KR102466262B1 - Transmission protocol conversion method and system based on broadcasting system - Google Patents

Abstract

The present invention provides a transport protocol conversion method and system based on a broadcasting system, wherein the system encapsulates a media resource into a first protocol packet according to a first protocol, and converts the first protocol packet into a packet, It involves obtaining a TS packet for transmission. The present invention can utilize an existing infrastructure when implementing a new network protocol such as MMT in a broadcast network, thereby providing richer and more diverse media services at a relatively low cost.

Description

Transmission protocol conversion method and system based on broadcasting system

This application claims priority to the Chinese patent with an application date of July 11, 2018, and an application number of CN201810758261.8.

The present invention relates to the field of multimedia transmission, and more particularly, to a transmission protocol conversion method and system based on a broadcast system.

From the analog TV era to the digital TV era, the existing broadcast TV service has a huge media market as it has been well received by public users for its rich content, high-definition video, and high smoothness. In contrast, the Internet, particularly mobile Internet digital media services, has developed rapidly and has become popular due to the advantages of sharing, openness and interaction. In recent years, digital media, especially new media services represented by online video and mobile video, have become a major growth point of information consumption. The development of the Internet and mobile Internet has brought serious challenges to the existing broadcast TV industry and good development opportunities at the same time.

With the development of media network technology, today's broadcasting industry has created more open and rich entertainment resources, and organically integrating shared information and personalized content is a research topic. Due to the widespread application of home digital media systems, the traditional single device, single content consumption such as TVs and computers can no longer meet people's home entertainment consumption needs. Specifically, in terms of media consumption, the current mass media content provides users with more consumption options, but due to the sloppy associations and organizational relationships between the contents, there is a serious information gap when users consume. In the case of video media content, the problem is particularly serious because there is no effective content description mechanism due to the dynamically time-varying nature of video content. Providing a personalized, intelligent and socialized consumption experience is another challenge for broadcasting to adapt to future media applications. The contradiction of limits is highlighted, and the technology of synchronizing and combining multi-terminal media content is desperately needed to reach a more complete consumer experience for users.

New media transmission technology, characterized by smart processing of media content, smart distribution of media networks, terminal bonding and resonant consumption, etc., has become a research topic in academia, standards and industry in recent years. Internationally, the MPEG (Moving Picture Experts Group) standards organization has established the MPEG Media Transport (MMT) protocol. In China, a standard working group for digital audio and video codec technology has also established a corresponding standard, the Smart Media Transport (SMT) protocol. The first protocol and the SMT protocol are both application layer transport protocols oriented to packet exchange, and both support technologies such as multi-network convergence and multi-screen interaction, and provide excellent solutions to solve the above problems, while at the same time providing an excellent solution to the existing TV service area has also been expanded. These protocols can form a new system of next-generation media content services by providing smart, diversified, and personalized media services.

In terms of media content distribution, broadcasting is still a very important content delivery method. MPEG-2's transport stream (TS) provides sufficient flexibility for multiplexing technology, and the TS stream uses a packet structure of a fixed length. , the receiver can restore synchronization by detecting synchronization information of a subsequent packet at a fixed position. Since MPEG-2 TS is widely applied in the broadcasting field due to excellent interference prevention, adaptability to channel environment, and low receiver cost, many existing infrastructures are based on TS streams. As described above, a broadcast service based on a simple TS stream cannot satisfy consumer demand. At this stage, when realizing a new media transmission technology represented by the first protocol, how to use the existing broadcasting equipment has become a problem that must be solved.

For the disadvantages of the prior art, an object of the present invention is to provide a transmission protocol conversion method and system based on a broadcast system.

A transport protocol conversion method based on a broadcasting system provided by the present invention,

an initial encapsulation step of encapsulating the media resource into a first protocol packet according to the first protocol;

and packet-converting the first protocol packet to obtain a TS packet for network transmission.

Preferably, the packet conversion step comprises:

ULE encapsulation sub-step of obtaining a ULE packet by ULE-encapsulating the first protocol packet;

TS encapsulation sub-step of obtaining a TS packet by TS encapsulating the ULE packet.

