Digital video reception control system and method based on airborne hybrid fiber link

Abstract

This invention discloses a digital video receiving control system and method based on an airborne hybrid fiber optic link, relating to the field of digital video transmission and processing. The system includes multiple fiber optic channel MAC units, a receive scheduling and management unit, a line image framing unit, a receive buffer, a line image logical ID linked list, a receive buffer management unit, an image restoration unit, and a configuration and status register group. The receive scheduling and management unit receives video data frames from the available fiber optic channels; the line image framing unit reassembles the video line data and generates the first line arrival signal; the receive buffer management unit writes the data into the buffer and updates the linked list; the image restoration unit responds to the first line arrival signal and reads the data in the linked list order to restore the image. This invention solves the problem of reliable reception and image restoration of asynchronous video streams from multiple fiber optic channels, and has the advantages of clear structure, flexible configuration, and high reliability.

Description

Technical Field

[0001] This invention relates to the field of digital video transmission and processing, and specifically to a digital video receiving control system and method based on an airborne hybrid fiber optic link. Background Technology

[0002] As avionics systems evolve towards greater integration and modularity, modern airborne platforms are incorporating an increasing number of sensor devices, such as optoelectronic pods, synthetic aperture radar, infrared imagers, and navigation cameras. The high-resolution, high-frame-rate video data generated by these sensors needs to be transmitted in real-time to the cockpit display system or mission processing computer, placing extremely high demands on the bandwidth, real-time performance, and reliability of the airborne video transmission network.

[0003] Fiber Channel (FC) has become the core transmission medium for high-speed video networks in next-generation avionics systems due to its significant advantages, including high bandwidth, low latency, resistance to electromagnetic interference, and support for long-distance transmission. Fiber Channel-based digital video transmission technology can effectively send locally acquired video data to fiber optic links, ensuring timing accuracy and data integrity from the source to the transmission link.

[0004] However, as single-channel video resolution evolves from high definition to 4K / 8K, and the demand for concurrent transmission of multiple video streams increases, relying solely on a single fiber optic channel is no longer sufficient to meet bandwidth requirements. To overcome single-channel bandwidth limitations or achieve redundancy, the transmitting end often uses parallel or cross-transmission of multiple fiber optic channels to transmit video streams. For example, a single high-bandwidth video stream is split into multiple streams for transmission, or multiple video streams are multiplexed and interleaved across multiple channels.

[0005] When these multi-channel video streams, after being split, multiplexed, or framed, arrive at the receiving end, the receiving system faces new technical challenges: how to efficiently and reliably synchronize, buffer, reassemble, and restore images from multiple video data streams from different physical channels that may have asynchronous or non-aligned timing characteristics. Specifically, due to differences in the physical path length of different fiber optic channels and differences in the processing latency of switching equipment, different lines of data from the same image may arrive at the receiving end at different times; the video line data transmitted in frames needs to be accurately stitched together at the receiving end; and data streams from multiple channels need to be intelligently buffered and ordered to ensure that the final restored image lines are in the correct order.

[0006] Existing technologies largely focus on the reception and timing control of single-channel video data, such as traditional point-to-point video transmission and reception schemes. Their processing logic is relatively simple, requiring only the decoding and display of a single data stream. When faced with multi-channel mixed fiber optic link inputs, these schemes lack a coordinated scheduling mechanism, making it impossible to uniformly manage and orderly receive data streams from multiple channels. Simply splicing multiple data streams directly will lead to serious problems such as image frame loss, line data misalignment, and display disorder due to the asynchronous nature of the channels and the frame-segmented transmission characteristics. This will consequently affect the operator's situational awareness and the normal operation of the airborne mission system.

[0007] Therefore, there is an urgent need for a receiver solution that can specifically address the complexity of airborne hybrid fiber optic links. Summary of the Invention

[0008] To address the shortcomings of existing technologies, this invention provides a digital video receiving control system and method based on an airborne hybrid fiber optic link. Through coordinated reception scheduling of multi-channel data, intelligent buffer management, and precise image line data reconstruction, it achieves highly reliable reception of multi-source video streams and complete image recovery.

