Repository: opencv
Issue: convertTo, cv::findContours slower on Window10 (compare with Ubuntu)
Labels: incomplete

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##### System information (version)
<!-- Example
- OpenCV => 4.6.0
- Operating System / Platform => Windows 64 Bit
- Compiler => Visual Studio 2019
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- OpenCV => :grey_question:
- Operating System / Platform => :grey_question:
- Compiler => :grey_question:

##### Detailed description

<!-- Hello! After doing the measurements I noticed the functions run slower on window
Linux: convertTo: 197ms, cv::findContours: 167ms
Window10: convertTo: 3245ms, cv::findContours: 747ms
I don't understand why this situation happens despite setting the same Cmake flags. -->

##### Steps to reproduce

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    // C++ code example
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