WO2018066385A1

WO2018066385A1 - Information processing device, information processing method, and program

Info

Publication number: WO2018066385A1
Application number: PCT/JP2017/034241
Authority: WO
Inventors: 道人石井; 幸一内村
Original assignee: ソニー株式会社; ソニーセミコンダクタソリューションズ株式会社
Priority date: 2016-10-07
Filing date: 2017-09-22
Publication date: 2018-04-12
Also published as: JPWO2018066385A1; JP7034926B2

Abstract

The present technology relates to an information processing device, an information processing method, and a program for making it possible to convert a content format from a first format to a second format having different time axes. The information processing device of the present technology receives first multiplexed data obtained by multiplexing data including a video stream and an audio stream in a first format; converts a first counter value which is included in the first multiplexed data as time information and which has a bit number defined by the first format, into a second counter value having a bit number defined by a second format; stores video data comprising the video stream and audio data comprising the audio stream respectively in packets of the second format; and generates second multiplexed data of the second format including the second counter value as time information. The present technology may be applied in a PC or a video recording device such as a hard disk recorder.

Description

Information processing apparatus, information processing method, and program

The present technology relates to an information processing apparatus, an information processing method, and a program, and in particular, an information processing apparatus and information that can convert a content format from a first format having a different time axis to a second format. The present invention relates to a processing method and a program.

The transmission of content in the next-generation broadcasting standard is performed by MMT (MPEG Media Transport) instead of the conventional MPEG-2 TS. MMT enables transmission of content using not only a broadcast wave transmission path but also a communication transmission path such as the Internet.

JP 2016-103745 A

When receiving and recording MMT content, it is conceivable to record the MMT content as it is, but recording with MPEG-2 記録 TS is also being studied. By recording with MPEG-2 TS, it is possible to make use of the existing MPEG-2 TS assets.

∙ Technology for converting MMT content to MPEG-2 TS content has not been established.

The present technology has been made in view of such a situation, and makes it possible to convert a content format from a first format having a different time axis to a second format.

An information processing apparatus according to an aspect of the present technology includes a reception unit that receives first multiplexed data obtained by multiplexing data including a video stream and an audio stream in a first format; and a time for the first multiplexed data. A conversion unit for converting a first counter value of the number of bits specified by the first format, which is included as information, into a second counter value of the number of bits specified by the second format, and the video stream are configured Video data and audio data constituting the audio stream are stored in the second format packet, respectively, and the second multiplexed data in the second format includes the second counter value as time information. And a multiplexing unit to be generated.

The first format may be MMT, and the second format may be MPEG-2 TS.

The first counter value representing the reference time is represented by 32 + n bits, wherein the time in units of seconds of 1 second or more is represented by 32 bits, and the accuracy of 1 second or less is 2 ⁿ Hz (n is an integer of 24 or more). It can be a counter value. Further, the second counter value representing the reference time is a 42-bit value representing a time of 1 second or more in 33 bits with an accuracy of 90 kHz, and a time of 1 second or less in 9 bits with an accuracy of 27 MHz. It can be a counter value.

The multiplexing unit adds a TS packet including PCR as the second counter value indicating a reference time to the TS packet storing the video data and the TS packet storing the audio data, Second multiplexed data can be generated.

The first counter value representing the presentation time and the first counter value representing the decoding time are expressed in 32 bits as time in seconds of 1 second or more, and 32 + n bits ^where the accuracy of 1 second or less is 2 ⁿ Hz Counter value. Further, the second counter value representing the presentation time and the second counter value representing the decoding time can be set to a counter value represented by 33 bits with an accuracy of 90 kHz.

The multiplexing unit indicates the PTS as the second counter value indicating the presentation time and the decoding time in the TS packet storing the video data and the PES packet that is the source of the TS packet storing the audio data. A DTS as the second counter value can be added.

The multiplexing unit can generate a PES packet including the video data and the audio data belonging to the same MPU based on the MPU sequence number.

A recording control unit for recording TS as the second multiplexed data on a recording medium can be further provided.

The recording medium can be a Blu-ray (registered trademark) Disc.

In one aspect of the present technology, first multiplexed data obtained by multiplexing data including a video stream and an audio stream in a first format is received, and is included as time information in the first multiplexed data, The first counter value having the number of bits defined by the first format is converted into the second counter value having the number of bits defined by the second format. The video data constituting the video stream and the audio data constituting the audio stream are each stored in the packet of the second format, and include the second counter value as time information. Second multiplexed data is generated.

According to the present technology, the content format can be converted from the first format having a different time axis to the second format.

It should be noted that the effects described here are not necessarily limited, and may be any of the effects described in the present disclosure.

It is a figure showing an example of format conversion by an information processor concerning one embodiment of this art. It is a figure which shows the example of conversion of a counter value. It is a figure which shows the protocol stack of the broadcasting system using MMT. It is a figure which shows the structure of an NTP format. It is a figure which shows arrangement | positioning of the TLV packet which stores the IP packet containing the time information of an NTP format. It is a figure which shows the example which comprises an MMTP payload from a video / audio signal. It is a figure which shows the structure of an MMTP packet. It is a figure which shows the meaning of the value of payload_type. It is a figure which shows the structure of MMTP_payload (). It is a figure which shows the structure of MMTP_payload (). It is a figure which shows the structure of MMT-SI. It is a figure which shows the message type and function of MMT-SI. It is a figure which shows the structure of PA message. It is a figure which shows the meaning of the value of message_id. It is a figure which shows the structure of MPT. It is a figure which shows the structure of a MPU time stamp descriptor. It is a figure which shows the structure of a MPU expansion time stamp descriptor. It is a figure which shows the calculation method of PTS and DTS in MMT. It is a figure which shows the structure of TS packet. It is a figure which shows the structure of an adaptation field. It is a figure which shows the structure of a PES packet. It is a block diagram which shows the structural example of information processing apparatus. It is a block diagram which shows the structural example of the MMT signal processing part of FIG. 22, and a recording control part. It is a figure which shows the relationship between the counter value and time in MPEG-2 TS. It is a figure which shows the relationship between the counter value in MMT, and time. It is a figure which overlaps and shows the characteristic of the 33bit counter of MPEG-2 | It is a figure which shows the structure of PCR. It is a flowchart explaining the conversion process of information processing apparatus. It is a block diagram which shows the structural example of a computer.

Hereinafter, embodiments for carrying out the present technology will be described. The description will be made in the following order.
1. Example of format conversion About MMT About MPEG-2 TS 4. Configuration example of information processing apparatus 5. Conversion of counter value 6. Operation of information processing apparatus Modified example

<1. Example of format conversion>
FIG. 1 is a diagram illustrating an example of format conversion performed by an information processing apparatus according to an embodiment of the present technology.

The information processing apparatus 1 is an apparatus such as a recording device, a television receiver, a personal computer, or a set top box incorporating a recording medium such as an HDD (Hard Disk Drive) or an SSD (Solid State Drive). The information processing apparatus 1 receives content such as a television program including video and audio broadcast (distributed) via a broadcast wave transmission path or a communication transmission path such as the Internet. Broadcast wave transmission paths include terrestrial broadcast and satellite broadcast transmission paths.

