Upscayl

Real-ESRGAN

Tencent ARC|N/A

Real-ESRGAN is an open-source image upscaling and restoration model developed by Xintao Wang and collaborators at Tencent ARC Lab that enhances low-resolution, degraded, or compressed images to high-resolution outputs with remarkable detail recovery. Released in 2021 under the BSD license, Real-ESRGAN builds on the original ESRGAN architecture by introducing a high-order degradation modeling approach that simulates the complex, unpredictable quality loss found in real-world images, including compression artifacts, noise, blur, and downsampling. The model uses a U-Net architecture with Residual-in-Residual Dense Blocks as its generator network, trained with a combination of perceptual loss, GAN loss, and pixel loss to produce sharp, natural-looking upscaled results. Real-ESRGAN supports upscaling factors of 2x, 4x, and higher, and includes specialized model variants for anime and illustration content alongside the general-purpose photographic model. The model handles real-world degradations far better than its predecessor ESRGAN, which was trained only on synthetic degradation patterns. Real-ESRGAN has become one of the most widely deployed AI upscaling solutions, integrated into numerous applications including desktop tools, web services, mobile apps, and professional image editing workflows. The model runs efficiently on both CPU and GPU, with the lighter RealESRGAN-x4plus-anime variant optimized for consumer hardware. As a fully open-source project available on GitHub with pre-trained weights, it serves as the backbone for popular tools like Upscayl and various ComfyUI nodes. Real-ESRGAN is essential for photographers, content creators, game developers, and anyone who needs to enhance image resolution while preserving natural appearance and adding realistic detail.

Topaz Gigapixel AI

Topaz Labs|N/A

Topaz Gigapixel AI is a commercial desktop application for AI-powered image upscaling and enhancement developed by Topaz Labs, positioned as an industry-standard tool for professional photographers, graphic designers, and image processing specialists. Available on Windows and macOS, the software uses a proprietary hybrid neural network architecture that combines multiple AI models to upscale images by up to 600 percent while preserving and even enhancing fine details, textures, and sharpness. Topaz Gigapixel AI includes specialized processing modes for different content types including faces, standard photography, computer graphics, and low-resolution sources, with each mode optimized to produce the best possible results for its target content. The software features intelligent face detection and enhancement that improves facial details during upscaling, producing natural-looking results even from very low-resolution source images. Topaz Gigapixel AI supports batch processing for handling large volumes of images and integrates with Adobe Lightroom and Photoshop as a plugin, fitting seamlessly into professional photography workflows. The application processes images locally on the user's machine using GPU acceleration, ensuring privacy and fast processing without requiring an internet connection. Output quality is widely regarded as among the best available in commercial upscaling software, with particular strength in preserving natural textures and avoiding the artificial smoothing common in many AI upscalers. As a proprietary product with a one-time purchase or subscription model, Topaz Gigapixel AI is particularly valued by professional photographers enlarging prints, real estate photographers enhancing property images, forensic analysts improving evidence imagery, and archivists restoring historical photographs to modern resolution standards.

CodeFormer

Tencent ARC|N/A

CodeFormer is a state-of-the-art blind face restoration model developed by researchers at Nanyang Technological University in collaboration with Tencent ARC, presented at NeurIPS 2022. The model employs a unique Transformer-based architecture with a discrete codebook lookup mechanism to restore severely degraded facial images with exceptional fidelity. Its most distinguishing feature is an adjustable w parameter ranging from 0.0 to 1.0 that gives users precise control over the balance between identity preservation and restoration quality. Architecturally, CodeFormer consists of three core components: a VQGAN encoder-decoder that learns discrete visual codes from high-quality face datasets, a codebook that stores these learned representations, and a Transformer module that predicts optimal code combinations during restoration. This approach enables the model to produce plausible facial details even under extreme degradation because it draws information from learned priors rather than solely from the corrupted input. In benchmark evaluations on CelebA-HQ and WIDER-Face datasets, CodeFormer achieves superior results across FID, NIQE, and identity similarity metrics compared to previous methods. Practical applications include restoring old family photographs, enhancing faces in AI-generated images, extracting facial details from low-resolution video frames, and professional photo retouching. The model is open source, integrates with popular tools like ComfyUI, AUTOMATIC1111 WebUI, and Fooocus, and offers cloud inference through Replicate API and Hugging Face Spaces demos for accessible experimentation.

SUPIR

Tencent ARC|N/A

SUPIR is an advanced AI image restoration and upscaling model developed by Tencent ARC researchers in 2024 that harnesses the generative power of SDXL, a large-scale Stable Diffusion model, for photo-realistic image enhancement. SUPIR stands for Scaling Up to Excellence: Practicing Model Scaling for Photo-Realistic Image Restoration in the Wild. The model introduces a degradation-aware encoder that analyzes the specific types of quality loss present in an input image and generates intelligent text prompts to guide the restoration process, effectively telling the diffusion model what kind of content needs to be restored and how. This intelligent prompting approach enables SUPIR to produce remarkably detailed and natural-looking upscaled results that go beyond simple pixel interpolation to generate semantically meaningful detail. The model leverages the vast visual knowledge embedded in SDXL's pre-trained weights to synthesize realistic textures, facial features, text, and fine patterns during upscaling. SUPIR excels particularly at restoring severely degraded images where traditional upscaling methods fail, including old photographs, heavily compressed web images, and low-resolution captures. The model supports high upscaling factors while maintaining coherent content and natural appearance. Released under a research-only license, SUPIR is open source with code and weights available on GitHub. While computationally intensive due to its SDXL backbone, the model produces results that represent the current frontier of AI-powered image restoration quality. SUPIR is particularly valuable for professional photographers restoring archival images, forensic analysts enhancing surveillance footage, and digital artists who need maximum quality from limited source material.