CN113852856B - Method for fast switching channels - Google Patents
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- CN113852856B CN113852856B CN202111249537.8A CN202111249537A CN113852856B CN 113852856 B CN113852856 B CN 113852856B CN 202111249537 A CN202111249537 A CN 202111249537A CN 113852856 B CN113852856 B CN 113852856B
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- 238000000034 method Methods 0.000 title claims abstract description 20
- 239000000284 extract Substances 0.000 claims description 5
- 238000010586 diagram Methods 0.000 description 5
- 230000005540 biological transmission Effects 0.000 description 1
- 230000002708 enhancing effect Effects 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000007781 pre-processing Methods 0.000 description 1
- 238000006467 substitution reaction Methods 0.000 description 1
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Classifications
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
- H04N21/00—Selective content distribution, e.g. interactive television or video on demand [VOD]
- H04N21/40—Client devices specifically adapted for the reception of or interaction with content, e.g. set-top-box [STB]; Operations thereof
- H04N21/43—Processing of content or additional data, e.g. demultiplexing additional data from a digital video stream; Elementary client operations, e.g. monitoring of home network or synchronising decoder's clock; Client middleware
- H04N21/438—Interfacing the downstream path of the transmission network originating from a server, e.g. retrieving encoded video stream packets from an IP network
- H04N21/4383—Accessing a communication channel
- H04N21/4384—Accessing a communication channel involving operations to reduce the access time, e.g. fast-tuning for reducing channel switching latency
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
- H04N21/00—Selective content distribution, e.g. interactive television or video on demand [VOD]
- H04N21/20—Servers specifically adapted for the distribution of content, e.g. VOD servers; Operations thereof
- H04N21/23—Processing of content or additional data; Elementary server operations; Server middleware
- H04N21/231—Content storage operation, e.g. caching movies for short term storage, replicating data over plural servers, prioritizing data for deletion
- H04N21/23106—Content storage operation, e.g. caching movies for short term storage, replicating data over plural servers, prioritizing data for deletion involving caching operations
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
- H04N21/00—Selective content distribution, e.g. interactive television or video on demand [VOD]
- H04N21/20—Servers specifically adapted for the distribution of content, e.g. VOD servers; Operations thereof
- H04N21/23—Processing of content or additional data; Elementary server operations; Server middleware
- H04N21/231—Content storage operation, e.g. caching movies for short term storage, replicating data over plural servers, prioritizing data for deletion
- H04N21/23116—Content storage operation, e.g. caching movies for short term storage, replicating data over plural servers, prioritizing data for deletion involving data replication, e.g. over plural servers
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
- H04N21/00—Selective content distribution, e.g. interactive television or video on demand [VOD]
- H04N21/60—Network structure or processes for video distribution between server and client or between remote clients; Control signalling between clients, server and network components; Transmission of management data between server and client, e.g. sending from server to client commands for recording incoming content stream; Communication details between server and client
- H04N21/63—Control signaling related to video distribution between client, server and network components; Network processes for video distribution between server and clients or between remote clients, e.g. transmitting basic layer and enhancement layers over different transmission paths, setting up a peer-to-peer communication via Internet between remote STB's; Communication protocols; Addressing
- H04N21/64—Addressing
- H04N21/6405—Multicasting
Landscapes
- Engineering & Computer Science (AREA)
- Multimedia (AREA)
- Signal Processing (AREA)
- Two-Way Televisions, Distribution Of Moving Picture Or The Like (AREA)
- Data Exchanges In Wide-Area Networks (AREA)
Abstract
The invention relates to a method and a system for rapidly switching channels, comprising the following steps: the multicast fast-cutting cache server synchronizes and caches video data streams in a plurality of multicast servers in real time, the I-frame information multicast server receives I-frame information extracted from video stream data from each multicast server, the I-frame information of each multicast server is spliced end to end and then forwarded to the set top box in real time, when the set top box receives a channel switching request, the time of the next I-frame of a multicast channel to be added is analyzed from the I-frame information, and according to the relation between the time of the next I-frame and a threshold value, whether the multicast server is directly requested to be added or the multicast fast-cutting cache server is firstly requested to be requested to unicast data streams, and then the multicast server is requested to be added. The invention can effectively reduce the concurrent request quantity of the multicast fast-cutting cache server, quicken the channel switching speed, improve the picture quality and improve the user multicast viewing experience.
