High efficiency encoder and video information recording/reproducing apparatus

A method for transforming data comprising at least the steps of:

• encoding by using an intra-mode at least one field of a video signal to be inputted on a field basis and storing the encoded field of the video signal as a reference picture;
• and
• encoding the other fields of the video signal by using a predictive encoding mode with a motion compensation prediction with respect to the reference picture;
• wherein the encoding step using the intra-mode or the predictive encoding mode include a variable length encoding process,
• the method for transforming data further comprising a step of adding data to the video signal, encoded with the intra-mode or the predictive encoding mode, that is to be ignored during decoding, and dividing and embedding the signal into a plurality of segments having fixed lengths,
• wherein the number of the segments is variable to which the video signal encoded by the intra-mode and the predictive encoding mode is embedded a size of a prediction block for motion detection in the predictive encoding mode is i pixels×j lines (i≠j).