Patent ID: 8724024

Claim:
A video synchronization device, comprising: a video signal output device configured to receive video data transmitted from a transmitter in sync with a first clock, through a communication unit; a storage unit configured to store the received video data; the video signal output device configured to read the video data from the storage unit in sync with a reference clock, and display moving images on a display unit; a synchronization adjustment unit including a FIFO buffer and a data bit correction amount detecting unit; the FIFO buffer configured to store the video data and synchronization data corresponding to vertical synchronous signals and horizontal synchronous signals in predetermined units on the basis of a horizontal scanning period; the data bit correction amount detecting unit configured to determine a video data correction amount corresponding to a difference between a bit count of reference video data in one vertical synchronous period of the reference clock, and a bit count of video data in one vertical synchronous period of the first clock; the synchronization adjustment unit configured to perform a small correction to adjust a predetermined horizontal scanning period in accordance with the video data correction amount if a ratio of the number of data bits not including the correction amount, contained in the horizontal scanning periods of a single vertical scanning period, relative to the number of data bits, including the correction amount, contained in the horizontal scanning periods of a single vertical scanning period, is less than or equal to one-hundred parts per million; the synchronization adjustment unit configured to perform a large correction to adjust the predetermined horizontal scanning period in accordance with the video data correction amount if the ratio of the number of data bits not including the correction amount, contained in the horizontal scanning periods of a single vertical scanning period, relative to the number of data bits, including the correction amount, contained in the horizontal scanning periods of a single vertical scanning period, is greater than one-hundred parts per million; wherein the synchronization adjustment unit performs the small correction by distributing the video data correction amount to a plurality of invalid horizontal synchronous periods not contributing to the display of moving images so as to delete or add video data, respectively; and wherein the synchronization adjustment unit performs the large correction by distributing the video data correction amount to both the plurality of invalid horizontal synchronous periods not contributing to the display of moving images and a plurality of valid horizontal synchronous periods contributing to the display of moving images so as to delete or add video data, respectively.