Hough many circles (#10232)
* Add Hui's optimization. Merge with latest changes in OpenCV.
* Use conditional compilation instead of a runtime flag.
* Whitespace.
* Create the sequence for the nonzero edge pixels only if using that approach.
* Improve performance for finding very large numbers of circles
* Return the circles with the larger accumulator values first, as per API documentation.
Use a separate step to check distance between circles. Allows circles to be sorted by strength first. Avoids locking in EstimateRadius which was slowing it down.
Return centers only if maxRadius == 0 as per API documentation.
* Sort the circles so results are deterministic. Otherwise the order of circles with the same strength depends on parallel processing completion order.
* Add test for HoughCircles.
* Add beads test.
* Wrap the non-zero points structure in a common interface so the code can use either a vector or a matrix.
* Remove the special case for skipping the radius search if maxRadius==0.
* Add performance tests.
* Use NULL instead of nullptr.
OpenCV should compile with C++98 compiler.
* Put test suite name first.
Use different test suite names for each test to avoid an error from the test runner.
* Address build bot errors and warnings.
* Skip radius search if maxRadius < 0.
* Dynamically switch to NZPointList when it will be faster than NZPointSet.
* Fix compile error: missing 'typename' prior to dependent type name.
* Fix compile error: missing 'typename' prior to dependent type name.
This time fix it the non C++ 11 way.
* Fix compile error: no type named 'const_reference' in 'class cv::NZPointList'
* Disable ManySmallCircles tests. Failing on Mac.
* Change beads image to JPEG for smaller file size.
Try enabling the ManySmallCircles tests again.
* Remove ManySmallCircles tests. They are failing on the Mac build.
* Fix expectations to check all circles.
* Changing case on a case-insensitive file system
Step 1: remove the old file names
* Changing case on a case-insensitive file system
Step 2: add them back with the new names
* Fix cmpAccum function to be strictly weak ordered.
* Add tests for many small circles.
* imgproc(perf): fix HoughCircles tests
* imgproc(houghCircles): refactor code
- simplify NZPointList
- drop broken (de-synchronization of 'current'/'mi' fields) NZPointSet iterator
- NZPointSet iterator is replaced to direct area scan
- use SIMD intrinsics
- avoid std exceptions (build for embedded systems)
Tom Becker
592f8d8c1b