Add optional template mask for findTransformECC #27952
Supersedes #22997
**Summary**
Add optional template mask support to findTransformECC so that only pixels valid in both the template and the image are used in ECC. Backward compatibility is preserved (existing signatures unchanged; one new overload adds templateMask).
**Motivation**
- Real-world frames often contain moving foreground artifacts (e.g., a football over a static field). Masking the object in one frame only is insufficient because its position changes independently of the background. Since we don’t know the warp a priori, we can’t back-project a single mask across frames. The correct approach is to supply both masks and take their intersection.
- Templates may include uninformative/low-texture or noisy regions, or partial overlaps with other objects. Excluding such regions from the alignment improves robustness and convergence.
This PR completes and replaces https://github.com/opencv/opencv/pull/22997
### Pull Request Readiness Checklist
See details at https://github.com/opencv/opencv/wiki/How_to_contribute#making-a-good-pull-request
- [x] I agree to contribute to the project under Apache 2 License.
- [x] To the best of my knowledge, the proposed patch is not based on a code under GPL or another license that is incompatible with OpenCV
- [ ] The PR is proposed to the proper branch
- [ ] There is a reference to the original bug report and related work
- [ ] There is accuracy test, performance test and test data in opencv_extra repository, if applicable
Patch to opencv_extra has the same branch name.
- [ ] The feature is well documented and sample code can be built with the project CMake
Fix unsigned int bug in computeECC
* address issue with unsigned ints in computeEcc
* remove additional logic checking firstOctave
* use swap instead of same src/dst
* simplify the unsigned check logic
New computeECC function, and updated findTransformECC function to make gaussian filtering optional (#13837)
* fix for https://github.com/opencv/opencv/issues/12432 with doc and tests
* Added doc string for new parameter.
* Fixes suggested by Alalek for getting around ABI incompatibility.
* Update to docstring, to remove parameter that isn't relevant.
* More updates based on Alalek's usggestions.
- removed tr1 usage (dropped in C++17)
- moved includes of vector/map/iostream/limits into ts.hpp
- require opencv_test + anonymous namespace (added compile check)
- fixed norm() usage (must be from cvtest::norm for checks) and other conflict functions
- added missing license headers
Tests of the mask are also included.
This is useful for registering a non-square image against a non-square
template.
This also needs to relax a sanity check as per
https://github.com/Itseez/opencv/pull/3851
Dmytro Dadyka
Danny
AKAMath
Alexander Alekhin
Vitaly Tuzov
Krishnaraj Bhat
Owen Healy
Ilya Lavrenov
Andrey Kamaev
Georgios Evangelidis