Content transmission via broadcast wave transmission lines or communication transmission lines is performed by MMT. The information processing apparatus 1 receives multiplexed data obtained by multiplexing a video stream and an audio stream using MMT.

The information processing device 1 is a device that supports reception of MMT content that conforms to ARIB STD-B60 (“Media transport method using MMT in digital broadcasting”). The information processing device 1 is also a device that supports content transmission in accordance with NEXTVF TR-0004 (“Advanced Broadband Satellite Digital Broadcasting Operational Rules”) defined by the Next Generation Broadcasting Promotion Forum.

The information processing apparatus 1 has a function of reproducing the received MMT content and outputting the video and audio of the content from a television receiver (not shown) connected to the information processing apparatus 1.

The information processing apparatus 1 also has a function of converting the received MMT content into MPEG-2 TS content. MPEG-2 TS is defined by ITU-H.222.0.

When converting the format from MMT to MPEG-2 TS, the information processing apparatus 1 acquires the video data and audio data stored in the MMTP (MMT Protocol) packet and stores it again in the TS packet. The information processing apparatus 1 generates a TS (transport stream) by multiplexing a video TS packet and an audio TS packet together with a TS packet storing control information such as SI (Service Information).

At the time of format conversion, the information processing apparatus 1 converts time information included in the MMT content into MPEG-2MTS time information. MMT and MPEG-2 TS are formats with different time axes. The difference in time axis means that at least one of the number of bits of the counter value defining the time and the accuracy (frequency) is different.

The MMT content and the MPEG-2 コンテンツ TS content include, as time information, a counter value that represents the reference time that is the basis of operation, and a counter value that represents PTS (Presentation Time Stamp) and DTS (Decode Time Stamp). .

FIG. 2 is a diagram illustrating an example of counter value conversion.

As shown on the left side of FIG. 2, in MMT, the reference time is included in time information in NTP format.

Although details will be described later, in the NTP format, the reference time is represented by a counter value of 32 + nbit / 2 ⁿ Hz. Here, 32 + nbit / 2 ⁿ Hz indicates that a time of 1 second or more is expressed in units of seconds using 32 bits, and a time of 1 second or less is expressed using nbits. The accuracy of 1 second or less is 2 ⁿ Hz.

NEXTVF_TR-0004 stipulates that n is 24 or more as NTP format operation.

In MMT, PTS and DTS are obtained from the time represented by the counter value of 32 + nbit / 2 ⁿ Hz.

On the other hand, as shown on the right side of FIG. 2, in MPEG-2 TS, the PCR, which is the reference time for the operation, is represented by a counter value of 42 bits / 27 MHz.

In MPEG-2MTS, PTS and DTS are each represented by a counter value of 33bit / 90kHz.

The information processing apparatus 1 converts the MMT reference time represented by a counter value of 32 + nbit / 2 ⁿ Hz into an MPEG-2 TS PCR represented by a counter value of 42 bits / 27 MHz.

Further, the information processing apparatus 1 converts the PTS and DTS in the MMT into the MPEG-2 TS PTS and DTS represented by the 33-bit / 90 kHz counter value, respectively.

The information processing apparatus 1 generates a TS including the time information of the MPEG-2 TS converted in this way.

1, the information processing apparatus 1 records the MPEG-2 装置 TS content generated by converting the MMT content on the recording medium 11 attached to the information processing apparatus 1. The recording medium 11 is, for example, Blu-ray (registered trademark) Disc (hereinafter referred to as BD as appropriate). BD is a recording medium capable of recording MPEG-2 TS files.

The information processing apparatus 1 can record the content transmitted by MMT on the BD. A playback device that supports playback of a BD can play back the content written on the BD by the information processing device 1.

Further, the information processing apparatus 1 transmits the MPEG-2 TS content generated by converting the MMT content via the network 12 such as the Internet. A playback device that supports playback of MPEG-2 TS content can play back the content generated by the information processing device 1.

In this way, by enabling the conversion of MMT content to MPEG-2 TS content, it becomes possible for various devices capable of processing MPEG-2 TS to process the content provided by MMT. Become. In other words, it is possible to utilize the assets of MPEG-2 TS.

<2. About MMT>
<2-1. MMT packet structure>
The MMT will be described. Here, the part related to the processing of the information processing apparatus 1 in the provisions of ARIB STD-B60 will be described. Unless otherwise specified, it is basically according to the provisions of ARIB STD-B60.

FIG. 3 is a diagram showing a protocol stack of a broadcasting system using MMT.

The code of the video signal and audio signal of the program is divided into transmission units of MFU (Media Fragment Unit) / MPU (Media Processing Unit). An MPU that is a unit including data of one or more access units is configured to include a plurality of MFUs.

The MFU is arranged in the MMTP payload, and an MMTP packet is configured by adding an MMTP header. MMTP packets are transmitted using IP packets. One MMTP packet is transmitted as one IP packet.

Also, MMT-SI, which is control information indicating the configuration of a broadcast program, is arranged in an MMTP payload as an MMT control message format, converted into an MMTP packet, and transmitted as an IP packet.

NTP time information described above is also transmitted using IP packets.

FIG. 4 is a diagram showing the configuration of the NTP format.

IP packets in the NTP format specified in IETF RFC 5905 “Network Time Protocol Version 4: Protocol Protocol and Algorithms Specification” are used to provide Coordinated Universal Time (UTC).

NTP uses the accumulated number of seconds from 1:00:00 on January 1, 1900. The NTP format includes reference_timestamp (reference time stamp).

Reference_timestamp indicates the time when the system time was last corrected in NTP long format. The NTP long format is composed of a 32-bit field indicating a second unit and a 32-bit field indicating one second or less.

NEXTVF_TR-0004 specifies that time of 1 second or less is indicated using nbit (n: 24 or more). n is 32 or less.

The time indicated by NTP is expressed as a counter value of a 32 + nbit counter obtained by adding 32 bits representing a time of 1 second or more in seconds and n bits representing a time of 1 second or less. An accuracy of 1 second or less is 2 ⁿ Hz.

N, which is an accuracy of 1 second or less, is indicated by the precision in FIG. n indicates log2 of the accuracy (in seconds) of the system clock.

In ARIB STD-B60, a transmission system and a receiver in a broadcasting system using MMT must satisfy the following requirements.
• The sending system must maintain a clock based on the NTP timestamp.
-In the sending system, the clock and the clock for encoding video and audio are synchronized.
-The receiver must regenerate and hold the clock based on the received time information in NTP format.
-In the receiver, the system clock for holding the clock and the clock for decoding video / audio are synchronized.

FIG. 5 is a diagram showing the arrangement of TLV (Type Length Value) packets that store IP packets including time information in the NTP format in STD-B44.

STD-B323_1 specifies that IP packets, including IP packets containing time information in NTP format, are transmitted using TLV packets. A TLV packet storing an IP packet including time information in the NTP format is arranged at the head of the first slot among the slots assigned for each TLV stream ID.

* By arranging TLV packets that store IP packets that contain time information in NTP format in this way, it becomes possible to suppress delay variation in IP packets that contain time information in NTP format.

The information processing apparatus 1 extracts the IP packet from the TLV packet constituting the TLV stream, and acquires the time information in the NTP format or the video or audio MMTP packet stored in the IP packet.

