Issue 1:
System information (version)

OpenCV => 4.1.1

Operating System / Platform => Android/ Lenovo Z5

Compiler => Cmake

Detailed description

I have a caffe model of mtcnn and a caffe model of sphereface. I have built a pipeline that takes an image and produces an embedding of the face. Pipeline is written in c++. On my CPU i5 processor opencv dnn is loading the models and is taking 100 milliseconds for processing. Exactly same code when i deploy on android takes around 20 times more time for execution. I have tried compiling opencv on android using MKL and openblas but i found no different at all in processing speed. Here is my cmake configuration:

"-DBUILD_opencv_world=ON -DBUILD_opencv_gapi=OFF -DWITH_NVCUVID=OFF " +

"-DWITH_CUBLAS=ON -DWITH_MKL=ON -DMKL_USE_MULTITHREAD=ON -DMKL_WITH_TBB=ON -DWITH_TBB=ON " +

"-DINSTALL_TESTS=ON -DINSTALL_C_EXAMPLES=ON -DBUILD_EXAMPLES=ON -DWITH_OPENGL=ON" +

"-DOPENCV_ENABLE_NONFREE=ON -DWITH_NVCUVID=ON -DWITH_MFX=ON"

Steps to reproduce

Simply take any caffe model and run it on CPU and then use the same code android. Android processing will be a lot slower. I am expecting this to be slow on android but it is absurdly slower in my case. I can expect 4 to 5 times slower performance but 20 times is just not acceptable.

Issue 2:
System information (version)

OpenCV => 4.2.0

Operating System / Platform => windows 10

Compiler => MSVC

Detailed description

I am totally new to OpenCV and I've learnt C++ just to start messing with OpenCV, even though I'm new to the language and the library I've done my reading and think I have a handle on the language, the library however is a different story. Anyways, on trying out the tutorial code from the website I noticed a ton of warnings in visual studio over simple image I/O. I was wondering if this is a normal occurrence and sought an answer on stackoverflow, the general consensus was to raise the issues here.

Steps to reproduce

#include<opencv2/opencv.hpp>
#include<iostream>

int main() {
std::string image_name("images/Screenshot_296.png");
cv::Mat image = cv::imread(image_name, cv::IMREAD_COLOR);

cv::namedWindow("Window", cv::WINDOW_AUTOSIZE);

cv::imshow("Window", image);

cv::waitKey(0);
return 0;
}

Errors in MSVC:

