Regression for angles

[shinysingh]

Currently the cars are broadly classified into 3 angles, -45 degrees, +45 degrees, 0 degrees. It is a classification task and not regression as it should be.

A network for regression needs to be developed that can take an image as input and label the angle from anywhere between -45 to 45 degrees.

All the literature so far does not tell us a nice way to do this. The links related to this issue are as follows:

BVLC/caffe#512
BVLC/caffe#881
BVLC/caffe#1765
https://groups.google.com/forum/#!topic/caffe-users/o4cpDNylo3Q
https://groups.google.com/forum/#!topic/caffe-users/8iE_t-P_m3M
http://corpocrat.com/2015/02/24/facial-keypoints-extraction-using-deep-learning-with-caffe/

@satwikkottur will be using this.