https://github.com/arvindrvs/nsfw_face
https://github.com/rahiel/open_nsfw--
https://github.com/EugenCepoi/nsfw_api
https://github.com/minto5050/NSFW-detection
https://github.com/notAI-tech/NudeNet
https://github.com/yaroslaff/nudecrawler
https://github.com/yahoo/open_nsfw
https://github.com/infinitered/nsfwjs#load-the-model
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https://stackoverflow.com/questions/14396211/how-to-recognise-adult-content-programmatically
https://medium.com/teamruggedio/leveraging-artificial-intelligence-to-detect-and-filter-inappropriate-image-on-uploads-with-55c40cbbbabd
https://medium.com/@morozovsk/computer-vision-and-machine-learning-in-php-using-the-opencv-library-3131fe9df94b
https://cloud.google.com/vision/pricing/?hl=it