This paper reviews several theoretical frameworks of visual analysis used in computer-based Visual Impact Assessment (VIA) for design decisions in architecture, urban landscape and urban planning. The discussion will focus on the underlying issues of preferences and predictions between designer and lay-public, methodologies of visual analysis, and computing media technologies due to fact that these components primarily contribute towards the result of VIA. Two different sets of visual analysis (i.e. designeris and laymanis points of view) are presented based on Sanoffis (1991) arguments that lay-public preferences are always become a second opinion compared to the judgments by designers. These theories will then be developed and used in the VIA experiments to understand the impact of the visuals in different media for viewersi understanding. This paper concludes with a discussion and suggestion of analysis framework to be used for the visual experiments.