Preferably, the packet structure of the ULE packet includes an HDR segment, a first protocol data segment, and a CRC segment,

The first protocol data segment is a ULE packet load, that is, a first protocol packet,

The CRC segment is a cyclic redundancy check code, which is 32 bits,

The HDR segment is

Length: 16 bits, indicating the byte length of the first protocol packet encapsulated in the ULE;

Type: 16 bits, indicating the type of the first protocol packet; includes

Preferably, the TS packet includes a packet header and a load segment,

The packet header is

Sync Byte: 8 bits;

Error code indication: 1 bit, set to “1” if there is an uncorrectable bit error in the TS packet;

Unit start indication: 1 bit, set to "1" if the load segment is the first data segment after splitting the ULE packet;

Priority: 1 bit, in packets with the same PID, set to “1” if the priority is higher;

PID: 13 bits, corresponding to the first protocol packet;

Scrambling Control: 2 bits, indicating the scrambling method of the load;

AF control: 2 bits, indicating whether the packet header adaptation field is included after the packet header;

Consecutive counter: 4 bits, incremented with packets with the same PID; includes

Preferably,

The method further includes a decapsulation step of obtaining a first protocol packet by performing packet conversion mutually with the packet conversion step on the received TS packet.

A transport protocol conversion system based on the broadcasting system provided by the present invention,

an initial encapsulation module for encapsulating a media resource into a first protocol packet according to a first protocol;

a packet conversion module for packet-converting the first protocol packet to obtain a TS packet for network transmission; includes

Preferably, the packet conversion module comprises:

a ULE encapsulation sub-module for obtaining a ULE packet by ULE-encapsulating the first protocol packet;

and a TS encapsulation sub-module that TS encapsulates the ULE packet to obtain a TS packet.

Preferably, the packet structure of the ULE packet includes an HDR segment, a first protocol data segment, and a CRC segment,

The first protocol data segment is a ULE packet load, that is, a first protocol packet,

The CRC segment is a cyclic redundancy check code, which is 32 bits,

The HDR segment is

Length: 16 bits, indicating the byte length of the first protocol packet encapsulated in the ULE;

type: 16 bits, indicating the type of the first protocol packet;

Preferably, the TS packet includes a packet header and a load segment,

The packet header is

Sync Byte: 8 bits;

Error code indication: 1 bit, set to “1” if there is an uncorrectable bit error in the TS packet;

Unit start indication: 1 bit, set to "1" if the load segment is the first data segment after splitting the ULE packet;

Priority: 1 bit, in packets with the same PID, set to “1” if the priority is higher;

PID: 13 bits, corresponding to the first protocol packet;

Scrambling Control: 2 bits, indicating the scrambling method of the load;

AF control: 2 bits, indicating whether the packet header adaptation field is included after the packet header;

Consecutive counter: 4 bits, incremented with packets with the same PID; includes

Preferably,

It further includes; a decapsulation module for mutually converting the received TS packet with the packet conversion module to obtain a first protocol packet.

Compared with the prior art, the present invention has the following advantageous effects:

The present invention can utilize an existing infrastructure when implementing a new network protocol such as MMT in a broadcast network, thereby providing richer and more diverse media services at a relatively low cost.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Non-limiting embodiments will be described in detail below with reference to the drawings, through which other features, objects and advantages of the present invention will become more apparent.
1 is a frame diagram of a system of an embodiment of the present invention;
2 is a schematic diagram of conversion from an MMTP packet to a TS packet according to an embodiment of the present invention.
3 is a structural schematic diagram of a ULE packet.
4 is a structural schematic diagram of a TS packet.

Hereinafter, the present invention will be described in detail by combining specific examples. The following examples will help those skilled in the art to further understand the present invention, but do not limit the present invention in any way. It should be noted that a person skilled in the art may further make several modifications and improvements without departing from the configuration of the present invention, which falls within the protection scope of the present invention.

This embodiment will be described using the MMT protocol as the first protocol as an example, but the present invention is not limited thereto.

1 and 2, the transport protocol conversion method based on the broadcast system provided by the present invention is,

an initial encapsulation step of encapsulating the media resource into a first protocol packet according to the first protocol;

and packet-converting the first protocol packet to obtain a TS packet for network transmission.

The media resources of the server are encapsulated in MMTP packets according to the MMT protocol, and after packet conversion, TS packets that can be adapted to the existing broadcasting infrastructure are output, and the network (broadband network, cellular network, broadcasting network, etc.) is sent to the receiving end. are sent If the receiver performs packet conversion with the transmitter again, an encapsulated MMTP packet can be obtained based on the MMT protocol, providing a richer, more flexible and personalized media service.

