GIMP Stable Boy: Avoid Adobe and create magic for free 💥🚀

You don't need to spend money on a Creative Cloud subscription to enjoy Photoshop's Firefly features. I'll show you how to create a free and powerful solution, accessible even on a modest PC, since it runs in the cloud.

Photoshop Firefly: Pure Magic, But Expensive 💸

Photoshop's generative fill feature is incredibly powerful. If you've ever spent hours compositing images, seeing an object instantly appear, perfectly integrated into perspective and lighting, is striking. You simply paint a selection, type what you want (a cat, a ball, a tree), and Photoshop automatically generates it.

Adobe Photoshop with IAS fill; however, this feature is locked behind a Creative Cloud subscription, which costs $20 per month just to use it.

GIMP + Stable Boy: A Free and Open Source Alternative 🆓

Looking for open-source alternatives, it seemed impossible to find a generative fill as advanced as Photoshop Firefly. But I discovered Stable Boy, a free plugin for GIMP based on Stable Diffusion, a powerful AI image generation model.

Stable Boy allows you to paint areas with masks and use text to describe what to generate; it also supports remixing and enhancing images, emulating the Adobe Firefly experience.

To use it locally, you need a powerful GPU, but if you're using a regular PC, you can take advantage of the cloud. Google Colab allows you to run AI models for free and link them to the plugin via API, facilitating universal access.

What You Need to Make It Work ✅

These are the necessary elements:

• GIMP: Free image editor compatible with plugins.
• Plugin Stable Boy para GIMP.
• Google Colab to run Stable Diffusion and generate an API URL.
• Access to Google Drive for Google Colab.
• A little bit of DIY spirit and patience.

1. Download GIMP version 2.10.34 (stable and compatible with Stable Boy).
2. Download Stable Boy from GitHub.
3. Access to a Google account and Google Colab.
4. Stable Diffusion Notebook on Google Collab.
5. The URL of the API that generates the notebook.

Step 1: Install GIMP and Load Stable Boy

Download the version Download GIMP version 2.10.34 from the official link. Installation is quick and easy; use the offline installer for added security.

To get Stable Boy you have two options: with Git installed, open terminal and run:

git clone https://github.com/thndrbrrr/gimp-stable-boy.git

If you don't have Git, download the ZIP file from the GitHub page and extract the folder.

In GIMP, go to Edit > Preferences. Expand Folders at the bottom and select Plug-insHere we will add the Stable Boy route.

Open the Stable Boy folder and copy the full folder path src, For example:

C:\Users\Usuario\gimp-stable-boy\src

Paste this path into the Preferences window where you add a new folder. Restart GIMP and you should see the Stable Boy button in the top bar.

Step 2: Activate Stable Boy with the AI ​​Model 🚀

The key part now is to get the AI ​​backend up and running. To do this, we opened the Google Colab notebook which runs Stable Diffusion and generates the API that GIMP needs.

Run all the cells using the play button. Some will request permission to access Google Drive; accept to continue. When running the model cell, select “v1.5 Inpainting” to ensure a high-quality, distortion-free generative fill.

Finally, when you run the cell to start Stable Diffusion, a public URL will be generated that functions as an API for Stable Boy. Don't close this tab while you're working!

Next, return to GIMP, open any image, or create a new document. In the Stable Boy menu, select "Preferences" and enter the API URL without the trailing slash to avoid errors.

Let's Test Our Settings ⚙️

With an active document, create a new transparent layer called Inpainting Mask (Respect capitalization and exact spacing). This will be the layer for painting the fill mask.

Use a black brush to paint the outline of the object you want to create, such as a ball, onto the layer. Greater precision yields better results.

Make sure you have the “Inpainting Mask” layer selected. Then, in the Stable Boy menu, choose “Inpainting”.

Enter a descriptive prompt, for example:

A realistic soccer ball with a soft shadow underneath

Press OK and wait a few seconds. The generated image will appear on a new layer, which you can hide or delete as you prefer.

Another example with prompt:

A realistic golden retriever puppy sitting on the grass, front view

Tips for Solving Common Problems 🔧

If you notice strange cropping or blurry images, consider these possible errors:

1. Stable Boy or the Stable Diffusion version are not configured correctly.
2. The Inpainting Mask layer was not properly named or created.
3. It requires modifying plugin settings to improve results.

Try other Stable Boy features (such as upscaling or text-to-image) to validate whether the problem is with the model or the plugin.

To verify the model, open the API URL in your browser; it should display “sd-v1-5-inpainting.ckpt” in the upper right corner. If not, change the model in the notebook and run it again.

To verify that Python works in GIMP, go to Filters > Python-fu > ConsoleIf the console does not appear, reinstall GIMP 2.10.34, which includes native support for Python.

Check that the “Inpainting Mask” layer is correctly named, painted with a black brush at 100% opacity, and selected for the generation to work properly.

I recommend these adjustments for better results:

• Denoising force between 75%-80%
• Fill mode: Latent Noise
• Number of steps: approximately 40
• Sampler: DPM++ 2M Karras (if available)

The results I got with this DIY generative engine were amazing. The setup can be a bit challenging, but the experience is incredibly rewarding and fun. Give it a try and share your creations! 🚀🎨