Description
Technical Field
The invention relates to the field of Internet, in particular to a method and a system for rapidly switching channels in IPTV.
Background
Multicast is an important component of IPTV service, multicast channel switching has long been a technical difficulty in the field of multicast, and the length of the channel switching delay and the smoothness of playing are very critical factors affecting user experience.
In the prior art, in order to speed up channel switching, a measure is taken to enable a multicast fast-switching cache server (FCC server) to cache a section of code stream starting with an I frame.
As shown in fig. 1, the prior art fast-cutting system includes an FCC server, a set of 1 to N multicast servers, and an IPTV set-top box, wherein the IPTV set-top box includes a player and a browser. When the channel is switched, the code stream of the FCC server is firstly obtained, so that a section of code stream starting with the I frame is obtained, and therefore, the time for waiting for the I frame to arrive is not needed, and the channel switching time can be reduced.
For example, in the scheme in CN111093090a, a multicast fast-cut buffer server receives a source multicast signal, performs preprocessing on the received multicast channel data, identifies an I frame start position, stores video data, and manages the video data. Based on the real-time I frame information flow, the method dynamically judges whether the quick channel switching server is needed to be used, and based on the pretreatment of the I frame data, the storage, inquiry and issuing efficiency of the quick channel switching server is improved.
For another example, in the CN 109982098B, when receiving the original channel list information sent by the IPTV server, the method performs preloading on the original channel list information to obtain an available live address, a TS stream rate, whether to support fast streaming, and constructs a custom channel list. The fast channel switching is based on a customized channel list at the set top box side, and based on an I-frame information stream, the list is updated and judged in real time every time the channel is switched.
However, in these existing modes, the set top box enables the FCC server by default, which consumes more resources for the FCC server (CDN content delivery network), and even in a high concurrency situation, the FCC server may not respond, which results in an increase of the user channel switching delay and affects the user viewing experience.
Accordingly, there is a need for a more efficient method and system for fast channel switching that reduces the number of concurrent requests from an FCC server.
Disclosure of Invention
This summary is provided to introduce a selection of concepts in a simplified form that are further described below in the detailed description. This summary is not intended to identify key features or essential features of the claimed subject matter; nor is it intended to be used to determine or limit the scope of the claimed subject matter.
The system for rapidly switching channels of the invention comprises: a plurality of multicast servers; a multicast fast-cutting cache server communicatively connected to the plurality of multicast servers; a set top box communicatively connected to the plurality of multicast servers and the multicast fast-cutting cache server; and the I-frame information multicast server is respectively connected with the multicast servers and the set top box in a communication way.
The multicast servers synchronize and cache the video data streams in real time to the multicast fast-cutting cache server, and extract I-frame information from the video stream data and send the I-frame information to the I-frame information multicast server, wherein the I-frame information comprises a start mark, a multicast channel number, the arrival time of the next I-frame of the multicast channel, the sequence number of the next I-frame of the multicast channel and a termination mark.
The I frame information multicast servers receive I frame information of each multicast server, the I frame information is carried by using UDP protocol to form an I frame information stream, the I frame information stream is composed of an IP header and UDP user datagram, wherein the UDP user datagram comprises the UDP header and I frame information data formed by head-to-tail splicing of the I frame information of each multicast server, and the I frame information stream is forwarded to the set top box in real time.
The set top box comprises a player module, when the set top box receives a channel switching request, the time of the next I frame of a multicast channel to be added is analyzed from I frame information, when the time of the next I frame is judged to be smaller than or equal to a threshold value, the multicast server is directly requested to be added, when the time of the next I frame is judged to be larger than the threshold value, unicast data streams are requested to the multicast fast-cutting cache server, and then the multicast server is requested to be added.