The MMTP packet of this embodiment is generated by being encapsulated according to the MMT protocol standard, and then ULE (Unidirectional Lightweight Encapsulation) encapsulation and TS encapsulation are sequentially performed to complete MMT-TS packet conversion. The TS packet obtained after conversion is sent to the receiving end through the broadcast network, and when the receiving end decapsulates the packet, the TS-MMT packet conversion can be completed. Hereinafter, a specific embodiment of MMT-TS packet conversion of the transmitting end is introduced, and the TS-MMT packet conversion step of the receiving end is opposite to the MMT-TS packet conversion of the transmitting end, that is, TS decapsulation is performed first, and then ULE decapsulation is performed. Encapsulation proceeds to obtain the first MMTP packet.

ULE encapsulation:

Media resources after fragmentation and encapsulation according to the MMT protocol can be transmitted in various networks such as broadband networks, cellular networks, and broadcasting networks after being packed into MMTP packets. do. Since MMT encapsulation has advantages such as flexibility and support for heterogeneous networks and personalized scenarios, the present invention does not change the standard MMT encapsulation format, performs packet conversion in terms of MMTP packets, and finally converts them into TS packets.

As shown in FIG. 1 , the MMTP packet is encapsulated twice in total during packet conversion. First, we proceed with ULE encapsulation of light weight (which can be ULE or MLE). The encapsulated ULE packet structure is as shown in FIG. 3, and for the grammar format, refer to Table 1.

The relevant fields have the following meanings:

mmtp_length: 16 bits, indicating the byte length of the MMTP data packet encapsulated in the ULE;

mmtp_type (type): 16-bit, indicating the type of MMTP packet;

MMTP_data (data): ULE packet load, that is, MMTP packet;

CRC: Cyclic Redundancy Check, 32-bit, used to detect data transmission errors.

TS encapsulation:

After the MMTP packet is ULE-encapsulated and converted into a ULE packet, it must be further encapsulated, and through this, it is converted into a TS packet. As shown in Fig. 4, a TS packet generally includes a fixed length packet header of 4 bytes, a variable length packet header adaptation field, and a data segment not exceeding 184 bytes. For each ULE packet, the present invention divides it into a plurality of data segments not exceeding 184 bytes, and puts each data segment into a load of the TS packet. In particular, when the TS receiver of the transmission system is not intended to receive only the ULE data segment including the converted MMTP data, the present invention occupies 9 bytes of the variable length packet header adaptation field to insert the indication information. Thus, the TS receiver determines the currently received content as a ULE data segment, and describes the properties of the encapsulated content. When the corresponding adaptation field is activated, the size of the data segment of the ULE is reduced to 175 bytes. In the packet header of the converted TS packet, each field is set as follows:

Sync Byte: 8 bits, here set to 0x47;

Error code indication: 1 bit, if there is an uncorrectable bit error in the TS packet, set to “1”;

Unit start indication: 1 bit, set to “1” when the load data is the first data segment after dividing the ULE packet;

Priority: 1 bit, in packets with the same PID, set to “1” if the priority is higher;

PID: 13 bits, corresponding to packet_id in MMTP;

Scrambling Control: 2 bits, indicating the scrambling method of the load;

AF control: 2 bits, indicating whether a packet header adaptation field is included after the packet header (Adaption Field);

Consecutive counter: 4 bits, incremented for each packet with the same PID.

If necessary, in the packet header adaptation field (AdptationField), the fields to be specially set are as follows:

Adaptive field length: 1 byte, indicating the length of the extended field, calculated as 9 bytes, that is, set to “0x09”;

Discontinuity Status Indicator: 1 bit, indicating the discontinuous status of the current transmitted data packet;

Random Access Indicator: 1 bit, indicating whether the currently transmitted stream packet contains information to aid random access;

Basic Stream Priority Indicator: 1 bit, indicating the priority of the payload among the same packet;

PCR identifier: 1 bit, identifies whether the corresponding adaptation field contains a PCR field, set to “0”;

OPCR identifier: 1 bit, identifies whether the corresponding adaptation field contains the OPCR field, and is set to “0”;

Splicing Point Identifier: 1 bit, Identifies whether the corresponding adaptation field includes the splice_countdown field, set to “0”;

Private data transmission identifier: 1 bit, identifying whether the corresponding adaptation field contains a private data field, set to “1”;

Adaptive field extension identifier: 1 bit, identifies whether an extension field is included in the corresponding adaptation field, and is set to “0”;

In the private data field, the field length (transport_private_data_length) is calculated as “6”, that is, set to “0x06”, and the field byte (transport_private_data_byte) is set to “IS_ULE”, indicating that the data in the TS packet is a ULE data segment. After unpacking and splicing, it must be unpacked again with ULE packets, and MMTP is obtained and media work is performed by the MMT receiver.

