JP6982829B2 - Recording device, recording method and recording medium - Google Patents

Description

The present invention relates to a recording device, a recording method, and a recording medium for multiplexing and recording content.

In advanced BS digital broadcasting or advanced wideband CS digital broadcasting, the MMT / TLV method is adopted as a new multiplexing format in order to strengthen cooperation with transmission by communication. For example, Non-Patent Document 1 discloses a technique for transmitting encoded media data for each packet according to MMT.

Information technology-High efficiency coding and media delivery in heterogeneous environment-Part1: MPEG media transfer (MMT), ISO / IEC-1 DIS

However, no consideration is given to a recording device, a recording method, and a recording medium in which one stream receives and records data divided into a plurality of variable length packets such as the MMT method.

Therefore, an object of the present disclosure is to provide a recording device, a recording method, and a recording medium for recording data in which one stream is divided into a plurality of variable length packets.

In order to solve the above problems, in the recording device according to one aspect of the present disclosure, at least one is a plurality of first packets containing reference time information, and each of the plurality of first packets has a plurality of layers of variable length packet structures. It includes a receiving unit that receives content composed of one packet, and a recording unit that records the received content on a recording medium.

Further, in the recording method according to one aspect of the present disclosure, at least one is a plurality of first packets including reference time information, each of which is composed of a plurality of first packets having a variable length packet structure of a plurality of layers. The content is received, and the received content is recorded on a recording medium.

Further, the recording medium according to one aspect of the present disclosure includes at least one of a plurality of first packets containing reference time information, each of which is composed of a plurality of first packets having a variable length packet structure of a plurality of layers. The content is recorded.

The recording method and the like of the present disclosure can appropriately reproduce the recorded data.

FIG. 1 is a diagram showing an example of the configuration of a BD disc. FIG. 2 is a diagram showing an example of the internal structure of the INFO file. FIG. 3 is a diagram showing an example of the internal structure of the playlist file. FIG. 4 is a diagram showing an example of the internal configuration of the play item. FIG. 5 is a diagram showing an example of the internal configuration of the clip information file. FIG. 6 is a diagram showing an example of the internal configuration of stream attribute information. FIG. 7 is a diagram showing an example of the internal configuration of the entry map. FIG. 8 is a diagram showing an example of the configuration of the TS packet and the source packet in the AV clip. FIG. 9 is a diagram showing an example of the data structure of PMT. FIG. 10 is a block diagram showing an example of the configuration of the reproduction device. FIG. 11 is a block diagram showing an example of the internal configuration of the system target decoder. FIG. 12 is a diagram schematically showing an example of the configuration of an MMT / TLV system stream. FIG. 13 is a diagram showing an example of the configuration of the TLV packet. FIG. 14 is a diagram showing an example of the configuration of an IP packet. FIG. 15 is a diagram showing an example of the configuration of the MMTP packet. FIG. 16 is a diagram showing an example of the configuration of the MMTP payload when the MMT-SI is stored. FIG. 17 is a diagram showing an example of a configuration in which the MMT-SI is stored in the payload area of the MMTP payload. FIG. 18 is a diagram showing an example of the relationship between a plurality of MMT-SI divided into a plurality of MMT-SI and a plurality of MMTP packets storing a plurality of MMT-SI when the MMT-SI is divided into a plurality of units and stored. FIG. 19 is a block diagram showing an example of the configuration of the recording device according to the embodiment. FIG. 20 is a diagram for explaining a portion to be recorded in the broadcast content of the MMT / TLV system. FIG. 21 is a diagram for explaining a case where the MMT-SI is divided and stored in a plurality of MMTP packets. FIG. 22 is a diagram for explaining an example in the case of reconstructing the divided MMT-SI. FIG. 23 is a diagram for explaining another example in the case of reconstructing the divided MMT-SI. FIG. 24 is a flowchart showing an example of the reconstruction process of the MMTP packet. FIG. 25 is a diagram for explaining a encryption method for each aligned unit. FIG. 26 is a diagram showing a recording mode of a recording MMT cipher stream on an optical disc. FIG. 27 is a block diagram showing an example of the configuration of the reproduction device according to the embodiment. FIG. 28 is a diagram for explaining a decoding method for each aligned unit. FIG. 29 is a diagram showing an example of the internal configuration of a playlist when the MPEG-2 TS method and the MMT / TLV method are mixed. FIG. 30 is a flowchart showing an example of the reproduction process of the reproduction apparatus by the TS / MMT mixed flag. FIG. 31 is a diagram showing an example of the internal configuration of the clip information file in the MMT / TLV method. FIG. 32 is a block diagram showing a functional configuration of the recording device according to the embodiment. FIG. 33 is a flowchart showing an example of a recording method by the recording device according to the embodiment. FIG. 34 is a diagram for explaining the EP course and EP fine of the entry map.

(Knowledge that became the basis of the present invention)
Conventionally, a recording device that receives content multiplexed by the MMT / TLV method or the like and records it on a recording medium has not been sufficiently considered, and for example, it is transmitted together with the content used for reproducing the content. In some cases, the reference time information was not recorded but was recorded on the recording medium. Therefore, it may be difficult for the playback device to reproduce the content recorded on the recording medium.

Hereinafter, a specific description will be given.

In digital broadcasting and content distribution, the MPEG2-TS method is generally used as a multiplexing format for transmission and storage in conventional Standard Definition (SD) image quality and High Definition (HD) content. rice field.

The multiplexing format is a format for treating video signals and audio signals constituting AV contents as one digital data. The digital data in the multiplexing format is, for example, a video signal encoded by the MPEG4-AVC method and an audio signal encoded by the MPEG2-AAC method, which are subdivided into appropriate sizes, and these subdivided data. Is the data to which information for control is added while rearranging the data in the order required for reproduction.

Digital data in Japanese terrestrial digital broadcasting or BS / CS digital broadcasting using the MPEG2-TS method stores video signals and audio signals in units of fixed-length 188-byte size data. .. Here, one unit of data is called a packet, and in the MPEG2-TS system, it is called a TS packet.

The TS packet is composed of a TS header that stores control information and a TS payload that stores an actual video signal or audio signal.

In Japanese terrestrial digital broadcasting or BS / CS digital broadcasting, the TS header has a fixed length of 4 bytes, and the TS payload has a fixed length of 184 bytes in principle. In addition, a part of the TS payload may be used to store additional control information called Adaptation Field.

Further, in the Blu-ray (registered trademark) Disc (hereinafter referred to as "BD disk"), the TS packet is further prefixed with a 4-byte time stamp indicating the read time from the optical disk, and is fixed at 192 bytes. A video signal and an audio signal are stored in an optical disc with long data as one unit. The method used for BD discs is called Time Stamped TS method or TTS method because TS packets are time stamped, and one unit of data is called TTS packet.

Recently, 4K content is attracting attention as a new high-quality content. Conventional High Definition (HD) content is also called 2K content, and the number of pixels is 1920 x 1080, but 4K content doubles the 2K content vertically and horizontally, and the number of pixels is 3840 x 2160. Is to be.

4K content requires four times the capacity of conventional 2K content, but it is said that it is possible to record with about twice the capacity due to recent advances in video compression technology. ..

Further, as a content with higher image quality, 8K content having 7680 pixels in the vertical direction and 4320 in the horizontal direction is also being considered.

In order to transmit 4K content or 8K content by broadcasting waves, the development of advanced BS digital broadcasting and advanced wideband CS digital broadcasting is newly underway.

In these broadcasts, a transmission band of 35 Mbps (35 Mbits per second) in the case of 4K and 100 Mbps (100 Mbits per second) in the case of 8K is assumed. Optical discs for storing these broadcasts are also being studied.

Further, in advanced BS digital broadcasting and advanced wideband CS digital broadcasting, the MMT / TLV method is adopted as a new multiplexing format in order to strengthen cooperation with transmission by communication.

The digital data in the MMT / TLV system subdivides the video signal and audio signal into appropriate sizes as in the conventional MPEG2-TS system, rearranges these subdivided data in the order required for reproduction, and controls the data. It is the data to which the information for is given.

The major difference from the conventional MPEG2-TS method is that the size of the subdivision at this time is not necessarily fixed, but has a variable length. That is, the size of the subdivision in the MMT / TLV method is not a fixed size as in the MPEG2-TS method, but different sizes.

Further, unlike the conventional MPEG2-TS method, the MMT / TLV method needs to process a four-layer data structure before accessing the area in which the actual data is stored.

In the MMT / TLV system, the receiving device that receives the TLV packet first processes the header portion from the TLV packet of the TLV system to acquire the TLV payload in which the IP packet is stored. Next, the receiving device processes the header portion of the IP packet stored in the TLV payload to acquire the IP payload in which the UDP packet is stored. Further, the receiving device processes the header portion of the UDP packet stored in the IP payload to acquire the UDP payload in which the MMTP packet is stored. Finally, the receiving device can access the area where the actual data is stored by processing the header portion of the MMTP packet.

The headers of TLV packets, IP packets, and UDP packets are information required for transmission in broadcasting, but are not required for recording on an optical disk. Therefore, from the viewpoint of reducing the amount of data, It is desirable to delete this information before recording it.

However, in the MMT / TLV method, the reference time information of the entire content is recorded in the NTP packet stored as the TLV packet, and when the content is recorded as the MMTP packet, the reference time information is from the content. Missing. For this reason, there is a problem that the reproduction process cannot be performed correctly in time synchronization.

In order to solve such a problem, in the recording device according to one aspect of the present disclosure, at least one is a plurality of first packets including the reference time information, and each of the plurality of recording devices has a plurality of layers of variable length packet structure. It includes a receiving unit for receiving the content composed of the first packet of the above, and a recording unit for recording the received content on a recording medium.

Therefore, the content recorded on the recording medium can be appropriately time-synchronized and reproduced by the playback device.

Further, the recording unit may (i) record the first reference time information of one or more reference time information included in the plurality of first packets as the reference time of the content and the content included in the management information of the content. (Ii) The time calculated by adding the reproduction time of the content to the reproduction start time may be recorded as the reproduction end time of the content included in the management information.

Therefore, the content recorded on the recording medium can be appropriately time-synchronized and reproduced by the playback device.

