A method and system for secure video on demand across physically isolated networks

Abstract

The present invention discloses a method and system for secure video on-demand across physically isolated networks, and relates to the field of cross-network information transmission. The method comprises: selecting a video source number to be on-demand in a second network and decoding to generate a video stream carrying on-demand number data; transmitting the on-demand number video stream to a first network via a video line; determining a corresponding on-demand video stream in the first network according to the received on-demand number video stream; transmitting the on-demand video stream to a second network via a video line; encoding and decoding the on-demand video stream in the second network and outputting it to a display device. The system comprises a first encoder, a first decoder, and an image recognition server deployed in the first network, and a second encoder, a second decoder, and a video on-demand terminal deployed in the second network. The present invention performs on-demand video on-demand across networks only through video lines, avoiding network interconnection, meeting high security and confidentiality requirements across networks, and realizing automation, real-time and high efficiency of the on-demand process.

Description

Technical Field

[0001] The present invention relates to the field of cross-network information transmission, and in particular to a method and system for secure video on demand across physically isolated networks. Background Art

[0002] With the widespread application of video communication systems in emergency command, public security prevention and control, smart transportation and other fields, at the same time, the video resources built by various departments and systems are constantly increasing. In order to meet the needs of controlled sharing and flexible calling of video resources, cross-network on-demand technology of video resources came into being.

[0003] There are two main methods for one-way cross-network video transmission between two networks. One is ground codec, and the other is isolation gateway.

[0004] Among them, the process of on-site encoding and decoding is as follows: the video source in the first network is decoded by the decoder in this network to generate an original video stream, and the video stream is transmitted to the second network through a video cable (HDMI or DVI, etc.), and the encoder in the second network re-encodes it to make it conform to the video encoding specification in the second network, and then decodes the original video stream through the decoder and outputs it to the display device to achieve one-way secure cross-network transmission of the video. This method requires the operation and maintenance personnel of the two networks to communicate offline to confirm the video source, with a low degree of automation, and poor real-time performance and user experience.

[0005] The implementation method of the isolation network gate is: establish an isolation exchange area between the first network and the second network, analyze and audit the video data and control signaling data in the isolation exchange area, and only the video data that passes the security audit can be exchanged across the network. This method can realize real-time video on demand with a high degree of automation, but because the two networks are physically connected, its security is highly dependent on the effectiveness of the security audit function, and there is also a risk of network attacks causing the isolation exchange to fail.

[0006] In some scenarios that require high security and confidentiality, the two networks are physically isolated, and secure and controlled video on demand cannot be performed through firewalls, one-way network gates, etc. Therefore, the existing video security on demand mainly relies on operation and maintenance personnel to customize on-demand needs through phone calls. This method is non-automated, has poor real-time performance, and provides low user experience. Summary of the invention

[0007] The purpose of the present invention is to provide a method and system for secure on-demand video across physically isolated networks, which can realize automated secure on-demand video across physically isolated networks while ensuring real-time performance.

[0008] To achieve the above object, the present invention provides a method for secure video on-demand across physically isolated networks, which is applied to a second network to cross-network video on-demand from a video source in a first network that is physically isolated from the second network. The method for secure video on-demand across physically isolated networks includes:

[0009] The first network and the second network have the same video source number list. In the second network, the video source number to be played on demand in the first network is selected through the video on demand terminal according to the use needs, and the second decoder decodes and generates a video stream carrying the video on demand number data;

[0010] Transmitting the video stream of the on-demand number of the second network to the first network via the video line;

[0011] In the first network, the first encoder encodes the received video stream with the on-demand number, performs image recognition to obtain the video source number to be on-demand, and the first decoder decodes the corresponding video source to be on-demand into the on-demand video stream according to the video source number;

[0012] transmitting the on-demand video stream of the first network to the second network via the video line;

[0013] In the second network, the second encoder encodes the on-demand video stream to become a video source in the second network, and the video decoder decodes the video source and outputs it to the display device, completing cross-network video on demand.

