Hi, according to the document, the Custom Vision service uses machine learning algorithms (I assume deep learning) to analyze images. Further details aren't available publicly and I haven't found any white paper regarding the service. However, I'm following up internally with the team, and will provide more details if available. Thanks!
Updates: Custom Vision uses different deep learning models in the system optimized for different purposes such as accuracy, training and inference speed, memory cost, etc. Quick training just trains with a few default configs that cost less for training, which is good for POC, i.e., reasonable performance given low cost. Advanced training will utilize the AutoML system in the backend, which gives better training performance, but costs more training time.