The art of 3D scanning has become readily available to virtually anyone, through photogrammetry applications, in both desktop and mobile form. If you want to use the scanned meshes further in a project, you will probably need to put in a bunch more work.

how to import and clean a mesh coming from 3D created by pictures like 123Dcatch

Typically scanned meshes are pretty dense for most uses, and if they are being animated, especially deformed, you will need to reconsider how they are put together. Here, 3D Artist Benjamin Vurlod walk through using Blender’s modeling tools to clean up a scanned mesh that was created by 123D catch. Where the scanned data came from is less important here, as you can follow along with meshes from any photogrammetry app.

Ben shows how to import the model, and decimate it down to a usable form. Adding a UVW map to the model for the texture is the last step, giving you one low polygon object and one material.