The method for rapidly switching channels in IPTV of the present invention comprises: synchronizing video data streams in each multicast server in real time and caching the video data streams in each multicast server to a multicast fast-cutting cache server; each multicast server extracts I frame information from the video data stream and synchronizes to the I frame information multicast server in real time; the I-frame information multicast server splices the I-frame information of each multicast channel sent by each multicast server end to form an I-frame information stream; the set top box receives an I-frame information stream from an I-frame information multicast server in real time; when the set top box receives a channel switching request, the time of the next I frame of a multicast channel to be added is analyzed from the I frame information stream, multicast is directly requested to be added to a multicast server when the time of the next I frame is judged to be smaller than or equal to a threshold value, unicast data stream is requested to the multicast fast-cutting cache server when the time of the next I frame is judged to be larger than the threshold value, and then multicast addition is applied to the multicast server.
The method and the system for fast channel switching introduce the I-frame information multicast server, modify the IPTV set top box player and establish the communication mechanism of the I-frame information between the multicast server and the set top box, so that the set top box player can know the arrival time of the next I-frame of all multicast channels in real time. And after receiving the channel switching instruction, the set top box selects to use the FCC server or directly join in the multicast according to the relation between the time of the next I frame from the current distance and the threshold value.
The method and the system can reduce the time delay of switching the multicast channels, ensure the smoothness of playing, and improve the viewing experience of multicast users; on the other hand, the concurrent request quantity of the FCC server can be reduced, so that the cost investment in the aspect of the resources of the FCC server of the supplier is saved, and the functions of reducing the cost and enhancing the efficiency are achieved.
These and other features and advantages will become apparent upon reading the following detailed description and upon reference to the associated drawings. It is to be understood that both the foregoing general description and the following detailed description are explanatory only and are not restrictive of aspects as claimed.
Drawings
The invention will be described in more detail hereinafter with reference to specific embodiments shown in the drawings.
Fig. 1 is a schematic diagram of a prior art fast channel switching system;
FIG. 2 is a schematic diagram of a fast channel switching system of the present invention;
fig. 3 shows a schematic structure of an IP datagram of an I-frame information data stream in the fast channel switching of the present invention.
Fig. 4 is a flow chart of the fast channel switching method of the present invention.
The flowcharts and block diagrams in the figures illustrate the architecture, functionality, and operation of possible implementations of systems, methods according to embodiments of the present application. In this regard, each block in the flowchart or block diagrams may represent a module, segment, or portion of code, which comprises one or more executable instructions for implementing the specified logical function(s).
Detailed Description
The application will be described in more detail hereinafter with reference to specific embodiments shown in the drawings. Various advantages and benefits of this application will become apparent to those of ordinary skill in the art upon reading the following detailed description of the specific embodiments. It should be understood, however, that the present application may be embodied in various forms and should not be limited to the embodiments set forth herein. The following embodiments are provided to enable a more thorough understanding of the present application. Unless otherwise defined, technical or scientific terms used herein should be given the ordinary meaning as understood by one of ordinary skill in the art to which this application belongs.
Fig. 2 is a schematic diagram of a fast channel switching system of the present invention. The system comprises an I-frame information multicast server, a group of 1-N multicast servers, a multicast fast-cutting cache FCC server and an IPTV set top box, wherein the IPTV set top box comprises a player module and a browser. As can be clearly seen by comparing with fig. 1, the invention adds an I-frame information multicast server, and the player module in the set-top box is improved.
The I-frame information multicast server is respectively connected with the multicast server and the IPTV set top box in a communication way and is used for receiving the I-frame information data stream from the multicast server in real time and forwarding the I-frame information data stream to the set top box. Wherein the I-frame information multicast server uses UDP protocol to carry I-frame information data.
According to one embodiment, the set top box has 256 existing multicast channels, and assuming that each multicast server is responsible for video stream push of 2 multicast channels, there are 128 multicast servers, i.e., n=128 as described above. Each multicast server extracts I frame information data from the video stream data, wherein the I frame information data of each multicast channel comprises a start mark, a multicast channel number (which indicates the multicast channel), the arrival time of the next I frame of the multicast channel, the sequence number of the next I frame of the multicast channel and an end mark. The following table shows:
| Field name | Data type | Field length |
| Start sign | String | 1 |
| Channel number (1-N) | Int | 16 |
| Next I-frame arrival time | Timestamp | 32 |
| Next I-frame arrival time sequence number | Int | 16 |
| Termination mark | String | 1 |
The 128-station multicast server pushes 256I-frame information data to the I-frame information multicast server in real time through a transmission interface respectively. The I-frame information multicast server splices the 256I-frame information data of each multicast channel, so that the I-frame information data of each multicast channel are connected end to form UDP user datagram containing the I-frame information data of 256 multicast channels, namely IP datagram.
