Method and apparatus for moving picture coding

A moving picture coding apparatus comprising:

• a picture input section that inputs an original moving picture;
• a base layer coding section that extracts one base layer from said original moving picture and codes the base layer;
• a base layer decoding section that decodes the base layer coded by said base layer coding section and reconstructs the base layer;
• a residual picture generation section that generates a residual picture between the reconstructed picture reconstructed by said base layer decoding section and said original moving picture;
• an important area detection section that detects an important area from said original moving picture;
• a gradual shift map generation section that sets bit shift values gradually according to the degree of importance of the important area extracted by said important area detection section;
• a DCT section that DCT-transforms the residual picture generated by said residual picture generation section;
• a bit shift section that bit-shifts the DCT coefficient obtained by said DCT section by the bit shift value obtained by said gradual shift map generation section;
• a bit plane VLC section that performs VLC processing for each bit plane bit-shifted by said bit shift section;
• and
• an enhancement layer division section that divides the moving picture stream VLC-processed by said bit plane VLC section as an enhancement layer into at least one portion.