CN1972453A - A data flow packaging method of mobile multimedia broadcasting system - Google Patents

Abstract

The present invention relates to a data stream encapsulation method for a mobile multimedia broadcasting system, characterized in that the multimedia data stream is encapsulated in a data frame structure, and the data frame includes a frame header and one or more of a video segment, an audio segment, and a data segment The payload of this composition; The frame header includes a video segment indication, an audio segment indication and a data segment indication, the video segment indication represents whether the video segment exists in the data frame, and the audio segment indication represents the audio segment in the data frame Whether the data segment exists in the frame, the data segment indicates whether the representative data segment exists in the data frame. Effectively transmit multimedia data streams in a channel by encapsulating segments, and at the same time use component labels to transmit only necessary components and correspondingly call necessary component playback programs on mobile terminals, improve transmission efficiency, save mobile terminal power, and better meet mobile multimedia services need.

Description

A data stream encapsulation method for mobile multimedia broadcasting system

technical field

The invention relates to multimedia broadcasting technology, in particular to a data encapsulation method of a mobile multimedia broadcasting system.

Background technique

Mobile multimedia broadcasting is a multimedia playback technology that has emerged in recent years. With a handheld terminal, you can watch TV while moving at high speed. The terminal receives the program list through the wireless protocol, and can select the channel it has the right to watch, so that it can receive the multimedia data of the selected channel, and realize watching TV on the mobile terminal.

The mobile multimedia broadcasting system is divided into different channels. The media data stream transmitted by each channel can include video segments, audio segments, and data segments according to the characteristics of the media data. It needs to be adapted and transmitted on the channels of the mobile multimedia broadcasting system through multiplexing technology. , the mobile multimedia broadcast receiving terminal can receive corresponding video segments, audio segments, and data segments, and play them on the terminal.

There are two existing encapsulation methods for media data streams:

First, transport stream TS mode. The TS protocol is one of the MPEG standards of the Moving Picture Experts Group. It transmits video, audio, and data in a fixed-length 188-byte packet. By sending a clock correction packet, Functions such as clock synchronization have been realized.

Second, the Real-time Transport Protocol (RTP) method is a method of transmitting media data streams on an IP network. The size of the packet is not fixed. The time stamp of each packet header is used to ensure the synchronization of the playback time, and the sequence number is used to ensure the playback order of the packets.

The existing methods have their own advantages and disadvantages. The RTP method can only be used on the IP network, and the TS method uses a fixed length, resulting in relatively low transmission efficiency, often lower than 90%.

On the other hand, the wireless bandwidth that the service network can provide to each mobile terminal is very limited, and sufficient transmission rate is required to meet the clear display of the terminal, but the low transmission efficiency will inevitably lead to a decrease in the actual transmission rate, which may not reach the mobile terminal. Business requirements for multimedia broadcasting.

Contents of the invention

The technical problem to be solved in the present invention is to provide a data frame encapsulating the data flow of the mobile multimedia broadcasting system to meet the requirements of the mobile multimedia broadcasting.

A data stream encapsulation method for a mobile multimedia broadcasting system, characterized in that the multimedia data stream is encapsulated using a data frame structure, and the data frame includes a frame header and one or more of a video segment, an audio segment, and a data segment Payload: The frame header includes a video segment indication, an audio segment indication and a data segment indication, the video segment indication represents whether the video segment exists in the data frame, and the audio segment indication represents whether the audio segment exists in the data frame exists, the data segment indicates whether the representative data segment exists in the data frame.

According to the method of the present invention, the frame header further includes segment parameters, which are in one-to-one correspondence with the video segment, audio segment and data segment.

According to the method of the present invention, the segment parameters corresponding to the video segment include the length of the video segment, the encoding type and rate of the video segment.

According to the method of the present invention, the segment parameters corresponding to the audio segment include the length of the audio segment, the encoding type and rate of the audio segment.

According to the method of the present invention, the segment parameter corresponding to the data segment includes the length of the data segment.

According to the method of the present invention, the frame header also includes a frame header length.

