This function will validate the tracking quality of an image. That is, will the phone camera be able to recognize and track a given photo. I need this functionality for a macOS application, but ARKit is not available on macOS. Can anyone give me tips on how to replicate this function? In wwdc video apple defines a trackable image as having [distinct features, well textured, good contrast] and a non trackable image as having [repetitive structures, uniform color regions, narrow histogram]. I imagine this will require python/openCV to implement, but i need more information from Apple, like how narrow is too narrow histogram? What metric for well textured? Can i use accelerate or coreImage to calculate image tracking quality?

My app writes files to the users shared Documents directory. I save the files path but this breaks if the user changes the documents name, moves the document to a new location etc. Is there some kind of persistent file id i can use to keep track of these documents? i've been poking aroundFileManager.default.attributesOfItem(atPath: docUrl.path)and i find attributes like FileAttributeKey.systemFileNumber but this number seems to change every time i run the app. There has to be some way to keep track of files other than their path

macOS Photos allows me to tag people that are in my photos. Is there anyway to access these tags via PHAssest or someother mechanism?