[0014] Optionally, the first network and the second network have the same video source number list. In the second network, the video source number to be played on demand in the first network is selected through the video on demand terminal according to usage needs, and the second decoder decodes and generates a video stream carrying the video on demand number data, which specifically includes:

[0015] The second network periodically and non-real-timely synchronizes the video resource list in the first network, so that the first network and the second network have the same video source number list, as a prerequisite for realizing cross-network video on demand security;

[0016] In the second network, based on the video resource list, the video source number in the first network to be played is selected through the video on demand terminal according to the use needs, and is saved in the second network in the form of an internal video source;

[0017] The second decoder in the second network decodes the video source carrying the numbering data to generate a video stream corresponding to the on-demand number.

[0018] Optionally, transmitting the video stream with a video number on the second network to the first network via a video line specifically includes: a second decoder in the second network sends the video stream with a video number on the second network to a first encoder in the first network via a video line.

[0019] Optionally, in the first network, after encoding the received video stream with the on-demand number, the first encoder performs image recognition to obtain the video source number to be on-demand, and the first decoder decodes the corresponding video source to be on-demand into the on-demand video stream according to the video source number, specifically including:

[0020] In the first network, the first encoder encodes the received video-on-demand numbered video stream to obtain the video-on-demand numbered video, and sends the video to the image recognition server;

[0021] The image recognition server periodically extracts a frame of picture from the on-demand numbered video, and uses a built-in image and video algorithm to recognize the on-demand video source number in the picture;

[0022] The first decoder in the first network determines a video source to be on-demand according to the on-demand video source number, and decodes video data of the video source to be on-demand into a video format to obtain a video stream on-demand.

[0023] Optionally, transmitting the on-demand video stream of the first network to the second network through the video line specifically includes: a first decoder in the first network sends the on-demand video stream to a second encoder in the second network through the video line.

[0024] Optionally, in the second network, a second encoder encodes the on-demand video stream to become a video source in the second network, and a video decoder decodes the video source and outputs it to a display device to complete cross-network video on-demand, specifically including:

[0025] In the second network, the second encoder encodes the received on-demand video stream to comply with a video encoding specification in the second network;

[0026] The on-demand video stream is encoded and transmitted to a video decoder of the display device via the internal network of the second network, and is decoded by the video decoder and sent to the display device for display.

[0027] To achieve the above object, the present invention also provides a video security on-demand system across physically isolated networks, comprising: a first encoder, a second encoder, a first decoder, a second decoder, an image recognition server and a video on-demand terminal;

[0028] The first encoder, the first decoder and the image recognition server are located in a first network; the first network also includes an internal network and a plurality of video sources;

[0029] The second encoder, the second decoder and the video-on-demand terminal are located in a second network; the second network also includes an internal network, a video decoder and a display device;

[0030] There are only two video lines connecting the first network and the second network, namely, between the first encoder and the second decoder, and between the second encoder and the first decoder.

[0031] Optionally, in the second network, the video on demand terminal is used to determine the video on demand source number according to the known video resource list and usage requirements in the first network, generate a video on demand numbered video stream according to the video on demand source number, and encode the video on demand numbered video stream and transmit it to the second decoder via the internal network;

[0032] The second decoder is used to decode the video-on-demand numbered video stream and send it to the first encoder located in the first network through the video line;

[0033] The second encoder is used to receive the on-demand video stream sent by the first decoder in the first network through the video line, encode it and send it to the video decoder associated with the display device in the second network via the internal network, and finally the display device displays the on-demand video.

[0034] Optionally, in the first network, the first encoder is used to receive, through a video line, a video stream with a video number on demand sent by a second decoder in the second network, and encode and send the stream to the image recognition server;

[0035] The image recognition server is used to periodically extract a frame of picture from the received on-demand numbered video, and use the built-in image and video algorithm to identify the on-demand video source number in the picture, and send it to the first decoder;

[0036] The first decoder is used to receive a video-on-demand source corresponding to the video-on-demand source number, decode the video data of the video-on-demand source into a video format, and send it to a second encoder located in the second network through a video line.

