They are called similarity digests or sometimes "fuzzyhashing". For generic files there are Context Triggered Piecewise Hashing (CTPH), Trend Micro Locality Sen

They are called similarity digests or sometimes "fuzzyhashing". For generic files there are Context Triggered Piecewise Hashing (CTPH), Trend Micro Locality Sensitive Hash (TLSH) and Similary Digest Hash (SDHash)