Further, the recording unit records (i) the start position information indicating the reproduction start position of the content in the recording medium in the management information in association with the reproduction start time, and (ii) the recording medium of the content. The end position information indicating the reproduction end position in the above may be recorded in the management information in association with the reproduction end time.

Therefore, it is possible to easily make the playback device specify the recording position of the content recorded on the recording medium. Therefore, it is possible to appropriately synchronize the time and reproduce the image in the reproduction device.

Further, each of the plurality of first packets is a TLV packet multiplexed by the MMT / TLV method, and the reference time information may be time information indicating a time based on NTP (Network Time Protocol). ..

Therefore, even when the content multiplexed by the MMT / TLV method is received, the content is recorded on the recording medium together with the reference time information, so that the content recorded on the recording medium is appropriately time-synchronized and played back. It can be regenerated by the device.

Further, the recording unit includes (i) a plurality of second packets in a layer higher than the first packet from the plurality of first packets of the content received by the receiving unit, and the reference time information. , And (ii) the extracted second packet and the reference time information may be recorded.

According to this, even if the amount of data to be recorded on the recording medium is reduced, the reference time information is recorded on the recording medium, so that the content recorded on the recording medium can be appropriately time-synchronized and reproduced by the playback device. ..

Further, each of the plurality of first packets is a TLV packet multiplexed by the MMT / TLV method, and each of the plurality of second packets is an MMTP (MPEG Media Transport Protocol) packet, and the reference time is described. The information may be time information indicating a time based on NTP (Network Time Protocol).

Therefore, even when the content multiplexed by the MMT / TLV method is received, the content is recorded on the recording medium together with the reference time information, so that the content recorded on the recording medium is appropriately time-synchronized and played back. It can be regenerated by the device.

Further, in the recording method according to one aspect of the present disclosure, at least one is a plurality of first packets including reference time information, each of which is composed of a plurality of first packets having a variable length packet structure of a plurality of layers. The content is received, and the received content is recorded on a recording medium.

Further, the recording medium according to one aspect of the present disclosure includes at least one of a plurality of first packets containing reference time information, each of which is composed of a plurality of first packets having a variable length packet structure of a plurality of layers. The content is recorded.

Here, an embodiment of the present invention will be described with reference to the drawings. However, more detailed explanation than necessary may be omitted. For example, detailed explanations of already well-known matters and duplicate explanations for substantially the same configuration may be omitted. This is to avoid unnecessary redundancy of the following description and to facilitate the understanding of those skilled in the art.

It should be noted that the inventor intends to limit the subject matter described in the claims by those skilled in the art by providing the accompanying drawings and the following description in order to fully understand the present disclosure. No.

(Embodiment 1)
(1) Configuration of BD Disc FIG. 1 is a diagram showing an example of the configuration of a BD disc.

In this figure, the BD disc 101 is shown in the fourth stage, and the track 102 on the BD disc is shown in the third stage. The track 102 in this figure is drawn by stretching the track 102 formed in a spiral shape from the inner circumference to the outer circumference of the BD disc 101 in the lateral direction.

The BD disc 101 has a spiral recording area from the inner circumference to the outer circumference thereof like other optical discs such as DVDs and CDs. The BD disc 101 has a volume area in which logical data can be recorded between the lead-in on the inner circumference and the lead-out on the outer circumference.

A serial number is assigned to the volume area in units of accessing the optical disc from the beginning, and this number is called a logical address. Reading data from an optical disk is performed by specifying a logical address.

Here, the logical address is defined to be continuous even in the physical arrangement on the optical disk. That is, data having consecutive logical addresses can be read without seeking.

Further, inside the read-in of the BD disk 101, there is a special area called BCA (Burst Cutting Area) that can be read only by a drive. Since this area cannot be read from the application, it is used, for example, for copyright protection technology.

In the volume area, the volume information of the file system is recorded from the beginning, and then the application data such as video data is recorded.

A file system is a mechanism that expresses data on an optical disk in units called directories or files. In the case of the BD disk 101, for example, UDF (Universal Disk Form) is used as the file system. Even in the case of a PC (personal computer) that is used on a daily basis, the data recorded on the hard disk in the structure of a directory or file is expressed on the computer by a file system called FAT (File Allocation Tables) or NTFS (NT File System). , Improves usability.

With this file system, it is possible to read the logical data recorded in the same way as a normal PC using a directory or file structure.

In the directory or file structure on the BD disk 101, the BDAV directory is placed directly under the root directory (ROOT). The BDAV directory is a directory in which data such as AV contents and management information handled by the BD disk 101 are recorded. Under the BDAV directory, there are an INFO file, a PLAYLIST directory, a CLIPINFO directory, and a STREAM directory in which a table for managing playlists recorded on the disk is defined.

In addition, AV clips (ZZZZ.M2TS, AAA.MMTS) in which AV contents such as video and audio are multiplexed and stored, clip information files (ZZZZ.CLPI, AAA.CLPI) in which management information of AV clips are stored, and The playlist files (XXX.RPLS, YYY.VPLS) that define the logical reproduction path of the AV clip are arranged under the above-mentioned STREAM directory, CLIPINF directory, and PLAYLIST directory, respectively.

The data structure of each file placed under the BDAV directory will be described below.

(2) Internal configuration of the INFO file First, the INFO file will be described.

FIG. 2 is a diagram showing an example of the internal structure of the INFO file.

The INFO file is composed of the disc information shown in FIG. 2 and the playlist table.

The disc information includes a disc name, a record protection flag, a PIN code, and the like. The disc information defines information related to the content recorded on the BD disc, such as the disc name, the recording protection flag, and the PIN code.

The disk name indicates the name of the disk.

The record protection flag is a flag for preventing the user from accidentally editing or deleting the content recorded on the disk, and indicates that editing is prohibited.

Further, the PIN code is a 4-digit number that can be used to authenticate a user who can view the content recorded on the disc in order to prevent the content recorded on the disc from being inadvertently viewed by another person or the like.

A playlist table is a table that defines all playlists stored on a BD disc. Playlist numbers are specified in this table. When playing a BD disc, the BD disc playback device can be used to list and display the playlists in the playlist table as a program menu.

(3) Internal Configuration of Playlist File Next, the playlist file (XXX.RPLS, YYY.VPLS) will be described.

FIG. 3 is a diagram showing an example of the internal structure of the playlist file.

The playlist shows the reproduction path of the AV clip. As shown in FIG. 3, a playlist is composed of one or more play items 1201. Each play item 1201 refers to a clip information file 1203 indicating a reproduction section for AV clip 1204. The clip information file 1203 shows the reproduction start time and the reproduction end time of the reproduction section of the AV clip 1204, and has the address information corresponding to the reproduction time by the entry map. The details of the entry map will be described later. Each play item indicates the start time and end time of the section designated as the playback path within the range of the playback section indicated by the clip information file to be referenced. Each play item 1201 is identified by a play item ID and is described in the order in which it should be played in the playlist.

The playlist also includes an entry mark 1202 indicating a playback start point. The entry mark 1202 is given to the reproduction section defined by the play item, is attached to a position that can be a reproduction start point with respect to the play item as shown in FIG. 3, and is used for cue reproduction. The reproduction path of a series of play items is defined here as the main path 1205.

Here, there are two types of files in the playlist file. One is a real playlist (XXX.RPLS). Real playlists are used to manage AV clips recorded on BD discs.

All sections of the AV clip recorded on the BD disc are associated one-to-one with the play items in the real playlist. Therefore, the playback device can play back all the AV clips recorded on the BD disc by referring to the real playlist. When the real playlist is deleted, the AV clip associated with the real playlist is also deleted.

The other is a virtual playlist (YYY.VPLS). By using the virtual playlist, the user can freely edit the playback path of the AV clip. In the virtual playlist, a part of the AV clip may be referred to, or the AV clip may be referred to in duplicate. Also, even if the virtual playlist is deleted, the AV clip referenced in the virtual playlist is not deleted.

Real playlists and virtual playlists can be distinguished by the extension. In addition, the playlist numbers (XXX and YYY) of the real playlist and the virtual playlist must not be duplicated.

(4) Internal configuration of play item FIG. 4 is a diagram showing an example of the internal configuration of a play item.

The configuration of the play item will be described with reference to FIG.

The play item includes reference information 1301 indicating an AV clip to be reproduced, a connection condition 1302, a reproduction start time 1303, and a reproduction end time 1304.

The reproduction start time 1303 and the reproduction end time 1304 are time information. Therefore, the playback device refers to the entry map of the clip information file, acquires the position information in the clip corresponding to the playback start time 1303 and the playback end time 1304 specified in the play item, and specifies the read start position. And perform the playback process.

The connection condition 1302 indicates the connection type with the forward play item.

When the connection condition 1302 of the play item is "1" or "2", it means that the AV clip pointed to by the play item is not guaranteed to be seamlessly connected to the AV clip pointed to by the play item before the play item. The difference between the play item connection condition 1302 being "1" and "2" is that the clips referenced by the previous play item and the current play item are consecutive STC sequences in the same clip. The difference is whether or not there is.

The fact that the connection condition 1302 of the play item is "3" or "4" guarantees that the AV clip pointed to by the play item is seamlessly connected to the AV clip pointed to by the play item before the play item. Show that.

When the connection condition 1302 is "4", it means that the AV clip referred to by the forward play item has been terminated under the condition that seamless connection is possible. On the other hand, when the connection condition 1302 is "3", a part of the vicinity of the connection point is cut out when the termination process is not performed under the condition that the AV clip referred to by the forward play item can be seamlessly connected. It is shown that seamless connection is guaranteed by using a bridge clip that has been terminated.

(5) Internal Configuration of Clip Information File FIG. 5 is a diagram showing an example of the internal configuration of the clip information file.

Subsequently, the clip information file (ZZZ.CLPI) will be described with reference to FIG.

The clip information file is management information of the AV clip, and has a one-to-one correspondence with the AV clip. The clip information file is composed of clip information, stream attribute information, and an entry map.

The clip information is composed of a system rate, a playback start time, and a playback end time. The system rate indicates the maximum transfer rate of the AV clip to the PID (Packet ID) filter of the system target decoder described later. The playback start time is the display time (PTS) of the video frame at the beginning of the AV clip. The playback end time is the time obtained by adding the playback interval for one frame to the display time (PTS) of the video frame at the end of the AV clip.

