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##### System information (version)
<!-- Example
- OpenCV => 3.1
- Operating System / Platform => Windows 64 Bit
- Compiler => Visual Studio 2015
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- OpenCV => :grey_question:
- Operating System / Platform => :grey_question:
- Compiler => :grey_question:
##### Detailed description
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##### Steps to reproduce
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```.cpp
// C++ code example
```
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