FIG. 6 is a diagram showing an example in which an MMTP payload is configured from video / audio signals.

In the processing of video signals and audio signals, MPU is the unit of processing. As shown as sample data with a broken line in the middle of FIG. 6, the MPU includes one or more access units, and is a unit that can perform video and audio decoding processing alone. The size of the MPU is arbitrary and can include any number of access units. In a video signal encoded using inter-frame prediction, the MPU needs to be in GOP (Group of Picture) units.

As shown in the middle of FIG. 6, the MPU is composed of MPU metadata including information related to the entire configuration of the MPU, movie fragment metadata including information on encoded media data, and sample data that is encoded media data. The Since one MPU can be composed of one or more movie fragments, there may be a plurality of movie fragment metadata and sample data.

∙ The same sequence number is added to the MPU for each MPU belonging to the same asset. By using the asset ID for identifying the asset and the sequence number of the MPU, each MPU can be distinguished.

MFU is a smaller unit than MPU. The MFU can be extracted from the sample data constituting the MPU. As a method of configuring the MFU, there is a method of configuring the MFU in units of NAL units or access units as shown by the downward arrows in FIG. By configuring the MFU with the media in mind, it is possible to suppress error propagation when transmission quality degradation such as packet loss occurs.

The media for which presentation times such as video components and audio components are designated indicates the presentation time (PTS in MMT described above) in units of MPU. The presentation time of the MPU is specified using a common time axis based on UTC. Therefore, the receiving-side apparatus can present the necessary media components in synchronism regardless of the difference between the transmission path and the transmission source between broadcasting and communication.

As described above, the elements constituting the encoded signal in MMT include MPU, MFU, MMTP packet, and MMTP payload.

FIG. 6 shows an example in which one MFU is stored in one MMTP payload. A plurality of MFUs may be stored in one MMTP payload, and conversely, one MFU may be stored in a plurality of MMTP payloads.

FIG. 7 is a diagram showing the structure of the MMTP packet.

MMTP packet consists of MMTP header and MMTP payload. Among the descriptions shown in FIG. 7, the description from the beginning to before MMTP_payload () constitutes the MMTP header.

The payload_type (payload type) included in the MMTP header indicates the data type of the MMTP payload.

FIG. 8 is a diagram showing the meaning of the value of payload_type.

As shown in FIG. 8, the value of payload_type being 0x00 indicates that the MMTP payload includes MPUs such as video and audio.

Also, the value of payload_type being 0x02 indicates that a control message is included in the MMTP payload.

Returning to the description of FIG. 7, packet_id (packet identifier) included in the MMTP header is information for identifying the data type of the MMTP payload.

NEXTVF_TR-0004 stipulates that when the MMTP payload includes an MPU (when the value of payload_type is 0x00), the asset packet_id shown in the MMT package table described later is described.

9 and 10 are diagrams showing the configuration of MMTP_payload ().

FIG. 9 shows a description when the value of payload_type is 0x00, that is, the MPU is included in the MMTP payload. On the other hand, FIG. 10 shows a description when the value of payload_type is 0x02, that is, the control message is included in the MMTP payload.

In the description shown in FIG. 9, fragment_type (fragment type) indicates the fragment type of information stored in the MMTP payload.

For example, a fragment_type value of 0 indicates that MPU metadata (FIG. 6) is included in the MMTP payload. MPU_metadata_byte in FIG. 9 described when the value of fragment_type is 0 corresponds to MPU metadata.

The value of fragment_type of 1 indicates that movie fragment metadata is included in the MMTP payload. Movie_fragment_metadata_byte of FIG. 9 described when the value of fragment_type is 1 corresponds to movie fragment metadata.

A fragment_type value of 2 indicates that the MMTP payload includes an item of sample data (NAL unit, access unit), subsample data, or timeless media data of timed media data that constitutes the MFU. . For example, MFU_data_byte in FIG. 9 described when the value of fragment_type is 2 and the value of timed_flag is 1 corresponds to the sample data of time-dependent media data constituting the MFU.

Also, in the description shown in FIG. 9, MPU_sequence_number (MPU sequence number) indicates the sequence number of the MPU to which the MMTP payload belongs when MPU metadata, movie fragment metadata, and MFU are stored.

In the description shown in FIG. 10, message_length (message data length) described when the value of payload_type is 0x02 indicates the size of one control message arranged immediately after this field in bytes.

Message_byte (message data) is the data byte of the control message. Hereinafter, the control message is also simply referred to as a message as appropriate.

<2-2. MMT control messages>
Here, the control message stored in the MMTP payload will be described.

FIG. 11 is a diagram showing the structure of the MMT-SI that is control information.

As shown in FIG. 11, the MMT-SI that indicates information related to the structure of the MMT package and the broadcasting service includes a message that stores a table and descriptor, a table that has elements and attributes indicating specific information, and details. It consists of three layers of descriptors that indicate various information.

As described above, the message is stored in the MMTP payload and transmitted using the MMTP packet. The value of payload_type when the message forms the MMTP payload is 0x02. A plurality of messages are not stored in one MMTP payload, and one message is stored in one MMTP payload.

FIG. 12 is a diagram showing the types and functions of MMT-SI messages.

As shown in FIG. 12, the message mainly includes a Package Access (PA) message, an M2 section message, a CA message, an M2 short section message, and a data transmission message. For example, the PA message becomes an entry point of MMT-SI and is used to transmit various tables of MMT-SI.

Such message type is identified by message_id (message identifier) described in the MMTP payload as message_byte.

FIG. 13 is a diagram showing the configuration of the PA message.

The message_id is set as 0x0000 as shown in FIG.

“Number_of_tables” indicates the number of tables stored in this PA message.

Table_id (table identification) indicates the identifier of the table stored in this PA message.

“Table” is a table stored by this PA message. One table, MPT (MMT package table), is described in the table () of the PA message.

The description of such a PA message is included in the MMTP payload (FIG. 10) as message_byte.

FIG. 15 is a diagram showing the configuration of the MPT.

MPT gives information that configures the package, such as asset list and asset network location. The MPT contains a descriptor.

In the description shown in FIG. 15, MPT_descriptors_length (MPT descriptor length) indicates the length of the MPT descriptor area in bytes.

MPT_descriptors_byte (MPT descriptor area) is an area for storing MPT descriptors. Examples of the descriptor stored in MPT_descriptors_byte include an MPU time stamp descriptor (MPU_Timestamp_Descriptor ()) and an MPU extended time stamp descriptor (MPU_Extended_Timestamp_Descriptor ()).

The MPU time stamp descriptor is a descriptor indicating the presentation time of the first access unit in the presentation order in the MPU. The MPU extended time stamp descriptor is a descriptor that provides the decoding time of the access unit in the MPU.

FIG. 16 is a diagram showing the structure of the MPU time stamp descriptor.

The descriptor_tag of the MPU timestamp descriptor is set as 0x001.

Mpu_sequence_number (MPU sequence number) indicates the sequence number of the MPU that describes the time stamp in the MPU time stamp descriptor. As described above, the same sequence number is added to each MPU for each MPU belonging to the same asset.

mpu_presentation_time (MPU presentation time) indicates the MPU presentation time in the NTP format (indicated by a counter value of 32 + nbit / 2 ⁿ Hz).

