...** and locate the build folder we created.
+
+    -#  Click on **Configure**.
+
+        ![image](images/Capture1.jpg)
+
+    -#  It will open a new window to select the compiler. Choose appropriate compiler (here,
+        Visual Studio 11) and click **Finish**.
+
+        ![image](images/Capture2.png)
+
+    -#  Wait until analysis is finished.
+
+-#  You will see all the fields are marked in red. Click on the **WITH** field to expand it. It
+    decides what extra features you need. So mark appropriate fields. See the below image:
+
+    ![image](images/Capture3.png)
+
+-#  Now click on **BUILD** field to expand it. First few fields configure the build method. See the
+    below image:
+
+    ![image](images/Capture5.png)
+
+-#  Remaining fields specify what modules are to be built. Since GPU modules are not yet supported
+    by OpenCV-Python, you can completely avoid it to save time (But if you work with them, keep it
+    there). See the image below:
+
+    ![image](images/Capture6.png)
+
+-#  Now click on **ENABLE** field to expand it. Make sure **ENABLE_SOLUTION_FOLDERS** is unchecked
+    (Solution folders are not supported by Visual Studio Express edition). See the image below:
+
+    ![image](images/Capture7.png)
+
+-#  Also make sure that in the **PYTHON** field, everything is filled. (Ignore
+    PYTHON_DEBUG_LIBRARY). See image below:
+
+    ![image](images/Capture80.png)
+
+-#  Finally click the **Generate** button.
+
+-#  Now go to our **opencv/build** folder. There you will find **OpenCV.sln** file. Open it with
+    Visual Studio.
+
+-#  Check build mode as **Release** instead of **Debug**.
+
+-#  In the solution explorer, right-click on the **Solution** (or **ALL_BUILD**) and build it. It
+    will take some time to finish.
+
+-#  Again, right-click on **INSTALL** and build it. Now OpenCV-Python will be installed.
+
+    ![image](images/Capture8.png)
+
+-#  Open Python IDLE and enter 'import cv2 as cv'. If no error, it is installed correctly.
+
+@note We have installed with no other support like TBB, Eigen, Qt, Documentation etc. It would be
+difficult to explain it here. A more detailed video will be added soon or you can just hack around.
+
+Additional Resources
+--------------------
+
+Exercises
+---------
+
+If you have a windows machine, compile the OpenCV from source. Do all kinds of hacks. If you meet
+any problem, visit OpenCV forum and explain your problem.

3rdparty/opencv-4.5.4/doc/py_tutorials/py_setup/py_table_of_contents_setup.markdown

@@ -0,0 +1,22 @@
+Introduction to OpenCV {#tutorial_py_table_of_contents_setup}
+======================
+
+-   @subpage tutorial_py_intro
+
+    Getting Started with
+    OpenCV-Python
+
+-   @subpage tutorial_py_setup_in_windows
+
+    Set Up
+    OpenCV-Python in Windows
+
+-   @subpage tutorial_py_setup_in_fedora
+
+    Set Up
+    OpenCV-Python in Fedora
+
+-   @subpage tutorial_py_setup_in_ubuntu
+
+    Set Up
+    OpenCV-Python in Ubuntu