APPARATUS AND METHOD FOR TRANSFORMING BETWEEN DISCRETE COSINE TRANSFORM COEFFICIENT AND COSINE TRANSFORM COEFFICIENT

• Main Authors: LIM, SANG HEE, PAIK, JOON KI
• Format: Patent
• Language: English
• Published: 14.01.2009
• Subjects: ELECTRIC COMMUNICATION TECHNIQUE; ELECTRICITY; PICTORIAL COMMUNICATION, e.g. TELEVISION

A cross transformation apparatus of DCT and DWT coefficients and a method thereof are provided to perform IDCT or IDWT with respect to a compact image, thereby performing cross transformation of the DCT and DWT coefficients through a simple method. A first basic matrix calculator(120) calculates a first basic matrix by multiplying a forward DWT(Discrete Wavelet Transform) conversion matrix of NxN size, defined in DWT compaction standards, by a matrix of NxN size which is a front matrix of a 8x8 DCT conversion matrix, where diagonal components are defined in DCT(Discrete Cosine Transform) compaction standards, and which is configured with 8x8 0 matrix where elements are all 0. A second basic matrix calculator(130) calculates a second basic matrix by multiplying a matrix of MxM size, which comprises 8x8 matrix where elements are all 0 and which is a 8x8 DCT conversion matrix where diagonal components are defined in DCT compaction standards, by a front matrix of a forward DWT conversion matrix of MxM size defined DWT compaction standards. A DWT coefficient calculator(140) calculates a two dimensional one level DWT coefficient by multiplying the first basic matrix, the two dimensional 8x8 DCT coefficient and the second basic matrix.