Data encoding apparatus and data decoding apparatus

A data encoding apparatus that is provided with:

• first encoding means for encoding a set of bit data by adding a first error-correcting code thereto,
• second encoding means for encoding the set of bit data encoded by said first encoding means by adding a second error-correcting code thereto, said set of bit data encoded by the first encoding means,
• two-dimensional image generating means for generating a two-dimensional image by arranging the bit data on a specific region in columns and rows, said bit data encoded by said first and second encoding means,
• a relocation map showing the order in which the bit data encoded by said first and second encoding means are rearranged, and
• relocation means for rearranging said encoded bit data on a two-dimensional region according to said relocation map and handing that over to said two-dimensional image generating means,
• a relocation map showing the order in which the bit data encoded by said first and second encoding means are rearranged, and
• relocation means for rearranging said encoded bit data on a two-dimensional region according to said relocation map and handing that over to said two-dimensional image generating means,
• relocation map holding means holding said plurality of relocation maps, and relocation map specifying means which selects a relocation map to be used by said relocation means,
• wherein said relocation map specifying means selects the relocation map in which the direction of the most frequent bit error and the longitudinal direction of the set of said bit data cross each other.