[0037] According to the specific embodiments provided by the present invention, the present invention discloses the following technical effects: the present invention converts the on-demand video source number into a video stream, which is sent from the second network to the first network through a video line, and then the on-demand video source number in the video stream is identified, the video stream of the corresponding on-demand video source is determined, and it is sent to the second network for display through the video line, and video is played on demand across networks only through the video line, thereby realizing a one-way cross-network secure on-demand function that is securely controlled and automated without network connection, which not only meets the high security and confidentiality requirements across networks and domains, but also realizes the automation, real-time and high efficiency of the on-demand process, thereby ensuring the user experience. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0039] Figure 1 The present invention provides a flow chart of a method for secure video on-demand across physically isolated networks.

[0040] Figure 2 A schematic diagram of a secure video-on-demand system across physically isolated networks provided by the present invention.

[0041] Figure 3 Another schematic diagram of the secure video-on-demand system across physically isolated networks provided by the present invention. DETAILED DESCRIPTION

[0042] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0043] The purpose of the present invention is to provide a method and system for secure video on-demand across physically isolated networks, which transmits video signals only through video lines, thereby meeting high security and confidentiality requirements across networks and domains, while achieving automation, real-time and high efficiency of the on-demand process, and ensuring the user experience.

[0044] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0045] like Figure 1 As shown, the method for secure video on demand across physically isolated networks provided by the present invention includes:

[0046] Step 1: The first network and the second network have the same video source number list. In the second network, the video source number in the first network to be on demand is selected through the video on demand terminal according to usage needs, and the second decoder decodes and generates a video stream carrying the on-demand number data.

[0047] Specifically, (1) the second network periodically and non-real-time synchronizes the video resource list in the first network, so that the first network and the second network have the same video source number list, as a prerequisite for achieving cross-network video security on-demand. The present invention synchronizes information in an out-of-band manner and does not involve cross-network information interaction.

[0048] (2) In the second network, based on the video resource list, the video source number in the first network to be played is selected through the video on demand terminal according to usage needs, and is stored in the second network in the form of an internal video source.

[0049] (3) The second decoder in the second network decodes the video source carrying the number data to generate a video stream corresponding to the on-demand number.

[0050] In this embodiment, the user in the second network determines the video source number to be projected on demand to the display device according to actual needs and the video resource list, and generates a video data packet containing the video source number. The second decoder in the second network decodes the video data packet into a video stream with a video number on demand.

[0051] As another implementation, the video on demand terminal in the second network directly generates a video stream carrying number data, that is, obtains a video stream with a number on demand. That is, the second decoder may not be deployed in the second network, and the video on demand terminal is directly connected to the first encoder in the first network through a video line.

[0052] Step 2: Transmit the on-demand numbered video stream of the second network to the first network via a video line.

[0053] Specifically, the second decoder in the second network sends the on-demand numbered video stream to the first encoder in the first network via a video line, which may be an HDMI line or a DVI line.

[0054] Step 3: In the first network, the first encoder encodes the received video stream with the on-demand number, performs image recognition to obtain the video source number to be on-demand, and the first decoder decodes the corresponding video source to be on-demand into the on-demand video stream according to the video source number.

[0055] Specifically, (1) in the first network, the first encoder encodes the received video stream with a VOD number to obtain a VOD number video, and sends it to the image recognition server. In this embodiment, the first encoder encodes the received video stream with a VOD number and then encapsulates it into an IP format.

[0056] (2) The image recognition server periodically extracts a frame of picture from the on-demand numbered video and uses a built-in image and video algorithm to identify the on-demand video source number in the picture.

[0057] (3) The first decoder in the first network determines the video source to be on-demand according to the on-demand video source number, and decodes the video data of the video source to be on-demand into a video format to obtain a on-demand video stream.

[0058] The first encoder in the first network is connected to the second decoder in the second network via a video line. The first decoder in the first network is connected to the second encoder in the second network via a video line.

[0059] Step 4: Transmit the on-demand video stream of the first network to the second network via the video line.

[0060] Specifically, the first decoder in the first network sends the on-demand video stream to the second encoder in the second network via a video cable, which may be an HDMI cable or a DVI cable.

[0061] Step 5: In the second network, the second encoder encodes the on-demand video stream to become a video source in the second network, and the video decoder decodes the video source and outputs it to the display device, completing the cross-network video on-demand.

