From b17d16623a1f3050e28f20048da12a556f055305 Mon Sep 17 00:00:00 2001
From: Matt Bennett <m.bennett@uncrewed.tech>
Date: Wed, 4 Sep 2019 15:33:03 +0100
Subject: [PATCH] Prevent empty _Jo matrix multiplication when using
 calibrateCameraRO with iFixedPoint > 0

---
 modules/calib3d/src/calibration.cpp | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/modules/calib3d/src/calibration.cpp b/modules/calib3d/src/calibration.cpp
index ace1322dbf..b663a63544 100644
--- a/modules/calib3d/src/calibration.cpp
+++ b/modules/calib3d/src/calibration.cpp
@@ -1588,7 +1588,7 @@ static double cvCalibrateCamera2Internal( const CvMat* objectPoints,
     Mat _Je( maxPoints*2, 6, CV_64FC1 );
     Mat _err( maxPoints*2, 1, CV_64FC1 );
 
-    const bool allocJo = (solver.state == CvLevMarq::CALC_J) || stdDevs;
+    const bool allocJo = (solver.state == CvLevMarq::CALC_J) || stdDevs || releaseObject;
     Mat _Jo = allocJo ? Mat( maxPoints*2, maxPoints*3, CV_64FC1, Scalar(0) ) : Mat();
 
     if(flags & CALIB_USE_LU) {