[0009] To achieve the above objectives, the present invention provides the following technical solution:

[0010] A digital video receiving and control system based on an airborne hybrid fiber optic link includes:

[0011] Multiple Fibre Channel MAC (Media Access Control) units, each with its input terminal corresponding to a fiber optic link, used to receive video data frames from the corresponding fiber optic link;

[0012] The receiving scheduling management unit has its input end connected to the output end of each fiber channel MAC unit, and is used to receive video data frames from each valid fiber channel MAC unit according to a predetermined scheduling strategy.

[0013] The line image framing unit has its input end connected to the output end of the receiving scheduling management unit. It is used to receive video data frames sent by the scheduling management unit, and to parse and reassemble the received video data frames according to the pre-configured framing rules, so as to identify and recover the complete video line data. The line image framing unit is also used to generate a first line arrival signal when the first line of video line data of the current video frame is reassembled, and to send it through the first line arrival output end.

[0014] The receive buffer is used to store the video line data output by the line image framing unit;

[0015] Multiple row image logical ID linked lists, one row image logical ID linked list corresponding to each fiber channel, are used to record the position index of video row data that has been written into the receive buffer in sequence;

[0016] The receive buffer management unit is connected to the output end of the line image framing unit, the write end of the receive buffer, and the update end of the line image logical ID list. It is used to write the video line data output by the line image framing unit into the receive buffer and update the receive buffer status flag and the corresponding line image logical ID list.

[0017] The image restoration unit is connected to the first line arrival output of the line image framing unit, the read end of the line image logical ID linked list, the read end of the receiving buffer, and the write end of the image buffer. In response to the first line arrival signal, according to the video source identifier indicated by the first line arrival signal, the unit reads each video line data sequentially from the receiving buffer according to the order recorded in the line image logical ID linked list of all optical channels corresponding to the video source, and writes the read video line data into the image buffer corresponding to the video source to restore the complete video image.

[0018] The configuration and status register group is connected to the receive scheduling management unit, the line image framing unit, the receive buffer management unit, and the image recovery unit, and is used to store and control the configuration parameters and operating status of each functional unit.

[0019] Furthermore, the configuration and status register group includes:

[0020] The channel validity register, connected to the receive scheduling management unit, is used to enable the specified fiber channel MAC unit;

[0021] A frame configuration register, connected to the row image framing unit, is used to store the frame rules;

[0022] A receive buffer depth register, connected to the receive buffer management unit, is used to configure the depth of the receive buffer;

[0023] A receive buffer valid flag register group is connected to the receive buffer management unit and is used to identify the busy / idle status of each storage location in the receive buffer;

[0024] An image buffer valid flag register, connected to the image recovery unit, is used to identify whether a complete video image has been recovered from the image buffer.

[0025] Furthermore, the receiving buffer management unit is specifically used for:

[0026] Query the valid flag register group of the receive buffer to determine the free storage location in the receive buffer;

[0027] Write the complete video line data to the free location;

[0028] Add the location index of the available location to the corresponding fiber channel's row image logical ID linked list;

[0029] Update the state of the corresponding bit in the receive buffer valid flag register group to indicate that the position is occupied.

[0030] Furthermore, the image restoration unit includes:

[0031] The read control module is connected to the first line arrival output terminal of the line image framing unit and the read terminal of the line image logical ID linked list. It is used to respond to the first line arrival signal and, according to the video source identifier indicated by the first line arrival signal, obtain the position index of the video line data to be read in the order recorded in the line image logical ID linked list of all optical fiber channels corresponding to the video source.

[0032] The image filling module is connected to the read control module, the read end of the receive buffer, and the write end of the image buffer. It is used to read the corresponding video line data from the receive buffer according to the position index obtained by the read control module, and write the read video line data into the corresponding image buffer in the order of the line number.

[0033] The judgment module is connected to the image filling module. It is used to determine whether the entire image has been fully restored based on the video frame size and the number of lines written as defined in the ICD (Interface Control Document). If so, the corresponding position in the image buffer valid flag register is set to valid.

