METHOD AND DEVICE FOR CONVERTING DIGITAL SIGNAL AND METHOD FOR PREPARING TRANSFORMATION MATRIX

摘要

PROBLEM TO BE SOLVED: To reduce the volume of calculation and calculation errors and to attain conversion of high speed and high quality by executing conversion processing such as the conversion of resolution for an input digital signal in an orthogonally transformed area. SOLUTION: An input orthogonal transformation matrix generation part 11 generates an inverted orthogonal transformation matrix Ts(k) <-1> expressing the inverse transformation of orthogonal transformation applied to an input digital signal 15 in an orthogonally transformed area and an output orthogonal transformation matrix generation part 12 generates an orthogonal conversion matrix Td( L) expressing the inverse processing of inverted orthogonal transformation as decoding processing to be applied to an output digital signal in the orthogonally transformed area. A transformed matrix generation part 13 generates a transformation matrix D based on these matrixes Ts(k) <-1> , Td( L) , and a signal conversion part 14 finds out an output digital signal 16 in the area orthogonally transformed by applying the matrix D to the input digital signal 15.