System and method for an IP video switcher with no limit on the number of video signals

Abstract

The present invention provides a system and method for an IP video switcher that is not limited by the number of video signals, relating to the technical fields of broadcasting and video production. Among them, the switching control panel is used to respond to the user's switching operation and send the generated switching instruction to the switcher control module; the switcher control module is used to parse the switching instruction and send the parsed instruction to the switcher video input module to notify the switcher video input module to change the input signal configuration; the switcher video input module is used to subscribe to a new video source from a preset network switch and notify the switcher video switching module to perform video switching after receiving a new complete frame of video signal; the switcher video switching module is used to output the video signal to the network switch through the switcher video output module after completing the video switching. The present invention can realize the IP video switching function that is not limited by the number of video signal inputs to meet the application requirements for switching more video signal sources.

Description

Technical Field

[0001] The present invention relates to the technical field of broadcasting and video production, and particularly to a system and method for an IP video switcher that is not limited by the number of video signals. Background Art

[0002] Traditional broadcast and media production environments typically rely on dedicated SDI (Serial Digital Interface) infrastructure, which performs well in terms of reliability and signal quality but has limitations in terms of flexibility, scalability, and cost-effectiveness. With the improvement of video resolution (such as 4K and 8K) and the maturity of IP (Internet Protocol) technology, the media industry has begun to seek a more flexible, more economical solution that can utilize existing IT infrastructure. The SMPTE ST 2110 standard suite is a set of standards developed by the Society of Motion Picture and Television Engineers (SMPTE) in the United States, aiming to define a new real-time media transmission framework based on IP networks for the professional broadcast and media industry. The development of this set of standards began in 2016, and its main goal is to address the limitations of traditional SDI-based video and audio signal transmission systems. The introduction of the SMPTE ST 2110 standard marks a major shift in the broadcast television industry from traditional SDI infrastructure to IP-based media transmission. This shift not only improves the efficiency and flexibility of media production but also reduces operating costs and promotes the digital transformation of the media industry.

[0003] Traditional SDI-based video switchers are a core device in the field of professional broadcast and video production, used for real-time switching and mixing between multiple video sources to create complex video programs or live broadcasts. SDI-based video switchers have the following defects: (1) The number of video signal inputs is limited. The number of physical interfaces for video signal inputs is fixed, and one physical interface corresponds to one video signal, which cannot meet the application scenarios with more video signal sources; (2) Scalability is limited. SDI systems usually rely on physical connections, which means that increasing input or output capabilities requires more SDI cables and devices, resulting in increased wiring complexity and cost; (3) Flexibility is relatively low. The transmission distance of SDI signals is limited, generally not exceeding 100 meters, which restricts the flexibility of device layout and cannot meet the use in large venues or long-distance transmission scenarios. Summary of the Invention

[0004] To overcome the deficiencies of the prior art, the objective of the present invention is to provide a system and method for an IP video switcher that is not limited by the number of video signals, realizing an IP video switching function that is not restricted by the number of video signal inputs, so as to meet the application requirements for switching more video signal sources.

[0005] To achieve the above objective, the present invention provides the following solutions:

[0006] A system for an IP video switcher that is not limited by the number of video signals, comprising: a switching control panel, a switcher control module, a switcher video input module, a switcher video switching module, and a switcher video output module;

[0007] The switching control panel is used to respond to the switching operation of a user's video signal and send the generated switching instruction to the switcher control module; the switcher control module is used to parse the switching instruction and send the parsed instruction to the switcher video input module to notify the switcher video input module to change the input signal configuration; the switcher video input module is used to subscribe to a new video source from a preset network switch and notify the switcher video switching module to perform video switching after receiving a new complete video signal frame; the switcher video switching module is used to output the video signal to the network switch through the switcher video output module after completing the video switching.

[0008] A method for an IP video switcher that is not limited by the number of video signals, applied to the above system for an IP video switcher that is not limited by the number of video signals, the method comprising:

[0009] Select a video signal on the switching control panel for switching, and use the switching control panel to send the UDP multicast address and port number of the video signal to the switcher control module through the network TCP protocol;

[0010] After the switcher control module receives the UDP multicast address and port number, determine whether the video signal is on channel A. If so, modify the configuration of channel B to the received UDP multicast address and port number and notify the switcher video input module to change the configuration of channel B. Otherwise, modify the configuration of channel A and notify the switcher video input module to change the configuration of channel A;

