Attributes that are available to the uploader page are configured here (Admin > Attributes > Display Attributes)

Embedded metadata extraction

Note, for any attributes that you want to hide during upload (that you also want metadata extracted for - e.g. File Format or Date Created), you hide this via the Asset Type, rather than on this page.

E.g. visit Admin > Asset Type "Edit"

From here select the attribute you want to hide on upload. 

This ensures the attribute does not appear during upload, but any metadata extractions will still take place that have been configured for this attribute.