Patent ID: 7424210

Claim:
An information reproduction apparatus for reproducing an information storage medium which records a video object unit comprising sub-picture packs, the sub picture packs comprising a first sub-picture unit for a standard definition content and a second sub-picture unit for a high-definition content, the first sub-picture unit comprising a first sub-picture unit header of four bytes, pixel data, and a sub-picture display control sequence table, the second sub-picture unit comprising a second sub-picture unit header of ten bytes, pixel data, and a sub-picture display control sequence table, the first sub-picture unit header comprising size information of the first sub-picture unit of two bytes and a sub-picture display control sequence table start address of two bytes, the second sub-picture unit header comprising a pre-header of two bytes and a post-header of eight bytes, the post-header comprising size information of the second sub-picture unit of four bytes and a sub-picture display control sequence table start address of four bytes, the pre-header of two bytes being 0, and the size information of the first sub-picture unit of two bytes being other than 0, the apparatus comprising: means for reading data of a first two bytes of the first sub-picture unit and data of the first two bytes of the second sub-picture unit; means for determining whether the data of the first two bytes is 0 or other than 0; and means for reproducing the second sub-picture unit by processing four bytes succeeding to the pre-header as the size information of the second sub-picture unit and further succeeding four bytes as a sub-picture display control sequence table start address when the determining means determines that the data of the first two byte is 0, and for reproducing the first sub-picture unit by processing the data of the first two bytes as the size information of the first sub-picture unit and further succeeding two bytes as the sub-picture display control sequence table start address when the determining means determines that the data of the first two byte is other than 0.