WO2017080450A1

WO2017080450A1 - Multi-media data download method, client, server, system and storage medium

Info

Publication number: WO2017080450A1
Application number: PCT/CN2016/105164
Authority: WO
Inventors: 陈光亮; 周美艳; 韦月飞
Original assignee: 中兴通讯股份有限公司
Priority date: 2015-11-10
Filing date: 2016-11-09
Publication date: 2017-05-18
Also published as: CN106686036A

Abstract

A multi-media data download method, a client, a server, a multi-media data download system and a computer storage medium. The multi-media data download method comprises the following steps: when detecting a change in a network bandwidth, a client determines a first code rate corresponding to the changed network bandwidth, and determines sub-segment data of a segment file of multi-media data being downloaded at present; the client monitors a boundary identifier of the determined sub-segment data; the client downloads next sub-segment data of the segment file corresponding to the first code rate from a server when the downloaded data arrives at the boundary identifier.

Description

Multimedia data downloading method, client, server, system and storage medium

Technical field

The present invention relates to the field of multimedia technologies, and in particular, to a multimedia data downloading method, a client, a server, a system, and a computer storage medium.

Background technique

With the development of communication technology, the application of multimedia technology is becoming wider and wider. In the process of downloading and playing multimedia data, if the network bandwidth changes, the download terminal must wait for the download of the currently downloaded segment file to complete, and then download the next segment file with the appropriate code rate according to the network bandwidth. The traditional download method often causes the rate switching to lag behind the change of the client network bandwidth, and the real-time performance of the rate switching is poor, which leads to a decrease in user experience.

Therefore, in the existing multimedia data downloading process, how to improve the efficiency of the code rate switching when the network bandwidth changes, the problem in this aspect needs to be solved by the inventor.

The above content is only used to assist in understanding the technical solutions of the present invention, and does not constitute an admission that the above is prior art.

Summary of the invention

The embodiments of the present invention are directed to a multimedia data downloading method, a client, a server, a system, and a computer storage medium, which solve the problem of how to improve the rate switching efficiency when the network bandwidth changes in the existing multimedia data downloading process.

In order to achieve the above object, the technical solution of the present invention is achieved as follows:

An embodiment of the present invention provides a multimedia data downloading method, where the multimedia data downloading method includes the following steps:

When the client detects a change in the network bandwidth, the client determines the changed network bandwidth. a first code rate and determining sub-segment data of the segment file of the multimedia data currently being downloaded;

The client monitors the boundary identifier of the determined sub-segment data;

When the downloaded data reaches the boundary identifier, the client downloads the next sub-segment data of the corresponding segment file at the first code rate from the server.

In the above solution, when the downloaded data reaches the boundary identifier, the client downloads the next sub-segment data of the corresponding segment file in the first code rate from the server, including:

When the downloaded data reaches the boundary identifier, the client calculates a location of the next sub-segment data of the corresponding segment file in the first code rate;

The client generates the first request according to the calculated location information;

The client sends the first request to the server, and receives the next sub-segment data of the corresponding segment file under the first code rate returned by the server.

In the above solution, the client determines the first code rate corresponding to the changed network bandwidth when detecting the change of the network bandwidth, and determines the sub-segment data of the segment file of the multimedia data currently being downloaded. ,Also includes:

Sending, by the client, a second request to the server, to download an index file of the multimedia data from the server;

The client receives an index file returned by the server;

The client sequentially sends a request to the server according to the index file, and receives each segment file under the second code rate returned by the server.

In the above solution, after the step of downloading, by the client, the next sub-segment data of the corresponding segment file in the first code rate, the method includes:

When the client downloads the next sub-segment data corresponding to the segment file at the first code rate, the client plays the downloaded sub-segment data according to the first code rate.

In the above solution, the client sends a second request to the server to receive the service. Before the step of downloading the index file of the multimedia data, the method further includes:

The server generates an index file and a plurality of segment files according to the multimedia data;

The server adds corresponding decoding information at a starting position of each segment file;

Determining, by the server, the sub-segment data that can be code rate switched in the corresponding segment file according to each of the decoding information;

The server adds the location information of each sub-segment data to the index file, so that the client performs rate switching between the sub-segment data according to the network bandwidth when the client downloads the multimedia data.

