importing clutter data (NCLD clutter) into MATLAB

I would like to import the clutter data from USGS (<http://www.mrlc.gov/nlcd11_data.php>) into MATLAB. The name of the link to download data from the above link is "NLCD 2011 Land Cover".

The downloaded folder has two .rrd and .ige files which are significantly larger and I am guessing they are the clutter data. Does any one have any experience with these?