Reproduction device, time correction method, and program
A signage player includes: a time function configured to count an internal device time. The signage player also includes a time correction calculator configured to acquire a reference time from the outside, for example, an NTS server, at a timing determined in advance and synchronize the internal device time with the reference time; and a time corrector configured to calculate a time correction coefficient defined using a change rate of a time difference, an error change rate (Δ) between the reference time and the internal device time at a timing different from the timing determined in advance and calculate a corrected time acquired by correcting the internal device time using the time correction coefficient.
1. A reproduction device comprising:
a timer configured to count an internal device time;
a time correction calculator configured to acquire a reference time from outside at a timing determined in advance and to synchronize the internal device time with the reference time; and
a time corrector configured to calculate a time correction coefficient defined using a change rate of a time difference between the reference time and the internal device time at a timing different from the timing determined in advance, the time corrector configured to calculate a corrected time by correcting the internal device time using the time correction coefficient,
wherein the time corrector calculates the change rate of the time difference in a period from a timing synchronized with the time difference of a power-off timing to power off at a timing at which a power-off operation is performed and stores the change rate as the time correction coefficient applied to a timing at which a next power-on operation is performed.
2. The reproduction device according to claim 1 , wherein the time correction calculator synchronizes the reference time and the internal device time with each other at a timing at which a power-on operation is performed and does not perform synchronization until a timing at which a power-off operation is performed after synchronization is performed once.
3. The reproduction device according to claim 1 , wherein the time corrector calculates a corrected time corresponding to a predetermined internal device time on the basis of the internal device time synchronized with the reference time at a timing at which a power-on operation is performed and the change rate.
4. The reproduction device according to claim 1 , wherein if the time corrector does not have the change rate which is to be used for calculating the corrected time, the time corrector reflects only an error at the time of synchronization in the corrected time, calculates a change rate of a time difference in a predetermined period, and calculates the corrected time by reflecting the calculated change rate after the change rate is calculated.
5. The reproduction device according to claim 1 , further comprising:
a timer that has an internal clock and performs a timer operation,
wherein the time corrector calculates the corrected time for every predetermined time counted by the timer.
6. The reproduction device according to claim 5 , further comprising:
a content updating unit configured to control update of content to be displayed,
wherein the content updating unit determines update of the content for every predetermined time according to the timer operation of the timer, and
wherein a start time of the timer operation is set using the corrected time.
7. A time correction method performed by a reproduction device, the time correction method comprising:
calculating a corrected time of an internal device time of the reproduction device using a time correction coefficient determined using a change rate of a time difference between a reference time and the internal device time;
calculating the change rate of the time difference in a period from a timing synchronized with the time difference of a power-off timing to power off at a timing at which a power-off operation is performed; and
storing the change rate as the time correction coefficient applied to a timing at which a next power-on operation is performed.
8. A time correction method performed by a reproduction device, the time correction method comprising:
calculating a corrected time of an internal device time of the reproduction device using a time correction coefficient determined using a change rate of a time difference between a reference time and the internal device time; and
calculating a corrected time corresponding to a predetermined internal device time on the basis of the internal device time synchronized with the reference time at a timing at which a power-on operation is performed and the change rate.