Computer Vision with OpenCV 3 and Qt5

InputArray, OutputArry, InputOutputArray

You'll notice that most OpenCV functions accept these types of parameters instead of Mat and its similar data types. These are proxy data types used for better readability and data type support. That simply means you can pass any of the following data types to OpenCV functions that except InputArray, OutputArray or InutOutputArray data types:

• Mat
• Mat_<T>
• Matx<T, m, n>
• std::vector<T>
• std::vector<std::vector<T> >
• std::vector<Mat>
• std::vector<Mat_<T> >
• UMat
• std::vector<UMat>
• double

Notice that OpenCV treats standard C++ vectors (std::vector) just like a Mat or a similar class. The more or less obvious reason is that their underlying data structure is more or less the same.

You should never explicitly ...