[0011] When the switcher video input module receives an instruction to change the configuration of channel A or channel B, subscribe to the video signal of the corresponding UDP multicast address and port number from the network switch;

[0012] When the network switch receives the subscription information, forward the video data packet of the corresponding UDP multicast address and port number to the switcher video input module;

[0013] Determine whether the video input module of the video switcher has received a complete frame of video data. If a complete frame of video data is received, notify the video switching module of the video switcher to perform video signal switching. Otherwise, continue to receive video data packets until a complete frame of video data is received;

[0014] Use the video switching module of the video switcher to switch the video signal. If the video output of the current video output module of the video switcher is configured on channel A, switch the video output of the video output module of the video switcher to channel B. Otherwise, switch the video output to channel A;

[0015] Send the video data of the video output module of the video switcher to the network switch through UDP multicast.

[0016] Preferably, the step of determining whether the video input module of the video switcher has received a complete frame of video data includes:

[0017] Read the video frame timestamp Timestamp from each RTP data packet of a video signal, and read the video format and resolution from the SDP configuration;

[0018] When the Timestamp is different from the Timestamp of the previous RTP data packet, it indicates a new frame of video, and set FrameLength = 0; FrameLength is the total number of bytes of a received frame of video data recorded;

[0019] Continue to receive RTP data packets, and accumulate the length of the video data carried in each RTP data packet, that is, FrameLength = FrameLength + DataLength; DataLength is the number of bytes of the video data carried in the currently received RTP data packet

[0020] Until the Timestamp of the new RTP data packet is different from the previous one, it indicates another new frame of video, and start to determine whether the received video data is complete.

[0021] Preferably, determining whether the received video data is complete includes:

[0022] Calculate whether the received video frame is complete, that is, whether FrameLength is equal to Width * Height * PixelLength. If so, it means that a complete frame of data is received, and the video switching module is notified to perform switching. Otherwise, return to the step "Read the video frame timestamp Timestamp from each RTP packet of the video signal of one path, and read the video format and resolution from the SDP configuration"; where Width and Height respectively represent the width and height of a video frame; PixelLength represents the number of bytes of one pixel.

[0023] Preferably, the value of Width is 3940, and the value of Height is 2180.

[0024] According to the specific embodiments provided by the present invention, the following technical effects are disclosed by the present invention:

[0025] The present invention provides a system and method for an IP video switcher that is not limited to the number of video signals. The system includes: a switching control panel, a switcher control module, a switcher video input module, a switcher video switching module, and a switcher video output module; the switching control panel is used to respond to the switching operation of the user for one path of video signal and send the generated switching instruction to the switcher control module; the switcher control module is used to parse the switching instruction and send the parsed instruction to the switcher video input module to notify the switcher video input module to change the input signal configuration; the switcher video input module is used to subscribe to a new video source from a preset network switch and notify the switcher video switching module to perform video switching after receiving a new complete video signal; the switcher video switching module is used to output the video signal to the network switch through the switcher video output module after completing the video switching. In the present invention, the IP-based video switcher can receive and process any video stream from the network, and theoretically there is no limit to the number of signals. This enables the system to be easily expanded to accommodate more video sources, unlike SDI-based systems that are limited by the number of physical interfaces. Description of the Drawings

[0026] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for use in the embodiments. Obviously, the drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0027] Figure 1 It is a schematic diagram of the system modules provided by the embodiments of the present invention;

[0028] Figure 2 Schematic diagram of system information transmission provided by an embodiment of the present invention;

[0029] Figure 3 Flowchart of the method provided by an embodiment of the present invention;

[0030] Figure 4 Schematic diagram of step flow provided by an embodiment of the present invention.

[0031] Explanation of reference numerals:

[0032] 1. Switch control panel; 2. Switcher control module; 3. Switcher video input module; 4. Switcher video switching module; 5. Switcher video output module; 6. Network switch. Detailed implementation manners

[0033] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0034] To make the above objects, features, and advantages of the present invention more obvious and understandable, the present invention will be further described in detail below with reference to the accompanying drawings and specific implementation manners.

[0035] Figure 1 Schematic diagram of system modules provided by an embodiment of the present invention, as Figure 1 shown, the present invention provides a system of an IP video switcher with unlimited video signal quantities, including: a switch control panel 1, a switcher control module 2, a switcher video input module 3, a switcher video switching module 4, and a switcher video output module 5;

[0036] The switch control panel 1 is used to respond to the switching operation of a user's video signal and send the generated switching instruction to the switcher control module 2; the switcher control module 2 is used to parse the switching instruction and send the parsed instruction to the switcher video input module 3 to notify the switcher video input module 3 to change the input signal configuration; the switcher video input module 3 is used to subscribe to a new video source from a preset network switch 6 and notify the switcher video switching module 4 to perform video switching after receiving a new complete frame of video signal; the switcher video switching module 4 is used to output the video signal to the network switch 6 through the switcher video output module 5 after completing the video switching.