Severity	Code	Description	Project	File	Line	Suppression State
Warning	C6385	Reading invalid data from 'this->val': the readable size is '24' bytes, but 'i' bytes may be read.	OpenCV_Tutorials	C:\Users\nayja\Desktop\OpenCV Projects\opencv\build\include\opencv2\core\matx.hpp	1124
Warning	C6385	Reading invalid data from 'this->val': the readable size is '12' bytes, but 'i' bytes may be read.	OpenCV_Tutorials	C:\Users\nayja\Desktop\OpenCV Projects\opencv\build\include\opencv2\core\matx.hpp	1124
Warning	C6385	Reading invalid data from 'this->val': the readable size is '16' bytes, but 'i' bytes may be read.	OpenCV_Tutorials	C:\Users\nayja\Desktop\OpenCV Projects\opencv\build\include\opencv2\core\matx.hpp	1124
Warning	C6385	Reading invalid data from 'this->val': the readable size is '32' bytes, but 'i' bytes may be read.	OpenCV_Tutorials	C:\Users\nayja\Desktop\OpenCV Projects\opencv\build\include\opencv2\core\matx.hpp	1124
Warning	C6385	Reading invalid data from 'this->val': the readable size is '8' bytes, but 'i' bytes may be read.	OpenCV_Tutorials	C:\Users\nayja\Desktop\OpenCV Projects\opencv\build\include\opencv2\core\matx.hpp	1124
Warning	C6297	Arithmetic overflow: 32-bit value is shifted, then cast to 64-bit value. Results might not be an expected value.	OpenCV_Tutorials	C:\Users\nayja\Desktop\OpenCV Projects\opencv\build\include\opencv2\core\cuda.inl.hpp	301
Warning	C6297	Arithmetic overflow: 32-bit value is shifted, then cast to 64-bit value. Results might not be an expected value.	OpenCV_Tutorials	C:\Users\nayja\Desktop\OpenCV Projects\opencv\build\include\opencv2\core\cuda.inl.hpp	482
Warning	C6297	Arithmetic overflow: 32-bit value is shifted, then cast to 64-bit value. Results might not be an expected value.	OpenCV_Tutorials	C:\Users\nayja\Desktop\OpenCV Projects\opencv\build\include\opencv2\core\mat.inl.hpp	581
Warning	C6297	Arithmetic overflow: 32-bit value is shifted, then cast to 64-bit value. Results might not be an expected value.	OpenCV_Tutorials	C:\Users\nayja\Desktop\OpenCV Projects\opencv\build\include\opencv2\core\mat.inl.hpp	610
Warning	C6297	Arithmetic overflow: 32-bit value is shifted, then cast to 64-bit value. Results might not be an expected value.	OpenCV_Tutorials	C:\Users\nayja\Desktop\OpenCV Projects\opencv\build\include\opencv2\core\mat.inl.hpp	2245
Warning	C6297	Arithmetic overflow: 32-bit value is shifted, then cast to 64-bit value. Results might not be an expected value.	OpenCV_Tutorials	C:\Users\nayja\Desktop\OpenCV Projects\opencv\build\include\opencv2\core\utility.hpp	575
Warning	C6294	Ill-defined for-loop: initial condition does not satisfy test. Loop body not executed.	OpenCV_Tutorials	C:\Users\nayja\Desktop\OpenCV Projects\opencv\build\include\opencv2\core\matx.hpp	559
Warning	C6294	Ill-defined for-loop: initial condition does not satisfy test. Loop body not executed.	OpenCV_Tutorials	C:\Users\nayja\Desktop\OpenCV Projects\opencv\build\include\opencv2\core\matx.hpp	567
Warning	C6294	Ill-defined for-loop: initial condition does not satisfy test. Loop body not executed.	OpenCV_Tutorials	C:\Users\nayja\Desktop\OpenCV Projects\opencv\build\include\opencv2\core\matx.hpp	575
Warning	C6269	Possibly incorrect order of operations: dereference ignored.	OpenCV_Tutorials	C:\Users\nayja\Desktop\OpenCV Projects\opencv\build\include\opencv2\flann\any.h	97
Warning	C6201	Index '2' is out of valid index range '0' to '1' for possibly stack allocated buffer 'this->val'.	OpenCV_Tutorials	C:\Users\nayja\Desktop\OpenCV Projects\opencv\build\include\opencv2\core\matx.hpp	559
