Deduction: If Ternary color equal, the image: BLACK, WHITE, GREY.

What's the smallest color image NFT? It's one pixel color image. Let's try, Conditions:

1. a color NFT:RGB (Red+Green+Blue)
2. one pixel NFT
3. All color equal: Red Val = Green Val = Blue Val
4. Range of (Red Val , Green Val , Blue Val) : (0,0,0)~(255,255,255)

Result: 256 unique one-pixel NFT. (image format :PNG, avg image size = 70 bytes).

Deduction: If Ternary color equal, the image: BLACK, WHITE, GREY.