[0062] In this embodiment, the second encoder encodes the on-demand video stream and encapsulates it into IP format. It is then transmitted to the video decoder, which decodes the IP format video source into a video signal and sends it to the display device for display, thereby finally realizing real-time video on demand across networks. The display device may be a display screen or a host, etc. The video decoder and the display device may be connected using an HDMI cable, an SDI cable, or a VGA cable.

[0063] In the present invention, when the second network needs to cross-network on-demand video signals of any one of the multiple video sources in the first network that is physically isolated from the second network, a video data packet with a video source number to be on-demand is generated by a video on-demand terminal, transmitted to the second decoder through an internal network, decoded into a video stream with an on-demand number, and then transmitted to the first encoder across the network through a video line, the image recognition server extracts the required on-demand video source number and sends it to the first decoder, the first decoder receives and parses the corresponding video source in the first network, transmits it to the second encoder across the network through a video line, and finally decodes it by the video decoder and sends it to a display device, thereby realizing real-time video on-demand across the network.

[0064] The video signal is transmitted between the first network and the second network only through two video lines, and there is no network connection, which ensures safe cross-network on-demand viewing. Compared with the traditional solution that requires operation and maintenance personnel of the two networks to make on-demand video by phone calls, it not only meets the high security and confidentiality requirements across networks and domains, but also realizes the automation, real-time and high efficiency of the on-demand process, ensuring the user experience.

[0065] Since the first network and the second network are connected only by a video cable (such as an HDMI cable or a DVI cable, etc.) that can transmit video signals, and the amount of video data generated by the camera, graphics card, etc. is too large to be directly transmitted through the network, it is necessary to perform codec conversion through protocols such as H.264. Therefore, the present invention requires conversion between digital format and video format during data transmission, that is, the encoding and decoding process involved in the present invention.

[0066] In addition, if Figure 2 As shown, the present invention also provides a video security on-demand system across physically isolated networks, including: a first encoder, a second encoder, a first decoder, a second decoder, an image recognition server and a video on-demand terminal.

[0067] The first encoder, the first decoder and the image recognition server are located in the first network. The first network also includes an internal network and multiple video sources. The video source is a video signal input terminal, which can be integrated with video surveillance, video conferencing, host and other video sources in actual deployment. The first encoder and the first decoder are connected to the second network through a video cable. The image recognition server is connected to the first encoder and the first decoder respectively. The image recognition server and the first encoder are also connected to the internal network of the first network.

[0068] The second encoder, the second decoder and the video on demand terminal are located in a second network. The second network also includes an internal network, a video decoder and a display device. The video on demand terminal is connected to the second decoder through the second network. The second decoder is connected to the first encoder in the first network through a video line. The second encoder is connected to the video decoder through the second network, and the video decoder is connected to the display device.

[0069] As another embodiment, Figure 3 As shown, the video on demand terminal in the second network directly generates a video stream carrying the video on demand number data, that is, obtains the video on demand number video stream. That is, the second decoder may not be deployed in the second network, and the video on demand terminal is directly connected to the first encoder in the first network through a video line.

[0070] The first network and the second network are connected by only two video lines (such as HDMI lines or DVI lines, etc.), namely, between the first encoder and the second decoder, and between the second encoder and the first decoder.

[0071] The first network and the second network are physically isolated and are only connected through video cables between two pairs of codecs. There are no firewalls, one-way network gates, etc.

[0072] (1) In the second network, the video on demand terminal is used to determine the video on demand source number according to the known video resource list and usage requirements in the first network, generate a video stream with a video on demand number according to the video on demand source number, and encode the video stream with the video on demand number and transmit it to the second decoder via the internal network. Specifically, the video on demand terminal is used to periodically and non-real-time synchronize the video resource list in the first network, receive the video on demand source number selected by the user, and generate a video data packet containing the video on demand source number, and send it to the second decoder via the second network.

[0073] The second decoder is used to decode the video-on-demand numbered video stream and send it to the first encoder located in the first network through a video line.

[0074] The second encoder is used to receive the on-demand video stream sent by the first decoder in the first network through the video line, encode it and send it to the video decoder associated with the display device in the second network via the internal network, and finally the display device displays the on-demand video.

[0075] (2) In the first network, the first encoder is used to receive a video stream with a video number on demand sent by a second decoder in the second network through a video line, encode the stream and send it to the image recognition server.