(6) Internal Configuration of Stream Attribute Information FIG. 6 is a diagram showing an example of the internal configuration of stream attribute information.

As shown in FIG. 6, the stream attribute information includes the attribute information of each of the one or more streams included in the AV clip. Each of the one or more attribute information included in the stream attribute information corresponds to the PID of one or more streams. One or more attribute information corresponds to each of a video stream (video stream), an audio stream (audio stream), and a subtitle stream, and is different from each other.

The attribute information of the video stream includes information such as the compression codec in which the corresponding video stream is compressed, the resolution of the individual picture data constituting the video stream, the aspect ratio of the picture data, and the frame rate of the video stream.

The attribute information of the audio stream includes information such as a compression codec in which the corresponding audio stream is compressed, the number of channels included in the corresponding audio stream, and the sampling frequency of the audio stream.

This information is used for initialization of the decoder of the reproduction device performed before the reproduction device reproduces.

(7) Internal configuration of the entry map FIG. 7 is a diagram showing an example of the internal configuration of the entry map.

As shown in FIG. 7A, the entry map includes the entry map header information 1101, the time information indicating the display time of each I picture of the video stream included in the AV clip, and the AV clip at which each I picture starts. It is the table information in which the position information of is described. The position information of the AV clip is indicated by SPN (Source Packet Number) in the case of the MPEG-2 TS method, and is indicated by the number of bytes from the beginning of the AV clip in the case of the MMT method.

Here, the paired time information and position information shown in one row of the table are called entry points. Further, the value incremented for each entry point with the beginning as 0 is referred to as an entry point ID (hereinafter referred to as "EP_ID"). By using this entry map, the playback device can identify the file position of the AV clip corresponding to an arbitrary point on the time axis of the video stream. For example, in the case of special playback such as fast forward and rewind, the I picture registered in the entry map is specified and played from the specified I picture to efficiently process the AV clip without analyzing it. Can be done. Further, the entry map is created for each video stream multiplexed in the AV clip and is managed by PID. Further, the entry map header information 1101 is stored at the beginning of the entry map. The entry map header information 1101 stores information such as the PID of the video stream pointed to by the entry map and the number of entry points.

Subsequently, AV clips (ZZZ.M2TS, AAA.MMTS) will be described.

There are two types of AV clip methods: an MPEG-2 TS system digital stream (ZZZ.M2TS) and an MMT / TLV system digital stream (AAA.MMTS). Whether it is an MPEG-2 TS type AV clip or an MMT / TLV type AV clip can be determined by their respective extensions. The stream numbers (ZZZ and AAA) must not be duplicated.

First, an MPEG-2 TS type AV clip will be described.

(8) Configuration of TS Packets and Source Packets FIG. 8 is a diagram showing an example of the configuration of TS packets and source packets in an AV clip.

As shown in FIG. 8, the TS packet sequence has a plurality of TS packets. Each of the plurality of TS packets is a 188 BYte fixed-length packet composed of a 4 Byte TS header having information such as a PID for identifying a stream and a 184 Byte TS payload for storing data, and is a PES described above. The packet is split and stored in the TS payload. In the case of BD, a 192 Bite source packet is configured by adding 4 Bite TP_Extra_Header to the TS packet, and each source packet is written in the AV clip. Information such as ATS (Arrival_Time_Stamp) is described in TP_Extra_Header. The ATS indicates the transfer start time of the TS packet to the PID filter of the system target decoder 1503 described later. As shown in the lower part of FIG. 8, the AV clip is composed of a plurality of source packets arranged side by side. The number that increments from the beginning of the AV clip is called the SPN (source packet number).

Further, the TS packet included in the AV clip includes PAT (Program Assessment Table), PMT (Program Map Table), PCR (Program Lock Reference), and the like, in addition to each stream such as video, audio, and subtitles. The PAT indicates what the PID of the PMT used in the AV clip is. The PID of PAT itself is 0. The PMT has the PID of each stream such as video, audio, and subtitles included in the AV clip, and the attribute information of the stream corresponding to each PID. In addition, the PMT has various descriptors related to AV clips. The descriptor includes copy control information indicating whether to allow or disallow copying the AV clip. The PCR is performed on the ATS in which the PCR packet is transferred to the decoder in order to synchronize the ATC (Arrival Time Clock), which is the time axis of the ATS, with the STC (System Time Clock), which is the time axis of the PTS and DTS. Has information on the corresponding STC time.

(9) PMT data structure FIG. 9 is a diagram showing an example of the PMT data structure.

At the beginning of the PMT, a PMT header describing the length of the data included in the PMT is arranged. Behind it, a plurality of descriptors related to AV clips are arranged. The above-mentioned copy control information and the like are described as descriptors. After the descriptor, a plurality of stream information about each stream included in the AV clip is arranged. The stream information is composed of a stream descriptor in which the stream type, the PID of the stream, and the attribute information of the stream (frame rate, aspect ratio, etc.) are described in order to identify the compression codec of the stream. There are as many stream descriptors as there are streams in the AV clip.

(10) Configuration of Playback Device Next, a playback device for playing back a BD disc containing an MPEG-2 TS type AV clip will be described.

FIG. 10 is a block diagram showing an example of the configuration of the reproduction device.

The reproduction device 1500 includes a BD drive 1501, a read buffer 1502, a system target decoder 1503, a management information memory 1505, a reproduction control unit 1507, a user event processing unit 1509, and a plane addition unit 1510.

The BD drive 1501 reads data from the BD disc based on the request from the reproduction control unit 1507. The AV clip read from the BD disc is transferred to the read buffer 1502, and the INFO file, playlist file, and clip information file read from the BD disc are transferred to the management information memory 1505, respectively.

The read buffer 1502 is a buffer composed of a memory or the like for storing data read from a BD disk by the BD drive 1501. The management information memory 1505 is a buffer composed of a memory for storing management information of an INFO file, a playlist file, and a clip information file read from a BD disk by the BD drive 1501.

The system target decoder 1503 performs multiplex separation processing on the source packet stored in the read buffer 1502, and performs stream decoding processing. Information such as the codec type and stream attributes required for decoding the stream included in the AV clip is transferred from the playback control unit 1507. The system target decoder 1503 writes the decoded main video video stream and subtitle stream to the main video plane and the subtitle plane, which are the respective plane memories. Further, the system target decoder 1503 outputs the decoded main audio stream to a speaker or the like. Details of the system target decoder 1503 will be described later.

The user event processing unit 1509 receives the user operation input to the remote controller, and requests the reproduction control unit 1507 to execute the processing according to the user operation. For example, when the fast-forward button or the rewind button is pressed on the remote control, the user event processing unit 1509 executes a process (that is, a fast-forward process or a rewind process) by a command corresponding to the fast-forward button or the rewind button. By requesting the playback control unit 1507 to execute the fast-forward processing or the rewind processing for the AV clip of the currently playing playlist.

The reproduction control unit 1507 controls the BD drive 1501 and the system target decoder 1503 to control the reproduction of the AV clip. The reproduction control unit 1507 interprets the playlist information and controls the reproduction of the AV clip based on the command from the user event processing unit 1509.

The plane addition unit 1510 superimposes the main video plane and the subtitle plane, and displays the video obtained by superimposing them on a screen such as a TV.

(11) Configuration of System Target Decoder FIG. 11 is a block diagram showing an example of the internal configuration of the system target decoder.

The system target decoder 1503 includes a source depacketizer 1503a, a PID filter 1503b, a video decoder 1700, a subtitle decoder 1710, and an audio decoder 1720.

The source depacketizer 1503a extracts the TS packet by interpreting the source packet transferred to the system target decoder 1503, and sends the extracted TS packet to the PID filter 1503b. The source depacketizer 1503a adjusts the input time to the decoder according to the ATS of each source packet when transmitting the TS packet. Specifically, the source depacketizer 1503a PIDs only the TS packet according to the recording rate of the AV clip at the moment when the ATC value generated by the ATC counter and the ATS value of the source packet become the same. Transfer to the filter.

The PID filter 1503b selects the TS packets output from the source depacketizer 1503a in which the PID of the TS packet matches the PID required for reproduction according to the PID, the video decoder 1700, the subtitle decoder 1710, and the subtitle decoder. Transfer to the audio decoder 1720.

The video decoder 1700 includes a TB (Transport Stream Buffer) 1701, an MB (Multiplexing Buffer) 1702, an EB (Elementary Stream Buffer) 1703, a compressed video decoder 1704, and a DPB (Decoded Picture Buffer) 170.

The TB1701 is a buffer for temporarily storing the output TS packet as it is when the TS packet including the video stream is output from the PID filter 1503b.

The MB1702 is a buffer for temporarily accumulating PES packets when outputting a video stream from TB1701 to EB1703. When data is transferred from TB1701 to MB1702, the TS header of the TS packet is removed.

The EB1703 is a buffer for storing pictures in a coded state (I picture, B picture, and P picture). When the data is transferred from MB1702 to EB1703, the PES header of the PES packet is removed.

The compressed video decoder 1704 creates a frame / field image by decoding individual video access units of the video elementary stream at predetermined decoding times (DTS). Since there are MPEG-2, MPEG-4 AVC, HEVC, VC1 and the like as compression coding formats of the video stream multiplexed on the AV clip, the compressed video decoder 1704 switches the decoding method according to the attributes of the stream. The compressed video decoder 1704 transfers the decoded frame / field image to the DPB1705, and writes the corresponding frame / field image to the main video plane at the timing of the display time (PTS).

The DPB1705 is a buffer for temporarily holding the decoded frame / field image. The compressed video decoder 1704 refers to a picture that has already been decoded and is temporarily held in the DPB 1705 when decoding a video access unit such as a P picture or a B picture that is predictively coded between pictures.

The subtitle decoder 1710 extracts and decodes the subtitle stream from the TS packet input from the source depacketizer 1503a, decodes it, and writes the uncompressed graphics data to the subtitle plane at the timing of the display time (PTS).

The audio decoder 1720 has a buffer buffer, and performs decoding processing of an audio stream by removing information such as a TS header and a PES header while storing data in the buffer buffer. Then, the audio decoder 1720 outputs the uncompressed LPCM state audio data obtained by the decoding process to the audio mixer at the timing of the display time (PTS). For compressed encoding formats of audio streams that are multiplexed into AV clips. Since there are AC3, DTS, MPEG-4 AAC, etc., the audio decoder 1720 switches the decoding method of the compressed audio according to the attribute of the audio stream.