According to the method of the present invention, the mobile multimedia broadcasting system assembles one or more of the video segment, audio segment and data segment that need to be transmitted within a period of time according to the structure of the data frame and transmits it on the channel;

According to the method of the present invention, the mobile multimedia terminal receives and disassembles the variable-length data frame according to the segment instruction, takes out the video segments, audio segments or data segments one by one, and then processes them.

According to the method of the present invention, the thing to be transmitted may be one or more of video segment, audio segment and data segment.

The present invention effectively transmits in a channel by encapsulating the segments of the multimedia data stream, each segment needs to transmit segment parameters in the frame header, and the segment parameters are used to provide the mobile terminal to play segments, in order to avoid redundant segments and segment parameters The transmission of the multimedia broadcasting system saves channel resources, and there is a segment indication in the frame header to indicate the segment in the media data stream. Clearly indicate the segment composition of the media data stream through segment indication, only transmit necessary segments and segment parameters, avoid transmitting unnecessary segments and segment parameters, and improve the transmission efficiency of multimedia broadcasting systems, for example, only audio segments are transmitted in audio broadcasting channels and audio segment parameters, there are only audio segment parameters in the frame header, there are no video data segment parameters and data segment parameters, which reduces the overhead of encapsulation, improves the efficiency of encapsulation, and supports efficient transmission of mobile multimedia broadcasting systems; at the same time, the segment indication can also guide The multimedia broadcast receiving terminal playback program only uses the playback program of the channel media data stream segment in the terminal, and does not need to use the playback program of all segments, so that the terminal is more power-saving and the battery life of the mobile terminal is extended.

Description of drawings

The present invention will be further described in detail below in conjunction with the accompanying drawings and specific embodiments.

FIG. 1 is a schematic diagram of a frame structure adopted in the present invention.

FIG. 2 is a schematic diagram of a frame header structure in the frame structure shown in FIG. 1 .

FIG. 3 is a schematic diagram of the internal logical relationship between the video segment and the corresponding part of the frame header in the frame structure shown in FIG. 1 .

FIG. 4 is a schematic diagram of the internal logical relationship between the audio segment and the corresponding part of the frame header in the frame structure shown in FIG. 1 .

FIG. 5 is a schematic diagram of the internal logical relationship between the data segment and the corresponding part of the frame header in the frame structure shown in FIG. 1 .

Detailed ways

The key of the present invention is segment indication, segment parameters and segments are combined into a complete encapsulation frame, segment indication and segment parameters are placed in the frame header, and segment is used as the payload of the frame. A segment indication is used to indicate whether the frame contains corresponding segment parameters and segments.

The present invention encapsulates one or more segments of the multimedia data stream together to realize high efficiency of data transmission, including the following aspects:

(1) The multimedia broadcasting system has multiple channels, and each channel transmits the media data stream of the channel.

(2) The media data stream can include video segments, audio segments, and data segments, and the media data stream can be composed of one or more of these segments. For example, the media data stream can only include video segments and audio segments without data segments; or media A data stream can have only audio and data segments.

(3) The media data stream uses a flexible encapsulation format, which is composed of frame header, video segment, audio segment, data segment, etc.

(4) The frame header is a parameter describing the media data stream, including the length information of the frame header, segment indication information of the media data stream, segment parameters, and the like.

(5) The segment indication of the media data stream includes a video segment indication, an audio segment indication and a data segment indication. The video segment indication is used to indicate whether a video segment is included in the media data stream; the audio segment indication is used to indicate whether an audio segment is included in the media data stream; the data segment indication is used to indicate whether a data segment is included in the media data stream;

(6) The segment parameters in the frame header are determined according to the segment indication. If the video segment indication indicates that the media data stream of this channel contains a video segment, the frame header contains the parameters of the video segment, such as the length of the video segment and the encoding type of the video segment and rate parameters; if the audio segment indication indicates that the media data stream contains the audio segment, the frame header contains the parameters of the audio segment, such as the length of the audio segment, the encoding type and rate of the audio segment; if the data segment indication indicates the media data If the stream contains data segments, the frame header contains parameters of the data segment, such as the length of the data segment;

The present invention is to the encapsulation method of video data segment, audio data segment, data segment in multimedia broadcasting media flow, specifically as shown in Figure 1, mobile multimedia broadcasting has a plurality of channels 3, and each channel 3 transmits the media data flow of different programs, The encapsulated media stream is composed of frame header 10, video segment 21, audio segment 22, and data segment 23. Each segment needs to transmit segment parameters in the frame header, and the segment parameters are used when providing the playback segments of the mobile terminal. In order to reduce redundant The transmission of the segment and segment parameters saves the channel resources of the multimedia broadcasting system, and there is a segment indication in the frame header to indicate the segment in the media data stream.