[0034] Furthermore, the predetermined scheduling strategy is either round-robin scheduling or event-driven scheduling.

[0035] Furthermore, the framing rules are determined based on at least one of the video resolution, frame format, and frame frequency parameters defined by the ICD.

[0036] A digital video reception control method based on an airborne hybrid fiber optic link, applied to the above system, includes the following steps:

[0037] S1. Set the fiber channel active status, framing rules, receive buffer depth, and initial status of related flag registers according to the ICD.

[0038] S2. The receiving and scheduling management unit receives video data frames from each valid fiber optic channel MAC unit according to the predetermined scheduling strategy.

[0039] S3. The line image framing unit determines in real time whether the video data frame sequence received from the receiving scheduling management unit is continuous. If it is, it proceeds to S4; otherwise, it discards the current incomplete frame sequence and returns to S2 to wait for new video data frames.

[0040] S4. The line image framing unit parses and reassembles the received video data frames according to the pre-configured framing rules to recover the complete video line data. When reassembling the first line of video line data of the current video frame, it generates the first line arrival signal and sends it to the image recovery unit through the first line arrival output terminal.

[0041] S5. The receiving buffer management unit writes the video line data output by the line image framing unit into the receiving buffer and updates the receiving buffer status flag and the corresponding line image logical ID linked list.

[0042] S6. The image restoration unit responds to the first line arrival signal in real time. According to the video source identifier indicated by the first line arrival signal, it reads each video line data from the receiving buffer in the order of the row image logical ID linked list of all optical fiber channels corresponding to the video source, and writes the read video line data into the image buffer corresponding to the video source to restore the complete video image.

[0043] S7. In real time, determine whether the entire image has been restored. If it has been restored, set the corresponding position of the image buffer valid flag register to valid, and the current video frame processing ends; otherwise, return to S6 to continue reading video line data.

[0044] Furthermore, in S3, the method for determining whether the video data frame sequence is continuous is as follows: by checking the frame count or timestamp information of the video data frame, it is determined whether the currently received video data frame is continuous with the previous video data frame; if the frame count is continuous or the timestamp increases and the interval is less than or equal to a preset threshold, it is determined to be continuous; otherwise, it is determined to be discontinuous.

[0045] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0046] (1) The present invention uses a receiving scheduling management unit to uniformly schedule multiple optical fiber channels, which solves the conflict problem when multiple asynchronous video streams corresponding to a single video source are accessed at the same time; and records the position index of each channel data in sequence through a row image logical ID linked list. Even if the data is out of order due to frame transmission or asynchronous arrival, the image restoration unit can still strictly read the data in the linked list order, ensuring that the restored video image row order is correct, and effectively avoiding image misalignment or disorder.

[0047] (2) The present invention adopts an architecture that combines a shared receiving buffer with an independent row image logical ID linked list. All video row data of all channels are stored in the same receiving buffer, avoiding the waste of resources caused by statically allocating storage space for each channel. At the same time, the continuity of video data frames is judged by the row image framing unit, and incomplete frame sequences are discarded in time, which effectively avoids image splicing errors caused by frame loss and ensures the integrity and reliability of the restored image.

[0048] (3) The present invention implements functional configuration through ICD and configuration and status register group, which can flexibly adapt to video streams with different resolutions, frame formats and frame splitting strategies; each functional unit is modularly designed with clear connection relationship, which is convenient for hardware implementation and system integration, and has good versatility and scalability. Attached Figure Description

[0049] Figure 1 This is a structural block diagram of a digital video receiving and control system based on an airborne hybrid fiber optic link provided in Embodiment 1 of the present invention;

[0050] Figure 2 A flowchart of a digital video receiving control method based on an airborne hybrid fiber optic link provided in Embodiment 2 of the present invention. Detailed Implementation