Subsequently, the AV clip of the MMT / TLV system will be described.

(12) Configuration of MMT / TLV System Stream FIG. 12 is a diagram schematically showing an example of the configuration of an MMT / TLV system stream.

The MMT / TLV system stream is composed of a four-layer structure of TLV packets, IP packets, UDP packets, and MMTP packets. That is, the MMT / TLV method is composed of a structure having a plurality of layers.

The stream is composed of one or more variable length TLV packets. Each of the one or more TLV packets is composed of a TLV header and a TLV payload. The TLV payload is variable length and contains variable length IP packets.

An IP packet is composed of an IP header and an IP payload. Here, the IP header is basically a fixed length, but it may have a variable length when there is optional data.

Further, in the MMT / TLV method used for 4K / 8K broadcast contents, there is a case where a compressed format is used as an IP header. This takes advantage of the fact that the information such as the size and address described in the IP header does not change much in the case of broadcasting, and records all information only in some IP packets, and other IP packets. Then, the size of the information to be recorded as "same as before" is reduced. In this case, the length is different from that of a normal IP header. The IP payload has a variable length.

Further, a variable length UDP packet is stored in the IP payload. A UDP packet is composed of a UDP header and a UDP payload. In some cases, the UDP header is compressed together with the IP header.

Finally, the UDP payload contains variable length MMTP packets. The MMT packet is composed of an MMTP header and an MMTP payload. The MMTP header includes at least the MMTP basic header. The MMTP basic header is basically fixed length, but it can also be variable length when there is optional data. The MMTP header may also have an MMTP extension header after the MMTP basic header. The MMTP extension header stores, for example, information related to the control of cryptographic processing. Some MMTP extension headers have a fixed length and some have a variable length. The MMTP header is followed by the MMTP payload. The MMTP payload stores divided video signals, audio signals, and the like.

(13) Configuration of TLV Packet FIG. 13 is a diagram showing an example of the configuration of a TLV packet.

As described above, the TLV packet is composed of a TLV header and a TLV payload. At the beginning of the TLV header, a value of 01 in binary is always described for 2 bits as a delimiter indicating the beginning. Following this delimiter, the TLV header is provided with a 6-bit future expansion field. At the moment, all of this field is set to a value of 1, but if expansion is required for some reason in the future, a value of zero may be described here.

Next, in the TLV header, an 8-bit packet_type indicating the type of data stored in the payload of the TLV packet is stored.

As described above, the content of the TLV payload is an IP packet in principle, but there are cases where an IPv4 packet is stored and a case where an IPv6 packet is stored. Further, in the case of broadcasting, since the value of the IP header in the IP packet is a substantially constant value, there may be a compressed IP packet in which the IP header is described in a compressed format. Further, instead of the IP packet, TLV-SI (Service Information), which is control information for the receiver to demultiplex the IP packet multiplexed on the broadcast transmission line, may be stored in the TLV payload. Furthermore, since broadcasting transmitted in real time does not necessarily transmit meaningful data at all times, it is possible to store a null packet to fill the gap in the TLV payload. The above-mentioned packet_type is used to indicate whether any of these IP packets, compressed IP packets, TLV-SI, and null packets is stored in the TLV payload.

Here, the TLV / IP processing module 203 shown in FIG. 19, which will be described later, outputs the data stored in the TLV payload to the control module 204 as control information when the data is TLV-SI. ..

Since the TLV-SI is transmitted in plain text, it is not necessary to perform decoding processing or the like. The control module 204 controls the operation of the TLV / IP processing module 203, the MMT processing / decoding module 205 described later, or the demulti / decoding module 306 according to the control information described in the TLV-SI.

Further, when the data stored in the TLV payload is a null packet, the TLV / IP processing module 203 simply ignores it. On the other hand, when the information in the TLV payload is an IP packet or a compressed IP packet, the TLV / IP processing module 203 further continues processing related to the IP packet.

(14) Structure of IP Packet FIG. 14 is a diagram showing an example of the configuration of an IP packet.

In FIG. 14, only the case of an uncompressed IPv6 packet is shown as a representative example. The behavior is different when it is in the compressed format or when it is IPv4, but the explanation is omitted because it is irrelevant to the purpose of the present application.

As described above, the IP packet is composed of an IP header and an IP payload. As shown in FIG. 14, a 4-bit version indicating the version is described at the beginning of the IP header. If it is IPv6, 6 is specified at the beginning of the IP header.

The subsequent 8-bit traffic_class is a field that defines the priority regarding the handling of the IP packet. In the case of broadcasting, traffic_class is always set to 0 and is operated without any priority.

The following 20-bit flow_label can store information regarding control of communication. In the case of broadcasting, flow_label is always operated as 0.

The following 16-bit payload_length is information indicating the byte length of the IP payload. Payload_length is a field for indicating that a variable length IP payload is handled.

The following 8-bit next_header indicates a header following the IP header. For next_header, a fixed value "0001 0001" is described because the UDP header always comes next in the case of broadcasting.

Then, 8-bit hop_limit indicating the maximum number of relayable by the router, 128-bit source_addless indicating the IP address of the distribution source, and 128-bit destination_addless indicating the IP address of the distribution destination follow. Since hop_limit, source_addless and destination_addless are irrelevant to the purpose of the present application, detailed description thereof will be omitted.

Next, immediately after the IP header, the UDP header of the UDP packet follows as shown in FIG.

The UDP header consists of 16-bit source_port, destination_port, length, and check_sum fields, respectively. Among them, lens indicates the total size of this UDP header and the subsequent UDP payload in bytes. Since each item of source_port, destination_port, and check_sum is irrelevant to the purpose of the present application, the description thereof is omitted.

The UDP header is followed by a variable length UDP payload.

Variable length MMT packets are usually stored in this UDP payload. The reason why it is written as normal here is that a UDP packet in NTP format for outputting the time to the receiving device may be output in addition to the MMT packet. In the case of IPv6, when FF02 :: 101 is specified as the destination IP address, the NTP information is included in this IP payload. Since the NTP format IP packet is also transmitted in plain text, it is not necessary to perform any decryption processing.

The MMT encrypted stream obtained by processing the TLV header in the TLV packet, the IP header in the IP packet, and the UDP header in the UDP packet described above by the TLV / IP processing module 203 described later is MMT processed. -It is output to the decoding module 205.

(15) Configuration of MMTP Packet FIG. 15 is a diagram showing an example of the configuration of an MMTP packet.

The MMTP packet is composed of an MMT header and an MMTP payload. The MMTP packet includes at least the MMTP basic packet.

The MMTP basic packet first starts with a 2-bit version. version indicates the version number of the MMT protocol, and 00 is specified in this field.

In the next 1-bit packet_counter_flag, it is specified whether or not the packet_counter field described later exists. packet_counter_flag is "1" if it exists, and "0" if it does not exist. The size of the MMTP basic header changes depending on the value of packet_counter_flag. In the case of 4K / 8K broadcasting in Japan, "0" is always specified for packet_counter_flag, and the packet_counter field is not operated.

The 1-bit extension_flag is a 1-bit flag that specifies whether or not the MMTP extension header is present. extension_flag is "1" when the MMTP extension header is present, and is "0" when the MMTP extension header is not present. Depending on the value of extension_flag, the size of the entire MMTP header and the size of the entire MMTP packet will change.

The 6-bit payload_type is a flag indicating the data structure of the MMTP payload, particularly the header portion. For payload_type, "0" is specified in the case of an MMTP payload that stores actual contents such as video and audio, and "2" is specified in the case of an MMTP payload that stores MMT-SI which is control information.

The 16-bit packet_id is information for identifying the type of data stored in the corresponding MMTP payload. Depending on the value of this packet_id, it is possible to indicate whether the data stored in the payload is a video signal, an audio signal, control information (MMT-SI), or the like.

Here, when the data stored in the MMTP payload is MMT-SI, the contents of the MMT-SI are further identified, and if necessary, the control module 204 or the CAS module 206 shown in FIG. 19 is used. It is output. Here, the information that needs to be output to the CAS module 206 is used for EMM (Enterprise Management Message) including contract information for each subscriber and a work key for decrypting common information, or information related to a program and decryption. It is an ECM (Information Control Message) including a necessary key and the like. The other information is output to the control module 204, and the control module 204 is used to control the MMT processing / decryption module 205 and the MMT encryption module 207 according to the contents thereof. The MMT-SI is basically plain text, and it is not necessary for the MMT processing / decoding module 205 to perform decoding processing. However, although the EMM or ECM is encrypted by another method, this decryption is performed by the CAS module 206. Therefore, EMM or ECM decoding is not performed by the MMT processing / decoding module 205.

The following 16-bit time stamp indicates the time when the first byte of this MMT packet is transmitted from the broadcasting station 201 shown in FIG. 19, and is described by a short NTP time stamp. The items of FEC_type (2 bits), RAP_flag (1 bit), packet_sequence_number (32 bits), and packet_counter (32 bits, option) are irrelevant to the purpose of the present application, and thus description thereof will be omitted.

As described above, when 1 is specified for extension_flag, the MMTP header includes the MMTP basic header followed by the MMTP extension header.

A plurality of MMTP extension headers may be described in one MMTP packet, but FIG. 15 shows an example in which one MMTP extension header is described. The MMTP header may not have the MMTP extension header.

When the MMTP extension header is present, "0x0000" indicating the multi-type header extension is specified in the extension_type of the first 16 bits of the MMTP extension header.

Further, in the following 16-bit extension_length, the size of the MMTP extension header following this information is described in bytes.

The next 1-bit multi-header extension end flag indicates whether this MMTP extension header is the last one. The multi-header extension end flag is specified as "0" when a plurality of MMTP extension headers are described.

The following 15-bit multi-header extension type describes the type of information contained in this MMTP extension header. When the video signal or audio signal to be encrypted is stored in the MMTP payload, the information regarding the control of encryption is stored in the MMTP extension header. In this case, "0x0001" is set for the multi-header extension type.

Next, in the 16-bit extended area length field, the size of this MMTP extended header is described in bytes.

