Why is there no sharing weights in the prototxt?

[sciencepanda]

Hi, I also get a work to implement the DeepID recently, and I have searched many repositories about Face Verification and DeepID in github. I found none of them shows any features about sharing weights in their model configurations, which, however, is clearly included in 3th and 4th convolution layers of the model in Yi Sun's Deep Learning Face Representation from Predicting 10,000 Classes (http://mmlab.ie.cuhk.edu.hk/pdf/YiSun_CVPR14.pdf). I don't know why this happened. It seems like everyone ignored this characteristic for some conventional reason? Looking forward to your response!