Patent ID: 7493016

Claim:
A recording device that records a video stream onto a recording medium, comprising: a detecting unit operable to detect sizes of Intra pictures included in the digital stream and output detected values including the Intra picture sizes; a classifying unit operable to classify the detected values into N groups, wherein the classifying unit comprises: a generating sub-unit operable to generate classification patterns used for classifying the detected values into N groups; and a calculating sub-unit operable to calculate a standard deviation of each classification pattern, and the classification by the classifying unit is performed based on one of the classification patterns with a smallest standard deviation; an assigning unit operable to generate assignment information which indicates distribution ranges of Intra picture sizes respectively belonging to the N groups in a one-to-one association with numerical values 1 to N respectively representing the N groups; and a recording unit operable to record an entry map onto the recording medium in association with the assignment information, the entry map representing each Intra picture included in the digital stream using the numerical values 1 to N.