The next 3-bit reserve area is skipped, and the following 2-bit MMT scramble control bit indicates whether the video or audio signal stored in the MMTP payload is encrypted, and the video or audio signal is encrypted. If it is, it will indicate whether to use the even key or the odd key.

The next 1-bit scramble method identification control bit indicates whether or not a scramble method identifier described later is recorded. The 1-bit MMT scramble initial value control bit indicates whether or not the MMT scramble initial value information described later is described. Since the 1-bit message authentication control bit has little relation to the purpose of the present application, the description thereof is omitted.

When the scramble method identification control bit described above is "1", an 8-bit scramble method identifier is described, and the encryption method actually used is determined using the scramble method identifier. When the scramble method identifier is "0x01", it is indicated that the widely used AES encryption method having a key length of 128 bits is used.

In the subsequent 16-bit payload length, the length of the MMT scramble initial value information described later is specified in bytes. Here, since the length of the MMT scramble initial value information is 16 bytes, "0x0010" is specified for this payload length.

Finally, in the MMT scramble initial value information, counter information which is an initial value when the AES encryption method is used is described. When the MMT scramble initial value control bit is 0, the value calculated by using the value of packet_sequence_number or packet_id is used as the counter information instead of the value described in the MMT payload scramble initial value information. ..

(16) Configuration of MMTP Payload When MMT-SI is Stored FIG. 16 is a diagram showing an example of the configuration of the MMTP payload when MMT-SI is stored.

The MMTP payload further has a header area and a payload area.

At the beginning of the header area, a 2-bit fragmentation_indicator indicating whether or not the MMT-SI to be stored in the MMTP payload is divided and recorded is stored.

Normally, one MMTP packet has a size of about 1500 bytes, but the control information to be recorded as MMT-SI may have a size larger than this. In such a case, the MMT-SI is divided and stored in a plurality of MMTP packets.

The fragmentation_indicator is stored in one MMTP packet without being divided, contains the beginning part of the divided MMT-SI, contains the intermediate part of the divided MMT-SI, or is the divided MMT-SI. Indicates whether the end part is included. When the fragmentation_indicator is "00" in binary, it indicates that it is stored in one MMTP packet without being divided. Fragmentation_indicator indicates that if it is "01" in binary, it includes the beginning of the divided MMT-SI. Fragmentation_indicator indicates that if it is "10" in binary, it contains the middle part of the divided MMT-SI. Fragmentation_indicator indicates that if it is "11" in binary, it includes the end of the divided MMT-SI.

In the case of 4K / 8K broadcasting in Japan, there is a stipulation that the maximum number of divisions is three, so in the case of the middle part, it is the second division, and in the case of the last part, it is the third division (preceding). If the division to be performed is the first part, it is guaranteed to be the second).

Since the 1-bit length_extension_flag, the 1-bit aggregation_counter, and the 8-bit fragment_counter are irrelevant to the purpose of the present application, detailed description thereof will be omitted.

(17) Configuration when MMT-SI is stored in the payload area of the MMTP payload FIG. 17 is a diagram showing an example of a configuration when MMT-SI is stored in the payload area of the MMTP payload.

A 16-bit message_id indicating the type of MMT-SI is stored at the beginning of the payload area. MMT-SI includes ECM / EMM related to scramble control, MPT / PLT showing the correspondence between a video or audio stream and an MMTP packet group, and a message_id is assigned to each MMT-SI. ..

The following 8-bit version indicates the version of MMT-SI. The next 32-bit lens indicates the number of bytes in MMT-SI. The number of bytes shown here is not the number of bytes of MMT-SI stored in the MMTP packet, but the number of bytes of MMT-SI before division.

As described above, when the MMT-SI is stored in a maximum of three divisions, the lens field is stored only in the first MMTP packet among the plurality of divided MMTP packets.

(18) Configuration when MMT-SI is divided and stored in a plurality of parts FIG. 18 shows an MMT-SI divided into a plurality of parts and a plurality of MMT-SI when the MMT-SI is divided into a plurality of parts and stored. It is a figure which shows an example of the relationship with a plurality of MMTP packets which store.

One MMT-SI is composed of a header area including message_id, version and length arranged at the head portion, and an actual message portion arranged after the header area. When the MMT-SI is divided into a plurality (three in FIG. 18), the MMT-SI is divided with this data structure as it is. Therefore, the long field in the header area of MMT-SI is stored only in the first MMTP packet.

Here, as described above with reference to FIGS. 15 and 17, the MMTP packet itself contains information indicating the length of the MMTP packet or the payload of the MMTP packet, excluding the length information described at the beginning of the MMT-SI. It should be noted that it does not exist. Note that this problem is caused by the size of the A / V data stored in the MMTP packet being stored in the head area of the MMTP payload when the A / V data is stored in the MMTP packet instead of the MMT-SI. Does not occur.

The MMT-SI thus obtained is output to the control module 204 or the CAS module 206 according to the value of the message_id described above, and appropriate processing is performed for each.

As described above, when the MMT-SI is divided, the MMT processing / decoding module 205 itself cannot determine the length of the MMTP packet. However, by acquiring information on the length of each MMTP packet from the TLV / IP processing module 203 together, the MMT processing / decoding module 205 can perform appropriate processing.

(19) Configuration of Recording Device FIG. 19 is a block diagram showing an example of the configuration of the recording device according to the embodiment.

The recording device 202 includes a TLV / IP processing module 203, a control module 204, an MMT processing / decoding module 205, a CAS module 206, an MMT encryption module 207, a recording module 208, and a recording medium 209.

The AV content is transmitted from the broadcasting station 201 to the recording device 202 as an encrypted stream multiplexed by the MMT / TLV method. The recording device 202 is, for example, a Blu-ray® recorder. Further, the recording device 202 may be a television receiver, a set-top box (STB), or the like by externally attaching an HDD connected via USB.

The broadcast wave received from the broadcasting station 201 is converted from an analog signal to a digital signal by a tuner (not shown) and sent to the TLV / IP processing module 203 as an MMT / TLV system encryption stream.

The TLV / IP processing module 203 removes the TLV header, the IP header, and the UDP header while processing the received MMT / TLV method stream by TLV-SI or NTP as necessary, and further performs TLV-NULL. Perform the disposal process. The TLV / IP processing module 203 outputs the MMT cipher stream obtained by the above processing to the MMT processing / decryption module 205.

The MMT cipher stream output to the MMT processing / decrypting module 205 in this way is once decrypted by the MMT processing / decrypting module 205. The formatted MMT plaintext stream obtained by decoding by the MMT processing / decryption module 205 is output to the MMT encryption module, and is encrypted again by the MMT encryption module 207 to become data to be recorded. The data to be recorded is recorded on the recording medium 209 via the recording module 208.

(20) Recording Part of MMT / TLV Broadcast Content FIG. 20 is a diagram for explaining a recording portion of the MMT / TLV broadcast content.

As shown in FIG. 20, of the received MMT / TLV system broadcast content data, only the portion shown in gray is the target of recording.

For MMT / TLV broadcast content data, in addition to data such as TLV-Null that can be clearly discarded at the time of recording, TLV-SI required for transmission control and time adjustment of the terminal are set. Also includes the NTP required for. That is, the data such as TLV-Null, TLV-SI, and NTP are data that are not necessary for reproducing the recorded content, and may be discarded in order to efficiently use the recording area.

The TLV header, IPv6 header, UDP header, compressed IP header, and other headers are all information given to each MMTP packet for transmission control, and are unnecessary data for playback after recording. , These data may be discarded for efficient utilization of the recording area.

As a result, the data to be recorded is only the MMTP packet containing the MMT-SI and the MMTP packet containing the A / V data.

Note that MMT-SI is used when decoding scrambled broadcasts like ECM / EMM, but once it is re-encrypted as plain text using another key information, the recorded content is played back. Includes data that is not used when doing so. Therefore, even if the data is included in the MMT-SI, it is not necessary to record the data that is not used when the content is reproduced, and the data may be discarded for efficient utilization of the recording area.

Also, not all A / V data need to be recorded. Of the A / V data, for example, audio data for sub-audio may be discarded without being recorded, or additional content data such as data broadcasting content may be discarded without being recorded.

In this way, the MMTP packet group sent to the MMT processing / decoding module 205 after deleting unnecessary data is decoded using the AES-CTR mode.

As described above, in the case of A / V data, the size of the data stored in the MMTP payload is always recorded in the region at the beginning of the MMTP payload. Therefore, the recording device 202 can correctly extract A / V data from one MMTP packet and specify the head position of the next MMTP packet. Similarly, for the MMTP packet that stores the MMT-SI, if the MMT-SI is not separately recorded, the recording device 202 can correctly extract the MMT-SI message and specify the start position of the next MMTP packet. It is possible. However, if the MMT-SI is divided into two or three, this cannot be achieved.

(21) Example of MMT-SI divided and stored FIG. 21 is a diagram for explaining a case where MMT-SI is divided and stored in a plurality of MMTP packets. Hereinafter, the divided MMT-SI is also referred to as a divided MMT-SI.

In the example of FIG. 21, one MMT-SI message is divided into two MMTP packets and recorded. In this case, the recording device 202 starts the first MMTP packet with the MMTP basic header having a fixed length by not operating the packet_counter and the MMTP extended header having a fixed size area and an area with a specified length. From, it is possible to access the beginning of the MMTP extension header and the beginning of the MMTP payload in order. The recording device 202 is composed of a factation_indicator or the like in the first MMTP payload, and can always identify the first header area having a fixed length and access to the beginning of the area in which the MMT-SI is stored. Is. The recording device 202 can also acquire the message_id, version, and lens described at the beginning of the MMT-SI. However, the length that can be obtained here indicates the length of the MMT-SI message before it is divided, not the length of the MMTP payload of the first MMTP packet. Therefore, even if the recording device 202 can acquire the lens, it cannot determine where the MMTP payload ends, nor can it identify the beginning position of the next MMTP basic header.

In order to solve such a problem, the recording device 202 according to the present embodiment reintegrates the divided MMT-SI and stores it in the MMTP packet.

(22) Example of Reconstructing the Divided MMT-SI FIG. 22 is a diagram for explaining an example of reconstructing the divided MMT-SI.

