Method and apparatus for encoding and decoding image information

An information recording medium is provided comprising system data, volume management information data and at least one file containing a data unit of main picture video data and a data unit of sub-picture data of a sub-picture simultaneously reproducible with said main picture. The data units are respectively arranged as at least one pack. The sub-picture pack includes one or more sub-picture packets subsequent to a header of the sub-picture pack and each sub-picture packet contains a packet header and a sub-picture data piece. One or a plurality of said sub-picture data pieces together constitute a header of the data unit, pixel data (PXD) representing the sub-picture, and at least one display control sequence information piece (DCSQ) which contains a group of display control commands for creating upon execution a particular display of said pixel data on a display screen by setting respective display parameters. Thus, the medium contains a sub-picture stored in a very efficient and space saving manner in that the pixel data (PXD) defining the outline or content of the sub-picture is stored independently of the information indicating how the pixel data is to be displayed on a screen upon reproduction. For example pixel position, color, size and timing are determined by the information summarized in the group of display control commands.