The encoder and decoder

The encoder and decoder. The encoder comprising: encoding a bit string generation unit, by scrambling an input bit string to generate a plurality of coded bit streams; DC component estimation means, individually or at the same time every m bits of the shifted string generation unit generates coded bits bit string selected bit string having a predetermined width, wherein m is a positive integer, and estimating the DC component of each bit string of the selected; and the bit string extraction unit, the estimation result unit estimated from the DC component from the encoded bit stream bit string is extracted DC component is suppressed.