Poisson Blending vs Copy–Paste: Why Solving a PDE Eliminates Seams

The motivating question If you’ve ever tried to copy an object from one photo into another, you’ve seen the problem immediately: seams . Even with careful masking, edge feathering, and opacity tweaks, the composite still tends to look “pasted.” Our eyes are incredibly sensitive to discontinuities in edges and lighting , not just raw color differences. So here’s the driving question: Why does…