An embodiment of the present invention further provides a client, where the client includes:

a determining module, configured to determine a first code rate corresponding to the changed network bandwidth when detecting a change in network bandwidth, and determine sub-segment data of the segment file of the multimedia data currently being downloaded;

a monitoring module configured to monitor a boundary identifier of the determined sub-segment data;

And a downloading module, configured to download the next sub-segment data of the corresponding segment file in the first code rate from the server when the downloaded data reaches the boundary identifier.

In the above solution, the downloading module includes a calculating unit, a generating unit, and a receiving unit;

a calculating unit, configured to calculate, when the downloaded data reaches the boundary identifier, a location of a next sub-segment data of the corresponding segment file in the first code rate;

a generating unit, configured to generate the first request according to the calculated location information;

The receiving unit is configured to send the first request to the server, and receive the next sub-segment data of the corresponding segment file in the first code rate returned by the server.

In the above solution, the downloading module is further configured to send a second request to the server to download an index file of the multimedia data from the server;

The downloading module is further configured to receive an index file returned by the server;

The downloading module is further configured to sequentially send a request to the service according to the index file And receiving each segment file at the second code rate returned by the server.

In the above solution, the client further includes a play module;

The playing module is configured to play the downloaded sub-segment data according to the first code rate when the downloading of the next sub-segment data of the corresponding segment file is completed at the first code rate.

In addition, in order to achieve the above object, an embodiment of the present invention further provides a server, where the server includes:

Generating a module, configured to generate an index file and a plurality of segment files according to the multimedia data;

Adding a module, configured to add corresponding decoding information at a starting position of each segment file;

The identifier module is configured to identify, according to each of the decoding information, sub-segment data that can be code rate switched in the corresponding segment file;

The adding module is further configured to add location information of each sub-segment data to the index file, so that when the client downloads the multimedia data, the rate switching is performed between the sub-segment data according to the network bandwidth.

In addition, in order to achieve the above object, an embodiment of the present invention further provides a multimedia data downloading system, where the multimedia data downloading system includes a client as described above and a server as described above.

In addition, in order to achieve the above object, an embodiment of the present invention provides a computer storage medium, where the computer storage medium stores a computer program, and the computer program is used to execute the multimedia data downloading method described above.

The multimedia data downloading method, the client, the server, the system, and the computer storage medium provided by the embodiments of the present invention monitor the network bandwidth when downloading the multimedia data, and wait for the currently downloaded multimedia data when detecting the change of the network bandwidth. After the sub-segment data download of the segment file is completed, the cell rate can be switched to another code rate, and the next sub-segment data of the corresponding segment file under another code rate is downloaded. You can quickly switch between code rates without waiting for the entire downloaded segment file to be downloaded. At the same time, the corresponding code rate is determined according to the changed network bandwidth, and the multimedia file is downloaded according to the fast switching rate of the network bandwidth, thereby improving the code rate switching efficiency.

DRAWINGS

1 is a schematic flow chart of a first embodiment of a method for downloading multimedia data according to the present invention;

2 is a schematic flowchart of a second embodiment of a method for downloading multimedia data according to the present invention;

3 is a schematic flowchart diagram of a third embodiment of a method for downloading multimedia data according to the present invention;

4 is a schematic flowchart diagram of a fourth embodiment of a method for downloading multimedia data according to the present invention;

FIG. 5 is a schematic diagram of functional modules of a first embodiment of a client according to the present invention; FIG.

6 is a schematic diagram of functional modules of a second embodiment of a client according to the present invention;

7 is a schematic diagram of functional modules of a preferred embodiment of a server of the present invention;

FIG. 8 is a schematic diagram of functional modules of a preferred embodiment of a multimedia data download system of the present invention.

detailed description

The technical solutions in the embodiments of the present invention will be clearly and completely described in the following with reference to the accompanying drawings. It is understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

The main solution of the embodiment of the present invention is: when detecting that the network bandwidth changes, the client determines the first code rate corresponding to the changed network bandwidth, and determines the sub-segment of the segment file of the multimedia data currently being downloaded. Data; the client monitors the determined boundary identifier of the sub-segment data; and when the downloaded data reaches the boundary identifier, the client downloads the next segment of the corresponding segment file at the first code rate from the server. Sub-segment data.