Based on the above-described transmission protocol conversion method based on the broadcast system, the present invention further provides a transmission protocol conversion system based on the broadcast system, the system comprising:

an initial encapsulation module for encapsulating a media resource into a first protocol packet according to a first protocol;

a packet conversion module for converting a first protocol packet into a packet to obtain a TS packet for network transmission;

and a decapsulation module for mutually converting a received TS packet with a packet conversion module to obtain a first protocol packet.

In addition to implementing the system provided by the present invention and its various devices, modules and units in pure computer readable program code manner, the system and its various devices, modules provided by the present invention through logical programming of method steps , it is known to those skilled in the art that the same functionality can be fully implemented in the form of units such as logic gates, switches, dedicated integrated circuits, programmable controllers and embedded microcontrollers. Accordingly, the system provided by the present invention and its various devices, modules, and units can be regarded as one hardware member, and the devices, modules, and units for implementing various functions included therein are also structures within the hardware member. may be considered, and an apparatus, module, or unit for implementing various functions may be regarded as a structure in a hardware member as well as a software module of an implementation method.

Specific examples of the present invention have been described above. It should be understood that the present invention is not limited by the above specific embodiments, and those skilled in the art may make various changes or modifications within the scope of the claims, which do not affect the substantial content of the present invention. As long as there is no conflict, the embodiments of the present application and the features of the embodiments may be arbitrarily combined with each other.

Claims (22)