In the example of FIG. 22, one MMT-SI message is divided into three MMTP packets and recorded. In the first and third MMTP packets, the MMTP extension header is recorded in addition to the MMTP basic header, and in the second MMTP packet, only the MMTP basic header is recorded. In such a case, the MMT processing / decoding module 205 acquires a partial MMT-SI message stored in each MMTP payload and reconstructs it into one MMT-SI message. Then, the MMT processing / decoding module 205 stores one MMT-SI message in one MMTP packet. Although it is reconstructed as an MMTP packet having no MMTP extension header in FIG. 22, it may be reconstructed including the MMTP extension header. Further, as described above, in the state of being a group of MMTP packets, the length of each MMTP packet storing the already divided MMT-SI message is not known, but this is the size information of each MMTP packet as TLV / IP. It can be processed by obtaining it from the processing module 203.

(23) Another Example of Reconstructing the Divided MMT-SI FIG. 23 is a diagram for explaining another example of reconstructing the divided MMT-SI.

In some cases, it may be desirable that the size of the MMTP packet group before the reconstruction and the MMTP packet group after the reconstruction do not change. This is because the playback time (number of video frames) and the address in the stream (number of bytes from the beginning) are required when creating the time search map described later. This processing needs to be performed in real time, and is usually processed by the MMT processing / decoding module 205 before the MMT-SI reconstruction processing is performed. Therefore, it is not preferable that the data size changes between before and after processing. In order to solve this problem, as shown in FIG. 23, an MMTP packet containing NULL data may be inserted in order to match the length with the MMTP packet group before reconstruction. Since there is at least an extra MMTP basic header in the case of the divided MMTP packet group, even if the MMTP packet including the NULL data is inserted, it will not be longer after the insertion.

(24) MMTP Packet Reconstruction Process FIG. 24 is a flowchart showing an example of the MMTP packet reconstruction process.

First, the MMT processing / decoding module 205 of the recording device 202 reads out one data of the MMTP packet to be processed in step S1501. Although not shown in this flowchart, at the end of broadcast recording, the data of the MMTP packet cannot be read, so that the loop of the flowchart is exited.

In step S1502, the MMT processing / decoding module 205 determines whether or not the MMTP packet read in step S1501 is an MMTP packet including the divided MMT-SI.

If the MMT processing / decoding module 205 determines that the MMTP packet does not include the divided MMT-SI, that is, if the result is No in step S1502, the process proceeds to step S1503. Specifically, the MMT processing / decoding module 205 is not a divided MMT-SI even if the MMTP packet is a packet containing normal A / V data or even if it is an MMTP packet containing MMT-SI. If so, step S1503 is performed.

In step S1503, the MMT processing / decryption module 205 transmits the target MMTP packet as it is to the MMT encryption module 207, which is a subsequent process, without any particular processing.

On the other hand, if the MMT processing / decoding module 205 determines that the MMTP packet contains the divided MMT-SI, that is, if Yes in step S1502, the process proceeds to step S1504.

In step S1504, the MMT processing / decoding module 205 determines whether or not the MMTP packet includes the trailing MMT-SI. As mentioned above, this determination can be made by referring to the fragmentation_indicator. If the MMT processing / decoding module 205 determines that it is not the end here, that is, if it is No in step S1504, the process proceeds to step S1505.

In step S1505, the MMT processing / decoding module 205 holds the MMT-SI message partially recorded in the MMTP packet in the buffer. In this case, the MMT processing / decoding module 205 temporarily discards the MMTP packet without outputting it. The MMT processing / decoding module 205 is supposed to store the part of the MMT-SI message in the buffer, but if the MMTP packet includes the beginning of the MMT-SI message, it stores the MMTP basic header in the buffer. May be. This is because the MMTP basic header stored here is used when the MMTP packet is output later in step S1506. Further, the MMT processing / decoding module 205 may acquire an MMT-SI message having a different message_id in step S1501 in a state where the MMT-SI message is divided and mixed. In this case, the MMT processing / decoding module 205 causes the buffer described in S1505 to hold a plurality of MMT-SIs having different meshege_ids.

Finally, if the MMT processing / decoding module 205 determines that the MMTP packet is an MMTP packet including the trailing MMT-SI, that is, if yes in step S1504, the process proceeds to step S1506. In step S1506, the MMT processing / decoding module 205 reconstructs the MMTP packet and outputs the reconstructed MMTP packet. As for the reconstruction, as shown in FIG. 22, one obtained by further adding the message of MMT-SI at the end to the message of MMT-SI stored in the buffer shown in step S1505. The MMTP packet is output to the MMT encryption module 207, which is a subsequent process. The MMTP packet acquired in step S1501 is discarded here. Further, as the MMTP basic header of the MMTP packet output to the MMT encryption module 207, the MMTP basic header of the MMTP packet acquired in step S1501 is used, or the MMTP basic header of the MMTP packet is previously held in the buffer in step S1505. The MMTP basic header of the MMTP packet including the beginning of MMT-SI is used. Further, as shown in FIG. 23, the MMTP packet including the NULL data may be output after the reconstructed MMTP packet. At this time, it is basic to use the same MMTP basic header as the MMTP basic header of the MMTP packet output as the MMT-SI message, but only the time stamp needs to be adjusted. That is, an appropriate value is recorded in the timestamp according to the size and transfer rate of the preceding MMTP packet.

The plaintext MMT stream thus formatted is output to the MMT cryptographic module 207 shown in FIG. The MMT encryption module 207 encrypts this MMT stream with a 6144-byte united unit.

(25) Encrypted Unit Encryption Method FIG. 25 is a diagram for explaining an encryption method for each Aligned Unit.

The content to be recorded is encrypted in the MMT encryption module 207 using data called a title key (denoted as Kt in the figure). The MMT cryptographic module 207 separates 6144 bytes of data into the first 16 bytes and the remaining 6128 bytes. The MMT encryption module 207 processes the first 16 bytes with AES_E, which is an encryption process of the AES encryption method, using the title key described above. The MMT encryption module 207 further XORs the data obtained in this way with the data of the first 16 bytes, and then encrypts the remaining 6128 bytes of data using this as a key in the AES-CBC mode. The MMT encryption module 207 obtains 6144 bytes of ciphertext by adding the first 16 bytes of data to the ciphertext data thus obtained. This method is adopted in AACS, which is a copyright protection method of Blu-ray (registered trademark) Disc, and has already been implemented in various LSIs. That is, by using the above method as the encryption method, it is possible to apply encryption without performing new development. In addition, although it is described in the present application that encryption is performed in units of aligned units for the purpose of utilizing the past implementation, the present application is not limited to this. For example, a method of encrypting using the AES-CBC mode in units of 2048 bytes, which is the general sector size of an optical disc, or in units of 64 Kbytes, which is the size of an error correction code block (ECC block) on an optical disc, is also assumed. Can be done.

The recording MMT cipher stream thus obtained is output to the recording module 208 together with the title key used for encryption. The recording module 208 records the title key and the recording MMT encrypted stream together on the recording medium 209. Here, the recording medium 209 is assumed to be an optical disc such as a Blu-ray (registered trademark) Disc, but the recording medium 209 is not limited to this. When the recording device 202 is a television, the recording medium 209 may be an external USB HDD. Further, even when the recording device 202 is a recorder, the recording medium 209 is not necessarily a portable optical disk, but may be an HDD built in the device.

Further, in FIG. 19, for the sake of simplicity, the title key is described as if it is stored in the recording medium as it is, but from the viewpoint of security, the title key is recorded in the recording medium 209 with further protection. Should be. For example, when the recording medium 209 is a built-in HDD, it is desirable that the title key encrypted using the device key of the device is recorded. When the recording medium 209 is an optical disk such as a Blu-ray (registered trademark) Disc, it is desirable that a title key encrypted with a unique media key assigned to each medium is recorded.

(26) Configuration of Content on Optical Disc FIG. 26 is a diagram showing a recording mode of a recording MMT cipher stream on an optical disc.

On the optical disk, the recording MMT encrypted stream is assigned a unique number for each stream, and is recorded as a stream file with a file name of, for example, "XXXXXX.MMTS". Here, "XXXXXX" is a 5-digit number, and each file can be identified by this number. The stream file is divided into 6144-byte units of the aligned unit as described above, and each of the divided plurality of aligned units is encrypted by the encryption method shown in FIG. 25. Although not shown, the title key corresponding to each stream file is also recorded on the optical disc. As described above, it is desirable that the title key is also encrypted with the media key assigned to the media and then recorded as the encrypted title key.

In addition, although it is not necessary when the stream file is normally played back in real time from the beginning, a data structure called a time search map is used for special playback such as fast forward, rewind, and playback from a specified time position. It is preferable to store them together on an optical disk. In the time search map, the recording position from the beginning of the file and the number of frames are recorded in association with each compression unit (called GOP: Group of Pictures or the like) in the compression-encoded video stream. As a result, the reproduction device can instantly identify the recording position on the recording medium, for example, the 1000th frame from the beginning, and can easily reproduce from the 1000th frame.

The MPEG2-TS method, which is a multiplexing method generally used in the past, has a data structure of 192 bytes when a time stamp is attached. The recording position here can be specified in units of this time-stamped TS packet. In MPEG2-TS, using this unit, even a 50 GB optical disc can sufficiently express the recording position with 32 bits.

On the other hand, when the MMT / TLV method is used as the multiplexing method, it is difficult to specify the recording position for each packet because the MMTP packet has a variable length structure. Therefore, the recording position of the file is specified in bytes. Therefore, on a 50 GB optical disk, it is difficult to express the recording position of a file in 32 bits, and it is necessary to express it in 40 bits, for example. However, even in the 32-bit expression, the recording position of the file can be expressed in byte units by devising a counter such as cyclic expression.

(27) Configuration of Reproduction Device FIG. 27 is a block diagram showing an example of the configuration of the reproduction device according to the embodiment.

The reproduction device 302 reproduces the recording MMT cipher stream stored in the recording medium 209 while decrypting it using the title key.

First, the reproduction device 302 reads the title key from the recording medium 209, and sets the read title key in the MMT processing / decoding module 305. This key replaces the scramble key in the recording device 202.

Next, the reproduction device 302 reads the recording MMT cipher stream from the recording medium 209 and outputs it to the MMT processing / decryption module 305. Here, the MMT processing / decryption module 305 decrypts the recording MMT cipher stream encrypted in the aligned unit unit using the set title key.

