CODING METHOD FOR INTERLACE PICTURE INFORMATION

摘要

PURPOSE:To improve the coding compression efficiency by applying the same duplicate orthogonal transformation to each block unit altogether even in the case of the field mode in the unit of blocks of a field unit or even in the case of the frame mode in the unit of blocks of the frame unit. CONSTITUTION:A frame memory 2 integrates interlace picture signals 1-3 to one frame and a horizontal duplicate orthogonal transformation (LOT) section 4 applies LOT to the signal 3 and outputs LOT transformation coefficients 4. A coding mode discrimination section 5 outputs coded mode information 16 being the discrimination result of the signal 3 and a vertical LOT section 8 applies LOT to the coefficients 4 in the vertical direction and outputs transformation coefficients 10. Furthermore, a vertical DCT section 9 switches the coefficients 4 to coefficients 11 resulting from applying DCT transformation or the coefficients 10 and a variable length coding section 14 outputs coded coefficient information 15 from the quantization coefficients 13 outputted from a quantization processing section 12. Thus, a higher coding compression efficiency is obtained by using the information sets 15, 16.