Warning	C6201	Index '3' is out of valid index range '0' to '2' for possibly stack allocated buffer 'this->val'.	OpenCV_Tutorials	C:\Users\nayja\Desktop\OpenCV Projects\opencv\build\include\opencv2\core\matx.hpp	567
Warning	C6201	Index '4' is out of valid index range '0' to '3' for possibly stack allocated buffer 'this->val'.	OpenCV_Tutorials	C:\Users\nayja\Desktop\OpenCV Projects\opencv\build\include\opencv2\core\matx.hpp	575
Warning	C6011	Dereferencing NULL pointer 'data+step.p[0]*i0'.	OpenCV_Tutorials	C:\Users\nayja\Desktop\OpenCV Projects\opencv\build\include\opencv2\core\mat.inl.hpp	1181
Warning	C6011	Dereferencing NULL pointer 'this->data+this->step.p[0]*i0'.	OpenCV_Tutorials	C:\Users\nayja\Desktop\OpenCV Projects\opencv\build\include\opencv2\core\mat.inl.hpp	1943
Warning	C6011	Dereferencing NULL pointer 'm'. See line 2686 for an earlier location where this can occur	OpenCV_Tutorials	C:\Users\nayja\Desktop\OpenCV Projects\opencv\build\include\opencv2\core\mat.inl.hpp	2689
Warning	C6011	Dereferencing NULL pointer 'm'. See line 2700 for an earlier location where this can occur	OpenCV_Tutorials	C:\Users\nayja\Desktop\OpenCV Projects\opencv\build\include\opencv2\core\mat.inl.hpp	2703
Warning	C26812	The enum type 'cv::cuda::HostMem::AllocType' is unscoped. Prefer 'enum class' over 'enum' (Enum.3).	OpenCV_Tutorials	C:\Users\nayja\Desktop\OpenCV Projects\opencv\build\include\opencv2\core\cuda.inl.hpp	385
Warning	C26812	The enum type 'cv::cuda::FeatureSet' is unscoped. Prefer 'enum class' over 'enum' (Enum.3).	OpenCV_Tutorials	C:\Users\nayja\Desktop\OpenCV Projects\opencv\build\include\opencv2\core\cuda.inl.hpp	605
Warning	C26812	The enum type 'cv::UMatUsageFlags' is unscoped. Prefer 'enum class' over 'enum' (Enum.3).	OpenCV_Tutorials	C:\Users\nayja\Desktop\OpenCV Projects\opencv\build\include\opencv2\core\mat.inl.hpp	3648
Warning	C26812	The enum type 'cvflann::flann_algorithm_t' is unscoped. Prefer 'enum class' over 'enum' (Enum.3).	OpenCV_Tutorials	C:\Users\nayja\Desktop\OpenCV Projects\opencv\build\include\opencv2\flann\kdtree_index.h	59
Warning	C26812	The enum type 'cvflann::flann_centers_init_t' is unscoped. Prefer 'enum class' over 'enum' (Enum.3).	OpenCV_Tutorials	C:\Users\nayja\Desktop\OpenCV Projects\opencv\build\include\opencv2\flann\kmeans_index.h	59
Warning	C26812	The enum type 'cvflann::lsh::LshTable<unsigned char>::SpeedLevel' is unscoped. Prefer 'enum class' over 'enum' (Enum.3).	OpenCV_Tutorials	C:\Users\nayja\Desktop\OpenCV Projects\opencv\build\include\opencv2\flann\lsh_table.h	279
Warning	C26812	The enum type 'cvflann::flann_datatype_t' is unscoped. Prefer 'enum class' over 'enum' (Enum.3).	OpenCV_Tutorials	C:\Users\nayja\Desktop\OpenCV Projects\opencv\build\include\opencv2\flann\saving.h	51
Warning	C26812	The enum type 'cv::DetectionBasedTracker::ObjectStatus' is unscoped. Prefer 'enum class' over 'enum' (Enum.3).	OpenCV_Tutorials	C:\Users\nayja\Desktop\OpenCV Projects\opencv\build\include\opencv2\objdetect\detection_based_tracker.hpp	154
Warning	C26812	The enum type 'cv::detail::WaveCorrectKind' is unscoped. Prefer 'enum class' over 'enum' (Enum.3).	OpenCV_Tutorials	C:\Users\nayja\Desktop\OpenCV Projects\opencv\build\include\opencv2\stitching.hpp	192
Warning	C26812	The enum type 'cv::detail::DpSeamFinder::CostFunction' is unscoped. Prefer 'enum class' over 'enum' (Enum.3).	OpenCV_Tutorials	C:\Users\nayja\Desktop\OpenCV Projects\opencv\build\include\opencv2\stitching\detail\seam_finders.hpp	125
