WO2007051343A1

WO2007051343A1 - A bandwidth adaptive stream medium transmission system of a stream medium serving system and a method thereof

Info

Publication number: WO2007051343A1
Application number: PCT/CN2005/001795
Authority: WO
Inventors: Zunyou Ke; Liang Guo; Jie Hu; Ji Lv; Tao Yu; Jiming Zhang
Original assignee: Zte Corporation
Priority date: 2005-10-31
Filing date: 2005-10-31
Publication date: 2007-05-10
Also published as: CN101352009A; CN101352009B

Abstract

A bandwidth adaptive stream medium transmission system of a stream medium serving system and a method thereof are provided, the system includes a client and a stream medium server, the method comprises the steps: the stream medium server transmits a bandwidth detecting message packet to the client; the client transmits a bandwidth detecting feedback message packet to the stream medium server; the stream medium server calculates the average packet-lost rate based on the bandwidth detecting feedback message packets of the client during a period of time; the stream medium server performs logical control and judges whether to decode and encode again according to the average packet-lost rate; the stream medium server performs decoding and encoding according to the average packet-lost rate; the stream medium server transmits the re-encoded stream medium packets. The system and method of present invention improve the QoS of the stream medium, decrease the system development difficulty and increase the system reliability.

Description

Bandwidth adaptive streaming media transmission system and method for streaming media service system

The present invention relates to the field of network communication technologies, and relates to a method and a method for processing streaming media data adapted to adapt to bandwidth changes on a network, and in particular, to a bandwidth adaptive streaming media transmission system and method for a streaming media service system. Background technique

With the rapid development of communication networks, the streaming media service based on the Internet Protocol (IP) network has gradually become a business form that people enjoy in daily work and life, and the stability of media stream transmission on the network is guaranteed. It is also growing stronger. It is well known that an IP network is an open network, and it is not guaranteed that the bandwidth of the IP network for data communication is stable. Moreover, when using a mobile terminal to access streaming media, the bandwidth of the wireless side is also good or bad. In order to meet the communication needs of adapting to bandwidth changes, experts have also proposed some methods.

At present, the main way to implement bandwidth adaptive streaming media transmission is to provide several different bit rate encoded streaming media data for each media file in advance, and use a bit rate high or according to the detected bandwidth. Low streaming media data.

Since the existing method must prepare much more streaming media data than the original data, the storage overhead of the streaming media service system is increased. In addition, during the use, when the bandwidth changes, switching to another media stream and relocating This way to the current picture inevitably brings a large pause to the recipient. The multiple streaming media data of the same content also increases the complexity of the system. It is not conducive to reducing the cost of the system, the difficulty of development and the reliability of the system, and is not conducive to the flexibility of system processing.

Patent Document existing comprising: Chinese Patent Application No. 02159354 of application "Method for adaptively adjusting the video quality of the network," and U.S. Patent Application Publication No. 20050108414 specifically Wo of ^{1 J "System and method for transmitting} data in computer systems using Virtual streaming" (system and method of using virtual streams to transfer data in a computer system).

The Chinese patent application with the application number 02159354 has the following shortcomings: 1. The patent does not provide a solution for streaming media services. This solution is the core technology of bandwidth adaptive streaming media transmission. 2. The method adopted by the system is not the target system. The specification system uses custom processing and interface modules. This patent only proposes a method to solve bandwidth measurement using a separate module outside the specification system, so it is difficult to integrate into the existing streaming media service specification system. In addition, because additional processing modules and interfaces that must be added will inevitably increase the complexity of the system, the development of the system is more difficult and the reliability of the system is reduced.

U.S. Patent Application Publication No. 20050108414 has the following disadvantages: This patent proposes a system and method for variable virtual flow to accommodate bandwidth changes for data transmission. The method divides the data to be transmitted into a plurality of small parts, transmits them through multiple channels allowed in the bandwidth, and then combines them at the destination end. The method is based on simple segmentation of data, rather than on the basis of data coding analysis, and does not provide a solution for logical segmentation of coded data. In addition, the multi-channel adaptation of the bandwidth increases the complexity of the system, increases the difficulty of system development and reduces the reliability of the system. Summary of the invention In view of the above, an object of the present invention is to provide a bandwidth adaptive streaming media transmission system and method for a streaming media service system to improve streaming media service quality.

To achieve the above objective, a bandwidth adaptive streaming media transmission system of a streaming media service system of the present invention includes:

The client, which is responsible for providing an IP-based communication mechanism, provides a transmission channel for streaming data transmission and bandwidth detection message transmission, such as Real Time Transport Protocol (RTP) and Real Time Transport Control Protocol (Realtime Transport). Control Protocol) (hereinafter referred to as RTCP); it is responsible for receiving the bandwidth detection message packet, transmitting the bandwidth detection feedback message packet, and receiving the streaming media data packet, and decoding and processing the streaming media data packet to play the audio and video;

The streaming media server is responsible for providing an IP-based communication mechanism, providing a transmission channel for streaming data transmission and bandwidth detection message transmission, such as RTP, RTCP, etc.; it is responsible for packaging and transmitting the bandwidth detection message. The message packet, receiving the bandwidth detection feedback message packet, calculating an average packet loss rate within a preset time (for example, 10 seconds), and performing logical control and secondary decoding coding; wherein the architecture of the streaming media server side includes: Stream and media data streams. The control flow includes: a bandwidth detection message sending module, a bandwidth detection feedback message receiving module, a bandwidth detection feedback message parsing module, and a bandwidth adaptation logic control module; the media data stream includes: a media data receiving module, and a media data. Decoding module, media data encoding module and media data streaming and sending module.

