Image Processing for Public Health Surveillance of Tobacco Point-of-Sale Advertising: Machine Learning-Based Methodology. - English, Ned; Anesetti-Rothermel, Andrew; Zhao, Chang; Latterner, Andrew; Benson, Adam F; Herman, Peter; Emery, Sherry; Schneider, Jordan; Rose, Shyanika W; Patel, Minal; Schillo, Barbara A (Journal of Medical Internet Research, 2021)