%X Formalized in ISO 12913, the “soundscape†approach is a paradigmatic shift towards perceptionbased urban sound management, aiming to alleviate the substantial socioeconomic costs of noise pollution to advance the United Nations Sustainable Development Goals. Focusing on traffic-exposed outdoor residential sites, we implemented an automatic masker selection system (AMSS) utilizing natural sounds to mask (or augment) traffic soundscapes. We employed a pre-trained AI model to automatically select the optimal masker and adjust its playback level, adapting to changes over time in the ambient environment to maximize “Pleasantnessâ€, a perceptual dimension of soundscape quality in ISO 12913. Our validation study involving (í‘ = 68) residents revealed a significant 14.6 % enhancement in “Pleasantness†after intervention, correlating with increased restorativeness and positive affect. Perceptual enhancements at the traffic-exposed site matched those at a quieter control site with 6 dB(A) lower í¿A,eq and road traffic noise dominance, affirming the efficacy of AMSS as a soundscape intervention, while streamlining the labour-intensive assessment of “Pleasantness†with probabilistic AI prediction. %K Urban soundscape, natural sounds, auditory masking, probabilistic approach, soundscape augmentation, artificial intelligence %V 266 %A Bhan Lam %A Zhen-Ting Ong %A Kenneth Ooi %A Wen-Hui Ong %A Trevor Wong %A Karn N Watcharasupat %A Vanessa Boey %A Irene Lee %A Joo Young Hong %A Jian Kang %A Kar Fye Alvin Lee %A Georgios Christopoulos %A Woon-Seng Gan %J Building and Environment %I Elsevier BV %L discovery10198304 %D 2024 %O This version is the author accepted manuscript. For information on re-use, please refer to the publisher’s terms and conditions. %T Automating urban soundscape enhancements with AI: In-situ assessment of quality and restorativeness in traffic-exposed residential areas