CN112188302A - Data communication system, method and medium for VR system - Google Patents
Data communication system, method and medium for VR system Download PDFInfo
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- CN112188302A CN112188302A CN202011060080.1A CN202011060080A CN112188302A CN 112188302 A CN112188302 A CN 112188302A CN 202011060080 A CN202011060080 A CN 202011060080A CN 112188302 A CN112188302 A CN 112188302A
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- 238000000034 method Methods 0.000 title claims abstract description 17
- 238000004891 communication Methods 0.000 title claims abstract description 15
- 238000012545 processing Methods 0.000 claims description 21
- 238000004590 computer program Methods 0.000 claims description 4
- 230000005540 biological transmission Effects 0.000 abstract description 8
- 230000010076 replication Effects 0.000 abstract description 2
- 230000001360 synchronised effect Effects 0.000 abstract description 2
- 238000005516 engineering process Methods 0.000 description 4
- 238000010586 diagram Methods 0.000 description 3
- 238000004364 calculation method Methods 0.000 description 2
- 238000005259 measurement Methods 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 230000009471 action Effects 0.000 description 1
- 230000002411 adverse Effects 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000002457 bidirectional effect Effects 0.000 description 1
- 230000000903 blocking effect Effects 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 230000003111 delayed effect Effects 0.000 description 1
- 238000011161 development Methods 0.000 description 1
- 238000002474 experimental method Methods 0.000 description 1
- 230000004886 head movement Effects 0.000 description 1
- 230000003993 interaction Effects 0.000 description 1
- 238000009533 lab test Methods 0.000 description 1
- 230000033001 locomotion Effects 0.000 description 1
- 230000002035 prolonged effect Effects 0.000 description 1
- 238000000926 separation method Methods 0.000 description 1
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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]
- H04N21/60—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
- H04N21/647—Control signaling between network components and server or clients; Network processes for video distribution between server and clients, e.g. controlling the quality of the video stream, by dropping packets, protecting content from unauthorised alteration within the network, monitoring of network load, bridging between two different networks, e.g. between IP and wireless
- H04N21/64784—Data processing by the network
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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
- H04N21/41—Structure of client; Structure of client peripherals
- H04N21/426—Internal components of the client ; Characteristics thereof
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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
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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
- H04N21/45—Management operations performed by the client for facilitating the reception of or the interaction with the content or administrating data related to the end-user or to the client device itself, e.g. learning user preferences for recommending movies, resolving scheduling conflicts
- H04N21/462—Content or additional data management, e.g. creating a master electronic program guide from data received from the Internet and a Head-end, controlling the complexity of a video stream by scaling the resolution or bit-rate based on the client capabilities
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- Engineering & Computer Science (AREA)
- Multimedia (AREA)
- Signal Processing (AREA)
- Databases & Information Systems (AREA)
- Computer Networks & Wireless Communication (AREA)
- Computer Security & Cryptography (AREA)
- Two-Way Televisions, Distribution Of Moving Picture Or The Like (AREA)
Abstract
The invention provides a data communication system, a method and a medium applied to a VR system.A video content acquired by multiple devices is the same coded content under the condition of movie playing, at the moment, a downlink data code stream is large and repeated, and the downlink data is distributed in a multicast mode, so that the load of a host or a set top box is reduced; the control flow between the VR equipment and the video host still adopts a unicast mode to transmit data, and the priority setting of a data packet is increased, so that the control flow can be normally received and processed. The invention adopts the data stream multicast mode to carry out downlink data transmission, thereby achieving the purposes of reducing data replication and reducing the load of a host/set top box, so that the common set top box can provide synchronous transmission of multiple VR videos and simultaneously serve a plurality of VR terminal devices.
Description
Technical Field
The present invention relates to, and in particular, to a data communication system, method, and medium applied to a VR system. And more particularly, to the implementation of a data communication architecture for VR systems.
