SketchDeco is an innovative online tool that can convert black-and-white sketches, masks, and color palettes into realistic color images without requiring users to define text prompts. By combining ControlNet and a staged generation approach, using Stable Diffusion v1.5 and BLIP-2 text prompts, it delivers faithful image generation and user-driven coloration. It is not only fast and requires no training but also compatible with consumer-grade Nvidia RTX 4090 Super GPUs, providing a valuable resource for creative professionals and hobbyists.