Merge pull request #5655 from janstarzy:2.4-canny-fix

modules/imgproc/src/canny.cpp

@@ -230,7 +230,7 @@ void cv::Canny( InputArray _src, OutputArray _dst,
         if ((stack_top - stack_bottom) + src.cols > maxsize)
         {
             int sz = (int)(stack_top - stack_bottom);
-            maxsize = maxsize * 3/2;
+            maxsize = std::max(sz + src.cols, maxsize * 3/2);
             stack.resize(maxsize);
             stack_bottom = &stack[0];
             stack_top = stack_bottom + sz;