Background
With the great increase in network speed, high-bandwidth low-latency based applications gradually come into the view of users. As a typical application of a large-bandwidth scene, VR (Virtual Reality) technology is also gradually replacing conventional devices such as televisions to become a new video output device for home entertainment. Due to the immersive experience of the VR equipment, each user needs to have independent VR equipment, when the number of access equipment in the same scene is too many, due to the high bandwidth characteristic of VR, the burden of the household video host/video set top box is increased in multiples, so that the phenomena of frame loss, blocking and the like of the user side occur, and the user experience is influenced.
Since VR systems are currently in the early stages of popularity, a common household typically has only one device. In existing VR entertainment systems, the home video host/video set-top box typically provides only one VR data output. According to measurement and calculation, the conventional common host can provide 2-3 paths of high code stream VR audio and video decoding, processing and transmission; and because the common set-top box adopts an embedded chip, the processing capability is weaker than that of a host, and the common set-top box can only provide 1-2 paths of high code stream VR audio/video decoding, processing and transmission. With the rapid development of the VR technology, an audio/video format with a higher code rate appears, and a future family has 3 and 4 VR hosts for common entertainment and interaction, the existing host/set top box cannot bear data output of multiple VR audios/videos by using the original unicast technology, so that the use cost of a user is increased undoubtedly, a stronger host/set top box is required to support the new application scenes, and the popularization of the VR technology is adversely affected;
in the prior art, the data flow/control flow data packets use the same data channel, which may cause the downlink data flow/control flow to overlap, increase the packet loss probability, and increase the delay of the data packets. Under the existing system, repeated measurement and calculation are carried out according to experiments, operation is carried out while high-code-rate VR video playing, the possibility of packet loss or retransmission is increased by about 6% of control flow, and the data packet is delayed by 150ms on average. Due to the phenomenon, the processing delay of the host/set top box is prolonged, the illusion of operation failure is caused to the user, misoperation caused by the user operating again is easily caused, and the user experience is poor.
Patent document CN108271042B (application number: CN201810133524.6) discloses a video data transmission method based on a cable television network, a cloud VR system implementation method, and a cloud VR system, which includes: acquiring VR application picture data in a VR application running environment; converting the video code stream data into a radio frequency signal data stream; decoding the radio frequency signal data stream to obtain current VR picture data and displaying; collecting and transmitting user head motion information and user control information; sending the head movement information of the user and the data stream corresponding to the user control information to a cloud server through a bidirectional cable television network; demodulating the data stream and sending the data stream to a cloud server; and analyzing the operation instruction and generating new VR application picture data.
Disclosure of Invention
In view of the defects in the prior art, an object of the present invention is to provide a data communication system, method and medium for VR system.
As shown in fig. 1, according to the data communication system applied to the VR system provided by the present invention, in the case of playing a movie, video contents acquired by multiple devices are the same encoded content, at this time, a downlink data code stream is large and repeated, and the downlink data is distributed in a multicast manner, so that the load of a host or a set-top box is reduced;
the control flow between the VR equipment and the video host still adopts a unicast mode to transmit data, and the priority setting of a data packet is increased, so that the control flow can be normally received and processed.
Preferably, the method comprises the following steps:
the data processing module and the control flow input and output module;
the data processing module comprises: dividing the video host or set top box side and the VR equipment side;
the control flow input and output module: respectively recording request addresses and the number at a host end, and carrying out priority identification on the data packets; and establishing a kernel layer data priority queue, and preferentially sending a control flow message, wherein the control flow is a unicast data packet.
Preferably, the special address is in ipv4 format, the first segment is fixed as 239(EFH), the last segment is generated by hash coding the URL address requested by the data to generate 24bit data bits, and the 24bit data bits are filled
Preferably, the data processing module:
when a VR device side initiates a data request to a host through a control flow, a control flow module on the video host or a set top box side judges the current video request access number, if the same video request access number is larger than 1, the original downlink data flow repacks the data packet in a network layer in a multicast mode of a special address and sends the data packet out through a network;
and on the VR device side, the data processing module judges whether a request is made for the data stream according to the address, if so, the data stream is received, and if not, the data packet is discarded.