Warning	C26812	The enum type 'cv::videostab::MotionModel' is unscoped. Prefer 'enum class' over 'enum' (Enum.3).	OpenCV_Tutorials	C:\Users\nayja\Desktop\OpenCV Projects\opencv\build\include\opencv2\videostab\motion_core.hpp	102
Warning	C26495	Variable 'cv::float16_t::w' is uninitialized. Always initialize a member variable (type.6).	OpenCV_Tutorials	C:\Users\nayja\Desktop\OpenCV Projects\opencv\build\include\opencv2\core\cvdef.h	741
Warning	C26495	Variable 'cv::debug_build_guard::_InputArray::flags' is uninitialized. Always initialize a member variable (type.6).	OpenCV_Tutorials	C:\Users\nayja\Desktop\OpenCV Projects\opencv\build\include\opencv2\core\mat.inl.hpp	116
Warning	C26495	Variable 'cv::debug_build_guard::_InputArray::obj' is uninitialized. Always initialize a member variable (type.6).	OpenCV_Tutorials	C:\Users\nayja\Desktop\OpenCV Projects\opencv\build\include\opencv2\core\mat.inl.hpp	116
Warning	C26495	Variable 'cv::MatStep::buf' is uninitialized. Always initialize a member variable (type.6).	OpenCV_Tutorials	C:\Users\nayja\Desktop\OpenCV Projects\opencv\build\include\opencv2\core\mat.inl.hpp	1554
Warning	C26495	Variable 'cv::MatStep::buf' is uninitialized. Always initialize a member variable (type.6).	OpenCV_Tutorials	C:\Users\nayja\Desktop\OpenCV Projects\opencv\build\include\opencv2\core\mat.inl.hpp	1560
Warning	C26495	Variable 'cv::Matx<double,3,1>::val' is uninitialized. Always initialize a member variable (type.6).	OpenCV_Tutorials	C:\Users\nayja\Desktop\OpenCV Projects\opencv\build\include\opencv2\core\matx.hpp	542
Warning	C26495	Variable 'cv::Matx<double,4,1>::val' is uninitialized. Always initialize a member variable (type.6).	OpenCV_Tutorials	C:\Users\nayja\Desktop\OpenCV Projects\opencv\build\include\opencv2\core\matx.hpp	542
Warning	C26495	Variable 'cv::Matx<float,3,1>::val' is uninitialized. Always initialize a member variable (type.6).	OpenCV_Tutorials	C:\Users\nayja\Desktop\OpenCV Projects\opencv\build\include\opencv2\core\matx.hpp	542
Warning	C26495	Variable 'cv::Matx<double,3,1>::val' is uninitialized. Always initialize a member variable (type.6).	OpenCV_Tutorials	C:\Users\nayja\Desktop\OpenCV Projects\opencv\build\include\opencv2\core\matx.hpp	668
Warning	C26495	Variable 'cv::Matx<double,4,1>::val' is uninitialized. Always initialize a member variable (type.6).	OpenCV_Tutorials	C:\Users\nayja\Desktop\OpenCV Projects\opencv\build\include\opencv2\core\matx.hpp	668
Warning	C26495	Variable 'cv::Matx<float,3,1>::val' is uninitialized. Always initialize a member variable (type.6).	OpenCV_Tutorials	C:\Users\nayja\Desktop\OpenCV Projects\opencv\build\include\opencv2\core\matx.hpp	668
Warning	C26495	Variable 'cv::Matx<double,4,1>::val' is uninitialized. Always initialize a member variable (type.6).	OpenCV_Tutorials	C:\Users\nayja\Desktop\OpenCV Projects\opencv\build\include\opencv2\core\matx.hpp	858
Warning	C26495	Variable 'cv::AutoBuffer<__int64,1>::buf' is uninitialized. Always initialize a member variable (type.6).	OpenCV_Tutorials	C:\Users\nayja\Desktop\OpenCV Projects\opencv\build\include\opencv2\core\utility.hpp	974
Warning	C26495	Variable 'cv::AutoBuffer<__int64,1>::ptr' is uninitialized. Always initialize a member variable (type.6).	OpenCV_Tutorials	C:\Users\nayja\Desktop\OpenCV Projects\opencv\build\include\opencv2\core\utility.hpp	974
Warning	C26495	Variable 'cv::AutoBuffer<double,1>::buf' is uninitialized. Always initialize a member variable (type.6).	OpenCV_Tutorials	C:\Users\nayja\Desktop\OpenCV Projects\opencv\build\include\opencv2\core\utility.hpp	974
