Patent ID: 6963606
Filing Date: 2005-11-08
Classification: H04N

Abstract:
1. A digital signal conversion method comprising the steps of: extracting a predetermined subset from a complete set of orthogonal transform coefficients from each of at least two blocks generated after orthogonally transforming said at least two blocks of a digital signal of a first format, thus producing partial orthogonal transform coefficients comprising less than said complete set of orthogonal transform coefficients from each of said at least two blocks; carrying out inverse orthogonal transform processing of the extracted partial orthogonal transform coefficients of each of said at least two blocks; forming a new coupled block by connecting adjacent blocks represented by said extracted partial orthogonal transform coefficients of each of said at least two blocks; and orthogonally transforming the coupled new block, thus generating a second digital signal of a second format consisting of new orthogonal transform coefficients, said new orthogonal transform coefficients being composed of the predetermined subsets of said orthogonal transform coefficients of each of said at least two blocks; wherein said forming step multiplies a first matrix, a second matrix and a third matrix, so as to form said new coupled block, said first matrix comprising said partial orthogonal transform coefficients, said second matrix comprising two inverse discrete transform matrices on a diagonal and said third matrix comprising discrete transform coefficients.