According to the data communication system applied to the VR system, under the condition of movie playing, video contents acquired by multiple devices are the same coded content, at the moment, the downstream data code stream is large and repeated, the downstream data is distributed in a multicast mode, and the load of a host or a set top box is reduced;
the control flow between the VR equipment and the video host still adopts a unicast mode to transmit data, and the priority setting of a data packet is increased, so that the control flow can be normally received and processed.
Preferably, the method comprises the following steps:
a data processing step and a control flow input and output step;
the data processing step comprises: when a VR device side initiates a data request to a host through a control flow, a control flow module on the video host or a set top box side judges the current video request access number, if the same video request access number is larger than 1, the original downlink data flow repacks the data packet in a network layer in a multicast mode of a special address and sends the data packet out through a network; and on the VR device side, the data processing module judges whether a request is made for the data stream according to the address, if so, the data stream is received, and if not, the data packet is discarded.
The control flow input and output step: respectively recording request addresses and the number at a host end, and carrying out priority identification on the data packets; and establishing a kernel layer data priority queue, and preferentially sending a control flow message, wherein the control flow is a unicast data packet.
Preferably, the special address is in ipv4 format, the first segment is fixed as 239(EFH), and the last segment is hash-coded by the URL address of the data request to generate 24-bit data bits and is padded.
According to the present invention, there is provided a computer-readable storage medium storing a computer program, wherein the computer program is executed by a processor to implement the steps of the data communication method applied to the VR system.
Compared with the prior art, the invention has the following beneficial effects:
(1) by adopting a data stream multicast mode to carry out downlink data transmission, the data replication is reduced, the load of a host/set top box is reduced, and an ordinary set top box can provide synchronous transmission of multiple VR videos and simultaneously serve multiple VR terminal devices.
(2) By adopting data stream/control stream separation and improving the priority of the control stream at a data packet network layer, the control stream data packet is preferentially sent/received, so that the time delay of a user for controlling equipment is shortened, the probability of packet loss of the data packet is reduced (according to laboratory test, the packet loss/retransmission probability is close to 0), and the use experience of the user is optimized.
Drawings
Other features, objects and advantages of the invention will become more apparent upon reading of the detailed description of non-limiting embodiments with reference to the following drawings:
FIG. 1 is a block diagram of a system provided by the present invention.
Fig. 2 is a schematic diagram of a flow chart provided by the present invention.
Detailed Description
The present invention will be described in detail with reference to specific examples. The following examples will assist those skilled in the art in further understanding the invention, but are not intended to limit the invention in any way. It should be noted that it would be obvious to those skilled in the art that various changes and modifications can be made without departing from the spirit of the invention. All falling within the scope of the present invention.
The present invention will be described more specifically with reference to examples.
Example (b):
in the multi-user scenario, the patent designs a single/multicast hybrid network transmission architecture. Under the condition of movie and television playing, video contents (movies such as a circular screen and a spherical screen, and 3D surrounding scenes) acquired by multiple devices are the same coded content, and at the moment, the downstream data code stream is large and repeated, so that the downstream data is distributed in a multicast mode (the multicast mode is a mode of performing mass distribution by utilizing the existing Ethernet multicast mode, namely the target address is a multicast address, namely the stream is simultaneously sent to the multiple devices), and the burden of a host/set top box can be greatly reduced; meanwhile, the control flow between the VR equipment and the video host still adopts a unicast mode to transmit data, and the priority setting of a data packet is increased, so that the control flow can be normally received and processed. As shown in fig. 2, is a flow chart diagram.
The technical scheme specifically comprises the following steps: the device comprises a data processing module and a control flow input and output module.
