Update find ellipses

modules/ximgproc/include/opencv2/ximgproc/find_ellipses.hpp

@@ -17,8 +17,8 @@ namespace ximgproc {
 @brief Finds ellipses fastly in an image using projective invariant pruning.
 *
 * The function detects ellipses in images using projective invariant pruning.
-* For more details about this implementation, please see
-* [JIA2017FAST]  Jia, Qi et al, (2017).
+* For more details about this implementation, please see @cite jia2017fast
+* Jia, Qi et al, (2017).
 * A Fast Ellipse Detector using Projective Invariant Pruning. IEEE Transactions on Image Processing.
 *
 @param image input image, could be gray or color.

modules/ximgproc/samples/find_ellipses.py

@@ -0,0 +1,46 @@
+#!/usr/bin/python
+
+'''
+This example illustrates how to use cv.ximgproc.findEllipses function.
+
+Usage:
+    find_ellipses.py [<image_name>]
+    image argument defaults to stuff.jpg
+'''
+
+# Python 2/3 compatibility
+from __future__ import print_function
+
+import numpy as np
+import cv2 as cv
+import sys
+import math
+
+def main():
+    try:
+        fn = sys.argv[1]
+    except IndexError:
+        fn = 'stuff.jpg'
+
+    src = cv.imread(cv.samples.findFile(fn))
+    cv.imshow("source", src)
+
+    ells = cv.ximgproc.findEllipses(src,scoreThreshold = 0.4, reliabilityThreshold = 0.7, centerDistanceThreshold = 0.02)
+
+    if ells is not None:
+        for i in range(len(ells)):
+            center = (int(ells[i][0][0]), int(ells[i][0][1]))
+            axes = (int(ells[i][0][2]),int(ells[i][0][3]))
+            angle = ells[i][0][5] * 180 / math.pi
+            color = (0, 0, 255)
+            cv.ellipse(src, center, axes, angle,0, 360, color, 2, cv.LINE_AA)
+
+    cv.imshow("detected ellipses", src)
+    cv.waitKey(0)
+    print('Done')
+
+
+if __name__ == '__main__':
+    print(__doc__)
+    main()
+    cv.destroyAllWindows()

modules/ximgproc/src/find_ellipses.cpp

@@ -310,11 +310,11 @@ float EllipseDetectorImpl::getMedianSlope(std::vector<Point2f> &med, Point2f &ce
     // centers  : centroid of the points in med
     // slopes	: vector of the slopes
 
-    unsigned pointCount = med.size();
+    size_t pointCount = med.size();
     // CV_Assert(pointCount >= 2);
 
-    unsigned halfSize = pointCount >> 1;
-    unsigned quarterSize = halfSize >> 1;
+    size_t halfSize = pointCount >> 1;
+    size_t quarterSize = halfSize >> 1;
 
     std::vector<float> xx, yy;
     slopes.reserve(halfSize);
@@ -1341,7 +1341,7 @@ void EllipseDetectorImpl::preProcessing(Mat1b &image, Mat1b &dp, Mat1b &dn) {
         }
 
         const int CANNY_SHIFT = 15;
-        const float TAN22_5 = 0.4142135623730950488016887242097; // tan(22.5) = sqrt(2) - 1
+        const float TAN22_5 = 0.4142135623730950488016887242097f; // tan(22.5) = sqrt(2) - 1
         const int TG22 = (int) (TAN22_5 * (1 << CANNY_SHIFT) + 0.5);
 
         // #define CANNY_PUSH(d)    *(d) = (uchar)2, *stack_top++ = (d)
@@ -1723,8 +1723,8 @@ void EllipseDetectorImpl::findEllipses(Point2f &center, VP &edge_i, VP &edge_j,
     }
 
     // find peak in N and K accumulator
-    int iN = std::distance(accN, std::max_element(accN, accN + ACC_N_SIZE));
-    int iK = std::distance(accR, std::max_element(accR, accR + ACC_R_SIZE)) + 90;
+    int iN = (int)std::distance(accN, std::max_element(accN, accN + ACC_N_SIZE));
+    int iK = (int)std::distance(accR, std::max_element(accR, accR + ACC_R_SIZE)) + 90;
 
     // recover real values
     auto fK = float(iK);
@@ -1767,7 +1767,7 @@ void EllipseDetectorImpl::findEllipses(Point2f &center, VP &edge_i, VP &edge_j,
     }
 
     // find peak in A accumulator
-    int A = std::distance(accA, std::max_element(accA, accA + ACC_A_SIZE));
+    int A = (int)std::distance(accA, std::max_element(accA, accA + ACC_A_SIZE));
     auto fA = float(A);
 
     // find B value. See Eq [23] in the paper
@@ -1974,15 +1974,14 @@ void findEllipses(
     edi.detect(grayImage, ellipseResults);
 
     // convert - ellipse format to std::vector<Vec6f>
-    auto ellipseSize = unsigned(ellipseResults.size());
-    Mat _ellipses(1, ellipseSize, CV_32FC(6));
-    for (unsigned i = 0; i < ellipseSize; i++) {
+    std::vector<Vec6f> _ellipses;
+    for (size_t i = 0; i < ellipseResults.size(); i++) {
         Ellipse tmpEll = ellipseResults[i];
         Vec6f tmpVec(tmpEll.center.x, tmpEll.center.y, tmpEll.a, tmpEll.b, tmpEll.score,
                      tmpEll.radius);
-        _ellipses.at<Vec6f>(i) = tmpVec;
+        _ellipses.push_back(tmpVec);
     }
-    _ellipses.copyTo(ellipses);
+    Mat(_ellipses).copyTo(ellipses);
 }
 } // namespace ximgproc
 } // namespace cv