Set of additional test images :
airplaneU2.bmp or airplaneU2.pgm : grey 1024x1024
cablecar.bmp or cablecar.ppm : color 512x480
cornfield.bmp or cornfield.ppm : color 512x480
flower.bmp or flower.ppm : color 512x480
flowers.bmp or flowers.ppm : color 500x362
fruits.bmp or fruits.ppm : color 512x480
girl.bmp or girl.ppm : color 720x576
houses.bmp or houses.pgm : grey 512x512
kiel.bmp or kiel.pgm : grey 512x512
lighthouse.bmp or lighthouse.pgm : grey 512x512
monarch.bmp or monarch.ppm : color 768x512
pens.bmp or pens.ppm : color 512x480
soccer.bmp or soccer.ppm : color 512x480
tiffany.bmp or tiffany.ppm : color 512x512
