FreeEnhance: Tuning-Free Image Enhancement via Content-Consistent Noising-and-Denoising Process

FreeEnhance is a novel framework that enhances the quality of generated images by selectively adding lighter noise in high-frequency regions to preserve content structures, while adding heavier noise in low-frequency regions to enrich details. It also incorporates three gradient-based regularizers to further improve the visual quality during the denoising process.