Fig. 3 shows a schematic structure of an IP datagram. It consists of an IP header and a UDP user datagram, wherein the UDP user datagram includes a UDP header and I-frame information data. The I-frame information data part is: a start flag, a channel number of the 1 st multicast channel, an arrival time of a next I frame of the 1 st multicast channel, a sequence number of a next I frame of the 1 st multicast channel, a start flag … … of a termination flag, a channel number of the 256 th multicast channel, an arrival time of a next I frame of the 256 th multicast channel, a sequence number of a next I frame of the 256 th multicast channel, and a termination flag.
A player module in the set-top box continuously receives and decodes a UDP data stream containing 256 multicast channel I-frame information data from the I-frame information multicast server. When the set top box receives a channel switching request, according to the time of the next I frame of the multicast channel to be added in the UDP data stream received from the I frame information multicast server, judging the time from the next I frame, and if the time is less than or equal to a threshold value, directly requesting the multicast server to add the multicast; if the time is greater than the threshold, a video stream is requested from the multicast fast cut cache FCC server.
Fig. 4 is a flow chart of the fast channel switching method of the present invention.
The video data streams in the multicast server are synchronized and buffered in real time to the multicast fast cut buffer FCC server at step S410.
In step S420, the multicast server extracts I-frame information data from the video stream data and synchronizes to the I-frame information multicast server in real time.
Here, S410 and S420 are performed concurrently, without a sequential order.
In step S430, the I-frame information data of each multicast channel sent by each multicast server is spliced end to end in the I-frame information multicast server to form an I-frame information stream.
In step S440, the set-top box receives the I-frame information stream from the I-frame information multicast server in real time.
When the set-top box receives the channel switch request in step S450, it determines the time to the next I frame according to the information parsed from the I frame information stream in step S460.
If the time interval is greater than the given threshold, proceeding to step 470, the set top box first requests unicast data streams from the multicast fast-cutting cache FCC server, and proceeding to step 480 applies for joining the multicast to the multicast server.
If the time interval is less than or equal to the given threshold, proceeding to step 480, the set-top box directly requests to join the multicast to the multicast server.
It can be seen that the request is sent to the FCC server only when the time is greater than the threshold, thereby achieving the purpose of reducing the number of concurrent requests from the FCC server.
The invention establishes a communication mechanism of I frame information between the multicast server and the set top box by introducing the I frame information multicast server and modifying the IPTV set top box player, so that the set top box player can know the arrival time of the next I frame of all multicast channels in real time, and after the set top box receives a channel switching instruction, the set top box can select to use the FCC server or directly join in multicast according to the relationship between the time of the next I frame and a threshold value.
Compared with the current fast channel switching method for requesting unicast streams from the FCC server by default, the method can accelerate channel switching, improve picture quality, improve user multicast viewing experience, and effectively reduce concurrency pressure of the FCC server, so that excessive FCC servers are not needed, and cost is reduced.
The above embodiments are only for illustrating the technical solution of the present application, and not for limiting the same; although the application has been described in detail with reference to the foregoing embodiments, it will be understood by those of ordinary skill in the art that: the technical scheme described in the foregoing embodiments can be modified or some or all of the technical features thereof can be replaced by equivalents; such modifications and substitutions do not depart from the spirit of the application, and are intended to be included within the scope of the appended claims and description.
