Medical Image Overlay Rendering with Differentiable Alignment

The patent pre-computes and stores light transport properties (such as scattering coefficients, absorption coefficients, and phase functions) in lookup tables before the actual rendering process. During real-time rendering, these pre-computed values are retrieved and applied directly, avoiding the need to perform complex Monte Carlo simulations on-the-fly. This preliminary preparation step enables photorealistic rendering quality while maintaining real-time performance.

The patent segments the rendering process into two distinct parts: a pre-computation phase where complex light transport properties are calculated and stored, and a real-time rendering phase where these pre-computed properties are applied using efficient ray casting. This segmentation allows the system to achieve both photorealistic quality (through the detailed pre-computed light transport models) and computational speed (through efficient real-time ray casting with pre-prepared data).

The patent performs differentiable rendering and optimization of rendering parameters (such as lighting, shading, and material properties) during a pre-processing stage before final rendering. By completing the computationally intensive differentiable optimization beforehand, the system achieves high alignment precision and photorealistic quality while keeping the real-time rendering system relatively simple and memory-efficient.