[0076] The image recognition server is used to periodically extract a frame of picture from the received on-demand numbered video, and use the built-in image video algorithm to identify the on-demand video source number in the picture, and send it to the first decoder. Specifically, the image recognition server is responsible for intercepting the video and identifying the video source number contained in the picture.

[0077] The first decoder is used to receive a video-on-demand source corresponding to the video-on-demand source number, and decode the video data of the video-on-demand source into a video format, and send it to a second encoder in the second network through a video line. Specifically, the first decoder is responsible for decoding a specified video signal and sending it to the second encoder in the second network through a video line.

[0078] In order to better understand the technical solution of the present invention, a specific embodiment is provided below:

[0079] The first network is a video intelligence network that gathers various types of video intelligence. The second network is an internal business network with extremely high security requirements and a confidentiality level no lower than that of the first network. The first network and the second network are physically isolated and there is no network connection.

[0080] The video intelligence content corresponding to the clearly numbered 1 to numbered N in the video resource list (such as video surveillance in a certain place, a certain type of video conference, etc.) is regularly synchronized by the operation and maintenance personnel of the first network and the second network in an out-of-band manner. This video resource list can be a clear mapping list or operation instructions for the operation and maintenance personnel of the second network to refer to when performing video on-demand. In most scenarios, the first network and the second network are uniformly operation and maintenance managed by the same operation and maintenance personnel, and the specific content of each video source has been clearly defined. The second encoder in the second network is responsible for encoding the video stream originally collected by the camera into a video format suitable for network transmission, and the video decoder is responsible for decoding the encoded video file into the original video stream and connecting to a monitor or large screen for presentation.

[0081] Different from the process of "decoding - video stream transmission - encoding" of on-site encoding and decoding, the present invention adopts the method of "on-demand number decoding - transmission - identifying on-demand number - decoding - encoding", converts the on-demand video source number into a video signal, sends it from the second network to the first network, and then the image processing server identifies the on-demand video source number in the video, modifies the video source configuration in the first decoder. The first decoder receives the video data sent by the video source corresponding to the on-demand video source number in the first network and decodes and sends it to the second network. When specifically implemented, the on-demand video source number can be displayed full-screen on a computer monitor and the monitor screen can be collected in real time, and the on-demand video source number can be converted into a video signal by means of computer screen mirroring, which is simple to operate and ensures real-time performance at the same time.

[0082] To identify the protected on-demand video source number in the video stream, the video signal needs to be periodically sampled into an image signal, that is, video frames are extracted at a certain time period T and saved as images, and sent to the image recognition server to identify the on-demand video source number contained in the image. Among them, the time period T can be set according to usage requirements, and it is recommended that 1s < T < 10s. The image recognition server is responsible for identifying the digital information in the image, and its specific form can be a dedicated server or deployed in the form of software or cloud service.

[0083] The present invention only performs video push through a video cable, realizing a one-way cross-network secure on-demand function without network connection, secure and controlled, and automated, which not only improves the user experience, but also decouples the complicated operation process of operation and maintenance personnel.

[0084] The technical features of the above embodiments can be combined arbitrarily. For the sake of brief description, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, it should be considered to be within the scope described in this specification.

[0085] The principles and implementation methods of the present invention are described in this article using specific examples. The description of the above embodiments is only used to help understand the method and core idea of ​​the present invention. At the same time, for those skilled in the art, according to the idea of ​​the present invention, there will be changes in the specific implementation methods and application scope. In summary, the content of this specification should not be understood as limiting the present invention.

