Local Image Generation: Create AI Images on Your Own PC

Published by LLMnet Editorial Team | Category: AI Guides

The rise of tools like Midjourney, DALL-E 3, and Adobe Firefly has made image generation accessible to the general public. However, these services run in the cloud, meaning you are dependent on subscriptions, internet connections, and strict censorship filters. In recent years, a powerful alternative has emerged: local image generation. By running open-source models like Stable Diffusion and FLUX on your own computer, you regain full control.

In this comprehensive guide, we discuss what is needed to generate professional AI images locally yourself. We look at the hardware requirements, the various available models, the most user-friendly software, and the complex but fascinating learning curve of prompts and model settings.

Why Generate Images Locally?

Setting up a local environment takes time and requires an investment in hardware, but the benefits are decisive for many hobbyists and professionals:

  • Full control and flexibility: Where cloud services often give you a simple text bar, local tools offer access to advanced techniques such as ControlNet (which allows you to determine the exact pose of a character) and Inpainting (locally modifying specific parts of an image, such as a hand or an eye).
  • No subscription fees: Although the hardware is a one-time investment, generating tens of thousands of images is completely free after that. You don't pay per 'credit' or per month.
  • Privacy and trade secrets: For design agencies and companies, uploading reference images to a US cloud server is often a no-go. Local generation ensures a completely privacy-friendly AI workflow where not a single byte leaves your network.
  • Uncensored: Local models have no built-in refusal mechanisms for certain words or concepts, guaranteeing artistic freedom without running into false 'policy violations'.

Hardware Requirements: What Does Your Computer Need?

Image generation is mathematically intensive. While text models (LLMs) mainly depend on fast memory bandwidth, image models rely heavily on the graphics card (GPU). If you want to get serious, a powerful graphics card is essential. We also recommend consulting our broader guide on hardware for local AI, as many principles overlap.

Graphics Card (GPU) and VRAM

The absolute bottleneck for local image generation is VRAM (Video RAM). This is the memory of your graphics card. If a model (including reference images and ControlNet layers) does not fit in the VRAM, your PC has to fall back on regular system memory (RAM), which slows down the generation process from seconds to minutes or even hours.

  • Minimum (6GB - 8GB VRAM): With 8GB, you can effortlessly run older models like Stable Diffusion 1.5. The newer SDXL also works, albeit with some optimizations and slower generation times.
  • Recommended (12GB - 16GB VRAM): This is the 'sweet spot'. With cards like the NVIDIA RTX 3060 (12GB) or 4070 Ti Super (16GB), you can run complex workflows, larger resolutions, and heavy models without any issues.
  • High-end (24GB VRAM): With an RTX 3090 or 4090, you can generate huge batches of images at once, apply video generation (like AnimateDiff), and run the heaviest new models like FLUX smoothly.

NVIDIA vs. AMD vs. Apple Silicon: By far the most open-source AI tools are built around CUDA, NVIDIA's architecture. NVIDIA is therefore by far the safest choice, offering the fastest performance and easiest installation. AMD cards work via ROCm, but this often requires more technical knowledge and bugs occur more frequently. Apple users with M1/M2/M3 chips (especially the Max and Ultra variants with lots of 'Unified Memory') have a major advantage because system memory and video memory are shared. Software like Draw Things is excellently optimized for Apple Silicon via the Metal framework.

RAM and Storage

In addition to the GPU, you preferably need at least 32GB of regular RAM. A fast NVMe SSD is also crucial. AI models are gigantic files. A single SDXL model easily weighs 6.5 GB. Before you know it, you will have reserved 200 GB to 500 GB of storage space for different styles, models, and tools.

Which Models Are Available?

The strength of the open-source community is that there is not just one model, but thousands. However, they build on a few fundamental architectures. If you are in doubt, check out our guide on choosing a local model for more depth.

Stable Diffusion (SD 1.5 and SDXL)

Released in 2022, Stable Diffusion 1.5 changed the world. The resolution (standard 512x512) is outdated today, but because the model is extremely lightweight and millions of modifications have been made for it, it is still widely used. SDXL (Stable Diffusion XL) became the new standard in 2023. It generates images at 1024x1024, understands your text (prompts) much better, and has fantastic details, provided you have at least 8GB of VRAM.

FLUX.1

In 2024, Black Forest Labs released the FLUX.1 model, which is currently considered the undisputed king locally, comparable to or even better than Midjourney V6. FLUX understands extremely complex prompts and can (unlike previous models) spell text perfectly in images. FLUX comes in heavy variants that actually require 24GB of VRAM, but the community quickly created quantized versions, allowing it to run on cards with 12GB or 16GB as well.

