The scientific objective of the ISA project is to study the problems of analysis and synthesis of images raised by applications of virtual reality and augmented reality. In the particular application domain constituted by architectural and urban environments, we want to propose original methods to make techniques from computer vision and visualization cooperate, in computer aided design, implementation simulation, and mission preparation systems. These methods find their roots in the framework of research conducted in specific fields of artificial vision and visualization, but also in their integration in real size experimentations.