In the transmission protocol conversion method based on a broadcast system,
an initial encapsulation step of encapsulating the media resource into a first protocol packet according to the first protocol;
A packet conversion step of converting the first protocol packet into a packet to obtain a TS packet for network transmission; and
The first protocol is an MMT protocol, the first protocol packet is an MMT protocol packet,
The first protocol packet is through encapsulation in which the grammar format is a head field (HDR), the first protocol packet and a CRC segment, the head field (HDR) includes a length field, and the length field contains 16 bits. A transport protocol conversion method based on a broadcast system, characterized in that it occupies and is used to indicate the byte length of the first protocol packet. According to claim 1,
The packet conversion step includes:
a lightweight encapsulation step of lightweight encapsulating the first protocol packet to obtain a lightweight encapsulation packet;
TS encapsulation step of obtaining a TS packet by TS encapsulating the lightweight encapsulation packet. 3. The method of claim 2,
The packet structure of the lightweight encapsulation packet includes a head field (HDR), a first protocol data segment and a CRC segment,
the first protocol data segment is a lightweight encapsulation packet load, that is, a first protocol packet,
The CRC segment is a transmission protocol conversion method based on a broadcast system, characterized in that it is a cyclic redundancy check code. 4. The method of claim 3,
The head field is
A transport protocol conversion method based on a broadcast system, characterized in that it further comprises a type indicating the type of the first protocol packet. 4. The method of claim 3,
The CRC segment is a transport protocol conversion method based on a broadcast system, characterized in that 32 bits. 3. The method of claim 2,
The TS packet includes a packet header and a load segment,
The packet header is
sync bytes;
Error code indication: Set to “1” if there is an uncorrectable bit error in the TS packet;
Unit Start Indication: set to "1" if the load segment is the first data segment after splitting the lightweight encapsulation packet;
Priority: In packets with the same PID, set to “1” if the priority is higher;
PID: corresponding to the first protocol packet;
Scrambling control: indicates the scrambling method of the rod;
AF control: indicates whether a packet header adaptation field is included after the packet header;
A transmission protocol conversion method based on a broadcast system, comprising: a continuous counter: incremented according to a packet having the same PID. 7. The method of claim 6,
the synchronization byte is 8 bits,
The error code indication is 1 bit,
The unit start indication is 1 bit,
The priority is 1 bit,
The PID is 13 bits,
The scrambling control is 2 bits,
The AF control is 2 bits
The continuous counter is 4 bits; A transmission protocol conversion method based on a broadcast system, characterized in that. According to claim 1,
A transmission protocol conversion method based on a broadcast system, further comprising: a decapsulation step of obtaining a first protocol packet by performing packet conversion mutually with the packet conversion step on the received TS packet. In the transmission protocol conversion method based on a broadcast system,
a packet conversion step of performing reverse packet conversion on the received TS packet;
A decapsulation step of obtaining a first protocol by decapsulating the first protocol packet obtained through reverse packet conversion;
The first protocol packet is an MMT protocol packet, the first protocol is an MMT protocol,
The obtained first protocol packet is through reverse packet conversion whose grammar format is a head field (HDR), the first protocol packet and a CRC segment,
The head field (HDR) includes a length field, the length field occupies 16 bits and is used to indicate the byte length of the first protocol packet, transmission protocol conversion based on a broadcast system Way. 10. The method of claim 9,
The reverse packet conversion is
TS encapsulation and decapsulation step of decapsulating the received TS packet to obtain a lightweight encapsulation packet;
A transport protocol conversion method based on a broadcast system, comprising: a lightweight encapsulation and decapsulation step of decapsulating the received lightweight encapsulation packet to obtain a first protocol packet. In a transmission protocol conversion system based on a broadcast system,
an initial encapsulation module for encapsulating a media resource into a first protocol packet according to a first protocol;
A packet conversion module that converts the first protocol packet into a packet to obtain a TS packet for network transmission;
The first protocol is an MMT protocol, the first protocol packet is an MMT protocol packet,
The first protocol packet is through encapsulation in which the grammar format is a head field (HDR), the first protocol packet and a CRC segment, the head field (HDR) includes a length field, and the length field contains 16 bits. A transport protocol conversion system based on a broadcast system, characterized in that it occupies and is used to indicate the byte length of the first protocol packet. 12. The method of claim 11,
The packet conversion module,
a lightweight encapsulation module for lightweight encapsulating the first protocol packet to obtain a lightweight encapsulation packet;
and a TS encapsulation module for obtaining a TS packet by TS encapsulating the lightweight encapsulation packet. 13. The method of claim 12,
The packet structure of the lightweight encapsulation packet includes a head field (HDR), a first protocol data segment, and a CRC segment,
the first protocol data segment is a lightweight encapsulation packet load, that is, a first protocol packet,
The CRC segment is a transmission protocol conversion system based on a broadcast system, characterized in that it is a cyclic redundancy check code. 14. The method of claim 13,
The head field is
A transport protocol conversion system based on a broadcast system, characterized in that it further comprises a type indicating the type of the first protocol packet. 14. The method of claim 13,
The CRC segment is a transmission protocol conversion system based on a broadcast system, characterized in that 32 bits. 13. The method of claim 12,
The TS packet includes a packet header and a load segment,
The packet header is
sync bytes;
Error code indication: Set to “1” if there is an uncorrectable bit error in the TS packet;
Unit Start Indication: Set to “1” if the load segment is the first data segment after splitting the lightweight encapsulation packet;
Priority: In packets with the same PID, set to “1” if the priority is higher;
PID: corresponding to the first protocol packet;
Scrambling control: indicates the scrambling method of the rod;
AF control: indicates whether a packet header adaptation field is included after the packet header;
A transmission protocol conversion system based on a broadcast system, comprising: a continuous counter: incremented according to packets having the same PID. 17. The method of claim 16,
the synchronization byte is 8 bits,
The error code indication is 1 bit,
The unit start indication is 1 bit,
The priority is 1 bit,
The PID is 13 bits,
The scrambling control is 2 bits,
The AF control is 2 bits,
The transmission protocol conversion system based on the broadcast system, characterized in that the continuous counter is 4 bits. 12. The method of claim 11,
Transmission protocol conversion system based on a broadcast system, characterized in that it further comprises a decapsulation module for mutually converting the received TS packet with the packet conversion module to obtain a first protocol packet. In a transmission protocol conversion system based on a broadcast system,
a packet conversion module that performs reverse packet conversion on the received TS packet;
and a decapsulation module for decapsulating the first protocol packet obtained through reverse packet conversion to obtain a first protocol;
The first protocol packet is an MMT protocol packet, the first protocol is an MMT protocol,
The obtained first protocol packet is through reverse packet conversion whose grammar format is a head field (HDR), the first protocol packet and a CRC segment,
The head field (HDR) includes a length field, the length field occupies 16 bits and is used to indicate the byte length of the first protocol packet, transmission protocol conversion based on a broadcast system system. 20. The method of claim 19,
The reverse packet conversion is
a TS encapsulation and decapsulation module for decapsulating the received TS packet to obtain a lightweight encapsulation packet;
A transport protocol conversion system based on a broadcast system, comprising: a lightweight encapsulation and decapsulation module for decapsulating the received lightweight encapsulation packet to obtain a first protocol packet. delete delete

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