In the existing multimedia data downloading process, how to improve the efficiency of rate switching when the network bandwidth changes.

Based on the above problems, the present invention provides a multimedia data downloading method.

Referring to FIG. 1, FIG. 1 is a schematic flowchart diagram of a first embodiment of a method for downloading multimedia data according to the present invention.

In this embodiment, the multimedia data downloading method includes:

Step S10: When detecting that the network bandwidth changes, the client determines a first code rate corresponding to the changed network bandwidth, and determines sub-segment data of the segment file of the multimedia data currently being downloaded;

The client is a terminal device for multimedia data downloading, and the client may be, for example, a mobile phone, a smart phone, a notebook computer, a personal digital assistant (PDA, Personal Digital Assistant), a tablet computer (PAD, Portable Android Device). A mobile terminal such as a portable multimedia player (PMP), and a fixed terminal such as a digital television (TV), a desktop computer, and the like.

The multimedia data is stored on a server for the client to download. The multimedia data includes an index file and a plurality of segment files at different code rates. In an embodiment of the invention, each of the segment files includes a plurality of sub-segment data.

When detecting the change of the network bandwidth, the client determines the first code rate corresponding to the changed network bandwidth according to the downloaded index file, and determines the sub-segment data of the segment file of the multimedia data currently being downloaded. The first code rate is a code rate corresponding to the changed network bandwidth. The description of the use of "first" herein is merely for the purpose of facilitating the description of the present invention, and does not have a specific meaning in itself. For example, the client downloads a segment file at a code rate of 800 kbps, detects that the network changes, and the changed network bandwidth conforms to a code rate of 2000 kbps, and the client downloads a segment file corresponding to a code rate of 2000 kbps.

Step S20, the client monitors the boundary identifier of the determined sub-segment data;

The boundary identifier is a flag in the segment file for determining the range of the sub-segment data. Optionally, the boundary identifier may include a start identifier and an end identifier. In this embodiment, a boundary identifier of the sub-segment data currently being downloaded is an end identifier of the sub-segment data.

Step S30, the client downloads the next sub-segment data of the corresponding segment file in the first code rate from the server when the downloaded data reaches the boundary identifier.

Determining, by the client, the currently downloaded sub-score when the downloaded data reaches the boundary identifier The segment data has been downloaded, and the client downloads the next sub-segment data of the corresponding segment file at the first code rate from the server according to the downloaded index file. The next sub-segment data here is the next sub-segment data corresponding to the sub-segment data that has been downloaded in the order set in the index file. Specifically, for example, when the first sub-sub-segment data download at the 800 kbps code rate is completed, the code rate switching is performed, and the second sub-segment data at the 2000 kbps code rate is downloaded, and the first sub-segment at the 2000 kbps code rate is performed. The segment data corresponds to the first sub-segment data at a code rate of 800 kbps, and only the code rates are different.

As an optional implementation manner, the client may further play the downloaded sub-segment according to the first code rate when the downloading of the next sub-segment data of the corresponding segment file is completed at the first code rate. Segment data.

In this embodiment, when the multimedia data is downloaded, the network bandwidth is monitored. When the network bandwidth is detected to change, the sub-segment data of the segment file of the currently downloaded multimedia data is downloaded, and the code rate can be switched to another code rate. Download the next sub-segment data of the corresponding segment file under another bit rate. You can quickly switch between code rates without waiting for the entire downloaded segment file to be downloaded. At the same time, the corresponding code rate is determined according to the changed network bandwidth, and the multimedia file is downloaded according to the fast switching rate of the network bandwidth, thereby improving the code rate switching efficiency.

Referring to FIG. 2, FIG. 2 is a schematic flowchart diagram of a second embodiment of a multimedia data downloading method according to the present invention. Based on the first embodiment of the foregoing multimedia data downloading method, the step S30 includes:

Step S31, the client calculates a location of the next sub-segment data of the corresponding segment file in the first code rate when the downloaded data reaches the boundary identifier;

When the downloaded data reaches the boundary identifier, the client calculates the location of the next sub-segment data of the corresponding segment file at the first code rate according to the downloaded index file. It should be understood that the location file of each sub-segment data is stored in the index file of the multimedia file. The location information is location information stored by the sub-segment data.

