renorm in DecorelationNormalization

[YaoshengFu]

Could you please explain what is renorm doing in the implementation of DecorelationNormalization? Thanks!

[AliaksandrSiarohin]

This is just an extention of https://arxiv.org/abs/1702.03275 for decorelation. In principle it should be useful to stabilise covariance matrix (note that intuitively you need more samples for decorelation, than for batch norm), but in my experiments renorm was not useful.

[YaoshengFu]

Got it, thanks for your explanation!