Claims

1. A method for secure video on-demand across physically isolated networks, applied to a second network to cross-network video on-demand from a video source in a first network that is physically isolated from the second network, characterized in that: The method for secure video on demand across physically isolated networks includes: The first network and the second network have the same video source number list. In the second network, the video source number in the first network to be played is selected through the video on demand terminal according to the use needs, and the second decoder decodes and generates a video stream carrying the on-demand number data. Specifically, the second network periodically and non-real-time synchronizes the video resource list in the first network, so that the first network and the second network have the same video source number list as a prerequisite for realizing cross-network video security on demand; in the second network, based on the video resource list, the video source number in the first network to be played is selected through the video on demand terminal according to the use needs, and is saved in the second network in the form of an internal video source; the second decoder in the second network decodes the video source carrying the number data to generate a video stream corresponding to the on-demand number; Transmitting the video stream of the on-demand number of the second network to the first network via the video line; In the first network, the first encoder encodes the received video stream with an on-demand number, performs image recognition to obtain the video source number to be on-demand, and the first decoder decodes the corresponding video source to be on-demand to obtain the on-demand video stream according to the video source number, specifically including: in the first network, the first encoder encodes the received video stream with an on-demand number to obtain the on-demand video, and sends it to the image recognition server; wherein the first encoder encodes the received video stream with an on-demand number and then encapsulates it into an IP format; the image recognition server periodically extracts a frame of picture from the video with the on-demand number, and uses the built-in image and video algorithm to identify the on-demand video source number in the picture; the first decoder in the first network determines the video source to be on-demand according to the on-demand video source number, and decodes the video data of the video source to be on-demand into a video format to obtain the on-demand video stream; transmitting the on-demand video stream of the first network to the second network via the video line; In the second network, the second encoder encodes the on-demand video stream to become a video source in the second network, and the video decoder decodes the video source and outputs it to the display device, completing cross-network video on demand.

2. The method for secure on-demand video playback across physically isolated networks according to claim 1, characterized in that: Transmitting the on-demand numbered video stream of the second network to the first network through the video line, specifically including: The second decoder in the second network sends the on-demand numbered video stream to the first encoder in the first network through a video line.

3. The method for secure video on demand across physically isolated networks according to claim 1, characterized in that: Transmitting the on-demand video stream of the first network to the second network through the video line specifically includes: The first decoder in the first network sends the on-demand video stream to the second encoder in the second network through a video line.

4. The method for secure on-demand video playback across physically isolated networks according to claim 1, characterized in that: In the second network, the second encoder encodes the on-demand video stream to become a video source in the second network, and the video decoder decodes the video source and outputs it to the display device to complete the cross-network video on-demand, which specifically includes: In the second network, the second encoder encodes the received on-demand video stream to comply with a video encoding specification in the second network; The on-demand video stream is encoded and transmitted to a video decoder of the display device via the internal network of the second network, and is decoded by the video decoder and sent to the display device for display.

5. A system for secure video on demand across physically isolated networks, applied to the method for secure video on demand across physically isolated networks as claimed in any one of claims 1 to 4, characterized in that: The video security on-demand system across physically isolated networks includes: a first encoder, a second encoder, a first decoder, a second decoder, an image recognition server and a video on-demand terminal; The first encoder, the first decoder and the image recognition server are located in a first network; the first network also includes an internal network and a plurality of video sources; The second encoder, the second decoder and the video-on-demand terminal are located in a second network; the second network also includes an internal network, a video decoder and a display device; There are only two video lines connecting the first network and the second network, namely, between the first encoder and the second decoder, and between the second encoder and the first decoder.

6. The video security on-demand system across physically isolated networks according to claim 5 is characterized in that: In the second network, the video on demand terminal is used to determine the video on demand source number according to the known video resource list and usage requirements in the first network, generate a video on demand numbered video stream according to the video on demand source number, and encode the video on demand numbered video stream and transmit it to the second decoder via the internal network; The second decoder is used to decode the video stream with a video number and send it to the first encoder located in the first network through the video line; The second encoder is used to receive the on-demand video stream sent by the first decoder in the first network through the video line, encode the on-demand video stream, and then send it to the video decoder associated with the display device in the second network through the internal network, and finally the display device displays the on-demand video.

7. The video security on-demand system across physically isolated networks according to claim 5, characterized in that: In the first network, the first encoder is used to receive a video stream with a video number on demand sent by a second decoder in the second network through a video line, and encode and send the stream to an image recognition server; The image recognition server is used to periodically extract a frame of picture from the received on-demand numbered video, and use the built-in image and video algorithm to identify the on-demand video source number in the picture, and send it to the first decoder; The first decoder is used to receive a video-on-demand source corresponding to the video-on-demand source number, decode the video data of the video-on-demand source into a video format, and send it to a second encoder located in the second network through a video line.

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