[0051] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0052] Example 1

[0053] refer to Figure 1 This embodiment provides a digital video receiving and control system based on an airborne hybrid fiber optic link, including multiple fiber channel MAC units (fiber channel MAC unit 1 to fiber channel MAC unit n), a receiving scheduling and management unit, a line image framing unit, a receiving buffer, multiple line image logical ID linked lists (line image logical ID linked list 1 to line image logical ID linked list n), a receiving buffer management unit, an image restoration unit, and a configuration and status register group. The configuration and status register group includes a channel validity register, a framing configuration register, a receiving buffer depth register, a receiving buffer validity flag register group, and an image buffer validity flag register. The configuration and status register group is connected to the configuration input terminals of the receiving scheduling and management unit, the line image framing unit, the receiving buffer management unit, and the image restoration unit, and is used to store and control the configuration parameters and operating status of each functional unit.

[0054] Each Fibre Channel MAC unit has an input corresponding to one fiber optic link; its output is connected to the input of the receiving scheduling management unit.

[0055] The receiving scheduling management unit serves as the core of the system's input scheduling. Its input is also connected to the channel valid register, and its output is connected to the input of the line image framing unit.

[0056] The image framing unit has its input connected to the framing configuration register, its data output connected to the receiving buffer management unit, and its first line arrival output connected to the image restoration unit.

[0057] The receive buffer has its write end connected to the receive buffer management unit and its read end connected to the image restoration unit.

[0058] Multiple row image logical ID linked lists, one row image logical ID linked list corresponding to each fiber channel, the update end of each row image logical ID linked list is connected to the receiving buffer management unit, and the read end of each row image logical ID linked list is connected to the image restoration unit.

[0059] The receive buffer management unit is also connected to the receive buffer depth register and the receive buffer valid flag register group;

[0060] The image restoration unit is also connected to the write end of the image buffer and the image buffer valid flag register;

[0061] Each Fibre Channel MAC unit is used to receive video data frames from the corresponding fiber optic link. In practical implementation, the Fibre Channel MAC unit can be implemented using an IP core based on an FPGA (Field Programmable Gate Array) to perform functions such as 8B / 10B decoding, video data frame parsing, frame delimitation, and CRC (Cyclic Redundancy Check) verification. In this embodiment, the system supports up to 16 fiber optic channels, corresponding to 16 Fibre Channel MAC units. The output of each Fibre Channel MAC unit is connected to the input of the receive scheduling management unit, and it sends the video data frames received from the corresponding fiber optic link to the receive scheduling management unit.

[0062] The receive scheduling management unit determines which Fibre Channel MAC units are valid based on the configuration value of the channel valid register, and receives video data frames from each valid Fibre Channel MAC unit according to a predetermined scheduling strategy. In this embodiment, the predetermined scheduling strategy adopts a polling scheduling method, that is, the receive scheduling management unit maintains a channel pointer internally and polls each valid Fibre Channel MAC unit in turn to check if any video data frames have arrived. The channel valid register is a 16-bit register, with each bit corresponding to a Fibre Channel MAC unit. When the corresponding bit is "1", it indicates that the channel is enabled, and when it is "0", it indicates that the channel is disabled. When the receive scheduling management unit detects that there is a video data frame at the output of a valid Fibre Channel MAC unit, it immediately reads the video data frame and forwards it to the line image framing unit.

[0063] The line image framing unit receives video data frames sent by the scheduling and management unit, and parses and reassembles the received video data frames according to pre-configured framing rules to identify and recover complete video line data. In this embodiment, the framing rules are determined based on parameters such as video resolution, frame format, and frame frequency defined by the ICD. The framing rules define the framing strategy for the video line images received by each fiber channel, guiding the line image framing unit in data reassembly. For example, for a video frame with a resolution of 1920×1080, each line image data may be divided into two video data frames and transmitted to the fiber channel MAC unit. The line image framing unit internally includes a frame parser and a line reassembler. The frame parser identifies which part of which line image each video data frame belongs to according to the framing rules stored in the framing configuration register. The header of each video data frame contains information such as line number and slice number. The line reassembler buffers and splices different video data frames belonging to the same line image to recover complete video line data.