The data processing module is divided into a video host side and a VR device side. When a VR device side initiates a data request to a host through a control flow, a control flow module at a video host/set top box side judges the current video request access number, if the same video request access number is larger than 1, the original downlink data flow repacks the data packet in a network layer in a multicast mode of a special address and sends the data packet out through a network; and on the VR device side, the data processing module judges whether a request is made for the data stream according to the address, if so, the data stream is received, and if not, the data packet is discarded. The first segment of the special address (ipv4 format) is fixed as 239(EFH), and the last segment is generated by hash-coding the URL address requested by the data to generate 24-bit data bits, and is padded.
Under the action of the control flow input and output module, respectively recording request addresses and numbers at the host end, and carrying out priority identification on the data packets; when the module is started, a kernel layer data priority queue is established, and a control flow message is sent preferentially. The control flow is a unicast packet.
In the description of the present application, it is to be understood that the terms "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", and the like indicate orientations or positional relationships based on those shown in the drawings, and are only for convenience in describing the present application and simplifying the description, but do not indicate or imply that the referred device or element must have a specific orientation, be constructed in a specific orientation, and be operated, and thus, should not be construed as limiting the present application.
Those skilled in the art will appreciate that, in addition to implementing the systems, apparatus, and various modules thereof provided by the present invention in purely computer readable program code, the same procedures can be implemented entirely by logically programming method steps such that the systems, apparatus, and various modules thereof are provided in the form of logic gates, switches, application specific integrated circuits, programmable logic controllers, embedded microcontrollers and the like. Therefore, the system, the device and the modules thereof provided by the present invention can be considered as a hardware component, and the modules included in the system, the device and the modules thereof for implementing various programs can also be considered as structures in the hardware component; modules for performing various functions may also be considered to be both software programs for performing the methods and structures within hardware components.
The foregoing description of specific embodiments of the present invention has been presented. It is to be understood that the present invention is not limited to the specific embodiments described above, and that various changes or modifications may be made by one skilled in the art within the scope of the appended claims without departing from the spirit of the invention. The embodiments and features of the embodiments of the present application may be combined with each other arbitrarily without conflict.
Claims (8)
1. A data communication system applied to a VR system is characterized in that under the condition of movie playing, video contents acquired by multiple devices are the same coded content, at the moment, a downlink data code stream is large and repeated, and the downlink data is distributed in a multicast mode, so that the load of a host or a set top box is reduced;
the control flow between the VR equipment and the video host still adopts a unicast mode to transmit data, and the priority setting of a data packet is increased, so that the control flow can be normally received and processed.
2. The data communication system of claim 1, applied to a VR system, comprising:
the data processing module and the control flow input and output module;
the data processing module comprises: dividing the video host or set top box side and the VR equipment side;
the control flow input and output module: respectively recording request addresses and the number at a host end, and carrying out priority identification on the data packets; and establishing a kernel layer data priority queue, and preferentially sending a control flow message, wherein the control flow is a unicast data packet.
3. The data communication system of claim 2, wherein the specific address is in ipv4 format, the first segment is fixed as 239(EFH), and the last segment is generated by hash-coding the URL address requested by the data to generate 24-bit data bits and padded.
4. The data communication system of claim 2, wherein the data processing module is further configured to:
when a VR device side initiates a data request to a host through a control flow, a control flow module on the video host or a set top box side judges the current video request access number, if the same video request access number is larger than 1, the original downlink data flow repacks the data packet in a network layer in a multicast mode of a special address and sends the data packet out through a network;
and on the VR device side, the data processing module judges whether a request is made for the data stream according to the address, if so, the data stream is received, and if not, the data packet is discarded.
5. A data communication method applied to VR system is characterized in that under the condition of video playing, video contents acquired by multiple devices are the same coded content, at the moment, the downstream data code stream is large and repeated, and the downstream data is distributed in a multicast mode, so that the load of a host or a set top box is reduced;
the control flow between the VR equipment and the video host still adopts a unicast mode to transmit data, and the priority setting of a data packet is increased, so that the control flow can be normally received and processed.
