Monitoring the Design Layer of Ethnic Commercial Signage with Street-View Imagery and Zero-Shot Vision–Language Classification: A Longitudinal Proof-of-Concept from Wongok-Dong, Ansan

Script-based linguistic-landscape monitoring records which languages appear on shop signs but not the design register in which they are rendered, so a business that keeps minority-language text while adopting mainstream or visitor-oriented visual conventions looks unchanged. We present a methodological proof-of-concept that treats signage design style as a geospatial monitoring object, using annual Kakao Road View cross-sections (2010–2024) of Wongok-dong, Ansan, Korea’s only Multicultural Village Special Zone. The pipeline combines YOLOv8 sign-panel detection, zero-shot CLIP ViT-L/14 classification into five design-style categories, post-stratified spatial weighting, crisis adjustment for closure signage, propagation of sampling and misclassification uncertainty, and spatial analysis (local spatial association and zone-boundary sensitivity). Raw style shares overstate pandemic-period contraction: the 2019–2021 decline in the weighted ethnic vernacular share is 14.4 percentage points on the raw metric but 10.8 points among operating premises. In the periphery, vernacular design gave way mainly to mainstream design; a shift toward visitor-oriented staged design in the commercial core is consistent in direction but rests on few panels and lies within sampling uncertainty. Design and script series diverge after 2019, showing what text-only monitoring misses. All associations are descriptive, and indicator thresholds for planning require validation across multiple enclaves.