Warning	C26495	Variable 'cv::AutoBuffer<double,1>::ptr' is uninitialized. Always initialize a member variable (type.6).	OpenCV_Tutorials	C:\Users\nayja\Desktop\OpenCV Projects\opencv\build\include\opencv2\core\utility.hpp	974
Warning	C26495	Variable 'cv::dnn::experimental_dnn_34_v15::DictValue::<unnamed-tag>::pd' is uninitialized. Always initialize a member variable (type.6).	OpenCV_Tutorials	C:\Users\nayja\Desktop\OpenCV Projects\opencv\build\include\opencv2\dnn\dnn.inl.hpp	239
Warning	C26495	Variable 'cv::dnn::experimental_dnn_34_v15::DictValue::<unnamed-tag>::pi' is uninitialized. Always initialize a member variable (type.6).	OpenCV_Tutorials	C:\Users\nayja\Desktop\OpenCV Projects\opencv\build\include\opencv2\dnn\dnn.inl.hpp	239
Warning	C26495	Variable 'cv::dnn::experimental_dnn_34_v15::DictValue::<unnamed-tag>::ps' is uninitialized. Always initialize a member variable (type.6).	OpenCV_Tutorials	C:\Users\nayja\Desktop\OpenCV Projects\opencv\build\include\opencv2\dnn\dnn.inl.hpp	239
Warning	C26495	Variable 'cv::dnn::experimental_dnn_34_v15::DictValue::<unnamed-tag>::pv' is uninitialized. Always initialize a member variable (type.6).	OpenCV_Tutorials	C:\Users\nayja\Desktop\OpenCV Projects\opencv\build\include\opencv2\dnn\dnn.inl.hpp	239
Warning	C26495	Variable 'cvflann::lsh::LshStats::bucket_size_max_' is uninitialized. Always initialize a member variable (type.6).	OpenCV_Tutorials	C:\Users\nayja\Desktop\OpenCV Projects\opencv\build\include\opencv2\flann\lsh_table.h	96
Warning	C26495	Variable 'cvflann::lsh::LshStats::bucket_size_mean_' is uninitialized. Always initialize a member variable (type.6).	OpenCV_Tutorials	C:\Users\nayja\Desktop\OpenCV Projects\opencv\build\include\opencv2\flann\lsh_table.h	96
Warning	C26495	Variable 'cvflann::lsh::LshStats::bucket_size_median_' is uninitialized. Always initialize a member variable (type.6).	OpenCV_Tutorials	C:\Users\nayja\Desktop\OpenCV Projects\opencv\build\include\opencv2\flann\lsh_table.h	96
Warning	C26495	Variable 'cvflann::lsh::LshStats::bucket_size_min_' is uninitialized. Always initialize a member variable (type.6).	OpenCV_Tutorials	C:\Users\nayja\Desktop\OpenCV Projects\opencv\build\include\opencv2\flann\lsh_table.h	96
Warning	C26495	Variable 'cvflann::lsh::LshStats::bucket_size_std_dev' is uninitialized. Always initialize a member variable (type.6).	OpenCV_Tutorials	C:\Users\nayja\Desktop\OpenCV Projects\opencv\build\include\opencv2\flann\lsh_table.h	96
Warning	C26495	Variable 'cvflann::lsh::LshStats::n_buckets_' is uninitialized. Always initialize a member variable (type.6).	OpenCV_Tutorials	C:\Users\nayja\Desktop\OpenCV Projects\opencv\build\include\opencv2\flann\lsh_table.h	96
Warning	C26495	Variable 'cvflann::UntypedMatrix::type' is uninitialized. Always initialize a member variable (type.6).	OpenCV_Tutorials	C:\Users\nayja\Desktop\OpenCV Projects\opencv\build\include\opencv2\flann\matrix.h	97
Warning	C26495	Variable 'cv::detail::RotationWarperBase<cv::detail::CompressedRectilinearPortraitProjector>::projector_' is uninitialized. Always initialize a member variable (type.6).	OpenCV_Tutorials	C:\Users\nayja\Desktop\OpenCV Projects\opencv\build\include\opencv2\stitching\detail\warpers.hpp	169
Warning	C26495	Variable 'cv::detail::RotationWarperBase<cv::detail::CompressedRectilinearProjector>::projector_' is uninitialized. Always initialize a member variable (type.6).	OpenCV_Tutorials	C:\Users\nayja\Desktop\OpenCV Projects\opencv\build\include\opencv2\stitching\detail\warpers.hpp	169
