Converting a JPG (or any 2D image) into a usable 3D model is one of the most exciting and active areas at the intersection of computer graphics, photogrammetry, and machine learning. Below, we give a comprehensive, practical, and technical walkthrough of every major approach, the strengths & limitations, tools and file formats, capture tips, workflows, postprocessing steps, and further reading — with links to authoritative resources so you can dive deeper.