The MMT processing / decoding module 305 of the reproduction device 302 has the same configuration as the MMT processing / decoding module 205 of the recording device 202. The MMT plaintext stream decoded by the MMT processing / decoding module 305 is output to the demulti-decoding module 306.

(28) Decoding Method of Aligned Unit FIG. 28 is a diagram for explaining a decoding method for each Aligned Unit.

The content to be recorded is encrypted using data called a title key (described as Kt in the figure). The MMT processing / decoding module 305 separates each 6144 bytes of data into the first 16 bytes and the remaining 6128 bytes. The MMT processing / decryption module 305 processes the first 16 bytes with AES_E, which is an encryption process of the AES encryption method, using the title key described above. The MMT processing / decoding module 305 further XORs the data thus obtained with the data of the first 16 bytes, and then decodes the remaining 6128 bytes of data using this as a key in the AES-CBC mode. The MMT processing / decoding module 305 obtains 6144 bytes of plaintext by adding the first 16 bytes of data to the plaintext data thus obtained.

The plaintext MMT stream thus obtained is processed by the MMT processing / decoding module 305. In the case of the recording device 202, information from the TLV / IP processing module 203 is required for the size of each MMTP packet in order to correctly process the MMTP packet including the divided MMT-SI. On the other hand, in the case of the recording MMT cipher stream handled by the reproduction device 302, it is guaranteed that the information regarding the size of the payload always exists in each MMTP packet. As a result, the MMT processing / decoding module 305 can correctly take out the MMS-SI and output it to the control module 304, or output the MMT plaintext stream including the remaining A / V data to the demulti-decoding module 306. Is. The A / V data notified in this way is decoded by the demulti-decode module 306 and displayed by the display module 307.

(29) Mixed Flags As described above, there are various differences between the MPEG-2 TS system AV clip and the MMT / TLV system AV clip, from the data structure to be recorded to the decoding processing method for reproduction. ..

In a real playlist managed in a one-to-one correspondence with an AV clip, the MMT / TLV method and the MPEG-2 TS method are not mixed and managed in the same playlist. In the virtual playlist created by editing by one user, the MPEG-2 TS system AV clip and the MMT / TLV system AV clip may be created in a mixed manner.

As described with reference to FIG. 3, each play item refers to one of the AV clips, but in the reproduction of the virtual playlist, the play items described in the virtual playlist are sequentially reproduced. Therefore, when the recording method of the AV clip is changed to another recording method at the point where the play item described in the virtual playlist is switched, the playback device correctly corrects the switched AV clip unless the decoding process is switched. Cannot be played. Therefore, the playback device needs to know in advance that the AV clips having different multiplexing methods are mixed in the virtual playlist when the playback is performed.

Therefore, as shown in FIG. 29, a TS / MMT mixed flag is provided as playlist information in the virtual playlist file. FIG. 29 is a diagram showing an example of the internal configuration of a playlist when the MPEG-2 TS method and the MMT / TLV method are mixed. If the TS / MMT mixed flag indicates true (TRUE), it means that both the MPEG-2 TS type AV clip and the MMT / TLV type AV clip are present in the virtual playlist. Therefore, the playback device is useful for preparing in advance the decoding process for playing back the AV clips of both types. Further, depending on the reproduction device, there may be a case where only the MPEG-2 TS method and only the MMT / TLV method can be reproduced. In such a reproduction device, by confirming the mixed flag, it is possible to take a method of not presenting the virtual playlist as a reproduction candidate.

(30) Reproduction process using the mixed flag FIG. 30 is a flowchart showing an example of the reproduction process of the reproduction device using the TS / MMT mixed flag.

The playback device acquires playlist information in step S3001.

In step S3002, the playback device acquires the value of the TS / MMT mixed flag from the acquired playlist information, determines whether or not the TS / MMT mixed flag is true, and then determines whether or not the TS / MMT mixed flag is true. It is determined whether or not the multiplexing method is mixed in.

When the value of the TS / MMT mixed flag is true (TRUE), that is, Yes in step S3002, the playback device displays the MPEG-2 TS system AV clip and the MMT / TLV system AV clip in the virtual playlist. Since both of them exist, the activation of both decoders is put on standby at the start of playback (S3003).

After that, in step S3004, the playback device checks which multiplexing method the AV clip referred to by each play item has at the start of playback of the virtual playlist, and depending on the multiplexing method supported by the AV clip. Switch the decoder and play.

On the other hand, when the value of the TS / MMT mixed flag is false (FALSE), that is, when the value of the TS / MMT mixed flag is No in step S3002, the playback device displays the MPEG-2 TS system AV clip and the MMT / TLV system in the virtual playlist. It can be determined that it is only one of the AV clips. Therefore, in step S3005, the playback device checks the multiplexing method of the AV clip referred to by the first play item at the start of playback of the virtual playlist, and activates the decoder corresponding to the multiplexing method of the AV clip. .. Since the playback device is the same as the multiplexing method used for the first play item in the playback of the second and subsequent play items, the multiplexing method is used every time the play items are switched, as in the case of mixing. No need to check.

The mixed case described above can be used not only in the multiplexing method but also in the case where AV clips having different video resolutions are mixed. This is because even if the video resolution changes to a different size, the decoding process may be significantly affected.

When playing back 4K and 8K resolution video contents as compared with the conventional 2K contents, four times and 16 times the memory sizes are required to store the decoded pictures, respectively.

A playback device capable of decoding 8K video secures a memory size for storing 8K resolution pictures, but always secures the memory size required for 8K resolution pictures to play a playlist that does not contain 8K content. It is not necessary, and as a result, all that is required is the memory size required to play the highest resolution video played in the playlist. Therefore, by describing the information indicating which resolution of the video content exists in the playlist information, the playback device can set an appropriate memory size in advance.

In this case, the playlist information is described as, for example, a 2K content existence flag, a 4K content existence flag, and an 8K content existence flag, and if each includes 2K resolution video content, the 2K content existence flag indicates true (TRUE). The 4K content presence flag indicates true (TRUE) if it contains 4K resolution video content, and the 8K content presence flag indicates true (TRUE) if it contains 8K resolution video content. The playlist information is not limited to the above-mentioned flag format, and for example, the largest resolution among the video resolutions included in the playlist may be described.

(31) Time Representation of MMT In the MPEG-2 TS method AV clip, the reproduction time is represented by the STC based on the system time described in the PCR stored in the AV clip.

On the other hand, in the MMT / TLV method, the time stamp is described in the MMTP packet as a short NTP time stamp. Further, in the MMT / TLV method, the basic time corresponding to the PCR of the MPEG-2 TS method is the time described in the NTP packet received separately from the MMTP packet, that is, the UTC time is used as the basic time.

When recording only the MMTP packet or less as an AV clip, it is not possible to acquire the base time from within the AV clip.

In the clip information file described with reference to FIG. 5, the reproduction start time and the reproduction end time of the AV clip are described. In the conventional MPEG-2 TS method, the reproduction start time and the reproduction end time can be defined as the reproduction start time and the reproduction end time by the display time of the video frame based on the STC time.

However, in the MMT / TLV method, there may be a case where the time as a base axis cannot be acquired. The NTP packet is below the TLV packet hierarchy and is included above the MMTP packet hierarchy. Therefore, when recording an MMTP packet or more as an AV clip, the NTP packet is discarded, so that the time that is the basic axis cannot be acquired.

Therefore, when recording only the MMTP packet or more as an AV clip, the time that is the starting point of the NTP packet can be specified as the STC time of the AV clip by describing it in the clip information file.

FIG. 31 is a diagram showing an example of the internal configuration of the clip information file in the MMT / TLV method.

The NTP reference time shown in FIG. 31 indicates the time described in the NTP packet that first appears in the received MMT / TLV stream from the time when the recording device starts recording.

When the AV clip is recorded only by the MMTP packet or more, the time to be the starting point cannot be acquired from the AV clip. Therefore, the playback start time of the AV clip is set with this NTP reference time as the starting point. The playback start time is set to a time obtained by converting the NTP reference time into a 45 kHz system time. The playback end time is set to the time obtained by adding the playback time of the video stream included in the AV clip to the playback start time. That is, when the AV clip is recorded as an MMTP packet or more, the reference time information, the reproduction start time, and the reproduction end time are represented by the following relationships.

NTP reference time = [Time described in the NTP packet that first appeared at the start of recording]
Playback start time = [NTP reference time]
Playback end time = [Playback start time] + [Playback time of video in AV clip]

When the AV clip is recorded as a TLV packet or more, since the NTP packet exists in the AV clip, the NTP reference time can be acquired from the first NTP packet found in the recorded AV clip. Therefore, it is not necessary to describe anything in the clip information. At this time, the reproduction start time may start from 0, for example. The playback end time is set to the time obtained by adding the playback time of the video stream included in the AV clip to the playback start time.

That is, when the AV clip is recorded in the TLV packet or less, the reference time information, the reproduction start time, and the reproduction end time are represented by the following relationships.

NTP reference time = 0
Playback start time = 0
Playback end time = [Playback time of video in AV clip]

Although the playback start time starts from 0, it does not have to be 0 and may be any value.

A recording device that receives the broadcast content of the MMT / TLV system as described above and records the received broadcast content will be described with reference to FIG. 32.

FIG. 32 is a block diagram showing an example of the functional configuration of the recording device according to the embodiment.

The recording device 202 includes a receiving unit 121 for receiving the content and a recording unit 122 for recording the received content on the recording medium 209. The receiving unit 121 is realized by, for example, a receiving antenna and a tuner that receive broadcast waves. The recording unit 122 may be realized by, for example, a dedicated circuit, or may be realized by a memory in which a program is stored and a processor that performs processing using the memory. The recording unit 122 may be composed of the TLV / IP processing module 203, the control module 204, the CAS module 206, the MMT encryption module 207, and the recording module 208 in FIG.

Specifically, the content is an encrypted stream multiplexed by the MMT / TLV method. That is, the content is composed of a plurality of first packets. Each of the plurality of first packets has a variable length packet structure having a plurality of layers. Each of the plurality of first packets is a TLV packet multiplexed by the MMT / TLV method. Further, at least one of the plurality of first packets includes reference time information. The reference time information is time information indicating a time based on NTP. The reference time information is included in the NTP packet.