The bandwidth detection message sending module is configured to send the bandwidth detection message packet to the client, and the bandwidth detection feedback message receiving module is configured to receive the bandwidth detection feedback message packet returned by the client, and the bandwidth detection feedback message is parsed. The module is responsible for parsing the above bandwidth detection Detecting a feedback message packet, and taking out field information related to bandwidth detection, such as a packet loss rate; the bandwidth adaptation logic control module is configured to calculate an average packet loss rate within a predetermined time period, and determine according to the average packet loss rate. Whether it is necessary to perform secondary decoding and encoding; the media data receiving module is responsible for reading the streaming media data packet; the media data decoding module is responsible for decoding the streaming media data packet to be sent by the streaming media server end, because the media encoding format is numerous, The media data decoding module may be composed of a plurality of different media data decoding modules; the media data encoding module is configured to recalculate the encoded code rate according to the average packet loss rate, and re-encode the streaming media data packet according to the code rate. The media data encoding module may be composed of a plurality of different media data encoding modules; the media data streaming and sending module is responsible for streaming and transmitting the streaming media data packet to the client.

In addition, since the foregoing media server needs the client to continuously report the network status, the bandwidth detection message packet and the bandwidth detection feedback message packet are non-one-to-one correspondence mechanisms, that is, one bandwidth detection message may return multiple pieces. Bandwidth detection feedback message.

To achieve the above objective, a bandwidth adaptive streaming media transmission method of a streaming media service system of the present invention includes the following steps:

Step 1: The streaming media server sends a bandwidth detection message packet to the client.

Step 2: The streaming media server receives the bandwidth detection feedback packet returned by the client.

Step 3: The streaming media server parses the bandwidth detection feedback message packet, and calculates an average packet loss rate within a preset time period;

Step 4: The streaming media server determines whether secondary decoding coding is required. If the average packet loss rate is below a preset ratio (the ratio can be configured, for example, 20%), then No need to perform secondary decoding and encoding, perform step 7, otherwise perform step 5;

Step 5: If the average packet loss rate is greater than the preset ratio, the streaming media server decodes the sent streaming media packet;

Step 6: The streaming media server reduces the encoded code rate according to the average packet loss rate and percentages, and re-encodes the decoded streaming media data packet according to the code rate. Step 7: The foregoing streaming media server sends Streaming data packets.

The above preset time can be configured, and in order to reduce the network load, the time should not be set too small.

The method of lowering the coded rate by percentage in the above step 6 is: code rate = starting code rate X (1 - average packet loss rate).

Compared with the prior art, the present invention introduces a secondary decoding and coding mechanism based on bandwidth detection, so that when the communication line is in a bad condition, the code rate of the transmitted streaming media data packet can be dynamically adjusted in time to enable it to Adapt to network bandwidth; when the communication line is in good condition, the streaming code packet is always sent using the default bit rate. In this way, regardless of the status of the communication network, the smooth playback of streaming media packets is not affected. At the same time, since the encoding and decoding module can be provided through the streaming server server plug-in component, or the interface is provided by a third party, the system development difficulty is reduced and the system is improved. Reliability.

The above and other objects, features, and advantages of the present invention will become more apparent and understood by the appended claims appended claims Attachment 3⁄4昍

1 is a schematic structural diagram of a streaming media server end according to the present invention; Figure 2 is a flow chart of the method of the present invention;

Figure 3 is a timing diagram of the method of the present invention. detailed description

The specific implementation of the technical solution of the present invention will be further described in detail below with reference to the accompanying drawings, which are not intended to limit the invention. As shown in FIG. 1, the architecture of the streaming media server of the present invention includes a control flow and a media data stream, which are respectively indicated by thin lines and black thick lines in the figure:

1) The control flow consists of the following parts:

The bandwidth detection message sending module 201, in the process of streaming media playback, initiates a bandwidth detection process, and sends a bandwidth detection message packet to the client;

The bandwidth detection feedback message receiving module 101 is configured to receive the bandwidth detection feedback message packet returned by the client, and the bandwidth detection feedback message packet and the bandwidth detection message are required because the streaming media server end needs the client to continuously report the network status. The packet is a non-one-to-one correspondence mechanism, that is, one bandwidth detection message may return multiple bandwidth detection feedback messages;

The bandwidth detection feedback message parsing module 102 is configured to parse the bandwidth detection feedback message packet, and take out field information such as a packet loss rate related to bandwidth detection;

The bandwidth adaptation logic control module 103 is configured to calculate an average packet loss rate within a predetermined time period, and determine, according to the average packet loss rate, whether secondary decoding coding is required;

2) The media data stream consists of the following components:

a media data receiving module 304, which is responsible for reading a streaming media data packet;

The media data decoding module 303 is responsible for the stream to be sent by the streaming media server end. The media data packet is decoded. Due to the large number of media encoding formats, the media data decoding module may be composed of a plurality of different media data decoding modules;

The media data encoding module 302 is configured to recalculate the encoded code rate according to the average packet loss rate, and re-encode the streaming media data packet according to the code rate. Because the media encoding format is numerous, the media data encoding module may be multi-coded. The media data streaming and sending module 301, the streaming media data packet is streamed and sent to the client.

