JP2016152620A5 - - Google Patents

Description

For example, the fragmentation indicator is a binary 2-bit value. Data Unit top in which MMT packet # 1 of Fragment ation indicator of, Fragment ation indicator of MMT packet # 5 is the last, and the Fragment ation indicator from MMT packet # 2 is between a packet to MMT packet # 4, Each is set to a different value. Specifically, Fragment ation indicator of MMT packet # 1 is the head of the Data Unit is set to 01, Fragment ation indicator of MMT packet # 5 is the final is set to 11, MMT packet # is between packet Fragment ation indicator from 2 to MMT packet # 4 is set to 10. When only one MMT packet is included in the data unit, the fragmentation indicator is set to 00.

Therefore, the receiving apparatus 200 can identify the MMT packet storing the pre-slice segment data by using one of the fragmentation indicator and the fragment counter. In addition, the receiving apparatus 200 can identify the MMT packet storing the Nth slice segment by referring to the Fragment counter.

The transmitting apparatus 100 may store identification information indicating an in-plane division method in the access unit in an MMT message, a TS descriptor, or the like. For example, information indicating the number of divisions in the horizontal direction and the vertical direction in the plane may be stored. Or, identification information unique to the division method, such as being divided into two equal parts in the horizontal direction and the vertical direction as shown in FIG. 3, or being divided into four equal parts in the horizontal direction as shown in FIG. May be assigned. For example, when the access unit is divided as shown in FIG. 3, the identification information indicates mode 2, and when the access unit is divided as shown in FIG. 1, the identification information indicates mode 1. .

The value of Offset is a value different from 0, and the start of the payload of the packet the value of Fragmentation ind i CATOR is 00 or 01 is a first slice segment.

FIG. 21 is a diagram for explaining the data transmission order. When MMT is applied to broadcasting, as shown in FIG. 21A, transmission is carried on MMT packets in the order of MPU configuration (transmission in order of MMT packets # 1, # 2, # 3, # 4, and # 5). Then, there is a delay due to encapsulation in the transmission of the MMT packet.

Each transmission method shown in FIG. 21, first, MPU metadata, M F metadata, constituting the MPU data in the order of the media data.

In FIG. 21, MPU data, MPU metadata, M F metadata is configured in the order of the media data, in moof, position information of the samples and each sub-sample (offset) determined based on the configuration It has been. The MF metadata includes data (box size and type) other than the media data in the mdat box.

In FIG. 21, MPU data, MPU metadata, M F metadata, is constituted in the order of the media data, configured the MPU data in a different order from that in FIG. 21, it is determined position information (offset) Also good.

In addition, even when it is determined in step S25 that MF metadata is included, the reception device 20 may acquire the NAL unit using the process of step S27 without using the process of step S26. Further, MF when it is determined that the meta data is included, the processing performed in steps S2 7 in step S2 6 may be used in combination.

First, the receiving device 20 receives an MMT packet and analyzes a packet header and a payload header (S501). Next, the receiving apparatus 20 analyzes whether the fragment type is auxiliary data or MF metadata (S502). If the fragment type is auxiliary data, the receiving apparatus 20 overwrites and updates past auxiliary data (S503). . At this time, when there is no past auxiliary data of the same MPU, the receiving apparatus 20 uses the received auxiliary data as new auxiliary data as it is. Then, the receiving device 20 acquires a sample based on the MPU metadata, auxiliary data, and sample data, and performs decoding (S50 4 ).

On the other hand, the granting unit 302 is an example of sample data (sample data not including information related to synchronization) for which the presentation time is not defined. The non- timed-MFU header (header information) includes MP4 such as item_id. Include configuration information.

The fragment counter indicates the number of a plurality of pieces of divided data after the divided data among a plurality of pieces of divided data obtained by dividing one file. The fragment counter indicates a remainder obtained by dividing the number of divided data by 256 when the number of divided data, which is the number of pieces of divided data obtained by dividing one file, exceeds 256. In the example of FIG. 54, since the number of divided data is 256 or less, the field value of the fragment counter is (M-divided data number). On the other hand, in the example of FIG. 55, since the number of pieces of divided data exceeds 256, a remainder obtained by dividing (N-divided data number) by 256 ((N-divided data number)% 256).

In the receiving apparatus, by the reception processing using the above signal it can be a Ku decoding operation to underflow or overflow.

Thus, the receiving apparatus 800 can perform the Ku decoding operation to underflow or overflow.

As shown in (b) of FIG. 85, at the time of leap second deletion, as in ( b ) of FIG. 84, the time until the leap second deletion (that is, until 9:00 at the NTP time) is set to C. The time after the leap second deletion (that is, after 9:00: 00: at the NTP time) is set as the D region. Note that the C region and the D region are temporal regions, which are time zones or periods. The MPU time stamp in (b) of FIG. 85 is the same as the time stamp described in FIG. 83, and is a time stamp generated (set) based on the NTP time at the timing of giving the MPU time stamp.

-Information indicating whether the timing at which the time stamp of the MPU is given is the C region or the D region is transmitted to the receiving apparatus as identification information. That is, identification information indicating whether the MPU time stamp is generated based on the NTP time included in the C area or based on the NTP time included in the D area is transmitted to the receiving apparatus.

On the other hand, if it is determined that the leap second adjustment is not performed (No in S2 40 1), the process ends with the normal operation.

Claims (8)

A transmission method for storing data constituting an application in a predetermined data unit and transmitting the data,
Based on the reference time information received from the outside, generate time designation information indicating the operation time of the application,
(I) transmitting the predetermined data unit and (ii) control information indicating the generated time designation information;
The control information stores the generated time designation information and identification information indicating whether the time designation information is time information before leap second adjustment. The transmission method according to claim 1, wherein, in the generation, the time designation information of the predetermined data unit is generated by adding a predetermined time to the time information. The identification information indicates whether or not the time designation information was generated based on the time information from a time before a predetermined period to a time immediately before the time immediately before the leap second adjustment is performed. The transmission method according to claim 1 or 2. The time designation information is UTC (Universal Time Coordinated) time and NPT (Normal Play Time),
The transmission method according to any one of claims 1 to 3, wherein the control information is a UTC-NPT reference descriptor indicating a relationship between UTC time and NPT time. The transmission method according to any one of claims 1 to 4, wherein the reference time information is NTP (Network Time Protocol). A receiving method for receiving a predetermined data unit in which data constituting an application is stored,
(I) storing the predetermined data unit; (ii) time designation information indicating an operation time of the application; and identification information indicating whether the time designation information is time information before leap second adjustment. Receiving control information, and
A receiving method for executing the application stored in the received predetermined data unit based on the received control information. A transmission device that stores data constituting an application in a predetermined data unit and transmits the data,
Based on the reference time information received from the outside, a generation unit that generates time designation information indicating the operation time of the application,
(I) a transmission unit that transmits the predetermined data unit; and (ii) control information indicating the time designation information generated by the generation unit;
The control information stores the time specification information generated by the generation unit and identification information indicating whether the time specification information is time information before leap second adjustment. A receiving device that receives a predetermined data unit in which data constituting an application is stored,
(I) storing the predetermined data unit; (ii) time designation information indicating an operation time of the application; and identification information indicating whether the time designation information is time information before leap second adjustment. A receiving unit for receiving control information,
A receiving device that executes the application stored in the predetermined data unit received by the receiving unit based on the control information received by the receiving unit.