Patent ID: 8189997

Claim:
A terminal device having a function of recording content on a recording medium and also reading out the content from the recording medium to play back the content, the terminal device comprising: a clock to perform a clocking operation; a determination unit which determines whether the clock is a secure clock to perform a clocking operation in synchronization with standard time data acquired from outside or a self-running clock to autonomously perform the clocking operation; a timestamp file creation unit which is configured to, during recording of the content, create a timestamp file indicating a recording time of the content based on a clocking time of the clock and cause the timestamp file to be recorded on the recording medium, regardless of whether the clock is determined to be the self-running clock or the secure clock; wherein the timestamp file creation unit is configured to, during playback of the content recorded on the recording medium, update the timestamp file of the content to a playback start time of the content or a playback completion time of the content based on a time measured by the clock, in response to a determination by the determination unit that the clock is the self-running clock; and wherein the timestamp file creation unit is configured to, during playback of the content recorded on the recording medium, not update the timestamp file of the content, in response to a determination by the determination unit that the clock is the secure clock.