Stability AI releases its Image Upscaling API

Today Stability AI announces the release of its Image Upscaling API, an AI-powered tool that increases the size of any image without compromising its sharpness. 

Original 512x512 image on left, Upscaled 4x image on right

The Image Upscaling API is the latest addition to Stability AI’s existing image generation and editing APIs, like the popular text-to-image, image-to-image and inpainting APIs. Upscaling adds to those popular tools by expanding small images into larger ones while maintaining – or even improving – their level of detail.

Why is this awesome?

Since the emergence of digital imagery, it has been nearly impossible to expand small images into larger ones without compromising the quality of the image. Now users can pass a small image into the API and get back one with more than double the level of detail. 

Upscaler Model Details

There are two open source models behind the Image Upscaling API. The first is the super-fast Real-ESRGAN, which can double the resolution of a typical 512x512 image in half a second. The second is the ‘latent’ Stable Diffusion 4x Upscaler which takes between 20 to 40 seconds to enlarge an image but provides more detailed results with a richer texture. 

Both models can be used to upscale any images, whether they were generated using the Stability API or not. A key advantage of the latent Stable Diffusion 4x Upscaler is its advanced diffusion process that increases the perceived level of detail while upscaling the input image.

Introducing these models aligns with our vision to continuously enrich the Image Upscaling API with state-of-the-art models as they become available.

Get Started

To start with the Image Upscaling API, check out its documentation here. If you’re a user of Stability for Photoshop or Stability for Blender, we’ve integrated the API into the latest versions of those add-ons as well.