The recording unit 122 sets the first reference time information of one or more reference time information included in the plurality of first packets as the reference time (NTP reference time) of the content included in the content management information and the reproduction start time of the content. May be recorded as. Further, the recording unit 122 may record the time calculated by adding the reproduction time of the content to the reproduction start time on the recording medium 209 as the content generation end time. The content management information is, for example, clip information of a clip information file.

Further, the recording unit 122 may record the start position information indicating the reproduction start position in the content recording medium 209 in the management information in association with the reproduction start time. Further, the recording unit 122 may record the end position information indicating the reproduction end position of the content recording medium 209 in the management information in association with the reproduction end time.

Further, the recording unit 122 extracts a plurality of second packets in a layer higher than the first packet and a reference time information from the plurality of first packets of the content received by the receiving unit 121, and extracts the plurality of extracted packets. The second packet of the above and the reference time information may be recorded. In this case, each of the plurality of second packets is an MMTP (MPEG Media Transport Protocol) packet.

FIG. 33 is a flowchart showing an example of a recording method by the recording device according to the embodiment.

The receiving unit 121 of the recording device 202 receives the content (S3301).

Next, the recording unit 122 records the content received by the receiving unit 121 on the recording medium 209 (S3302).

(32) Byte Representation of Entry Point FIG. 34 is a diagram for explaining an EP course and an EP fine of an entry map.

In the entry map in the MPEG-2 TS system AV clip described with reference to FIG. 7, the time information indicated by the entry point is represented by 33 bits, and the position information is represented by 32 bits. Further, in the entry map, the difference between the positions of adjacent entry points can usually be expressed by the number of bits sufficiently smaller than 32 bits. Similarly for the time information, the time difference between adjacent entry points can be expressed by the number of bits sufficiently smaller than 33 bits.

Therefore, the time information and the position information of each entry point are described by the lower bits that can express the difference between them. For example, the position information is the lower 17 bits and the time information is the lower 20 bits excluding 9 bits. It is described in 11 bits and is called EP fine. Further, in the position where the time information and the position information of the EP fine overflow, the high-order bits of the time information and the position information are described, and this is called an EP course. That is, the entry point may be represented by a two-layer structure such as EP fine and EP course.

By this method of expressing the position information, the amount of data in the entry map can be reduced and the search process for the entry point can be improved.

The entry map of the MMT / TLV system is also composed of an entry map having a two-stage structure of EP course and EP fine as in the MPEG-2 TS system. The recording target of the time information and the position information managed by this entry map is different from that of the MPEG-2 TS type AV clip.

When the AV clip is an MPEG-2 TS stream, the time information indicates the time based on the system time described in the PCR packet, and the position information indicates the source packet number. On the other hand, when the AV clip is an MMT / TLV system stream, the time information indicates the time based on the UTC time described in the NTP packet, and the position information indicates the number of bytes from the beginning of the clip.

In order to express the position information, the MPEG-2 TS method has a data structure of 192 bytes when a time stamp is attached. Therefore, in the MPEG-2 TS method, the recording position can be specified in units of TS packets with a time stamp. Therefore, using the TS packet unit with a time stamp, it was possible to sufficiently express the recording position with 32 bits even on a 100 GB optical disc.

On the other hand, in the case of the MMT / TLV method, since the MMTP packet has a variable length structure, the position information cannot be specified in packet units, so it is necessary to specify the file recording position in bytes. ..

However, in a 100 GB optical disc, the expression in 32 bits is not sufficient, and the expression in 37 bits is required, for example. However, even with 32 bits, the recording position can be expressed in byte units by devising a counter such as cyclic expression.

Furthermore, the position information expressed by EP fine is also specified in packet units in the conventional MPEG-2 TS method. On the other hand, in the MMT / TLV method, if specified in byte units, the resolution that can be expressed by the MPEG-2 TS method cannot be sufficiently obtained. Therefore, in order to express the resolution equivalent to the MPEG-2 TS method, 1 byte is used. A large amount of data is required.

In the EP course, the position information of coarse intervals is described for all 32 bits in the conventional MPEG-2 TS method. On the other hand, when expressing in byte units of the MMT / TLV system, only the upper 16 bits of the 37 bits of the position information may be expressed. In this case, since 37 bits can be expressed by adding up with the EP fine value that expresses the lower bits, the amount of data in the EP course can be reduced, and the increase in the amount of data in the entire entry map can be reduced. can.

In each of the above embodiments, each component may be configured by dedicated hardware or may be realized by executing a software program suitable for each component. Each component may be realized by a program execution unit such as a CPU or a processor reading and executing a software program recorded on a recording medium such as a hard disk or a semiconductor memory. Here, the software that realizes the recording device, recording method, etc. of each of the above embodiments is the following program.

That is, this program receives to the computer content composed of a plurality of first packets, each of which is a plurality of first packets containing reference time information, each having a variable length packet structure of a plurality of layers. , The recording method of recording the received content on a recording medium is executed.

Although the recording apparatus, recording method and recording medium according to one or more aspects of the present invention have been described above based on the embodiments, the present invention is not limited to the embodiments. As long as it does not deviate from the gist of the present invention, one or more of the present embodiments may be modified by those skilled in the art, or may be constructed by combining components in different embodiments. It may be included within the scope of the embodiment.

The present invention relates to a recorder that receives and records next-generation 4K / 8K broadcasts and content distributions having an MMT / TLV packet structure and records them on a recording medium, and a player that reproduces the recording medium, such as a physical frame defined by a broadcasting standard and a TLV /. Even if the MMT packet, which is the upper layer, is directly recorded without the lower layer such as IP, the multiplexed data can be processed, which contributes to the compression of the data size.

101 BD disk 102 Track 201 Broadcasting station 202 Recording device 203 TLV / IP processing module 204 Control module 205 MMT processing / decryption module 206 CAS module 207 MMT encryption module 208 Recording module 209 Recording medium 1201 Play item 1202 Entry mark 1203 Clip information file 1204 AV clip 1205 Main path 1301 Reference information 1302 Connection condition 1303 Playback start time 1304 Playback end time 1500 Playback device 1501 BD drive 1502 Read buffer 1503 System target decoder 1503a Source depacketizer 1503b PID filter 1505 Management information memory 1507 Playback control unit 1509 User Event processing unit 1510 Plain addition unit 1700 Video decoder 1701 TB
1702 MB
1703 EB
1704 Compressed video decoder 1705 DPB
1710 Subtitle Decoder 1720 Audio Decoder

Claims (12)

A receiving unit that receives content composed of a plurality of first packets including reference time information, each of which has a plurality of layers of variable length packet structures.
A recording unit for recording the received content on a recording medium is provided .
The recording unit uses the first reference time information of one or more reference time information included in the plurality of first packets as the reference time of the content included in the management information of the content and the reproduction start time of the content. Recording device for recording. The recording unit, recording apparatus according to the time calculated by adding the reproduction time of the content before Symbol playback start time to claim 1 for recording a reproduction end time of the content included in the management information. The recording unit is
(I) The start position information indicating the reproduction start position of the content in the recording medium is recorded in the management information in association with the reproduction start time.
(Ii) The recording device according to claim 2, wherein the end position information indicating the reproduction end position of the content in the recording medium is recorded in the management information in association with the reproduction end time. A receiving unit that receives content composed of a plurality of first packets including reference time information, each of which has a plurality of layers of variable length packet structures.
A recording unit for recording the received content on a recording medium is provided.
Each of the plurality of first packets is a TLV packet multiplexed by the MMT / TLV method.
The reference time information is time information indicating a time based on NTP (Network Time Protocol).
Record apparatus. A receiving unit that receives content composed of a plurality of first packets including reference time information, each of which has a plurality of layers of variable length packet structures.
A recording unit for recording the received content on a recording medium is provided.
The recording unit is
(I) From the plurality of first packets of the content received by the receiving unit, a plurality of second packets in a layer higher than the first packet and the reference time information are extracted.
(Ii) The extracted second plurality of second packets and the reference time information are recorded.
Record apparatus. Each of the plurality of first packets is a TLV packet multiplexed by the MMT / TLV method.
Each of the plurality of second packets is an MMTP (MPEG Media Transport Protocol) packet.
The recording device according to claim 5, wherein the reference time information is time information indicating a time based on NTP (Network Time Protocol). At least one is a plurality of first packets containing the reference time information, and each of them receives a content composed of a plurality of first packets having a variable length packet structure having a plurality of layers.
The received content is recorded on a recording medium, and the content is recorded .
In the recording, the first reference time information among one or more reference time information included in the plurality of first packets is recorded as the reference time of the content included in the management information of the content and the reproduction start time of the content. recording method. At least one is a plurality of first packets containing the reference time information, and each receives content composed of a plurality of first packets having a variable length packet structure having a plurality of layers.
The received content is recorded on a recording medium, and the content is recorded.
Each of the plurality of first packets is a TLV packet multiplexed by the MMT / TLV method.
The reference time information is time information indicating a time based on NTP (Network Time Protocol).
Recording method. At least one is a plurality of first packets containing the reference time information, and each receives content composed of a plurality of first packets having a variable length packet structure having a plurality of layers.
The received content is recorded on a recording medium, and the content is recorded.
In the above record,
(I) From the plurality of first packets of the received content, a plurality of second packets in a layer higher than the first packet and the reference time information are extracted.
(Ii) The extracted second plurality of second packets and the reference time information are recorded.
Recording method. At least one is a plurality of first packets containing reference time information, each of which is a recording medium on which content composed of a plurality of first packets having a variable length packet structure having a plurality of layers is recorded .
In the recording medium, the first reference time information among one or more reference time information included in the plurality of first packets is the reference time of the content included in the management information of the content and the start of reproduction of the content. Recorded as time
recoding media. At least one is a plurality of first packets containing reference time information, each of which is a recording medium on which content composed of a plurality of first packets having a variable length packet structure having a plurality of layers is recorded.
Each of the plurality of first packets is a TLV packet multiplexed by the MMT / TLV method.
The reference time information is time information indicating a time based on NTP (Network Time Protocol).
recoding media. At least one is a plurality of first packets containing reference time information, and a plurality of second packets in a layer higher than the plurality of first packets each having a variable length packet structure of a plurality of layers, and the reference time information. A recording medium on which content including is recorded.

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