Additional metrics for a resource.
resource,int(11),
width,int(11),Resource width
height,int(11),Resource height
file_size,bigint(20),File size
resolution,int(11),Resolution - requires $exiftool_resolution_calc
unit,varchar(11),Unit information - requires $exiftool_resolution_calc.
page_count,int(11),Total page count for multi-page previews.