FIG. 17 is a diagram showing a configuration of the MPU extended time stamp descriptor.

The descriptor_tag of the MPU extended timestamp descriptor is set as 0x8026.

Mpu_sequence_number (MPU sequence number) indicates the sequence number of the MPU including the access unit that specifies the decoding time and the like in the MPU extended time stamp descriptor.

mpu_decoding_time_offset (MPU decoding time offset) is the MPU specified by the MPU sequence number, and represents the absolute value of the difference between the decoding time of the first access unit in decoding order and the presentation time of the first access unit in presentation order. It is shown in the time unit indicated on the scale.

Num_of_au (number of access units) indicates the number of access units that specify the decoding time etc. in the MPU extended time stamp descriptor.

Dts_pts_offset (decoding time / presentation time offset) indicates the time from the access unit decoding time to the presentation time in units of time indicated by a time scale.

Pts_offset (PTS offset) indicates the difference in presentation time between the immediately preceding access unit and the current access unit in the presentation order within the same MPU in units of time indicated on the time scale.

The presentation time of the first access unit in the presentation order of the MPU is specified from the MPU timestamp descriptor. Further, the decoding time of each access unit is specified from the MPU extended time stamp descriptor.

FIG. 18 is a diagram showing a calculation method of PTS and DTS in MMT.

Each rectangle shown in FIG. 18 indicates a picture (access unit) constituting GOPn included in a certain MPU. The upper part of FIG. 18 shows the arrangement of the access units in the decoding order, and the lower part shows the arrangement of the access units in the presentation order. The alphabet of I / P / B indicates the picture type, and the number indicates the number of each picture in the presentation order.

The mpu_presentation_time in the MPU timestamp descriptor indicates the presentation time of the first access unit in the presentation order in the MPU. The presentation time indicated by the MPU timestamp descriptor is the time indicated by the upward triangle at the lower left in FIG.

On the other hand, the MPU extended time stamp descriptor indicates the decoding time of the first access unit in the decoding order and the presentation of the first access unit in the presentation order in the MPU, as indicated by the dashed arrow on the left side of FIG. Indicates the difference value from the time.

Also, the MPU extended time stamp descriptor indicates the difference value between the decoding time and the presentation time of each access unit with a value that uses the time scale as a unit time by dts_pts_offest. Furthermore, the MPU extended time stamp descriptor indicates a difference value between the presentation time of the immediately preceding access unit and the presentation time of the current access unit in the presentation order in the same MPU by a value having a time scale as a unit time by pts_offset. .

Using these times and values, the decoding time DTS (n) and the presentation time PTS (n) of the nth access unit in the MPU are calculated by the following equations (1) and (2), respectively.

Thus, the PTS and DTS of each access unit are specified from the MPU time stamp descriptor and the MPU extended time stamp descriptor. Since it is obtained using mpu_presentation_time which is a counter value of 32 + nbit / 2 ⁿ Hz, it can be said that the MPU DTS is also a time indicated by a counter value of 32 + nbit / 2 ⁿ Hz.

In the information processing apparatus 1, the MPU time stamp descriptor and the MPU extended time stamp descriptor are obtained from the control message of the MMTP packet, and the PTS and DTS are obtained based on the MPU time stamp descriptor and the MPU extended time stamp descriptor. It is done. The calculation of PTS and DTS is performed before decoding of each access unit constituting the MPU transmitted using another MMTP packet.

<3. About MPEG-2 TS>
Next, MPEG-2 TS will be described.

FIG. 19 is a diagram showing a configuration of TS packets constituting the TS.

One TS packet is configured by adding a 184-byte payload, an adaptation field, or both to a 4-byte header. The header includes, for example, a PID that is identification information of the type of data included in the payload. The configuration of such a TS packet is defined in ISO / IEC 138180-1, for example.

In the adaptation field of the TS packet, PCR is included as shown by hatching in FIG. FIG. 20 is a diagram showing the configuration of the adaptation field.

At the time of conversion from MMT to MPEG-2 TS, the information processing apparatus 1 sets the PCR obtained by converting the MMT reference time represented by the time information in the NTP format in the adaptation field of the TS packet. .

FIG. 21 is a diagram showing the structure of a PES (Packetized Elementary Stream) packet.

In MPEG-2 TS, video and audio streams are divided into predetermined units and stored in PES packets. One PES packet is divided into a plurality of TS packets. A header is added to the PES packet, and PTS and DTS are described as shown in FIG.

When converting from MMT to MPEG-2 から TS, the information processing apparatus 1 sets the PTS and DTS obtained by converting the MTS PTS and DTS calculated by analyzing the MMT-SI in the PES packet. The

<4. Configuration example of information processing apparatus>
FIG. 22 is a block diagram illustrating a configuration example of the information processing apparatus 1.

The information processing apparatus 1 includes a receiving unit 31, an MMT signal processing unit 32, a recording control unit 33, a drive 34, an output control unit 35, and a communication unit 36.

The receiving unit 31 receives a broadcast wave signal from an antenna (not shown) and performs various processes such as a demodulation process and an error correction process. The receiving unit 31 outputs a TVL stream obtained by performing various processes to the MMT signal processing unit 32 as MMT content.

In addition, when the content is transmitted via a communication transmission path, the reception unit 31 controls the communication unit 36 to receive the MMT content and performs a predetermined process on the TVL stream obtained by performing predetermined processing. The signal is output to the signal processing unit 32.

The MMT signal processing unit 32 reproduces the MMT content, outputs the video and audio of the content from the television receiver, and converts the MMT content into MPEG-2 TS content.

For example, when playing back MMT content, the MMT signal processing unit 32 extracts video data and audio data from the TLV stream supplied from the receiving unit 31 and decodes them. The MMT signal processing unit 32 outputs the video and audio data of the content obtained by decoding to the output control unit 35.

Further, when converting the MMT content into the MPEG-2 TS content, the MMT signal processing unit 32 stores the data stored in the MMTP packet extracted from the TLV stream supplied from the receiving unit 31 in the TS packet. Generate TS by correcting it. The MMT signal processing unit 32 outputs the generated TS to the recording control unit 33 when recording MPEG-2 TS content on the recording medium 11, and transmits the generated TS to another device via the network 12. Is output to the communication unit 36.

The recording control unit 33 controls the drive 34 to record the TS generated by the MMT signal processing unit 32 on the recording medium 11 attached to the drive 34.

The output control unit 35 supplies the video and audio data supplied from the MMT signal processing unit 32 to, for example, a television receiver connected to the information processing apparatus 1 and outputs them from the display and the speaker, respectively.

The communication unit 36 communicates with various devices via the network 12. For example, the communication unit 36 receives MMT content distributed from the server via the network 12 and outputs the MMT content to the reception unit 31. In addition, the communication unit 36 transmits the TS generated by the MMT signal processing unit 32 to another device via the network 12.

FIG. 23 is a block diagram illustrating a configuration example of the MMT signal processing unit 32 and the recording control unit 33 in FIG.

The demultiplexer 51 extracts an IP packet from the TLV packet constituting the TLV stream supplied from the receiving unit 31, and performs a DEMUX process on the MMT data transmitted using the IP packet.