Claims (10)
1. A system for fast channel switching comprising:
a plurality of multicast servers;
a multicast fast-cutting cache server communicatively connected with the plurality of multicast servers for synchronizing and caching video data streams in the plurality of multicast servers in real time;
A set top box communicatively connected to the plurality of multicast servers and the multicast fast-cutting cache server, respectively;
Characterized in that the system further comprises:
an I-frame information multicast server which is respectively connected with the multicast servers and the set top box in a communication way and is used for receiving I-frame information extracted from video stream data by the multicast servers in real time from the multicast servers, splicing the I-frame information into an I-frame information stream from head to tail and forwarding the I-frame information stream to the set top box in real time,
The set top box comprises a player module, the player module receives the I-frame information stream from the I-frame information multicast server in real time, when the set top box receives a channel switching request, the time of the next I-frame of a multicast channel to be added is analyzed from the I-frame information stream, and according to the relation between the time of the next I-frame and a threshold value, whether the multicast server is directly requested to be added or the multicast fast-cutting cache server is firstly requested to be unicast data stream, and then the multicast server is requested to be added.
2. The system of claim 1, wherein the I-frame information includes a start flag, a multicast channel number, a time of arrival of a next I-frame for the multicast channel, a sequence number of the next I-frame for the multicast channel, and an end flag.
3. The system of claim 2, wherein the I-frame information multicast server uses a UDP protocol to carry I-frame information to form an I-frame information stream.
4. A system according to claim 3, wherein the I-frame information stream is composed of an IP header and a UDP user datagram, wherein the UDP user datagram includes a UDP header and I-frame information data formed by concatenating I-frame information of each of the multicast servers end to end.
5. The system of claim 1 wherein joining multicast is requested directly from the multicast server when the time to the next I frame is determined to be less than or equal to a threshold and wherein joining multicast is requested from the multicast fast-cutting cache server before the multicast server is requested when the time to the next I frame is determined to be greater than the threshold.
6. A method for fast channel switching in IPTV, comprising:
synchronizing video data streams in each multicast server in real time and caching the video data streams in each multicast server to a multicast fast-cutting cache server;
Each multicast server extracts I frame information from the video data stream and synchronizes the I frame information to the I frame information multicast server in real time;
The I frame information multicast server splices the I frame information of each multicast channel sent by each multicast server end to form an I frame information stream;
The set top box receives the I frame information stream from the I frame information multicast server in real time;
when the set top box receives a channel switching request, analyzing the time of the next I frame of the multicast channel to be added from the I frame information stream, and determining whether to directly request to add multicast to the multicast server or request to unicast data stream to the multicast fast-cutting cache server first and then apply to add multicast to the multicast server according to the relation between the time of the next I frame and a threshold value.
7. The method of claim 6, wherein joining multicast is requested directly from the multicast server when the time from the next I frame is determined to be less than or equal to a threshold, and wherein joining multicast is requested from the multicast fast-cutting cache server before the multicast server when the time from the next I frame is determined to be greater than the threshold.
8. The method of claim 6, wherein the I-frame information includes a start flag, a multicast channel number, a time of arrival of a next I-frame for the multicast channel, a sequence number of the next I-frame for the multicast channel, and an end flag.
9. The method of claim 6, wherein the I-frame information multicast server uses a UDP protocol to carry I-frame information to form an I-frame information stream.
10. The method of claim 9, wherein the I-frame information stream is comprised of an IP header and a UDP user datagram, wherein the UDP user datagram includes a UDP header and I-frame information data formed by concatenating I-frame information of each of the multicast servers end to end.
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Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101656869A (en) * | 2008-08-21 | 2010-02-24 | 华为技术有限公司 | Method, device and system for switching channels |
| CN101753973A (en) * | 2008-12-12 | 2010-06-23 | 华为技术有限公司 | Channel switching method, device and system |
| CN111093090A (en) * | 2018-10-24 | 2020-05-01 | 玲珑视界科技（北京）有限公司 | TCP-based multicast channel fast switching system and method |
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Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101656869A (en) * | 2008-08-21 | 2010-02-24 | 华为技术有限公司 | Method, device and system for switching channels |
| CN101753973A (en) * | 2008-12-12 | 2010-06-23 | 华为技术有限公司 | Channel switching method, device and system |
| CN111093090A (en) * | 2018-10-24 | 2020-05-01 | 玲珑视界科技（北京）有限公司 | TCP-based multicast channel fast switching system and method |
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