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hollance / YOLO-CoreML-MPSNNGraph

Tiny YOLO for iOS implemented using CoreML but also using the new MPS graph API.
MIT License
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Understanding the computation with anchor boxes #37

Closed chinmay5 closed 6 years ago

chinmay5 commented 6 years ago

Hi, I am not able to understand how the computation for the bounding boxes along with the anchors are happening. let w = exp(tw) * anchors[2*b ] * blockSize let h = exp(th) * anchors[2*b + 1] * blockSize Helper.swift

  1. How were these anchor boxes selected ?
  2. What was the reason to multiply with the exponential function before scaling with the anchor box value? The second part is what I am more intrigued by. Any help would be highly appreciated.
hollance commented 6 years ago

I'm actually putting the finishing touches on a blog post that explains all this. :-)

chinmay5 commented 6 years ago

Please post the link here as well once you are done :)

hollance commented 6 years ago

All right, here it is: http://machinethink.net/blog/object-detection/