Abstract: Content is received from a content origin and includes a first I frame occurring in the content at an actual start time of an ad segment. The content includes an ad marker comprising an indicated start time of an available segment, and the actual start time is within a predetermined period of the indicated start time. The ad marker is updated to set the indicated start time equal to the actual start time. The predetermined period may be within 0.5 seconds of the indicated start time. A second I frame may be detected in the content, and a signature may be generated for content at the time of the first I frame. The first I frame corresponds to the actual start time in response to the first I frame occurring before the second I frame and in response to the signature matching a signature of a known ad.

Abstract: A video decoding device includes a demultiplexing unit which demultiplexes a video bitstream including video data of an encoded slice, Supplemental-Enhancement-Information having first information indicating a refresh group of segments in gradual refresh, and Supplemental-Enhancement-Information having second information indicating segments where a refresh has completed in a current picture, an extracting unit which extracts the second information from a message which is part of the demultiplexed Supplemental-Enhancement-Information, and a video decoding unit which decodes image data from the demultiplexed video bitstream by using at least inter picture prediction.

Abstract: A video decoding device includes a demultiplexing unit which demultiplexes a video bitstream including video data of an encoded slice, first Supplemental-Enhancement-Information having information indicating segments where a refresh has completed in a current picture, and second Supplemental-Enhancement-Information having information indicating a synchronization starting picture and a synchronization completed picture, an extracting unit which extracts the information indicating segments where a refresh has completed in a current picture from a message which is part of the demultiplexed Supplemental-Enhancement-Information; and a video decoding unit which decodes image data from the demultiplexed video bitstream by using at least inter prediction, wherein the synchronization starting picture is a leading picture within a refreshing period, and the synchronization completed picture is the end position of the refreshing period.