init - 初始化项目

doc/tutorials/introduction/cross_referencing/tutorial_cross_referencing.markdown

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+Cross referencing OpenCV from other Doxygen projects {#tutorial_cross_referencing}
+====================================================
+
+@prev_tutorial{tutorial_transition_guide}
+
+|    |    |
+| -: | :- |
+| Original author | Sebastian Höffner |
+| Compatibility | OpenCV >= 3.3.0 |
+
+@warning
+This tutorial can contain obsolete information.
+
+Cross referencing OpenCV
+------------------------
+
+[Doxygen](http://www.doxygen.nl) is a tool to generate
+documentations like the OpenCV documentation you are reading right now.
+It is used by a variety of software projects and if you happen to use it
+to generate your own documentation, and you are using OpenCV inside your
+project, this short tutorial is for you.
+
+Imagine this warning inside your documentation code:
+
+@code
+/**
+ * @warning This functions returns a cv::Mat.
+ */
+@endcode
+
+Inside your generated documentation this warning will look roughly like this:
+
+@warning This functions returns a %cv::Mat.
+
+While inside the OpenCV documentation the `%cv::Mat` is rendered as a link:
+
+@warning This functions returns a cv::Mat.
+
+To generate links to the OpenCV documentation inside your project, you only
+have to perform two small steps. First download the file
+[opencv.tag](opencv.tag) (right-click and choose "save as...") and place it
+somewhere in your project directory, for example as
+`docs/doxygen-tags/opencv.tag`.
+
+Open your Doxyfile using your favorite text editor and search for the key
+`TAGFILES`. Change it as follows:
+
+@code
+TAGFILES = ./docs/doxygen-tags/opencv.tag=http://docs.opencv.org/4.5.2
+@endcode
+
+If you had other definitions already, you can append the line using a `\`:
+
+@code
+TAGFILES = ./docs/doxygen-tags/libstdc++.tag=https://gcc.gnu.org/onlinedocs/libstdc++/latest-doxygen \
+           ./docs/doxygen-tags/opencv.tag=http://docs.opencv.org/4.5.2
+@endcode
+
+Doxygen can now use the information from the tag file to link to the OpenCV
+documentation. Rebuild your documentation right now!
+
+@note To allow others to also use a *.tag file to link to your documentation,
+set `GENERATE_TAGFILE = html/your_project.tag`. Your documentation will now
+contain a `your_project.tag` file in its root directory.
+
+
+References
+----------
+
+- [Doxygen: Linking to external documentation](http://www.doxygen.nl/manual/external.html)
+- [opencv.tag](opencv.tag)