[CyberDildonics]

Phong is a lighting model.

What you are talking about is barycentric interpolation, which is what this is doing.

There are already image resizing algorithms that use triangulation (and something called DDE - data dependent interpolation) so the answer to your question is yes it is absolutely a valid idea.

[1wd]

"Phong" refers to two distinct but related things: The Phong reflection model (Ambient + Diffuse + Specular) and Phong shading (normal vector interpolation).

https://en.wikipedia.org/wiki/Phong_reflection_model https://en.wikipedia.org/wiki/Phong_shading

[CyberDildonics]

Correct (I over simplified). Neither really applies here because the interpolation is based on barycentric coordinates, which is the Phong part that was probably being referred to.