What does the parameter "nstripes" mean in paralell_for_() function in OpenCV3? From my initial search, I found the following points.
1. "Specifying proper nstripes can be crucial for good performance" says the OpenCV3 presentation in CVPR 2015.
2. Browsing the source files, I found that this parameter is passed to the underlying pthreads wrapper.
3. Most importantly, this parameter cannot exceed the size of the first parameter Range passed to parallel_for_
4. In bgfg_gaussmix2.cpp, the parallel_for_ is invoked with nstripes parameter equal to "image.total()/(double)(1 << 16)", that is, the total number of pixels divided by 256*256. Why is this so?
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