I'm sure the comment you're replying to wasn't thinking of the algorithm that applies a filter to a jpeg, but the process by which that filter is created in the first place. The assumption being that there's some sort of theory to colour that allows you to systematically improve the aesthetic qualities of images.
The creative process isn't novel. There isn't even the capability of any layer masking in most mobile apps, including Instagram, compared to pre-existing more robust tools on desktop (and other mobile apps), severely limiting the 'technical interestingness' to begin with.
As an analogy, think of the value music theory (i. e. https://en.wikipedia.org/wiki/Scale_(music)#Harmonic_content) for composition.