* Clean: replace C style asserts by CV_Assert and CV_DbgAssert
* Try fixing warning on Windows compilation
* Another way trying to fix warnings on Win
* Fixing warnings with some compilers:
Some compilers warn on systematic exit preventing to execute the code that follows.
This is why assert(0) that exits only in debug was working, but not CV_Assert or CV_Error
that exit both in release and debug, even if with different behavior.
In addition, other compilers complain when return 0 is removed from getKey(),
even if before we have a statement leading to systematic exit.
* Disable "unreachable code" warnings for Win compilers so we can use proper CV_Error
fix instable fisheye undistortPoints
* remove artefacts when (un)distorting fisheye images with large distortion coefficient values
* fix fisheye undistortion when theta is close to zero
* add fisheye image undistort and distort test
* Fixed type conversion warnings
* fixed trailing whitespace
Before, when maxCheck was reached in the first descent of a tree, time was still wasted parsing
the next trees till their best leaves whose points were not used at all.
Clarify component statistics documentation
* Change ConnectedComponentsTypes documentation
Change from "algorithm output formats" to "statistics" because it specifies types of statistics, not formats.
* Documentation: clarify component statistics
Explain that ConnectedComponentTypes selects a statistic.
Argument "a" is of type ElementType* that is either int* or float*, while b was double*.
Mixing types prevents the possibility to use SSE or AVX instructions.
On implementation without SIMD instructions, this doesn't show any impact on performance.
Fix cuda11
* use cudnn_version.h to detect version when it is available
* remove nppi from CUDA11
* use ocv_list_filterout
* dnn(cuda): temporary disable CUDNN 8.0