As shown in FIG. 2, the method of the present invention includes the following steps:

Step 3: The streaming media server parses the bandwidth detection feedback message packet, and calculates an average packet loss rate within a preset time (for example, 10 seconds);

Step 4: The streaming media server determines whether secondary decoding is required. If the average packet loss rate is lower than a preset ratio (for example, 20%), the secondary decoding encoding is not required, and step 7 is performed. Otherwise, Perform step 5;

Step 5: If the average packet loss rate is greater than the foregoing preset ratio, the streaming media server decodes the sent streaming media packet.

Step 6: The streaming media server reduces the encoded code rate according to the average packet loss rate and percentages, and re-encodes the decoded streaming media data packet according to the code rate; wherein the foregoing code rate is reduced by percentage The method is: code rate = starting code rate X (1 - average packet loss rate), for example, starting code rate is 100 kbps, average packet loss rate is 40%, then re-encoding The code rate is 100X (1 -40%) = 60kbps;

Step 7: The streaming media server sends the streaming media packet.

As shown in FIG. 3, the timing of the method of the present invention is as follows:

Step A. The streaming media server sends a bandwidth detection message packet to the client.

Step B. The client sends a bandwidth detection feedback message packet to the streaming media server, and the feedback message may be multiple;

Step C. The streaming media server detects the feedback packet according to the bandwidth of the client in a period of time, and calculates an average packet loss rate.

Step D. The streaming media server performs logical control according to the average packet loss rate to determine whether secondary decoding and encoding are required.

Step E: The streaming media server performs decoding, and re-encodes according to the average packet loss rate. Step F. The streaming media server sends the re-encoded streaming media data packet.

The above is a detailed description of the working principle of the present invention, but this is only a visual example for the purpose of understanding and should not be construed as limiting the scope of the invention. Also, various possible equivalents and substitutions may be made in accordance with the description of the technical solutions of the present invention and the preferred embodiments thereof, and all such changes or substitutions are intended to fall within the scope of the appended claims.

Claims

Rights request

A bandwidth adaptive streaming media transmission system for a streaming media service system, comprising:

The client is responsible for providing an internet protocol-based communication mechanism, and is responsible for receiving a bandwidth detection message packet, transmitting a bandwidth detection feedback message packet, and receiving the streaming media data packet, and decoding the streaming media data packet;

The streaming media server is responsible for providing an internet protocol-based communication mechanism, and is configured to package the bandwidth detection message and send the bandwidth detection message packet, receive the bandwidth detection feedback message packet, and calculate an average lost time in a preset time. The packet rate and the logic control and the secondary decoding coding; wherein the architecture of the streaming media server includes: a control flow and a media data flow, wherein the control flow includes: a bandwidth detection message sending module, a bandwidth detection feedback message receiving module The bandwidth detection feedback message parsing module and the bandwidth adaptation logic control module; the media data stream includes: a media data receiving module, a media data decoding module, a media data encoding module, and a media data streaming and sending module.

2. The system of claim 1 wherein

The bandwidth detecting message sending module is configured to send the bandwidth detecting message packet to the client.

The bandwidth detection feedback message receiving module is configured to receive the bandwidth detection feedback message packet returned by the client;

The bandwidth detection feedback message parsing module is configured to parse the bandwidth detection feedback message packet, and take out field information related to bandwidth detection; The bandwidth adaptation logic control module is configured to calculate an average packet loss rate within a preset time period, and determine, according to the average packet loss rate, whether secondary decoding coding is required;

The media data receiving module is configured to read the streaming media data packet;

The media data decoding module is configured to decode the streaming media data packet to be sent by the streaming media server end;

The media data encoding module is configured to recalculate the encoded code rate according to the average packet loss rate, and re-encode the streaming media data packet according to the code rate;

The media data streaming and sending module is configured to stream the streaming media packet and send the packet to the client.

3. The system according to claim 2, wherein the bandwidth detection message packet and the bandwidth detection feedback message packet are non-one-to-one correspondence mechanisms.

A bandwidth adaptive streaming media transmission method for a streaming media service system, comprising the steps of:

Step 4: The streaming media server determines whether secondary decoding is required. If the average packet loss rate is lower than a preset ratio, the secondary decoding and encoding are not required, and step 7 is performed; otherwise, step 5 is performed;

Step 5: If the average packet loss rate is greater than the preset ratio, the streaming medium The server side decodes the sent streaming media packet;