Compatibility in sub-band HDTV coding

An investigation is made on the compatibility of the video formats TV, EDTV, HDTV_int and HDTV_pro in three-dimensional sub-band coding. A more reasonable joint solution is proposed for the issues of bit rate compression, digital transmission evolution and interlace-to-progressive scanning conversion. The diamond shaped spectrum of the conventional HDTV_int signal format is represented by a kind of switching HDTV_int signal which includes three components and motion detection bits (MDB). The first component and the MDB represent TV. The first plus the second component and the MDB represent EDTV. HDTV_pro is split into switching HDTV_int and an extra component. The switching threshold and the length of temporal filter banks are discussed. Based on the proposed method, the transmission system can evolve through four steps: TV, EDTV, HDTV_int and HDTV_pro. Results of bit rate compression are also presented