6. The method of claim 5, further comprising:
a data processing step and a control flow input and output step;
the data processing step comprises: when a VR device side initiates a data request to a host through a control flow, a control flow module on the video host or a set top box side judges the current video request access number, if the same video request access number is larger than 1, the original downlink data flow repacks the data packet in a network layer in a multicast mode of a special address and sends the data packet out through a network; and on the VR device side, the data processing module judges whether a request is made for the data stream according to the address, if so, the data stream is received, and if not, the data packet is discarded.
The control flow input and output step: respectively recording request addresses and the number at a host end, and carrying out priority identification on the data packets; and establishing a kernel layer data priority queue, and preferentially sending a control flow message, wherein the control flow is a unicast data packet.
7. The method of claim 6, wherein the specific address is in ipv4 format, the first segment is fixed as 239(EFH), and the last segment is generated by hash-coding the URL address requested by the data to generate 24-bit data bits and is padded.
8. A computer-readable storage medium storing a computer program, wherein the computer program, when executed by a processor, implements the steps of the data communication method of any of claims 5 to 7 applied to a VR system.
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| Application Number | Priority Date | Filing Date | Title |
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| CN202011060080.1A CN112188302A (en) | 2020-09-30 | 2020-09-30 | Data communication system, method and medium for VR system |
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| CN202011060080.1A CN112188302A (en) | 2020-09-30 | 2020-09-30 | Data communication system, method and medium for VR system |
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Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20100014519A1 (en) * | 2007-10-15 | 2010-01-21 | Media Patents, S.L. | Methods for managing multicast traffic between sources sending data and hosts requesting data and network equipment used to implement the methods |
| US20180069760A1 (en) * | 2016-09-06 | 2018-03-08 | Smartiply, Inc. | Fog Local Processing and Relaying for Mitigating Latency and Bandwidth Bottlenecks in AR/VR Streaming |
| CN207135230U (en) * | 2017-07-19 | 2018-03-23 | 中国移动通信集团福建有限公司 | A kind of high end STB for supporting the VR helmets |
| CN108307226A (en) * | 2016-09-21 | 2018-07-20 | 中兴通讯股份有限公司 | VR videos based on Web TV or game play system, set-top box |
| US20180350136A1 (en) * | 2017-05-31 | 2018-12-06 | TeMAVR, LLC | Systems and associated methods for creating a viewing experience |
| WO2020166859A1 (en) * | 2019-02-11 | 2020-08-20 | Lg Electronics Inc. | Method and apparatus for transmitting buffer status report by iab node in wireless communication system |
-
2020
- 2020-09-30 CN CN202011060080.1A patent/CN112188302A/en active Pending
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20100014519A1 (en) * | 2007-10-15 | 2010-01-21 | Media Patents, S.L. | Methods for managing multicast traffic between sources sending data and hosts requesting data and network equipment used to implement the methods |
| US20180069760A1 (en) * | 2016-09-06 | 2018-03-08 | Smartiply, Inc. | Fog Local Processing and Relaying for Mitigating Latency and Bandwidth Bottlenecks in AR/VR Streaming |
| CN108307226A (en) * | 2016-09-21 | 2018-07-20 | 中兴通讯股份有限公司 | VR videos based on Web TV or game play system, set-top box |
| US20180350136A1 (en) * | 2017-05-31 | 2018-12-06 | TeMAVR, LLC | Systems and associated methods for creating a viewing experience |
| CN207135230U (en) * | 2017-07-19 | 2018-03-23 | 中国移动通信集团福建有限公司 | A kind of high end STB for supporting the VR helmets |
| WO2020166859A1 (en) * | 2019-02-11 | 2020-08-20 | Lg Electronics Inc. | Method and apparatus for transmitting buffer status report by iab node in wireless communication system |
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Application publication date: 20210105 |