Referring to FIG. 21a, by applying the above method described with reference to FIG. 20, 1 bit is used for each 16×16 block in a luminance signal, 1 bit is used for a DC signal, and 1 bit is used for an AC signal. Moreover, if a bit of a coded block pattern of 16×16 block is ‘0’ in a luminance signal, there is no additional information in 16×16 block. Yet, if a bit of a coded block pattern is ‘1’, it is possible to additionally use 4 bits for 16×16 block. In particular, it is able to use 1 bit each to indicate whether each 8×8 bock in 16×16 block contains a coded coefficient [FIG. 21b]. In a chroma signal, referring to FIG. 21c, as a DC signal exists in a chroma signal Cr and Cb, if a bit of a coded block pattern is set to 1, it is able to additionally use 1 bit to indicate whether each of the chroma signal components Cr and Cb contains a coded coefficient. Likewise, as an AC signal exists in a chroma signal Cr and Cb, if a bit of a coded block pattern is set to 1, it is able to additionally use 1 bit to indicate whether each of the chroma signal components Cr and Cb contains a coded coefficient.