As shown in FIG. 2 , the media data stream is composed of a frame header 10 and a payload 20 , wherein the frame header 10 is mainly some control information and must be provided. The specific contents are:

(1) Frame header length information 101: indicates the length of the frame header.

(2) Video segment indication 102 .

(3) Audio segment indication 103 .

(4) Data segment indication 104 .

(5) Segment parameters 105, which may include video segment parameters 1051, including: video segment length, video coding algorithm type, video coding bit rate, video frame rate, video horizontal resolution, video vertical resolution, etc.

(6) Segment parameters 105, which may include audio segment parameters 1052, including: audio data segment length, encoding algorithm type, encoding bit rate, sampling rate, etc.

(7) Segment parameter 105, which may include data segment parameter 1053, including: the length of the data segment, etc.

(8) Other information.

(9) Frame header check code 106.

The payload 20 includes a video data segment 21 , an audio data segment 22 and a data segment 23 .

As shown in FIG. 3 , the video segment indication 102 is used to indicate that the media data stream contains the video segment 21 and at the same time indicates that the frame header contains the parameter 1051 of the video data segment.

As shown in FIG. 4 , the audio segment indicator 103 is used to indicate that the media data stream contains the audio segment 22 and at the same time indicates that the frame header contains the parameter 1052 of the audio data segment.

As shown in FIG. 5 , the data segment indication 104 is used to indicate that the media data stream contains the data segment 23 and at the same time indicates that the frame header contains the parameter 1053 of the data segment.

Claims (9)

1. A data stream encapsulation method for a mobile multimedia broadcasting system, characterized in that, a data frame structure is used to encapsulate the multimedia data stream, and the data frame includes one or more of a frame header and a video segment, an audio segment, and a data segment , the frame header includes a video segment indication, an audio segment indication and a data segment indication, the video segment indication indicates whether the video segment exists in the data frame, and the audio segment indication indicates whether the audio segment exists in the data frame, The data segment indicates whether the representative data segment exists in the data frame. 2. The data stream encapsulation method of the mobile multimedia broadcasting system according to claim 1, wherein the frame header further includes segment parameters corresponding to the video segment, audio segment and data segment one by one. 3. The data stream encapsulation method of the mobile multimedia broadcasting system according to claim 2, wherein the segment parameters corresponding to the video segment include the length of the video segment, the encoding type and rate of the video segment. 4. The data stream encapsulation method of the mobile multimedia broadcasting system according to claim 2, wherein the segment parameters corresponding to the audio segment include the length of the audio segment, the encoding type and rate of the audio segment. 5. The data stream encapsulation method of the mobile multimedia broadcasting system according to claim 2, wherein the segment parameter corresponding to the data segment includes the length of the data segment. 6. The data stream encapsulation method of the mobile multimedia broadcasting system according to claim 1, wherein the frame header further includes a frame header length. 7. The data stream encapsulation method of the mobile multimedia broadcasting system according to claim 1, wherein the mobile multimedia broadcasting system divides one or more of the video segments, audio segments and data segments that need to be transmitted within a certain period of time into The structure of the data frame is assembled and transmitted on the channel. 8. The data stream encapsulation method of the mobile multimedia broadcasting system according to claim 1, wherein the mobile multimedia terminal receives and disassembles the variable-length data frame according to the segment instruction, takes out the video segments one by one, audio segments or data segments, and then process them. 9. The data stream encapsulation method of the mobile multimedia broadcasting system according to claim 7, characterized in that, the one or more of the video segment, the audio segment and the data segment can be said to be transmitted.