For example, the demultiplexer 51 extracts an IP packet including time information in NTP format transmitted using the TLV packet, and outputs the IP packet to the comparison unit 52. As described with reference to FIG. 5, the IP packet including the time information in the NTP format is arranged at the head of the first slot among the slots constituting the TLV stream.

Also, the demultiplexer 51 outputs the MMTP packet storing the MMT-SI among the MMTP packets transmitted using the IP packet to the MMT-SI analysis unit 55. The demultiplexer 51 outputs the MMTP packet storing the video data and the audio data constituting the MPU to the MPU / MMT packet analysis unit 58. The type of data stored in the MMTP payload is identified by the payload_type of the MMTP packet (FIG. 8).

The comparison unit 52 outputs the reference time (32 + nbit counter value) included in the NTP format time information stored in the IP packet supplied from the demultiplexer 51 to the NTP clock counter 53 and sets it as the initial value of the counter value. .

Further, the comparison unit 52 outputs a signal representing an error between the time information from the NTP clock counter 53 and the time information in the NTP format supplied from the demultiplexer 51 to the NTP clock counter 53.

The NTP clock counter 53 has a VCO (Voltage Controlled Oscillator). NTP clock counter53 counts the clock signal of 2 ⁿ Hz of VCO generates and outputs a system clock signal of 2 ⁿ Hz representing a counter value of 32 + nbit. The system clock signal output from the NTP clock counter 53 is supplied to the comparison unit 52, clock conversion unit 54, and video / audio synchronization control unit 56.

The clock conversion unit 54 converts the 32 + n bit counter value represented by the 2 ⁿ Hz system clock signal supplied from the NTP clock counter 53 into a 42 bit counter value (27 MHz) indicating MPEG-2 TS PCR. Details of the conversion by the clock conversion unit 54 will be described later. The clock conversion unit 54 outputs the 42-bit counter value obtained by the conversion to the TS conversion processing unit 62 as PCR.

The MMT-SI analysis unit 55 acquires and analyzes the MMT-SI from the MMTP packet stored in the IP packet supplied from the demultiplexer 51. For example, the MMT-SI analysis unit 55 acquires the MPT transmitted by the PA message stored in the MMTP packet, and the MPU time stamp descriptor (FIG. 16) and the MPU extended time stamp descriptor (FIG. 16) described in the MPT. 17) is acquired.

In addition, the MMT-SI analysis unit 55 calculates (identifies) the PTS of each MPU based on the MPU time stamp descriptor. The MMT-SI analyzing unit 55 uses the PTS of each MPU and the description of the MPU extended time stamp descriptor as described with reference to FIG. 18 to calculate the DTS of the access unit constituting each MPU. .

The MMT-SI analysis unit 55 outputs the calculated PTS and DTS to the video / audio synchronization control unit 56 and the PTS / DTS conversion unit 57 together with mpu_sequence_number indicating the sequence number of the MPU. As described above, mpu_sequence_number included in the MPU time stamp descriptor indicates the sequence number of the MPU that designates the presentation time (FIG. 16). Further, mpu_sequence_number included in the MPU extended time stamp descriptor indicates the sequence number of the MPU including the access unit that specifies the decoding time or the like (FIG. 17).

The video / audio synchronization control unit 56 operates in accordance with the system clock signal from the NTP / clock / counter 53, and controls the decoding and output timing of the video / audio decoder 60 based on the PTS and DTS calculated by the MMT-SI analysis unit 55. . The video / audio decoder 60 is controlled by the video / audio synchronization control unit 56 based on metadata such as MPU metadata and movie fragment metadata supplied from the MPU / MMT packet analysis unit 58.

The PTS / DTS conversion unit 57 converts the 32 + nbit counter values representing the PTS and DTS calculated by the MMT-SI analysis unit 55 into the counter values (90 kHz) representing the MPEG-2 TS 33-bit PTS and DTS, respectively. To do. Details of the conversion by the PTS / DTS converter 57 will be described later. The PTS / DTS conversion unit 57 outputs the MPEG-2DTS PTS and DTS obtained by the conversion to the TS conversion processing unit 62.

The PTS / DTS conversion unit 57 outputs mpu_sequence_number representing the sequence number of the MPU related to the PTS and DTS of the MPEG-2 TS obtained by the conversion. Also, in the PTS / DTS conversion unit 57, an SI that needs to be included in the MPEG-2 TS is appropriately generated based on the MMT-SI and output to the TS conversion processing unit 62.

The MPU / MMT packet analysis unit 58 analyzes the MMTP packet stored in the IP packet supplied from the demultiplexer 51, thereby acquiring the data of each MPU. The MPU metadata, movie fragment metadata, and MFU that are data of each MPU are specified by MPU_sequence_number (FIG. 9) that is information indicating the sequence number of the MPU to which they belong.

The MPU / MMT packet analysis unit 58 outputs MPU metadata and movie fragment metadata, etc., of each MPU acquired from the MMTP payload to the video / audio synchronization control unit 56 when the MMT content is played back. In addition, the MPU / MMT packet analysis unit 58 outputs the video data and audio data of the MFU constituting each MPU acquired from the MMTP payload to the decoder buffer 59.

On the other hand, the MPU / MMT packet analysis unit 58 converts the video data (VIDEO ES) and audio data (AUDIO ES) of the MFUs that make up each MPU obtained from the MMTP payload when converting the format from MMT to MPEG-2 TS. Output to buffer 61 together with MPU_sequence_number.

The video / audio decoder 60 decodes and outputs the video data and audio data recorded in the decoder buffer 59 in accordance with the control by the video / audio synchronization control unit 56. The data output from the video / audio decoder 60 is supplied to the output control unit 35, and the video and audio of the content are output.

The TS processing unit 62 configures a PES by collecting data set with the same value as the MPU_sequence_number among the video data and audio data recorded in the buffer 61. Further, the TS processing unit 62 adds the PTS and DTS related to each PES supplied from the PTS / DTS conversion unit 57 to each PES, and generates a PES packet. The PES to which each PTS / DTS is added is specified based on mpu_sequence_number supplied from the PTS / DTS conversion unit 57.

The TS processing unit 62 converts the generated PES packet into a TS packet. The TS conversion processing unit 62 generates a TS based on the TS packet in which the data of the PES packet is stored in the payload, and the TS packet including the PCR generated by the clock conversion unit 54 in the adaptation field.

When generating a Partial TS, the TS processing unit 62 supplies MPEG-2 TS SI such as PAT, PMT, DAT, and SIT specified by ARIB STD-B14 to the information supplied from the PTS / DTS converter 57. Embed in TS based on

PAT (Program Association Table) is information that specifies a packet identifier of a TS packet that transmits a PMT related to a Partial TS. PMT (Program Map) is information that specifies a packet identifier of a TS packet that transmits each encoded signal constituting a broadcast program. PAT and PMT are retransmitted once every 100 ms.

DIT (Discontinuity Information Table) is information indicating a change point where program arrangement information of a program transmitted by Partial TS may be discontinuous. SIT (Selection Information Table) is information indicating information related to a program transmitted in Partial TS.

The TS processing unit 62 outputs the TS obtained by performing the above TS processing to the recording control unit 33.

