A study on extraction methods for building colors in traditional residential facades: a case study in Shen’ao Village, Zhejiang

In contemporary rural China, many newly built and renovated dwellings suffer from stylistic inconsistency and a loss of regional identity. To address this, architects and scholars increasingly rely on extracting and translating architectural vocabulary, particularly facade color, as a critical design strategy. This study investigates three representative spatial nodes in Shen’ao Village, Zhejiang Province, proposing an efficient method for extracting facade color vocabulary tailored specifically to traditional residential architecture. In addition to conventional manual mapping with color block filling, panoramic photography combined with image analysis, and aerial photogrammetry modeling combined with image analysis were evaluated. Percentage-wise comparisons indicate that aerial modeling provides the highest accuracy, achieving deviations within approximately 3–5% of manual mapping, whereas uncorrected panoramic methods demonstrated deviations exceeding 15%. However, after applying empirically derived correction coefficients and formulas, panoramic synthesis accuracy significantly improved to deviations within approximately 6–8%. The resulting method effectively balances technical feasibility, efficiency, and ease of use, offering architects a practical quantitative tool for color and material translation in heritage conservation and contemporary vernacular design contexts.