He asked for the “blackbox that takes set of images as an input and produces a 3D model as an output.”
That black box is Object Capture API, which takes a folder of images and outputs an USDZ (or OBJ) file. Model I/O isn’t necessary.
Kudos to Apple for releasing a photogrammetry pipeline that allows web and app developers to build tools like this, with zero knowledge of 3D reconstruction required.