Warning	C26495	Variable 'cv::detail::RotationWarperBase<cv::detail::PaniniPortraitProjector>::projector_' is uninitialized. Always initialize a member variable (type.6).	OpenCV_Tutorials	C:\Users\nayja\Desktop\OpenCV Projects\opencv\build\include\opencv2\stitching\detail\warpers.hpp	169
Warning	C26495	Variable 'cv::detail::RotationWarperBase<cv::detail::PaniniProjector>::projector_' is uninitialized. Always initialize a member variable (type.6).	OpenCV_Tutorials	C:\Users\nayja\Desktop\OpenCV Projects\opencv\build\include\opencv2\stitching\detail\warpers.hpp	169
Warning	C26451	Arithmetic overflow: Using operator '+' on a 4 byte value and then casting the result to a 8 byte value. Cast the value to the wider type before calling operator '+' to avoid overflow (io.2).	OpenCV_Tutorials	C:\Users\nayja\Desktop\OpenCV Projects\opencv\build\include\opencv2\core\cuda.inl.hpp	301
Warning	C26451	Arithmetic overflow: Using operator '<<' on a 4 byte value and then casting the result to a 8 byte value. Cast the value to the wider type before calling operator '<<' to avoid overflow (io.2).	OpenCV_Tutorials	C:\Users\nayja\Desktop\OpenCV Projects\opencv\build\include\opencv2\core\cuda.inl.hpp	301
Warning	C26451	Arithmetic overflow: Using operator '+' on a 4 byte value and then casting the result to a 8 byte value. Cast the value to the wider type before calling operator '+' to avoid overflow (io.2).	OpenCV_Tutorials	C:\Users\nayja\Desktop\OpenCV Projects\opencv\build\include\opencv2\core\cuda.inl.hpp	482
Warning	C26451	Arithmetic overflow: Using operator '<<' on a 4 byte value and then casting the result to a 8 byte value. Cast the value to the wider type before calling operator '<<' to avoid overflow (io.2).	OpenCV_Tutorials	C:\Users\nayja\Desktop\OpenCV Projects\opencv\build\include\opencv2\core\cuda.inl.hpp	482
Warning	C26451	Arithmetic overflow: Using operator '+' on a 4 byte value and then casting the result to a 8 byte value. Cast the value to the wider type before calling operator '+' to avoid overflow (io.2).	OpenCV_Tutorials	C:\Users\nayja\Desktop\OpenCV Projects\opencv\build\include\opencv2\core\mat.inl.hpp	581
Warning	C26451	Arithmetic overflow: Using operator '<<' on a 4 byte value and then casting the result to a 8 byte value. Cast the value to the wider type before calling operator '<<' to avoid overflow (io.2).	OpenCV_Tutorials	C:\Users\nayja\Desktop\OpenCV Projects\opencv\build\include\opencv2\core\mat.inl.hpp	581
Warning	C26451	Arithmetic overflow: Using operator '+' on a 4 byte value and then casting the result to a 8 byte value. Cast the value to the wider type before calling operator '+' to avoid overflow (io.2).	OpenCV_Tutorials	C:\Users\nayja\Desktop\OpenCV Projects\opencv\build\include\opencv2\core\mat.inl.hpp	610
Warning	C26451	Arithmetic overflow: Using operator '<<' on a 4 byte value and then casting the result to a 8 byte value. Cast the value to the wider type before calling operator '<<' to avoid overflow (io.2).	OpenCV_Tutorials	C:\Users\nayja\Desktop\OpenCV Projects\opencv\build\include\opencv2\core\mat.inl.hpp	610
Warning	C26451	Arithmetic overflow: Using operator '+' on a 4 byte value and then casting the result to a 8 byte value. Cast the value to the wider type before calling operator '+' to avoid overflow (io.2).	OpenCV_Tutorials	C:\Users\nayja\Desktop\OpenCV Projects\opencv\build\include\opencv2\core\mat.inl.hpp	2245