Step S32, the client generates the first request according to the calculated location information;

The client generates the first request according to the calculated location information, to download, from the server, the next sub-segment data of the corresponding segment file in the first code rate. Alternatively, the client may also add the calculated location information to the first request and send a first request containing the location information to the server.

Step S33: The client sends the first request to the server, and receives the next sub-segment data of the corresponding segment file in the first code rate returned by the server.

Sending, by the client, the first request to the server, for the server to return the next sub-segment data of the corresponding segment file at the first code rate when receiving the first request . The client receives sub-segment data returned by the server. Optionally, the server may first send the decoding information corresponding to the next sub-segment file of the corresponding segment file in the first code rate to the client, when the first request is received, and then The corresponding sub-segment data is sent to the client.

In this embodiment, by calculating a location of the next sub-segment data under the corresponding code rate after the network bandwidth changes, a first request is generated according to the location information, and the generated first request is sent to the server to download the corresponding location from the server. The sub-segment data realizes fast switching of the code rate between the sub-segment data according to the network bandwidth, and improves the rate switching efficiency.

Referring to FIG. 3, FIG. 3 is a schematic flowchart diagram of a third embodiment of a multimedia data downloading method according to the present invention. Based on the first embodiment of the foregoing multimedia data downloading method, before the step S10, the method further includes:

Step S11, the client sends a second request to the server to download an index file of the multimedia data from the server;

Step S12, the client receives an index file returned by the server;

Step S13: The client sequentially sends a request to the server according to the index file, and receives each segment file under the second code rate returned by the server.

Included in the index file, the location of the segment file under each code rate of the multimedia file Information, location information of sub-segment data of each segment file, and network bandwidth data corresponding to each code rate. When downloading the multimedia file, the client first sends a second request to the server to download an index file of the multimedia data from the server; the client receives an index file returned by the server; the client The terminal sequentially sends a request to the server according to the index file to sequentially download each segment file of the multimedia file from the server; the client receives each segment under the second code rate returned by the server. File and play at the second rate.

In the embodiment, when downloading the multimedia data, the index file of the multimedia data is first downloaded, and the sub-segment data of each segment file of the multimedia file is sequentially downloaded according to the index file, and the network bandwidth is monitored during the downloading process, and the network bandwidth is detected. When the change occurs, the sub-segment data of the segment file waiting for the currently downloaded multimedia data is downloaded, and then the code rate is switched to another code rate, and the next sub-segment data of the corresponding segment file under another code rate is downloaded. The rate switching can be performed without waiting for all the segment files currently being downloaded to be downloaded. At the same time, the corresponding code rate is determined according to the changed network bandwidth, and the multimedia file is downloaded according to the fast switching rate of the network bandwidth, thereby improving the code rate switching efficiency.

Referring to FIG. 4, FIG. 4 is a schematic flowchart diagram of a fourth embodiment of a multimedia data downloading method according to the present invention. Based on the first embodiment of the foregoing multimedia data downloading method, before the step S11, the method further includes:

Step S100, the server generates an index file and a plurality of segment files according to the multimedia data;

Step S101, the server adds corresponding decoding information at a starting position of each segment file;

Step S102, the server identifies, according to each of the decoding information, sub-segment data that can be code rate switched in the corresponding segment file;

Step S103, the server adds location information of each sub-segment data to the index file. In the piece, when the client downloads the multimedia data, the code rate is switched between the sub-segment data according to the network bandwidth.

The server generates an index file and a plurality of segment files according to the multimedia data; the server adds corresponding decoding information at a starting position of each segment file; the server analyzes each segment file, and decodes according to each The information identifies the sub-segment data that can be code-switched in the corresponding segment file; the server adds the location information of each sub-segment data to the index file, so that the client downloads the multimedia data according to The network bandwidth performs rate switching between sub-segment data.

As an optional implementation manner, when receiving the multimedia data download request of the client, the server sends the corresponding multimedia data to the client according to the received request.

