From 13bc55a015b93cc4fbebf0083cb01fb5c3513225 Mon Sep 17 00:00:00 2001
From: Alexander Alekhin <alexander.alekhin@intel.com>
Date: Mon, 9 Dec 2019 18:24:36 +0300
Subject: [PATCH] calib3d: clarify error messages in collectCalibrationData()

---
 modules/calib3d/src/calibration.cpp | 42 ++++++++++++++++-------------
 1 file changed, 23 insertions(+), 19 deletions(-)

diff --git a/modules/calib3d/src/calibration.cpp b/modules/calib3d/src/calibration.cpp
index 7a426e530d..9c640540f7 100644
--- a/modules/calib3d/src/calibration.cpp
+++ b/modules/calib3d/src/calibration.cpp
@@ -3115,28 +3115,30 @@ static void collectCalibrationData( InputArrayOfArrays objectPoints,
                                     Mat& npoints )
 {
     int nimages = (int)objectPoints.total();
-    int i, j = 0, ni = 0, total = 0;
-    CV_Assert(nimages > 0 && nimages == (int)imagePoints1.total() &&
-        (!imgPtMat2 || nimages == (int)imagePoints2.total()));
+    int total = 0;
+    CV_Assert(nimages > 0);
+    CV_CheckEQ(nimages, (int)imagePoints1.total(), "");
+    if (imgPtMat2)
+        CV_CheckEQ(nimages, (int)imagePoints2.total(), "");
 
-    for( i = 0; i < nimages; i++ )
+    for (int i = 0; i < nimages; i++)
     {
         Mat objectPoint = objectPoints.getMat(i);
         if (objectPoint.empty())
             CV_Error(CV_StsBadSize, "objectPoints should not contain empty vector of vectors of points");
-        ni = objectPoint.checkVector(3, CV_32F);
-        if( ni <= 0 )
+        int numberOfObjectPoints = objectPoint.checkVector(3, CV_32F);
+        if (numberOfObjectPoints <= 0)
             CV_Error(CV_StsUnsupportedFormat, "objectPoints should contain vector of vectors of points of type Point3f");
 
         Mat imagePoint1 = imagePoints1.getMat(i);
         if (imagePoint1.empty())
             CV_Error(CV_StsBadSize, "imagePoints1 should not contain empty vector of vectors of points");
-        int ni1 = imagePoint1.checkVector(2, CV_32F);
-        if( ni1 <= 0 )
+        int numberOfImagePoints = imagePoint1.checkVector(2, CV_32F);
+        if (numberOfImagePoints <= 0)
             CV_Error(CV_StsUnsupportedFormat, "imagePoints1 should contain vector of vectors of points of type Point2f");
-        CV_Assert( ni == ni1 );
+        CV_CheckEQ(numberOfObjectPoints, numberOfImagePoints, "Number of object and image points must be equal");
 
-        total += ni;
+        total += numberOfObjectPoints;
     }
 
     npoints.create(1, (int)nimages, CV_32S);
@@ -3144,7 +3146,7 @@ static void collectCalibrationData( InputArrayOfArrays objectPoints,
     imgPtMat1.create(1, (int)total, CV_32FC2);
     Point2f* imgPtData2 = 0;
 
-    if( imgPtMat2 )
+    if (imgPtMat2)
     {
         imgPtMat2->create(1, (int)total, CV_32FC2);
         imgPtData2 = imgPtMat2->ptr<Point2f>();
@@ -3153,28 +3155,30 @@ static void collectCalibrationData( InputArrayOfArrays objectPoints,
     Point3f* objPtData = objPtMat.ptr<Point3f>();
     Point2f* imgPtData1 = imgPtMat1.ptr<Point2f>();
 
-    for( i = 0; i < nimages; i++, j += ni )
+    for (int i = 0, j = 0; i < nimages; i++)
     {
         Mat objpt = objectPoints.getMat(i);
         Mat imgpt1 = imagePoints1.getMat(i);
-        ni = objpt.checkVector(3, CV_32F);
-        npoints.at<int>(i) = ni;
-        for (int n = 0; n < ni; ++n)
+        int numberOfObjectPoints = objpt.checkVector(3, CV_32F);
+        npoints.at<int>(i) = numberOfObjectPoints;
+        for (int n = 0; n < numberOfObjectPoints; ++n)
         {
             objPtData[j + n] = objpt.ptr<Point3f>()[n];
             imgPtData1[j + n] = imgpt1.ptr<Point2f>()[n];
         }
 
-        if( imgPtData2 )
+        if (imgPtData2)
         {
             Mat imgpt2 = imagePoints2.getMat(i);
-            int ni2 = imgpt2.checkVector(2, CV_32F);
-            CV_Assert( ni == ni2 );
-            for (int n = 0; n < ni2; ++n)
+            int numberOfImage2Points = imgpt2.checkVector(2, CV_32F);
+            CV_CheckEQ(numberOfObjectPoints, numberOfImage2Points, "Number of object and image(2) points must be equal");
+            for (int n = 0; n < numberOfImage2Points; ++n)
             {
                 imgPtData2[j + n] = imgpt2.ptr<Point2f>()[n];
             }
         }
+
+        j += numberOfObjectPoints;
     }
 }