I’ve also noticed that is you want a chest smaller than DDD, it’s almost impossible with some models — unless you specify that they are a gymnast.
That’s also another point of present generative AI image weakness — humans have an intuitive understanding of relative terms and can iterate on them.
So, it’s pretty easy for me to point at an image and ask a human artist to “make the character’s breasts larger” or “make the character’s breasts smaller”. A human artist can look at an image, form a mental model of the image, and produce a new image in their head relative to the existing one by using my relative terms “larger” and “smaller”. They can then go create that new image. Humans, with their sophisticated mental model of the world, are good at that.
But we haven’t trained an understanding of relative relationships into diffusion models today, and doing so would probably require a more sophisticated — maybe vastly more sophisticated — type of AI. “Larger” and “smaller” aren’t really usable as things stand today. Because breast size is something that people often want to muck with, people have trained models on a static list of danbooru tags for breast sizes, and models trained on those can use them as inputs, but even then, it’s a relatively-limited capability. And for most other properties of a character or thing, even that’s not available.
For models which support it, prompt term weighting can sometimes provide a very limited analog to this. Instead of saying “make the image less scary”, maybe I “decrease the weight of the token ‘scary’ by 0.1”. But that doesn’t work with all relationships, and the outcome isn’t always fantastic even then.
That’s also another point of present generative AI image weakness — humans have an intuitive understanding of relative terms and can iterate on them.
So, it’s pretty easy for me to point at an image and ask a human artist to “make the character’s breasts larger” or “make the character’s breasts smaller”. A human artist can look at an image, form a mental model of the image, and produce a new image in their head relative to the existing one by using my relative terms “larger” and “smaller”. They can then go create that new image. Humans, with their sophisticated mental model of the world, are good at that.
But we haven’t trained an understanding of relative relationships into diffusion models today, and doing so would probably require a more sophisticated — maybe vastly more sophisticated — type of AI. “Larger” and “smaller” aren’t really usable as things stand today. Because breast size is something that people often want to muck with, people have trained models on a static list of danbooru tags for breast sizes, and models trained on those can use them as inputs, but even then, it’s a relatively-limited capability. And for most other properties of a character or thing, even that’s not available.
For models which support it, prompt term weighting can sometimes provide a very limited analog to this. Instead of saying “make the image less scary”, maybe I “decrease the weight of the token ‘scary’ by 0.1”. But that doesn’t work with all relationships, and the outcome isn’t always fantastic even then.