The names of the images are:
Clegg 814x880x24 (artistic)
Frymire 1118x1105x24 (artistic)
Lena 512x512x24 (natural)
Monarch 768x512x24 (natural)
Peppers 512x512x24 (natural)
Sail 768x512x24 (natural)
Serrano 629x794x24 (artistic)
Tulips 768x512x24 (natural)
Other images from the Waterloo Repertoire are found in GreySet1 and GreySet2 .