The differences between NovelAI and Stable Diffusion are as follows:
- NovelAI is a model that has changed the model architecture and training process of Stable Diffusion to make better use of tag-based prompts. Stable Diffusion uses a model called CLIP to link text and images, but NovelAI has improved CLIP to increase the accuracy of the generated images for the input prompts.
- NovelAI is a model that has changed the aspect ratio of the images to generate more natural compositions. Stable Diffusion crops multiple training images to an aspect ratio of 1:1 at once to optimize GPU efficiency, which can result in some parts of the image being cut off or weird compositions. NovelAI defines the aspect ratio of the images as 512×768 pixels or a maximum dimension size of 1024, which allows it to preserve the wholeness and details of the images.
- NovelAI is a paid subscription service based on SaaS, and the model is not public. Stable Diffusion is an open source model that can be used for free . NovelAI can also be run on your own PC, but you need to use leaked data and tools to do so. Stable Diffusion is intended to be run on your own PC.