Color-aware perceptual hashing

[Dorumin]

Has there been any research into color aware hashes? From what I can see in this crate every implemented HashAlg grayscales the image as a first step, most likely to pack each hash "pixel" as a single byte. Adding color profile settings like ColorProfile::{Grayscale, RGB, RGBA} might multiply the size of the hash by the channel count, and there's probably no way of avoiding that as far as I'm aware without sacrificing color depth or detail.

In any case, would it be possible to implement this into the library?