Property of Sub-affine Transformation and Its Application

Scrambling is the basic means for hiding huge image information.A subset of affine transformation with integer coefficients and invariance of image area is introduced to realize the scrambling of digital image.Necessary conditions and properties of sub-affine transformation are given.The periodicity of sub-affine transformation of digital images is discussed.Experimental results show that sub-affine transformation scrambling is superior to Arnold transformation,Fibonacci transformation and geometric transformation.