[0037] Specifically, as Figure 2As shown in the figure, in this embodiment, the switching control panel 1 responds to the user's switching operation, sends a switching instruction (control instruction) to the switch control module 2. The switch control module 2 parses the switching instruction, and then uses the control instruction to notify the video input module 3 of the switch to change the input source configuration. After the video input module 3 of the switch completes the configuration, it uses a video switching instruction to notify the video switching module 4 of the switch to perform video switching. After the video switching module 4 of the switch completes the video switching, it outputs the video signal (video stream) through the video output module 5 of the switch.

[0038] As Figure 3 shown, a method for an IP video switch without limiting the number of video signals in this embodiment is applied to the system of an IP video switch without limiting the number of video signals described above. The method includes:

[0039] Step 100: Select a video signal on the switching control panel for switching, and use the switching control panel to send the UDP multicast address and port number of the video signal to the switch control module through the network TCP protocol;

[0040] Step 200: After the switch control module receives the UDP multicast address and port number, determine whether the video signal is on path A. If so, modify the configuration of path B to the received UDP multicast address and port number, and notify the video input module of the switch to perform a configuration change for path B. Otherwise, modify the configuration of path A and notify the video input module of the switch to perform a configuration change for path A;

[0041] Step 300: When the video input module of the switch receives an instruction for a configuration change for path A or path B, subscribe to the video signal of the corresponding UDP multicast address and port number from the network switch;

[0042] Step 400: When the network switch receives the subscription information, forward the video data packet of the corresponding UDP multicast address and port number to the video input module of the switch;

[0043] Step 500: Determine whether the video input module of the switch has received a complete frame of video data. If a complete frame of video data is received, notify the video switching module of the switch to perform video signal switching. Otherwise, continue to receive video data packets until a complete frame of video data is received;

[0044] Step 600: Use the video switching module of the switch to switch the video signal. If the video output of the current video output module of the switch is configured on path A, switch the video output of the video output module of the switch to path B. Otherwise, switch the video output to path A;

[0045] Step 700: Send the video data of the video output module of the switcher to the network switch by means of UDP multicast.

[0046] Specifically, as Figure 4 shown, the technical route process of this embodiment is as follows:

[0047] ① Select a video signal on the switch control panel for switching. The switch control panel sends the UDP multicast address and port number of this video signal to the switcher control module through the network TCP protocol;

[0048] ② After receiving the UDP multicast address and port number, the switcher control module determines that if the current output signal of the switcher is on path A, it modifies the configuration of path B to the received UDP multicast address and port number, and then notifies the video input module of the configuration change of path B. Otherwise, it modifies the configuration of path A and notifies the video input module of the configuration change of path A;

[0049] ③ After receiving the configuration change of path A or path B, the video input module of the switcher subscribes to the video signal of the corresponding UDP multicast address and port number from the switch. After receiving the subscription information, the switch starts to forward the video data packets of the corresponding UDP multicast address and port number to the video input module of the switcher;

[0050] Among them, the video signal refers to the video stream transmitted in the IP network. The video stream refers to a sequence of continuous video frames, which are usually encoded and packetized for transmission over the network. The video frame is one of the basic units that make up a video. In the field of video technology and multimedia, a video frame refers to a single still image in a video sequence. A video is composed of a series of continuous video frames, and these frames are played quickly and continuously to form a dynamic visual effect.

[0051] The video data packet refers to a structured data unit for transmitting real-time media data over the network. Each video frame in the video stream will be packed into thousands of RTP video data packets and then transmitted over the network to the destination.

[0052] The subscription information refers to the information sent by the receiver (usually a host or device) to the switch in the network for receiving data of a specific multicast group in network communication. The multicast subscription information enables the receiver to declare its interest in a specific multicast group and allows network devices to forward multicast data based on these interests.

[0053] The video in a video frame refers to a single still image in a video sequence. A video is composed of a series of continuous video frames, and these frames are played quickly and continuously to form a dynamic visual effect.

