Methods and systems are provided for decoding. In one exemplary embodiment, the method may include detecting a synchronization code at a position selected from a plurality of synchronization code inserting positions. The plurality of synchronization code inserting positions may be positioned at periodic intervals in an input code string, and the input code string may include a multiplexed code string and information indicative of a delimiter of the multiplexed code string. The information may be arranged just after the multiplexed code string or between the multiplexed code string and a subsequent synchronization code. The method may also include demultiplexing the input code string on the basis of the position of the synchronization code detected by the detecting, to produce kinds of compressed codes. The method may further include decoding the compressed codes to output a reconstructed signal, each of the kinds of compressed codes being a variable length code.