METHOD AND DEVICE FOR TRANSFORMATION OF IMAGE AND METHOD AND DEVICE FOR REVERSE TRANSFORMATION OF IMAGE

摘要

Disclosed are methods and devices for the transformation and the reverse transformation of images. The method for the transformation of images comprises: generating a substituted NxN transformation matrix (where N is an integer) by using values based on N variables to substitute elements constituting an NxN transformation matrix used in the one-dimensional discrete cosine transformation of a block having a size of NxN; obtaining the multiplication-product matrix of the substituted NxN transformation matrix and a transpose matrix of the substituted NxN transformation matrix; and obtaining the N variables arranged to minimise the sum of the squares of the elements still present after excluding the diagonal component of the multiplication-product matrix obtained in the way described above; and transforming the block having a size of NxN by using the NxN transformation matrix substituted with the values based on.the N variables obtained.