[0054] ④The video input module of the switcher determines whether a complete video frame has been received. If a complete video frame data has been received, it notifies the video switching module of the switcher to perform video signal switching. Otherwise, it continues to receive video data packets until a complete video frame data is received;

[0055] ⑤The video switching module of the switcher switches the video signal. If the current video output module is on channel A, it switches the video output to channel B. Otherwise, it switches the video output to channel A;

[0056] ⑥The video output module of the switcher sends the video data to the network via UDP multicast;

[0057] The algorithm for the process ④ to determine whether a complete video frame has been received is specifically as follows:

[0058] I. Read the video frame timestamp Timestamp from each RTP data packet, and read the video format and resolution from the SDP configuration;

[0059] The RTP data packet refers to a network protocol data designed to transmit real-time multimedia data (such as audio and video). Each video frame will be packed into thousands of RTP video data packets and then transmitted over the network to the destination.

[0060] II. When the Timestamp is different from the Timestamp of the previous data packet, it indicates a new video frame, and set FrameLength = 0;

[0061] III. Continue to receive data packets, and accumulate the length of the video data carried in each data packet, that is, FrameLength = FrameLength + DataLength;

[0062] IV. Until the Timestamp of the new data packet is different from the previous one, it indicates another new video frame, and start to calculate whether the received video frame is complete, that is, whether FrameLength is equal to Width * Height * PixelLength;

[0063] V. If FrameLength is equal to Width * Height * PixelLength, it indicates that a complete frame of data has been received, and notify the video switching module to perform switching. Otherwise, return to process I;

[0064] In the process ①, UDP (User Datagram Protocol) multicast is a communication method that allows one or more senders (multicast sources) to send a single data packet to a group of receivers (multicast group) without establishing a separate connection between each receiver. The UDP multicast address is within the range of special IPv4 addresses and is specifically used for multicast communication, ranging from 224.0.0.0 to 239.255.255.255. The multicast port number is used to identify a specific application or service at the receiving end. In an IP video switcher system with an unlimited number of video signals, each video signal is bound to a UDP multicast address and port number. The TCP (Transmission Control Protocol) is a key protocol in the Internet Protocol Suite (commonly known as TCP / IP), mainly used to provide reliable, connection-oriented data transfer services in an unreliable internetwork. TCP is located in the transport layer of the OSI (Open Systems Interconnection) model and works together with IP (Internet Protocol) to form the basis of modern internet data communication.

[0065] In the process ②, Channel A and Channel B are two preset video input signals in an IP video switcher system with an unlimited number of video signals. The video input signal sources of Channel A and Channel B can be dynamically changed, that is, by changing the UDP multicast address and port number of the video input signal sources of Channel A and Channel B.

[0066] In the process I, an RTP (Real-time Transport Protocol) data packet is a network protocol data packet designed to transport real-time multimedia data (such as audio and video). It provides a timestamp, sequence number, and synchronization source identifier for reconstructing data packets and restoring media streams at the receiving end. The timestamp Timestamp is carried in the header of the RTP data packet. The timestamp field is used to identify the sampling moment of the first sample contained in the RTP data packet, which is very crucial information for decoding and presenting media data. The SDP (Session Description Protocol) is a text format used to describe multimedia sessions, mainly used to describe the attributes of the media streams contained in the session, such as the formats of audio and video, coding types, transport protocols, port information, and other related session parameters.

[0067] In the process II, FrameLength is an internal variable of the system, used to record the total number of bytes of a received video frame.

[0068] In Process III, DataLength is an internal system variable used to record the number of bytes of video data carried in the currently received RTP packet. FrameLength = FrameLength + DataLength means adding the number of bytes of video data carried in the currently received RTP packet to the FrameLength variable.

[0069] In Process IV, Width and Height are parameters read from the SDP configuration, representing the width and height of the video. By default, Width = 3940 and Height = 2180. PixelLength is a parameter read from the SDP configuration, representing the number of bytes per pixel, which is 2.5 bytes, that is, 10 bits for each of the Y, U, and V colors (1 byte = 8 bits), and two pixels share one U and V value. Width * Height * PixelLength means calculating the total number of pixels in the video frame by multiplying the video frame width Width by the height Height, and then multiplying by the number of bytes per pixel PixelLength to calculate the total number of bytes for one frame of video.