The recording control unit 33 includes a T-STD 81, a PLL 82, an arrival time clock counter 83, a source packetizer 84, and a write buffer 85. Note that the configuration of the recording control unit 33 shown in FIG. 23 is a conceptual model for defining the recording process. The recording control unit 33 has a function of adding an ATS (Arrival_time_stamp) to the TS packets constituting the TS and generating a sequence of source packets according to the recorder model.

The i-th byte of TS supplied from the MMT signal processing unit 32 is input to a T-STD (Transport stream target decoder) 81 and Source packetizer 84 at time t (i).

The T-STD 81 is a virtual decoder in the recorder model. A decoder corresponding to the T-STD 81 does not exist in the recording control unit 33.

The PLL 82 generates a 27 MHz clock locked to the TS PCR value.

The arrival time clock counter 83 is a binary counter that counts the 27 MHz frequency pulses output from the PLL 82. Arrival_time_clock (i) is a counter value of Arrival time clock counter 83 at time t (i).

Source packetizer 84 adds TP_extra_header to all TS packets and generates source packets. The Source packetizer 84 adds an ATS to the TS packet.

Specifically, the source packetizer 84 sets the ATS value in the TP_extra_header of the source packet based on Arrival_time_clock (i) supplied from the Arrival time clock counter 83. ATS represents the time at which the first byte of the TS packet arrives at both T-STD 81 and Source packetizer 84.

Write Buffer 85 records the source packet generated by Source packetizer 84. Each source packet output from the Write buffer 85 is supplied to the drive 34 and recorded on the recording medium 11.

<5. Counter value conversion>
<5-1. PTS / DTS conversion of PTS / DTS converter 57>
Here, conversion of a counter value indicating PTS / DTS will be described.

FIG. 24 is a diagram showing the relationship between the counter value and time in MPEG-2 TS.

The horizontal axis of the graph shown in FIG. 24 indicates time, and the vertical axis indicates counter value. The same applies to FIGS. 25 and 26.

* PTS / DTS of MPEG-2 TS is expressed based on PCR. PCR is represented by 42 bits (27 MHz), and PTS / DTS is represented by 33 bits (90 kHz). Since PTS / DTS is represented by 33 bits, 33 bits is sufficient as the amount of information for representing time information.

When operating a 33bit counter 90kHz precision, the counter value of the wraparound (wrap around-) occurs at time point P1 which counter value is 2 ^33. The time of the point P1 is calculated as approximately 26.5h as shown in the following expression (3).

The second wraparound occurs at the time point P2, and the third wraparound occurs at the time point P3. The relationship between the count value of the 33-bit counter with 90 kHz accuracy and the real time is as shown in FIG. 24 in which a wraparound occurs at the times of points P1, P2, and P3.

It should be noted that the straight line connecting the origin and the point P11 shows the relationship between the real time and the counter value when a 42-bit counter that is the same as the number of bits of PCR is operated with an accuracy of 90 kHz.

FIG. 25 is a diagram showing the relationship between the counter value in MMT and time.

As described above, PTS / DTS of MMT, respectively, 32 + nbit by NTP format (1 second or less precision 2 ⁿ Hz) represented by.

When the 32 + nbit counter is operated with an accuracy of 2 ⁿ Hz, the wraparound of the counter value occurs at the time point P21 at which the counter value becomes 2 ^{32 + n} . The time of the point P21 is represented as 1193046h as shown in the following formula (4).

The relationship between the counter value of the 32 + nbit counter with an accuracy of 2 ⁿ Hz and the real time is indicated by a one-dot chain line in which a wraparound occurs at the time point P21.

FIG. 26 is a diagram showing the characteristics of the MPEG-2 TS 33-bit counter and the characteristics of the MMT 32 + nbit counter in an overlapping manner.

When the MTS PTS / DTS indicates a predetermined time T, the corresponding MPEG-2 TS PTS / DTS obtains the counter value of the 33-bit counter representing the time T based on the counter value of the 32 + nbit counter. Is specified by

More specifically, the MPEG-2’TS counter value X ′ is obtained by the following procedure based on the MMT counter value X.

・ Procedure 1
An MMT counter value A at the wraparound time in MPEG-2 TS is obtained.

The MMT counter value A is a value corresponding to a time of 2 ³³ / 90k (≈26.5h) in real time. When n = 24, the counter value A is obtained as shown in the following equation (5).

・ Procedure 2
The MPEG-2 TS counter value X ′ indicating the same time as that indicated by the MMT counter value X is obtained by the following equation (6) when the time indicated by the MMT counter value X is smaller than 26.5h. It is done.

On the other hand, when the time indicated by the MMT counter value X is greater than 26.5h, the MPEG-2 TS counter value X ′ is calculated using the remainder mod (X / A) value as the MMT counter value X. It is calculated | required like Formula (7).

The PTS / DTS converter 57 in FIG. 23 thus compares the ratio between the real time and the counter value in the characteristics of the MMT 32 + nbit counter and the ratio between the real time and the counter value in the characteristics of the 33 bit counter of the MPEG-2 TS. Is used to convert the counter value.

For example, when the time indicated by the MMT counter value X is smaller than 26.5h, the relationship of the following equation (8) is derived from the characteristics of the MMT 32 + nbit counter, and from the characteristics of the MPEG-2 TS 33bit counter: The relationship of the following formula (9) is derived.

T1 in Expressions (8) and (9) is a time when the MMT counter value is X and the MPEG-2 TS counter value is X ′.

The PTS / DTS converter 57 substitutes the value of the MMT PTS / DTS as the value of X in Equations (8) and (9), and obtains the counter value X ′ by the same calculation as in Equation (6) above. It will be. Even if n is a value other than 24, the counter value can be converted in the same manner.

<5-2. Clock conversion of clock converter 54>
Next, the conversion of the counter value representing the reference time will be described.

In MMT, the reference time included in the time information in the NTP format is expressed as a counter value of 32 + n bits.

The clock conversion unit 54 converts the 32 + nbit counter value as the counter value of the 33-bit counter with 90 kHz accuracy as described with reference to FIG.

Further, the clock conversion unit 54 adds the counter value of the 9-bit counter with 27 MHz accuracy to the LSB side of the 33-bit counter value obtained by the conversion, so that the 27 MHz accuracy of the configuration shown in FIG. 42-bit counter value is generated. In FIG. 27, the right side is the LSB side.

The 9-bit counter with 27 MHz accuracy is a counter that the clock conversion unit 54 has as a free-running free-run counter, for example. The upper limit of the counter value of the 9-bit counter is set to take a value in the range of 0 to 300.

The clock conversion unit 54 outputs the 42-bit counter value generated in this way to the TS processing unit 62 as PCR. PCR is expressed as ³³ bits (90 kHz counter 0 to (2 ³³ -1)) + 9 bits (27 MHz counter 0 to 300).

<6. Operation of information processing apparatus>
Next, a series of processes of the information processing apparatus 1 that converts MMT content into MPEG-2 TS content and records the content on the recording medium 11 will be described with reference to the flowchart in FIG.

In step S1, the receiving unit 31 acquires MMT content supplied via a broadcast wave transmission path or a communication transmission path. The receiving unit 31 outputs a TVL stream, which is MMT content data, to the MMT signal processing unit 32.

