Soft Shadow Rendering based on Real Light Source Estimation in Augmented Reality

The most challenging task in developing Augmented Reality (AR) applications is to make virtual objects mixed harmoniously with the real scene. To achieve photorealistic AR environment, three key issues must be emphasized namely consistency of geometry, illumination and time. Shadow is an essential element to improve visual perception and realism. Without shadow, virtual objects will appear like it is floating and thus will make the environment look unrealistic. However, many shadow algorithms still have drawbacks such as producing sharp and hard-edged outlines, which make the shadow’s appearance unrealistic. Thus, this paper will focus on generating soft shadow in AR scene, rendered base on real light sources position. The reflective sphere is used to create environment map image that can estimate the light source from the real scene and generate the soft shadows.