[0070] The present invention overcomes the limitations of many traditional SDI-based video switchers and provides a series of significant advantages, especially in terms of the number of video signals, scalability, and flexibility. The following are some of the main advantages of the present invention:

[0071] (1) Unlimited number of video signals: The IP-based video switcher can receive and process any video stream from the network, and theoretically there is no limit to the number of signals. This enables the system to easily expand to accommodate more video sources, unlike SDI-based systems that are limited by the number of physical interfaces.

[0072] (2) High scalability: The IP architecture allows new inputs or outputs to be easily added by simply adding the corresponding devices to the network without the need to add additional physical lines. This not only simplifies the wiring but also reduces costs.

[0073] (3) Flexibility and remote access: The IP video switcher is not restricted by physical location and can be remotely accessed and controlled, enabling the device to be deployed at different locations and centrally managed through the network. This is very beneficial for large venues or scenarios that require remote operation.

[0074] The various embodiments in this specification are described in a progressive manner. Each embodiment focuses on the differences from other embodiments, and the same or similar parts among the embodiments can be referred to each other.

[0075] In this article, specific examples are used to elaborate on the principles and implementation modes of the present invention. The description of the above embodiments is only used to help understand the method and its core idea of the present invention; at the same time, for those of ordinary skill in the art, according to the idea of the present invention, there will be changes in the specific implementation modes and application scopes. To sum up, the content of this specification should not be construed as a limitation on the present invention.

Claims

1. A method for an IP video switcher with unlimited number of video signals, characterized in that: A system applied to an IP video switcher with unlimited number of video signals, the system comprising: a switching control panel, a switcher control module, a switcher video input module, a switcher video switching module and a switcher video output module; the switching control panel is used to respond to a user's switching operation of one video signal and send the generated switching instruction to the switcher control module; the switcher control module is used to parse the switching instruction and send the parsed instruction to the switcher video input module to notify the switcher video input module to change the input signal configuration; the switcher video input module is used to subscribe to a new video source from a preset network switch and notify the switcher video switching module to perform video switching after receiving a new complete frame of video signal; the switcher video switching module is used to output the video signal to the network switch through the switcher video output module after completing the video switching; The method comprises: Select one video signal on the switch control panel for switching, and use the switch control panel to send the UDP multicast address and port number of the video signal to the switch control module through the network TCP protocol; After the switch control module receives the UDP multicast address and port number, it determines whether the video signal of one channel is on channel A. If so, it modifies the configuration of channel B to the received UDP multicast address and port number, and notifies the switch video input module to change the configuration of channel B. Otherwise, it modifies the configuration of channel A and notifies the switch video input module to change the configuration of channel A. When the switcher video input module receives the command of A-channel configuration change or B-channel configuration change, it subscribes to the video signal of the corresponding UDP multicast address and port number from the network switch; When the network switch receives the subscription information, it forwards the video data packet with the corresponding UDP multicast address and port number to the switcher video input module; Determine whether the switcher video input module has received a complete frame of video data, if so, notify the switcher video switching module to switch the video signal, otherwise, continue to receive video data packets until a complete frame of video data is received; The video signal is switched by using the video switching module of the switcher. If the video output of the current video output module of the switcher is configured on channel A, the video output of the video output module of the switcher is switched to channel B; otherwise, the video output is switched to channel A. Sending the video data of the switcher video output module to the network switch via UDP multicast; The step of determining whether the switcher video input module has received a complete frame of video data comprises: Read the video frame timestamp from each RTP packet of the video signal of one channel, and read the video format and resolution from the SDP configuration; When the Timestamp is different from the Timestamp of the previous RTP data packet, it indicates a new frame of video, and FrameLength is set to 0; FrameLength is the total number of bytes of the received frame of video data; Continue to receive RTP data packets, and add up the length of the video data carried in each RTP data packet, that is, FrameLength = FrameLength + DataLength; DataLength is the number of bytes of video data carried in the currently received RTP data packet. When the Timestamp of the new RTP data packet is different from the previous one, it indicates another new frame of video, and then we start to judge whether the received video data is complete. Determine whether the received video data is complete, including: Calculate whether the received frame of video is complete, that is, whether FrameLength is equal to Width*Height*PixelLength. If so, it means that a complete frame of data is received, and the video switching module is notified to switch. Otherwise, return to step "read the video frame timestamp Timestamp from each RTP data packet of the video signal of one channel, and read the video format and resolution from the SDP configuration"; where Width and Height represent the width and height of a frame of video respectively; PixelLength represents the number of bytes of a pixel.

2. The method of IP video switching station with unlimited number of video signals according to claim 1, characterized in that: The value of Width is 3940 and the value of Height is 2180.

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