In this embodiment, the server generates the index file and the plurality of segment files by using the multimedia data, and identifies the sub-segment unit that can perform rate switching in the segment file, and adds the location information of each sub-segment unit to the index. In the file. So that when the multimedia data is downloaded, the network bandwidth is monitored. When the network bandwidth is detected to change, the sub-segment data of the segment file of the currently downloaded multimedia data is downloaded, and the code rate can be switched to another code rate. Download the next sub-segment data of the corresponding segment file under another bit rate. The rate switching can be performed without waiting for all the segment files currently being downloaded to be downloaded. At the same time, the corresponding code rate is determined according to the changed network bandwidth, and the multimedia file is downloaded according to the fast switching rate of the network bandwidth, thereby improving the code rate switching efficiency.

The invention further provides a client.

Referring to FIG. 5, FIG. 5 is a schematic diagram of functional modules of a first embodiment of a client according to the present invention.

In this embodiment, the client includes: a determining module 10, a monitoring module 20, and a downloading module 30.

The determining module 10 is configured to determine a first code rate corresponding to the changed network bandwidth when detecting that the network bandwidth changes, and determine a segmented text of the multimedia data currently being downloaded. Sub-segment data of the piece;

The client is a terminal device for multimedia data downloading, and the client may be a mobile terminal such as a mobile phone, a smart phone, a notebook computer, a PDA, a PAD, a PMP, etc., and a digital TV, a desktop computer, or the like. Fixed terminal.

The monitoring module 20 is configured to monitor a boundary identifier of the determined sub-segment data;

The downloading module 30 is configured to download the next sub-segment data of the corresponding segment file in the first code rate from the server when the downloaded data reaches the boundary identifier.

When the downloaded data reaches the boundary identifier, the client determines that the currently downloaded sub-segment data has been downloaded, and the client downloads the corresponding segment at the first code rate from the server according to the downloaded index file. The next sub-segment data of the file. The next sub-segment data here is the next sub-segment data corresponding to the sub-segment data that has been downloaded in the order set in the index file. Specifically, for example, when the first sub-sub-segment data download at the 800 kbps code rate is completed, Perform rate switching to download the second sub-segment data at a rate of 2000 kbps, and the first sub-segment data at a code rate of 2000 kbps corresponds to the first sub-segment data at a code rate of 800 kbps, only the code rate is different. .

As an optional implementation manner, the client may further include a playing module, where the playing module is configured to: when the downloading of the next sub-segment data of the corresponding segment file is completed at the first code rate, according to the The downloaded sub-segment data is played at the first code rate.

In an actual application, the determining module 10, the monitoring module 20, the downloading module 30, and the playing module may all be a central processing unit (CPU), a microprocessor (MPU, a Micro Processor Unit) in the client. Digital signal processor (DSP, Digital Signal Processor), or Field Programmable Gate Array (FPGA) implementation.

Referring to FIG. 6, FIG. 6 is a schematic diagram of functional modules of a second embodiment of a client according to the present invention. The download module 30 includes a computing unit 31, a generating unit 32, and a receiving unit 33, based on the first embodiment of the client;

The calculating unit 31 is configured to calculate, when the downloaded data reaches the boundary identifier, a location of the next sub-segment data of the corresponding segment file in the first code rate;

The generating unit 32 is configured to generate the first request according to the calculated location information;

The receiving unit 33 is configured to send the first request to the server, and receive the next sub-segment data of the corresponding segment file in the first code rate returned by the server.

In practical applications, the computing unit 31, the generating unit 32, and the receiving unit 33 can all be implemented by a CPU, an MPU, a DSP, an FPGA, or the like in the client.

In an embodiment, the downloading module 30 is further configured to send a second request to the server to download an index file of the multimedia data from the server;

The downloading module 30 is further configured to receive an index file returned by the server;

The downloading module 30 is further configured to sequentially send a request to the server according to the index file, and receive each segment file under the second code rate returned by the server.

The index file includes location information of the segment file at each bit rate of the multimedia file, location information of the sub-segment data of each segment file, and network bandwidth data corresponding to each code rate. When downloading the multimedia file, the client first sends a second request to the server to download an index file of the multimedia data from the server; the client receives an index file returned by the server; the client The terminal sequentially sends a request to the server according to the index file to sequentially download each segment file of the multimedia file from the server; the client receives each segment under the second code rate returned by the server. File and play at the second rate.

The invention further provides a server.

Referring to FIG. 7, FIG. 7 is a schematic diagram of functional modules of a preferred embodiment of a server according to the present invention.

In this embodiment, the server includes: a generating module 100, an adding module 101, and an identifying module 103;

The generating module 100 is configured to generate an index file and a plurality of segment files according to the multimedia data;

The adding module 101 is configured to add corresponding decoding information at a starting position of each segment file;

The identifier module 102 is configured to identify a corresponding segment file according to each of the decoding information. Sub-segment data in which rate switching can be performed;

The adding module 102 is further configured to add location information of each sub-segment data to the index file, so that when the client downloads the multimedia data, the code rate is switched between the sub-segment data according to the network bandwidth. .

As an optional implementation manner, the server may further include a sending module, where the sending module is configured to: when receiving the multimedia data download request of the client, send the corresponding multimedia data to the client according to the received request. end.

In an actual application, the generating module 100, the adding module 101, and the identifying module 103 can be implemented by a CPU, an MPU, a DSP, an FPGA, or the like located in the server. The sending module further included in the server may be implemented by a transceiver antenna.

The invention further provides a multimedia data downloading system.

Referring to FIG. 8, FIG. 8 is a schematic diagram of functional modules of a multimedia data download system according to a preferred embodiment of the present invention.

In this embodiment, the multimedia data download system includes a client as described above and a server as described above. The specific features of the client and the server are referred to the foregoing embodiments. Since all the technical solutions of all the foregoing embodiments are used in the present multimedia data, at least all the beneficial effects brought by the technical solutions of the foregoing embodiments are provided. I will not repeat them one by one.

The embodiment of the invention further describes a computer storage medium, wherein the computer storage medium stores computer executable instructions, and the computer executable instructions are used to execute the multimedia data downloading method described in the foregoing embodiments.

It is to be understood that the term "comprises", "comprising", or any other variants thereof, is intended to encompass a non-exclusive inclusion, such that a process, method, article, or device comprising a series of elements includes those elements. It also includes other elements that are not explicitly listed, or elements that are inherent to such a process, method, article, or device. An element that is defined by the phrase "comprising a ..." does not exclude the presence of additional equivalent elements in the process, method, item, or device that comprises the element.

The serial numbers of the embodiments of the present invention are merely for the description, and do not represent the advantages and disadvantages of the embodiments.

Through the description of the above embodiments, those skilled in the art can clearly understand that the foregoing embodiment method can be implemented by means of software plus a necessary general hardware platform, and of course, can also be through hardware, but in many cases, the former is better. Implementation. Based on such understanding, the technical solution of the present invention, which is essential or contributes to the prior art, may be embodied in the form of a software product stored in a storage medium (such as ROM/RAM, disk, The optical disc includes a number of instructions for causing a terminal device (which may be a cell phone, a computer, a server, an air conditioner, or a network device, etc.) to perform the methods described in various embodiments of the present invention.

The above are only the preferred embodiments of the present invention, and are not intended to limit the scope of the invention, and the equivalent structure or equivalent process transformations made by the description of the present invention and the drawings are directly or indirectly applied to other related technical fields. The same is included in the scope of patent protection of the present invention.

Industrial applicability

In the embodiment of the present invention, when the multimedia data is downloaded, the network bandwidth is monitored. When the network bandwidth is detected to change, the sub-segment data of the segment file of the currently downloaded multimedia data is downloaded, and the switch can be switched to another. One bit rate, download the next sub-segment data of the corresponding segment file under another bit rate, so that the code rate switching can be quickly performed without waiting for all the segment files currently being downloaded to be completely downloaded; The network bandwidth determines the corresponding code rate, and the multimedia file is downloaded according to the fast switching rate of the network bandwidth, thereby improving the rate switching efficiency.

Claims

A multimedia data downloading method, the method comprising:

When detecting that the network bandwidth changes, the client determines a first code rate corresponding to the changed network bandwidth, and determines sub-segment data of the segment file of the multimedia data currently being downloaded;

The client monitors the boundary identifier of the determined sub-segment data;

When the downloaded data reaches the boundary identifier, the client downloads the next sub-segment data of the corresponding segment file at the first code rate from the server.
The multimedia data downloading method according to claim 1, wherein the client downloads the next sub-segment data of the corresponding segment file at the first code rate from the server when the downloaded data reaches the boundary identifier The steps include:

When the downloaded data reaches the boundary identifier, the client calculates a location of the next sub-segment data of the corresponding segment file in the first code rate;

The client generates the first request according to the calculated location information;

The client sends the first request to the server, and receives the next sub-segment data of the corresponding segment file under the first code rate returned by the server.
The multimedia data downloading method according to claim 1, wherein the client determines a first code rate corresponding to the changed network bandwidth when detecting a change in the network bandwidth, and determines a score of the multimedia data currently being downloaded. Before the step of sub-segment data of the segment file, it also includes:

Sending, by the client, a second request to the server, to download an index file of the multimedia data from the server;

The client receives an index file returned by the server;

The client sequentially sends a request to the server according to the index file, and receives each segment file under the second code rate returned by the server.
The multimedia data downloading method according to any one of claims 1 to 3, wherein After the step of downloading, by the server, the next sub-segment data of the corresponding segment file in the first code rate, the method further includes:

When the client downloads the next sub-segment data corresponding to the segment file at the first code rate, the client plays the downloaded sub-segment data according to the first code rate.
The multimedia data downloading method according to claim 3, wherein before the step of the client transmitting the second request to the server to download the index file of the multimedia data from the server, the method further comprises:

The server generates an index file and a plurality of segment files according to the multimedia data;

The server adds corresponding decoding information at a starting position of each segment file;

Determining, by the server, the sub-segment data that can be code rate switched in the corresponding segment file according to each of the decoding information;

The server adds the location information of each sub-segment data to the index file, so that the client performs rate switching between the sub-segment data according to the network bandwidth when the client downloads the multimedia data.
A client, the client comprising:

a determining module, configured to determine a first code rate corresponding to the changed network bandwidth when detecting a change in network bandwidth, and determine sub-segment data of the segment file of the multimedia data currently being downloaded;

a monitoring module configured to monitor a boundary identifier of the determined sub-segment data;

And a downloading module, configured to download the next sub-segment data of the corresponding segment file in the first code rate from the server when the downloaded data reaches the boundary identifier.
The client of claim 6, wherein the downloading module comprises a computing unit, a generating unit, and a receiving unit;

a calculating unit, configured to calculate, when the downloaded data reaches the boundary identifier, a location of a next sub-segment data of the corresponding segment file in the first code rate;

a generating unit, configured to generate the first request according to the calculated location information;

The receiving unit is configured to send the first request to the server, and receive the next sub-segment data of the corresponding segment file in the first code rate returned by the server.
The client according to claim 6, wherein the downloading module is further configured to send a second request to the server to download an index file of the multimedia data from the server;

The downloading module is further configured to receive an index file returned by the server;

The downloading module is further configured to sequentially send a request to the server according to the index file, and receive each segment file under the second code rate returned by the server.
The client of claim 6, wherein the client further comprises a play module;

The playing module is configured to play the downloaded sub-segment data according to the first code rate when the downloading of the next sub-segment data of the corresponding segment file is completed at the first code rate.
A server, the server comprising:

Generating a module, configured to generate an index file and a plurality of segment files according to the multimedia data;

Adding a module, configured to add corresponding decoding information at a starting position of each segment file;

The identifier module is configured to identify, according to each of the decoding information, sub-segment data that can be code rate switched in the corresponding segment file;

The adding module is further configured to add location information of each sub-segment data to the index file, so that when the client downloads the multimedia data, the rate switching is performed between the sub-segment data according to the network bandwidth.
A multimedia data downloading system, the multimedia data downloading system comprising the client according to any one of claims 6 to 9 and the server according to claim 10.
A computer storage medium having stored therein computer executable instructions for performing the method of any one of claims 1 to 5.