From fa3c6821ac66d939ecba42132be37fbf59f14708 Mon Sep 17 00:00:00 2001
From: Vadim Pisarevsky <no@email>
Date: Sun, 13 Jun 2010 16:12:50 +0000
Subject: [PATCH] handle the non-detected board case in
 cv::drawChessboardCorners.

---
 modules/calib3d/src/calibinit.cpp | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/modules/calib3d/src/calibinit.cpp b/modules/calib3d/src/calibinit.cpp
index d9e26ef34..66125b9cc 100644
--- a/modules/calib3d/src/calibinit.cpp
+++ b/modules/calib3d/src/calibinit.cpp
@@ -1909,6 +1909,8 @@ void drawChessboardCorners( Mat& image, Size patternSize,
                             const Mat& corners,
                             bool patternWasFound )
 {
+    if( corners.cols == 0 || corners.rows == 0 )
+        return;
     CvMat _image = image;
     CV_Assert((corners.cols == 1 || corners.rows == 1) &&
               corners.type() == CV_32FC2 && corners.isContinuous());