Warning	C26451	Arithmetic overflow: Using operator '<<' on a 4 byte value and then casting the result to a 8 byte value. Cast the value to the wider type before calling operator '<<' to avoid overflow (io.2).	OpenCV_Tutorials	C:\Users\nayja\Desktop\OpenCV Projects\opencv\build\include\opencv2\core\mat.inl.hpp	2245
Warning	C26451	Arithmetic overflow: Using operator '+' on a 4 byte value and then casting the result to a 8 byte value. Cast the value to the wider type before calling operator '+' to avoid overflow (io.2).	OpenCV_Tutorials	C:\Users\nayja\Desktop\OpenCV Projects\opencv\build\include\opencv2\core\utility.hpp	575
Warning	C26451	Arithmetic overflow: Using operator '<<' on a 4 byte value and then casting the result to a 8 byte value. Cast the value to the wider type before calling operator '<<' to avoid overflow (io.2).	OpenCV_Tutorials	C:\Users\nayja\Desktop\OpenCV Projects\opencv\build\include\opencv2\core\utility.hpp	575
Warning	C26451	Arithmetic overflow: Using operator '*' on a 4 byte value and then casting the result to a 8 byte value. Cast the value to the wider type before calling operator '*' to avoid overflow (io.2).	OpenCV_Tutorials	C:\Users\nayja\Desktop\OpenCV Projects\opencv\build\include\opencv2\flann\lsh_table.h	359
Warning	C26451	Arithmetic overflow: Using operator '*' on a 4 byte value and then casting the result to a 8 byte value. Cast the value to the wider type before calling operator '*' to avoid overflow (io.2).	OpenCV_Tutorials	C:\Users\nayja\Desktop\OpenCV Projects\opencv\build\include\opencv2\flann\lsh_table.h	360
Warning	C26451	Arithmetic overflow: Using operator '+' on a 4 byte value and then casting the result to a 8 byte value. Cast the value to the wider type before calling operator '+' to avoid overflow (io.2).	OpenCV_Tutorials	C:\Users\nayja\Desktop\OpenCV Projects\opencv\build\include\opencv2\imgproc.hpp	4908
Warning	C26451	Arithmetic overflow: Using operator '*' on a 4 byte value and then casting the result to a 8 byte value. Cast the value to the wider type before calling operator '*' to avoid overflow (io.2).	OpenCV_Tutorials	C:\Users\nayja\Desktop\OpenCV Projects\opencv\build\include\opencv2\imgproc.hpp	4925
Warning	C26451	Arithmetic overflow: Using operator '+' on a 4 byte value and then casting the result to a 8 byte value. Cast the value to the wider type before calling operator '+' to avoid overflow (io.2).	OpenCV_Tutorials	C:\Users\nayja\Desktop\OpenCV Projects\opencv\build\include\opencv2\objdetect.hpp	127
Warning	C26439	This kind of function may not throw. Declare it 'noexcept' (f.6).	OpenCV_Tutorials	C:\Users\nayja\Desktop\OpenCV Projects\opencv\build\include\opencv2\core\async.hpp	73
Warning	C26439	This kind of function may not throw. Declare it 'noexcept' (f.6).	OpenCV_Tutorials	C:\Users\nayja\Desktop\OpenCV Projects\opencv\build\include\opencv2\core\mat.inl.hpp	1419
Warning	C26439	This kind of function may not throw. Declare it 'noexcept' (f.6).	OpenCV_Tutorials	C:\Users\nayja\Desktop\OpenCV Projects\opencv\build\include\opencv2\core\mat.inl.hpp	1444
Warning	C26439	This kind of function may not throw. Declare it 'noexcept' (f.6).	OpenCV_Tutorials	C:\Users\nayja\Desktop\OpenCV Projects\opencv\build\include\opencv2\core\mat.inl.hpp	3937
Warning	C26439	This kind of function may not throw. Declare it 'noexcept' (f.6).	OpenCV_Tutorials	C:\Users\nayja\Desktop\OpenCV Projects\opencv\build\include\opencv2\core\mat.inl.hpp	3961
Warning	C26439	This kind of function may not throw. Declare it 'noexcept' (f.6).	OpenCV_Tutorials	C:\Users\nayja\Desktop\OpenCV Projects\opencv\build\include\opencv2\core\ptr.inl.hpp	258