Merge pull request #24595 from MaximSmolskiy:fix-typo-inChessBoardDetector-generateQuads

Fix typo in ChessBoardDetector::generateQuads #24595

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- [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
- [x] 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

modules/calib3d/src/calibinit.cpp

@@ -1730,8 +1730,8 @@ void ChessBoardDetector::generateQuads(const cv::Mat& image_, int flags)
     all_quads.deallocate();
     all_corners.deallocate();
 
-    // empiric bound for minimal allowed perimeter for squares
-    int min_size = 25; //cvRound( image->cols * image->rows * .03 * 0.01 * 0.92 );
+    // empiric bound for minimal allowed area for squares
+    const int min_area = 25; //cvRound( image->cols * image->rows * .03 * 0.01 * 0.92 );
 
     bool filterQuads = (flags & CALIB_CB_FILTER_QUADS) != 0;
 
@@ -1759,7 +1759,7 @@ void ChessBoardDetector::generateQuads(const cv::Mat& image_, int flags)
         const std::vector<Point>& contour = contours[idx];
 
         Rect contour_rect = boundingRect(contour);
-        if (contour_rect.area() < min_size)
+        if (contour_rect.area() < min_area)
             continue;
 
         std::vector<Point> approx_contour;
@@ -1803,7 +1803,7 @@ void ChessBoardDetector::generateQuads(const cv::Mat& image_, int flags)
             // than rectangular and which are big enough
             double d3 = sqrt(normL2Sqr<double>(pt[0] - pt[1]));
             double d4 = sqrt(normL2Sqr<double>(pt[1] - pt[2]));
-            if (!(d3*4 > d4 && d4*4 > d3 && d3*d4 < area*1.5 && area > min_size &&
+            if (!(d3*4 > d4 && d4*4 > d3 && d3*d4 < area*1.5 && area > min_area &&
                 d1 >= 0.15 * p && d2 >= 0.15 * p))
                 continue;
         }