In step S2, the demultiplexer 51 of the MMT signal processing unit 32 extracts the IP packet from the TLV packet constituting the TLV stream, and performs the DEMUX process. That is, an IP packet including time information in the NTP format is supplied to the comparison unit 52, and an MMTP packet storing MMT-SI is supplied to the MMT-SI analysis unit 55. The MMTP packet storing the video data and audio data constituting the MPU is supplied to the MPU / MMT packet analysis unit 58.

In step S3, the MPU / MMT packet analysis unit 58 extracts the video data and audio data of the MFU constituting each MPU from the MMTP packet. The extracted video data and audio data are output to the buffer 61 and stored together with MPU_sequence_number.

In step S4, the comparison unit 52 sets the initial value of the NTP clock counter 53 based on the reference time (32 + nbit counter value) included in the time information in the NTP format.

In step S5, the NTP clock counter 53 outputs a system clock signal representing a counter value of 32 + n bits.

In step S6, the clock conversion unit 54 converts the 32 + nbit counter value represented by the 2 ⁿ Hz system clock signal supplied from the NTP clock counter 53 into a 42-bit counter value indicating the MPEG-2 TS PCR. The 42-bit counter value obtained by the conversion is supplied to the TS conversion processing unit 62 as PCR.

In step S7, the MMT-SI analysis unit 55 analyzes the MMT-SI stored in the MMTP packet to acquire the MPU time stamp descriptor and the MPU extended time stamp descriptor, and the PTS and MPU of each MPU. The DTS of the access unit that constitutes is calculated.

In step S8, the PTS / DTS conversion unit 57 converts the 32 + nbit counter values representing the PTS and DTS calculated by the MMT-SI analysis unit 55 into the counter values representing the 33bit PTS and DTS of MPEG-2MTS, respectively. Convert.

In step S9, the TS processing unit 62 configures a PES using video data and audio data in which the same value is set as MPU_sequence_number, and generates a PES packet by adding a PTS and a DTS related to each PES. .

In step S10, the TS processing unit 62 converts the PES packet into a TS packet.

In step S11, the TS processing unit 62 inserts a TS packet including the PCR generated by the clock conversion unit 54 in the adaptation field into the TS packet in which the data of the PES packet is stored in the payload, thereby generating a TS. . As appropriate, a TS packet storing SI generated based on MMT-SI is also inserted into the TS.

In step S12, the recording control unit 33 controls the drive 34 to record the TS generated by the MMT signal processing unit 32 on the recording medium 11.

By the above processing, MMT content with different time axis can be converted to MPEG-2 TS content and recorded on a recording medium such as BD.

<7. Modification>
<7-1. About reverse transformation>
In the above description, the case where the MMT content is converted into the MPEG-2 TS content has been described. However, the MPEG-2 TS content can be converted into the MMT content.

In this case, the information processing apparatus 1 acquires video data and audio data from the TS packet constituting the TS of the MPEG-2 TS content to be converted, and stores it again in the MMTP packet.

In addition, the information processing apparatus 1 extracts the PCR represented as a 42-bit counter value from the TS packet and converts it into a reference time in the NTP format represented as a 32 + n-bit counter value.

Further, the information processing apparatus 1 extracts PTS / DTS (90 kHz) of MPEG-2） TS expressed as a 33-bit counter value from the PES packet, and converts it to PTS / DTS of MMT expressed as a 32 + n-bit counter value. .

The information processing apparatus 1 generates an MMTP packet that stores a control message that transmits an MMTP packet that stores video data and audio data, and a descriptor that is used to calculate the PTS / DTS of the MMT. Further, the information processing apparatus 1 generates a TLV stream by multiplexing the generated IP packet storing the MMTP packet and the IP packet including time information in the NTP format.

Here, PTS / DTS reverse conversion and reference time reverse conversion are performed as follows.

That is, the MMT counter value X is obtained by the following procedure based on the MPEG-2 TS counter value X ′.

The MMT counter value A is a value corresponding to a time of 2 ³³ / 90k (≈26.5h) in real time. When n = 24, the counter value A is obtained as shown in the above equation (5).

The process in step 1 is the same as the process for converting MMT content to MPEG-2 TS content.

・ Procedure 2
The MMT counter value X indicating the same time as the time indicated by the MPEG-2 TS counter value X ′ is equal to the following formula (10) when the time indicated by the MPEG-2 TS counter value X ′ is smaller than 26.5 h. It is required as follows.

On the other hand, when the time indicated by the MPEG-2 TS counter value X ′ is greater than 26.5 h, the MMT counter value X is set to the remainder mod (X ′ / A) as the MPEG-2 TS counter value X ′. And obtained as shown in the following equation (11).

MPEG-2 TS PTS / DTS is converted to MMT PTS / DTS by such reverse conversion processing. Further, in the MPEG-2 TS PCR having the configuration of FIG. 27, the 33-bit counter value on the MSB side is converted into a 32 + n-bit counter value by such an inverse conversion process, and used as a reference time.

Note that, from this procedure, it can be converted only to a counter value of A or less, but it is also possible to convert to a counter value of A or more by using an internal counter and appropriately adding the counter value.

<7-2. Other examples>
In the above, the conversion from MMT to MPEG-2 TS and the reverse conversion from MPEG-2 TS to MMT have been described. However, the format of the content to be converted / inverted is limited to MMT and MPEG-2 TS. It is not a thing. The above-described processing can be used for conversion / inversion of various formats with different time axes.

Although the content to be converted / inverted includes both video data and audio data, the above-described processing may be applied to the conversion / inverse conversion of the format of one of the contents. . Further, the present invention may be applied to format conversion / inverse conversion of types of data other than video data and audio data.

Configuration Example of Computer The series of processes described above can be executed by hardware or can be executed by software. When a series of processing is executed by software, a program constituting the software is installed from a program recording medium into a computer incorporated in dedicated hardware or a general-purpose personal computer.

FIG. 29 is a block diagram showing an example of the hardware configuration of a computer that executes the above-described series of processing by a program.

A CPU (Central Processing Unit) 1001, ROM (Read Only Memory) 1002, and RAM (Random Access Memory) 1003 are connected to each other via a bus 1004.

Further, an input / output interface 1005 is connected to the bus 1004. The input / output interface 1005 is connected to an input unit 1006 including a keyboard and a mouse, and an output unit 1007 including a display and a speaker. The input / output interface 1005 is connected to a storage unit 1008 made up of a hard disk, a non-volatile memory, etc., a communication unit 1009 made up of a network interface, etc., and a drive 1010 that drives a removable medium 1011.

In the computer configured as described above, for example, the CPU 1001 loads the program stored in the storage unit 1008 to the RAM 1003 via the input / output interface 1005 and the bus 1004 and executes it, thereby executing the above-described series of processing. Is done.

The program executed by the CPU 1001 is recorded in the removable medium 1011 or provided via a wired or wireless transmission medium such as a local area network, the Internet, or digital broadcasting, and installed in the storage unit 1008.

The program executed by the computer may be a program that is processed in time series in the order described in this specification, or in parallel or at a necessary timing such as when a call is made. It may be a program for processing.

Embodiments of the present technology are not limited to the above-described embodiments, and various modifications can be made without departing from the gist of the present technology.

For example, the present technology can take a cloud computing configuration in which one function is shared by a plurality of devices via a network and is jointly processed.

