Maximum entropy method with regularization term to suppress spurious spikes in resultant spectral functions. Overfitting problem is sort of solved by this method.
See the link below for a detailed program documentation (in Chinese):
https://zhuanlan.zhihu.com/p/24759384
An English version of the program documentation is now available here:
https://github.com/PrimerLi/maximum-entropy-method/blob/master/algorithm.pdf
A formal presentation of this algorithm can be found here: