WO2009059499A1

WO2009059499A1 - Method and system for processing the time-shifting of iptv

Info

Publication number: WO2009059499A1
Application number: PCT/CN2008/070881
Authority: WO
Inventors: Jinchun Yang
Original assignee: Huawei Technologies Co., Ltd.
Priority date: 2007-11-07
Filing date: 2008-05-05
Publication date: 2009-05-14
Also published as: CN101431657A; CN101431657B

Abstract

A method for processing the time-shifting of IPTV includes the steps of: receiving the play command of the user terminal after time-shifting occurs; adjusting the unicast transmission rate to the user terminal based on the play command of the user terminal so that the unicast transmission course is consistent with the multicast transmission course of the server after the unicast transmission is carried out for a period of time; transmitting the media stream corresponding to the play command to the user terminal through the unicast transmission; switching to the multicast transmission to transmit the media stream corresponding to the play command, when the unicast transmission course is consistent with the multicast transmission course. According to the embodiment of the invention, it is possible to adjust the unicast transmission rate of the server to the user through analyzing the play action of the user after the time-shifting state so as to make the unicast transmitted media stream to be consistent with the multicast transmitted media stream gradually, so that the unicast transmission channel will be deleted finally so as to achieve the aim of saving bandwidth.

Description

Network television time shift processing method and system

Technical field

The present invention relates to the field of communication technologies, and in particular, to a network television time shift processing method and system. Background technique

In the ever-changing development of communication technology, IPTV (Internet TV) has gradually penetrated into the lives of the people. IPTV is an interactive network TV. It is a brand-new technology that uses broadband cable TV networks to integrate Internet, multimedia, and communication technologies to provide home users with a variety of interactive services, including digital TV. Users can enjoy IPTV services in two ways at home: computer or network set-top box + regular TV. It can adapt well to the rapid development of today's networks and make full and effective use of network resources. IPTV is different from traditional analog cable TV and is not the same as classic digital TV. Because traditional and classic digital TVs have the characteristics of frequency division, timing, and one-way broadcasting. Although classic digital TV has many technological innovations compared to analog TV, it is only a change in signal form without touching the media content. Propagation mode. IPTV is an infrastructure that utilizes broadband cable television networks, with home televisions as the primary terminal appliances, and a variety of digital media services, including television programming, through Internet Protocol. Therefore, IPTV is a brand-new business form. It is a converged service integrating traditional TV programs, Internet information services and value-added services. It is also the real entry point for future digital homes. With its development, users will gradually recognize the IPTV platform as an entertainment and service center for their future home business. The architecture of IPTV itself also determines that it must develop in this direction.

In the IPTV service, in order to ensure a certain definition, the media content is usually compression-encoded, but the encoded media code rate is still high. In order to save transmission bandwidth, the media stream is implemented by multicast technology transmission. However, when watching IPTV, users sometimes pause, rewind, etc., and then press play to continue watching. In order to maintain the continuity of the user's viewing, in the IPTV system, the user's behavior is treated as a "time shift" operation. The prior art time shift operation is: Prepare a set of files for on-demand, the content is consistent with the live content. The user who normally views the live content receives the program transmitted through the multicast technology. When the user requests the time shift, the system converts the user's request into an on-demand request for accessing the specific location of the file. The system finds the corresponding location in the media file according to the breakpoint information in the user request, and transmits the subsequent program stream to the user in a unicast technology.

Regarding the method for realizing IPTV time shift, the following methods are available in the prior art: After the user shifts time, the server continuously transmits through the unicast technology. Subsequent user operations are for on-demand files, which means that the server needs to establish a unicast transport channel for each time-shifted user terminal. The disadvantage of this method is that as the number of time-shifted users increases, the system bandwidth consumption also increases, and system performance will be greatly reduced. Summary of the invention

The main purpose of the present invention is to provide a network TV time shift processing method and system, which can automatically automatically switch users to multicast play without user intervention, and solve the problem of long-term unicast continuous transmission in the prior art. This leads to technical defects in system bandwidth consumption and system performance degradation.

An embodiment of the present invention provides a network television time shift processing method, including the following steps: receiving a play command of a user terminal after a time shift occurs; and adjusting a unicast transmission rate of the user terminal according to a play command of the user terminal, The unicast transmission process can be consistent with the multicast transmission process of the server after the unicast transmission for a certain period of time; the media stream corresponding to the play command is transmitted to the user terminal by unicast; when the unicast transmission process and the unicast transmission process When the multicast transmission process is consistent, the media stream corresponding to the play command is switched to multicast for transmission.

The embodiment of the present invention further provides a network television time shift processing system, including a server and at least one user terminal, where the user terminal is configured to send a play command to the server, and the server is configured to adjust according to the play command. The unicast transmission rate of the user terminal is such that the unicast transmission process can be consistent with the multicast transmission process of the server after being transmitted for a certain time by unicast, and simultaneously Transmitting, by the unicast, the media stream corresponding to the play command to the user terminal, and switching the media stream corresponding to the play command when the unicast transmission process of the user terminal is consistent with the multicast transmission process Transfer to multicast.

The embodiment of the present invention further provides a network television time shift processing server, including a command receiving module, a unicast playback processing module, and a multicast switching module, where the command receiving module is configured to receive a play command of a user terminal that has a time shift; The unicast playback processing module is configured to adjust a unicast transmission rate to the user terminal according to the play command, so that the unicast transmission process can be consistent with the multicast transmission process of the server after being transmitted by using unicast for a certain period of time And transmitting the media stream requested by the user terminal to the user terminal by using a unicast; the multicast switching module, configured to: when the unicast transmission process is consistent with the multicast transmission process, The media stream corresponding to the play command is switched to multicast for transmission. DRAWINGS

1 is a flowchart of a method for processing time shift of a network television according to Embodiment 1 of the present invention;

2 is a flowchart of a method for processing time shift of a network television according to Embodiment 2 of the present invention;

FIG. 3 is a structural diagram of a network television time shift processing system according to an embodiment of the present invention. detailed description

The embodiment of the present invention is further described in detail with reference to the accompanying drawings and embodiments. FIG. 1 is a flowchart of a network television time shift processing method according to Embodiment 1 of the present invention, which can be based on a user terminal in this embodiment. The command combination determines the corresponding rate adjustment policy, and adjusts the current unicast transmission rate according to the rate adjustment policy, so that it can be consistent with the multicast transmission rate as soon as possible, thereby switching to multicast for transmission. For example, if the user presses the play button after pressing the pause button, the user's transmission rate is appropriately increased to be consistent with the multicast, and the real-time delivery is performed. The user terminal may be a terminal device capable of IPTV playback, such as an STB (Set Top Box), a mobile phone, or a PC terminal. This embodiment includes the following steps: Step S101: The user terminal sends a request command to the server, and the server returns a response to the request command, and correspondingly transmits the media requested by the user terminal to the user terminal.

Step S102: After receiving the command that the user terminal pauses, rewinds, or drags to enter the time shift state, the server determines that the user terminal has a time shift.

Step S103: The server receives a play command of the time shifting user terminal. In order to facilitate the understanding of the embodiment, the commands in the IPTV are described below. The common protocol for requesting and responding to the IPTV is the RTSP protocol. RTSP consists of a message header and a message body. In addition to defining the command name, the message header defines some attributes related to the command. In the RTSP protocol, the pause is implemented by the RTSP-PAUSE command; the playback is implemented by the RTSP-PLAY command, and the Scale attribute of the command message is 1; the fast rewind operation can also be implemented by the RTSP-PLAY command, but the Scale attribute of the command message is one. A non-zero rational number, such as Scale=-3.5, indicates that the user terminal is required to rewind 3.5 times relative to the normal playback speed.

Step S1Q4, the server determines whether the play command is a play command after a command that causes a time shift state, such as pause, rewind, or post drag, to determine whether the RTSP-PLAY command is received after step S102. If the normal play command received by the server is after a pause, forward or backward drag command that causes the time shift status to be entered, then the server defaults to the need to adjust the unicast transmission rate so that the unicast transmission process is transmitted after unicast for a certain period of time. It can be consistent with the multicast transmission process of the server.

Step S105, since the fast rewind operation can also be implemented by the RTSP_PLAY command, it is also required to detect whether the Scale parameter is 1 after receiving the RTSP-PLAY command. If the Scale parameter is not 1, it means that the user may press the "fast forward" or "rewind" button, the system will process it in the media server's default processing mode. When the Scale parameter is 1, the system modifies the Scale value with a preset policy.

Step S106, if it is a play command after the pause command and the Scale value is 1, the corresponding rate adjustment policy is determined according to the play command of the user terminal. As a preferred embodiment, the rate adjustment strategy proposed by the present invention is as follows:

Table 1 Unicast Play Rate Adjustment Strategy Rate adjustment

Features

Strategy

Server at normal speed

Normal double speed RTSP — PLAY command Sca le=l Play media content

Broadcast the RTSP-PLAY command at a constant speed for pre-fast playback

Put, the playback speed is a reasonable number of reasonable numbers.

Unicast playback speed: RTSP-PLAY The Sca le parameter in a preset time is: Smart Acceleration

Catch up to multicast playback 1 + (current multicast media frame number - current unicast media frame number) / single frame playback time step S107, modify the Sca le value according to the preset rate adjustment policy, thereby guiding unicast to preset The rate adjustment policy is quickly played, and the media stream requested by the user terminal is transmitted to the user terminal through unicast. For example, if the rate adjustment policy is fast playback, and the Sca le value is 1. 5 , the unicast will play at a speed of 1. 5 times, and the Sca le value is set to not affect the user's viewing.

Step S108: When the unicast transmission process is consistent with the multicast transmission process of the server, the server switches the media stream corresponding to the play command to multicast for transmission, and deletes the unicast transmission channel.

According to the foregoing embodiment, the unicast can be quickly played according to the normal play command input by the user, and when the unicast play catches up with the multicast play, the media stream is switched to the multicast for transmission, and the unicast transport channel is deleted, thereby achieving Save bandwidth.

Compared with the prior art, the embodiment of the present invention can determine whether the unicast transmission rate needs to be adjusted according to the normal play command by parsing the normal play command of the user after the time shift state, so that the user can watch the broadcast without affecting the user's viewing. In this case, the media stream that is transmitted can be gradually consistent with the multicast transmission, thereby finally deleting the unicast transmission channel, thereby saving bandwidth and optimizing system performance.

FIG. 2 is a flowchart of a network television time shift processing method according to Embodiment 2 of the present invention. In this embodiment, the manner in which the multicast group is sent by the carousel server is used to select the multicast group whose playing time is closest to the user terminal to join, so that the time for the user to play the unicast is the shortest, and thus the user is generated. The impact is also minimal.

Step S201: The carousel server sends the same media to different multicast groups at regular time intervals. Body content, and a multicast link for each multicast group. However, for the user, the server only provides a media link for the user for a specific media. After clicking the media link, the server selects which multicast group the user should join, and then the multicast link corresponding to the multicast group. Access is made.

Step S202: The server receives a play command of the user terminal that is time-shifted. Since the user terminal has time-shifted during playback, it cannot be consistent with the multicast that is normally played. Therefore, the server needs to transmit the media requested by the user terminal to the user through unicast.

Step S203: The server selects a multicast group that is closest to the time when the user terminal sends the play command according to the time when the user terminal sends the play command. As an embodiment of the present invention, the specific time is: the server reads the current time t of receiving the user play command, and searches for the start time T of the closest multicast group, wherein the search time T of the corresponding multicast group is preferably used to quickly find Algorithms are performed, such as dichotomy. Calculate the difference between the start time T and the current time t of the received command, such as calculating min | t-T |. Therefore, the corresponding closest multicast group is determined according to the minimum value of the difference between the broadcast time T and the current time t of the received command.

Step S204: The server sets a corresponding rate adjustment policy according to the time when the play command is sent and the multicast group play time difference. Also in this embodiment the rate adjustment strategy can be normal speed, fast play or smart play. By setting the rate adjustment policy, the unicast transmission process can be consistent with the multicast transmission process of the server after a certain time of transmission by unicast.

Step S205: Set a Sca l e value of the RTSP-PLAY command according to the rate adjustment policy. Specifically, firstly, according to the difference between the multicast group broadcast time T and the current time t of the received command, if it is determined that tT is positive, the user play time is earlier than the determined multicast group start time, so Sca le is set. If the tT is negative, the user playback time is later than the determined multicast group start time. Therefore, setting Sca le to a positive number speeds up the playback speed.

Step S206: The server adjusts the playback speed of the unicast according to the Sca l e value corresponding to the current user RTSP_PLAY command, and transmits the media stream requested by the user terminal to the user terminal by using unicast.

Step S207: When the unicast transmission process is consistent with the multicast transmission process of the multicast group, the service The device will switch the media stream of the user terminal to the multicast group selected by the server, and delete the unicast transmission channel.

The foregoing embodiment of the present invention selects the closest multicast group for the user requesting to play, and adjusts the unicast playback speed according to the time difference between the multicast group and the current user request, thereby enabling unicast without user intervention. Playback can be consistent with multicast playback, and when unicast playback can be consistent with multicast playback, the media stream is switched to multicast for transmission, and the unicast transmission channel is deleted, thereby achieving bandwidth saving.

As shown in FIG. 3, it is a structural diagram of a network television time shift processing system according to an embodiment of the present invention. The system includes a server 1 and at least one user terminal 2, and the user terminal 2 is configured to send a play command to the server 1, where the user terminal 2 can It is a terminal device capable of performing IPTV playback, such as an STB, a mobile phone, or a PC terminal; the server 1 is configured to adjust a unicast transmission rate to the user terminal 2 according to a play command sent by the user terminal 2, so that unicast transmission after a certain time is transmitted through unicast The process can be consistent with the multicast transmission process of the server 1, and the media stream corresponding to the play command is transmitted to the user terminal 2 through unicast, and when the unicast transmission process of the user terminal 2 is consistent with the multicast transmission process, The media stream corresponding to the play command is switched to multicast for transmission.

The server 1 includes a command receiving module 11, a unicast playback processing module 12, and a multicast switching module 13. The command receiving module 1 1 is configured to receive a play command of the user terminal 2 that occurs when the time shift occurs. The unicast play processing module 12 is configured to adjust the play command according to the play command received by the command receiving module 11 after the command receiving module 11 receives the play command. The unicast transmission rate of the user terminal 2 is such that the unicast transmission process can be consistent with the multicast transmission process of the server 1 after the unicast transmission for a certain period of time, and the media stream requested by the user terminal 2 is transmitted to the user terminal 2 by unicast; The multicast switching module 13 is configured to switch the media stream corresponding to the play command to multicast for transmission when the unicast transmission process is consistent with the multicast transmission process of the server 1.

The unicast playback processing module 12 includes a judging sub-module 121 and a rate adjustment policy determining sub-module 122, and the judging sub-module 121 is configured to determine whether the play command is in a time-shift state caused by pause, rewind, or drag. Normal play command after command; rate adjustment strategy determines submodule The block 122 is configured to determine, according to the play command of the user terminal 2, a corresponding rate adjustment policy, and adjust the time shift user according to the rate adjustment policy, when the determining submodule 121 determines that the play command is after the command that causes the time shift state to be entered. The unicast transmission rate of the terminal 2 enables the unicast transmission process to be consistent with the multicast transmission process of the server 1 after being transmitted for a certain time by unicast.

The server 1 further includes a carousel server module 14 for transmitting the same media stream to different multicast groups at regular time intervals.

The unicast playback processing module 12 includes a multicast group determining sub-module 123 and a rate adjustment policy setting sub-module 124, and the multicast group determining sub-module 123 is configured to select a multicast that has the closest start time to the user terminal 2 to send the play command time. The rate adjustment policy setting sub-module 124 sets the rate adjustment policy according to the playing time of the selected multicast group and the receiving time of the play command, and adjusts the unicast transmission rate to the user terminal 2.

The server 1 further includes a unicast channel deletion module 15 for deleting the unicast transmission channel after the multicast switching module 13 transfers the media stream of the user terminal 2 to the multicast.

Through the network television time shift processing system of the above embodiment, the normal play command input by the user can determine whether the unicast transmission rate needs to be adjusted according to the normal play command, so that it can be quickly and without affecting the user's viewing. The multicast is consistent, which removes the unicast transport channel and saves bandwidth.

A person skilled in the art can understand that all or part of the steps of implementing the above method embodiments may be completed by using hardware related to program instructions, and the foregoing program may be stored in a computer readable storage medium, and the program is executed when executed. The steps of the foregoing method embodiments are included; and the foregoing storage medium includes: a medium that can store program codes, such as a ROM, a RAM, a magnetic disk, or an optical disk.

Through the above description of the embodiments, those skilled in the art can clearly understand that the present invention 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, including a plurality of instructions for making a Taiwan A computer device (which may be a personal computer, server, or network device, etc.) performs the methods described in various embodiments of the present invention.

The above disclosure is only a few specific embodiments of the present invention, but the present invention is not limited thereto, and any changes that can be considered by those skilled in the art should fall within the protection scope of the present invention.

Claims

Rights request

A network television time shift processing method, characterized in that the method comprises the following steps:

Receiving a play command of the user terminal after the time shift occurs;

Adjusting a unicast transmission rate to the user terminal according to a play command of the user terminal, so that the unicast transmission process can be consistent with the multicast transmission process of the server after being transmitted by unicast for a certain period of time;

Transmitting, by the unicast, the media stream corresponding to the play command to the user terminal;

When the unicast transmission process is consistent with the multicast transmission process, the media stream corresponding to the play command is switched to multicast for transmission.

The network television time shift processing method according to claim 1, wherein the adjusting the unicast transmission rate of the user terminal according to the play command of the user terminal, specifically: a play command;

If the play command is a normal play command after the command that causes the time shift state to be entered, the rate adjustment policy is applied according to the play command of the user terminal;

Adjusting a unicast transmission rate of the user terminal according to the rate adjustment policy.

The network television time shift processing method according to claim 1, wherein the unicast transmission rate of the user terminal is adjusted according to a play command of the user terminal:

Selecting, for the user terminal, a multicast group whose startup time is closest to the time when the user terminal sends the play command time;

Setting a rate adjustment policy according to a time difference between the time when the play command is sent and the start time of the multicast group start transmission;

Adjusting a unicast transmission rate to the user terminal according to the rate adjustment policy;

The media stream corresponding to the play command is switched to multicast for transmission, where the media stream corresponding to the play command is switched to the selected multicast group for transmission.

The network television time shift processing method according to claim 2 or 3, wherein The rate adjustment strategy includes one or more of normal double speed, fast play, slow play, or smart play.

The network television time shift processing method according to claim 1, wherein after the media stream corresponding to the play command is switched to multicast for transmission, the method further comprises: deleting the unicast transmission channel.

A network television time shift processing system, comprising: a server, configured to receive a play command capable of processing a user terminal;

The user terminal is configured to send a play command to the server;

The server is configured to adjust a unicast transmission rate to the user terminal according to the play command, so that the unicast transmission process can be consistent with the multicast transmission process of the server after being transmitted for a certain time by using unicast, and The media stream corresponding to the play command is transmitted to the user terminal by using a unicast, and when the unicast transmission process of the user terminal is consistent with the multicast transmission process, the media stream corresponding to the play command is switched to the group. Broadcast for transmission.

A network television time shift processing server, comprising: a command receiving module, a unicast playback processing module, and a multicast switching module,

The command receiving module is configured to receive a play command of the user terminal that is time-shifted; the unicast play processing module is configured to adjust a unicast transmission rate to the user terminal according to the play command, so that the unicast transmission rate is After being transmitted for a certain period of time, the unicast transmission process can be consistent with the multicast transmission process of the server, and the media stream requested by the user terminal is transmitted to the user terminal by unicast;

The multicast switching module is configured to switch the media stream corresponding to the play command to multicast for transmission when the unicast transmission process is consistent with the multicast transmission process.

The network television time shift processing server according to claim 7, wherein the unicast playback processing module comprises a determining submodule and a rate adjustment policy determining submodule,

The determining submodule is configured to determine whether the play command is a normal play command after a command that causes a time shift state to be entered; The rate adjustment policy determining submodule is configured to determine, according to a play command of the user terminal, a corresponding rate adjustment policy, according to the play command after the determining submodule determines that the command is to enter the time shift state, and according to the play command The rate adjustment policy adjusts a unicast transmission rate of the time-shifted user terminal.

The network television time-shift processing server according to claim 7, further comprising a carousel server module, configured to send the same media stream to different multicast groups at fixed time intervals.

The network television time-shift processing server according to claim 9, wherein the unicast playback processing module comprises a multicast group determining sub-module and a rate adjustment policy setting sub-module, and the multicast group determining sub-module And selecting a multicast group whose startup time is closest to the time when the user terminal sends the play command;

The rate adjustment policy setting sub-module sets the rate adjustment policy according to the play time of the selected multicast group and the receiving time of the play command, and adjusts the unicast transmission rate to the user terminal according to the rate adjustment policy. .

The network television time-shift processing server according to claim 7, further comprising a unicast channel deletion module, configured to switch, by the multicast switching module, the media stream corresponding to the play command to multicast After the transmission, the unicast transmission channel is deleted.

12. A computer readable storage medium, characterized in that the computer readable storage medium stores computer program code that can be implemented when the computer program code is executed by a computer:

Receiving a play command of the user terminal after the time shift occurs;