Free Image-Based Virtual Space (FIBVS) is a kind of virtual space, which supports free walkthrough by organizing real world images or videos captured by cameras.Compared with traditional geometry-based virtual space, image-based virtual space (IBVS) has some advantages: constructing easily, rendering fast and reality, et al. However, the free degree of IBVS is limited by real images. How to walk freely in IBVS is a key issue of the research of IBVS construction, so this thesis puts moreconcerns on it. To bu...