Use checkVector over "2-point trick"

Fix warnings on MSVC compiler

- reduce unused dependencies

* Fix for Depth Registration. Issue #2234

* Fix style

* Incorporating suggestions. 1. Trailing whitespace 2. Matx33f 3. EXPECT_EQ

* test: use Matx33f ctor

SinusoidalPattern::unwrapPhaseMap now takes an InputArray instead of InputArrayOfArrays to correct a Python binding problem
present a scriptable HistogramPhaseUnwrapping::create

replicate C++ structured_light test in Python

PhaseUnwrapping now init unwrappedPhase so pixel outside the mask area are set to 0

python binding for HistogramPhaseUnwrapping::Params to use HistogramPhaseUnwrapping::create

reformatted the documentation

* issue-16736: quick step towards moving SIFT from non-free to free. Moves
include, tests, and implementation to free area.

* FREAK : better rounding off for weighted dx and dy of orientation pairs

* updated using cvRound

* cvRound modified

* Add overload method and fix typos in omnidir (1/2)

Addresses part of https://github.com/opencv/opencv/issues/16601

* Add overload method in omnidir (2/2)

Addresses part of https://github.com/opencv/opencv/issues/16601

* fixed typo

* fixed document

Fixes error occurs in cv::ppf_match_3d::ICP::registerModelToScene()

* corrected out of range error

* remove unnecessary changes

* fix warning

Update test_hdr.cpp

Update test_hdr.cpp

Harmonise bibtex formatting. Sort entries alphabetically by the last name of the first paper author.

* ximgproc(test): createSuperpixelSLIC smoke test

* ximgproc: don't use 'operator+()' with empty cv::Mat

backport commit 13f76375