Further, each step described in the above flowchart can be executed by one device or can be shared by a plurality of devices.

Further, when a plurality of processes are included in one step, the plurality of processes included in the one step can be executed by being shared by a plurality of apparatuses in addition to being executed by one apparatus.

-Example of combination of configurations The present technology may have the following configurations.
(1)
A receiving unit for receiving first multiplexed data obtained by multiplexing data including a video stream and an audio stream in a first format;
The first counter value of the number of bits specified by the first format, which is included as time information in the first multiplexed data, is converted to the second counter value of the number of bits specified by the second format. A conversion unit;
The video data constituting the video stream and the audio data constituting the audio stream are respectively stored in packets of the second format, and the second counter value of the second format includes the second counter value as time information. An information processing apparatus comprising: a multiplexing unit that generates the multiplexed data.
(2)
The first format is MMT;
The information processing apparatus according to (1), wherein the second format is MPEG-2 TS.
(3)
The first counter value representing the reference time is a 32 + n-bit time in which the time in seconds of 1 second or more is represented by 32 bits, and the precision of 1 second or less is 2 ⁿ Hz (n is an integer of 24 or more). Counter value,
The second counter value representing the reference time is a 42-bit counter value that represents a time of 1 second or more in 33 bits with an accuracy of 90 kHz, and a time of 1 second or less in 9 bits with an accuracy of 27 MHz. The information processing apparatus according to (2).
(4)
The multiplexing unit adds a TS packet including PCR as the second counter value indicating a reference time to a TS packet storing the video data and a TS packet storing the audio data, and The information processing apparatus according to (3), wherein the multiplexed data of 2 is generated.
(5)
The first counter value representing the presentation time and the first counter value representing the decoding time are 32 + n bits where the time in seconds of 1 second or more is represented by 32 bits, and the accuracy of 1 second or less is 2 ⁿ Hz Counter value of
The information processing apparatus according to (3) or (4), wherein the second counter value representing presentation time and the second counter value representing decoding time are counter values represented in 33 bits with an accuracy of 90 kHz.
(6)
The multiplexing unit includes a TS packet that stores the video data and a PES packet that is a source of the TS packet that stores the audio data, and the PTS as the second counter value that represents the presentation time and the decoding time that represents the decoding time. The information processing apparatus according to (5), wherein a DTS as a second counter value is added.
(7)
The information processing apparatus according to (6), wherein the multiplexing unit generates a PES packet including the video data and the audio data belonging to the same MPU based on an MPU sequence number.
(8)
The information processing apparatus according to any one of (2) to (7), further including a recording control unit configured to record a TS as the second multiplexed data on a recording medium.
(9)
The information processing apparatus according to (8), wherein the recording medium is a Blu-ray (registered trademark) Disc.
(10)
Receiving first multiplexed data obtained by multiplexing data including a video stream and an audio stream in a first format;
The first counter value of the number of bits specified by the first format, which is included as time information in the first multiplexed data, is converted into a second counter value of the number of bits specified by the second format. ,
The video data constituting the video stream and the audio data constituting the audio stream are respectively stored in packets of the second format, and the second counter value of the second format includes the second counter value as time information. An information processing method including a step of generating multiplexed data.
(11)
Receiving first multiplexed data obtained by multiplexing data including a video stream and an audio stream in a first format;
The first counter value of the number of bits specified by the first format, which is included as time information in the first multiplexed data, is converted into a second counter value of the number of bits specified by the second format. ,
The video data constituting the video stream and the audio data constituting the audio stream are respectively stored in packets of the second format, and the second counter value of the second format includes the second counter value as time information. A program for causing a computer to execute a process including a step of generating multiplexed data.

1 Information processing device, 11 recording medium, 32 MMT signal processing unit, 33 recording control unit, 51 demultiplexer, 52 comparison unit, 53 NTP clock counter, 54 clock conversion unit, 55 MMT-SI analysis unit, 56 video / audio synchronization control Section, 57 PTS / DTS conversion section, 58 MPU / MMT packet analysis section, 59 decoder buffer, 60 video / audio decoder, 61 buffer, 62 TS processing section

Claims

A receiving unit for receiving first multiplexed data obtained by multiplexing data including a video stream and an audio stream in a first format;
The first counter value of the number of bits specified by the first format, which is included as time information in the first multiplexed data, is converted to the second counter value of the number of bits specified by the second format. A conversion unit;
The video data constituting the video stream and the audio data constituting the audio stream are respectively stored in packets of the second format, and the second counter value of the second format includes the second counter value as time information. An information processing apparatus comprising: a multiplexing unit that generates the multiplexed data.
The first format is MMT;
The information processing apparatus according to claim 1, wherein the second format is MPEG-2 TS.
The first counter value representing the reference time is a 32 + n-bit time in which the time in seconds of 1 second or more is represented by 32 bits, and the precision of 1 second or less is 2 n Hz (n is an integer of 24 or more). Counter value,
The second counter value representing the reference time is a 42-bit counter value that represents a time of 1 second or more in 33 bits with an accuracy of 90 kHz, and a time of 1 second or less in 9 bits with an accuracy of 27 MHz. The information processing apparatus according to claim 2.
The multiplexing unit adds a TS packet including PCR as the second counter value indicating a reference time to a TS packet storing the video data and a TS packet storing the audio data, and The information processing apparatus according to claim 3, wherein two pieces of multiplexed data are generated.
The first counter value representing the presentation time and the first counter value representing the decoding time are 32 + n bits where the time in seconds of 1 second or more is represented by 32 bits, and the accuracy of 1 second or less is 2 n Hz Counter value of
The information processing apparatus according to claim 3, wherein the second counter value representing presentation time and the second counter value representing decoding time are counter values represented in 33 bits with an accuracy of 90 kHz.
The multiplexing unit includes a TS packet that stores the video data and a PES packet that is a source of the TS packet that stores the audio data, and the PTS serving as the second counter value indicating the presentation time and the decoding time The information processing apparatus according to claim 5, wherein a DTS as a second counter value is added.
The information processing apparatus according to claim 6, wherein the multiplexing unit generates a PES packet including the video data and the audio data belonging to the same MPU based on an MPU sequence number.
The information processing apparatus according to claim 2, further comprising: a recording control unit that records the TS as the second multiplexed data on a recording medium.
The information processing apparatus according to claim 8, wherein the recording medium is a Blu-ray (registered trademark) Disc.
Receiving first multiplexed data obtained by multiplexing data including a video stream and an audio stream in a first format;
The first counter value of the number of bits specified by the first format, which is included as time information in the first multiplexed data, is converted into a second counter value of the number of bits specified by the second format. ,
The video data constituting the video stream and the audio data constituting the audio stream are respectively stored in packets of the second format, and the second counter value of the second format includes the second counter value as time information. An information processing method including a step of generating multiplexed data.
Receiving first multiplexed data obtained by multiplexing data including a video stream and an audio stream in a first format;
The first counter value of the number of bits specified by the first format, which is included as time information in the first multiplexed data, is converted into a second counter value of the number of bits specified by the second format. ,
The video data constituting the video stream and the audio data constituting the audio stream are respectively stored in packets of the second format, and the second counter value of the second format includes the second counter value as time information. A program for causing a computer to execute a process including a step of generating multiplexed data.