Research On Visual Evaluation Of Street Space Based On Environmental Preference Theory

Street is the skeleton of a city.It not only guarantees the urban traffic function but also carries human commercial activities,and it is an important part of the overall landscape and urban design.With the application of computer vision in spatial planning and the development of street photography technology,the visual evaluation and research of street space has become a new hotspot in the field of urban and rural planning.Guided by the theory of environmental preference,this paper uses the visual attention model in the field of computer image processing as a tool,and combines the content recognition and pairwise comparison method of environmental psychology.It uses scientific and reasonable research methods to put forward the strategy of street space optimization design,and finally applies the theoretical results to the case of street optimization design of Zipeng Road in Hefei.Visual attention is an important mechanism of human visual perception.Human beings can quickly judge interesting information from complex and diverse visual information.From the perspective of bionics,visual attention model simulates the processing of image by calculating visual attention mechanism.This paper attempts to use the visual attention model to calculate the visual saliency of Street Photos,and find the visual attention area of street space.Sixteen influencing factors of street space visual evaluation were obtained by quantitative method.They are street trees,street shrubs,grassland,architectural style,architectural color,building facade material,street shops,building doors and windows,building structures,billboards,trash cans,flower boxes,skylines and visual openness,road condition and road width.They provided analysis for the results of environmental preference evaluation.Combining the method of content recognition and pairwise comparison,this paper evaluates the environmental preference of street space from three aspects:security,aesthetics and overall preference.It is concluded that both safety perception and aesthetic perception of street are significantly related to overall preference,and aesthetic perception is more relevant than those.Then the influence factors calculated by the visual attention model are used to analyze the evaluation results,and the optimization strategies of street space design are obtained from the perspectives of agreeableness,mystery,coherence,complexity and easy identification.Finally,the strategy is applied to the case of optimal design of Zipeng Road Street in Hefei in the form of unified renovation standards and sectional renovation guidelines,so as to let theory guide practice.