From 65e359c8555100d3f1114636f26fcfe15659daf0 Mon Sep 17 00:00:00 2001
From: wtyuan96 <wtyuan@pku.edu.cn>
Date: Tue, 4 Apr 2023 21:04:09 +0800
Subject: [PATCH] Call cornerSubPix when using OpenCV to detect corners

---
 src/chessboard/Chessboard.cc | 12 +++++++++++-
 1 file changed, 11 insertions(+), 1 deletion(-)

diff --git a/src/chessboard/Chessboard.cc b/src/chessboard/Chessboard.cc
index b2cada6f..c7c2a431 100644
--- a/src/chessboard/Chessboard.cc
+++ b/src/chessboard/Chessboard.cc
@@ -76,7 +76,17 @@ Chessboard::findChessboardCorners(const cv::Mat& image,
 {
     if (useOpenCV)
     {
-        return cv::findChessboardCorners(image, patternSize, corners, flags);
+        bool found = cv::findChessboardCorners(image, patternSize, corners, flags);
+        if (found)
+		{
+			cv::cornerSubPix(image, corners, cv::Size(11, 11), cv::Size(-1,-1),
+							 cv::TermCriteria(CV_TERMCRIT_EPS + CV_TERMCRIT_ITER, 30, 0.1));
+            return true;
+        }
+        else
+        {
+            return false;
+        }
     }
     else
     {