NOTE

References:
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[1] P. Felzenszwalb, R. Girshick, D. McAllester, D. Ramanan. "Object Detection with Discriminatively Trained Part Based Models." IEEE Transactions on Pattern Analysis and Machine Intelligence, Vol. 32, No. 9, September 2010.
[2] P. Felzenszwalb, etc "Cascade Object Detection with Deformable Part Models"
URL: http://people.cs.uchicago.edu/~pff/latent/