Terminology: Checkpoints and LoRAs

When downloading on platforms like Civitai or Hugging Face, you will come across two terms frequently:

  • Checkpoints (or Base Models): These are the full, large files (2GB - 12GB). A checkpoint contains all the 'knowledge' of the model. Think of a checkpoint specifically trained on photorealism, or on anime styles.
  • LoRAs (Low-Rank Adaptations): These are small files (10MB - 300MB) that you apply like a 'topping' over a checkpoint. For example, you can download a LoRA of a specific car, a piece of clothing, or an art style (like 'watercolor'). By combining a LoRA with a checkpoint, you guide the model very precisely in a certain direction.

Accessible Tools and Software (User Interfaces)

You don't run these models via the command line, but through graphical interfaces (UIs) that run in your web browser. Here are the most popular options:

1. Automatic1111 (A1111)

The 'grandfather' of Stable Diffusion interfaces. It looks like a 90s dashboard full of buttons and sliders. The advantage? It supports every conceivable plug-in, extension, and technique. If there is a new AI breakthrough, this is the first tool to support it. The learning curve is steep, though.

2. ComfyUI

A so-called 'node-based' interface. You build your workflow by literally connecting blocks (nodes) with lines. You load a model in one block, send it to a prompt block, then to the sampler, and finally to the output. This is visually intimidating but incredibly powerful for automation. A huge advantage of ComfyUI is that its memory management is superior; it runs heavy models on weaker graphics cards much more efficiently than A1111.

3. Fooocus

If you don't want the complexity of A1111 or ComfyUI, Fooocus is the best choice. Under the hood, Fooocus runs the heavy technology of SDXL, but the interface is just as minimalist as Midjourney. You type your prompt, press generate, and the program does all the heavy technical calculations (such as optimizing VRAM and choosing samplers) in the background. Perfect for beginners.

4. Draw Things (For Mac)

You can install this application directly from the App Store on your Mac or even your iPad. It is completely offline, free, and extremely well-optimized for Apple hardware.

The Learning Curve: Understanding Prompts and Settings

When you open a generation interface, you see more than just a text box. To create good images locally, you need to understand the key variables.

Note: Text-to-image is rarely perfect on the first try. Think of local generation like photography: you take dozens of photos, adjust the lighting (settings), and ultimately choose the best one to edit further (via Inpainting).
Setting Explanation and Best Practices
Positive Prompt What you do want to see in the image. With local models (especially SD 1.5/SDXL), a list of keywords often works better than full sentences. For example: "portrait of a young woman, cinematic lighting, neon colors, highly detailed, 8k". With newer models like FLUX, natural full sentences actually work better.
Negative Prompt What you absolutely do NOT want to see. This allows you to filter out noise. Commonly used terms are: "ugly, deformed, bad anatomy, blurry, text, watermark".
Steps (Sampling Steps) How many steps the AI takes to work from noise to the image. More steps often mean more detail, but take longer. 20 to 30 steps is optimal for most models. Above 40 steps, you rarely see any improvement.
CFG Scale (Guidance) The Classifier Free Guidance (CFG) determines how strictly the model listens to your prompt. A low value (e.g., 3-4) gives the AI a lot of artistic freedom. A high value (10-15) forces the AI to draw every word in your prompt, but this often results in overexposed and 'fried' images. A safe default is 7.
Sampler The algorithm that removes the noise. Euler a is fast and creative (the image changes slightly with more steps). DPM++ 2M Karras is currently the gold standard for sharp, realistic results and converges quickly.

Practical and Legal Considerations

The freedom of local image generation comes with responsibilities. Locally, you are not bound by ethical filters imposed by companies like OpenAI (DALL-E) or Google.

First of all, there is the copyright aspect. In the European Union (and also outside it), the consensus is that an AI-generated image without human input does not enjoy copyright protection. You do not 'own' the image because a computer made it. However, if you heavily manipulate the output, combine it via ControlNet and Inpainting, and add substantial artistic input, it may still qualify as a new, copyrighted work. You can read more about these legal complexities on our broader knowledge portal on AI and legislation.

Furthermore, the absence of filters raises the risk of deepfakes and NSFW material. Although the tools give you complete technical freedom, you as the user remain fully personally liable and punishable for what you generate and publish under Dutch and European law. Creating non-consensual deepfakes is illegal and ethically reprehensible.

Local vs. Cloud: An Honest Comparison

Let's be honest: if you just need a nice picture quickly for a PowerPoint presentation or a blog, Midjourney or ChatGPT Plus (DALL-E 3) wins in terms of convenience and speed. You type a sentence, and within 15 seconds you have an aesthetically perfect image. A complex local setup with ControlNet nodes and manual VRAM management cannot compete with that in terms of ease of use.

However, local image generation is not meant for people who just want to press a single button. It is meant for creators, artists, developers, and privacy-conscious companies who want to use AI as a digital pencil. Running locally is the difference between buying a microwave meal (Cloud) and growing your own ingredients to cook at a Michelin-star level (Local). The learning curve is steep, the hardware requirements are significant, but the absolute freedom, control, and long-term cost savings make the investment well worth it.