[0064] The line image framing unit is also used to generate a first line arrival signal when the first line of video data of the current video frame is reconstructed, and send it to the image restoration unit through the first line arrival output terminal;

[0065] The receive buffer stores all video line data output by the line image framing unit. In this embodiment, the receive buffer is implemented using dual-port RAM (Random Access Memory), with a capacity to store line data for four complete video frames. The depth of the receive buffer is configured by the receive buffer depth register in the configuration and status register group. For example, for 1080P video with 1080 lines per frame, if the receive buffer depth register is configured to 4320, then line data for four video frames can be stored. Each storage location in the receive buffer corresponds to a unique address index, which is the location index. The receive buffer management unit is responsible for writing all video line data output by the line image framing unit into the storage locations of the receive buffer, and the image restoration unit is responsible for reading video line data from these storage locations.

[0066] The line image logical ID linked list is used to record the position index of the video line data that has been written to the receive buffer in sequence. In this embodiment, the system supports 16 fiber optic channels, so 16 independent line image logical ID linked lists are set up. Each line image logical ID linked list is stored in a dedicated register group or RAM block, and the item in the line image logical ID linked list is the position index of the receive buffer.

[0067] It should be noted that a video source may occupy multiple fiber optic channels for transmission simultaneously. For example, for high-resolution video, the bandwidth of a single fiber optic channel may not be sufficient to carry the complete video data, so the video data needs to be distributed across multiple fiber optic channels for parallel transmission. In this case, the position indices of different video line data from the same video source are distributed in the corresponding line image logical ID linked lists of different fiber optic channels. Each channel's line image logical ID linked list records the position index of the video line data transmitted by that channel in the receive buffer.

[0068] The maintenance of the row image logical ID linked list follows these rules:

[0069] When the receive buffer management unit writes a line of video data into the receive buffer, it adds the location index of the storage location to the end of the corresponding fiber channel's line image logical ID linked list.

[0070] After the image restoration unit reads a line of video data from the receiving buffer, it removes the position index corresponding to the video line data from the head of the line image logical ID linked list (or marks it as read).

[0071] The order of each item in the line image logical ID linked list is the logical order of each video line data transmitted in the corresponding fiber optic channel within that channel. For all fiber optic channels corresponding to a video source, the image restoration unit reads the data sequentially according to the order recorded in the line image logical ID linked list of each fiber optic channel, keeping the line count of the current video frame continuous, thus restoring the complete video frame.

[0072] The receive buffer management unit is used to write the video line data output by the line image framing unit into the receive buffer, and update the receive buffer status flags and the corresponding line image logical ID linked list; the specific workflow of the receive buffer management unit is as follows:

[0073] The receive buffer valid flag register group is queried to determine the free storage location of the receive buffer. The receive buffer valid flag register group is a bitmap structure, with each bit corresponding to a storage location in the receive buffer, where "0" indicates free and "1" indicates occupied.

[0074] Write the complete video line data output by the line image framing unit to a determined free storage location.

[0075] The location index of the available position is added to the corresponding fiber channel's row image logical ID linked list. The correspondence is determined based on the fiber channel to which the currently processed video row data belongs.

[0076] Update the status of the corresponding bit in the receive buffer valid flag register group, and mark the position as "occupied" to indicate that there is valid data at that position.

[0077] The image restoration unit responds in real time to the first line arrival signal. Based on the video source identifier indicated by the first line arrival signal, it sequentially reads each video line data from the receive buffer according to the order recorded in the row image logical ID linked list of all fiber optic channels corresponding to that video source, and writes the read video line data into the image buffer corresponding to that video source, thus restoring the complete video image. The image restoration unit includes three functional modules: a read control module, an image filling module, and a completion judgment module.

[0078] The read control module is connected to the first line arrival output of the line image framing unit and the read end of the line image logical ID linked list. It responds in real-time to the first line arrival signal and, based on the video source identifier indicated by the first line arrival signal, obtains the position index of the video line data to be read according to the order recorded in the line image logical ID linked list of all fiber optic channels corresponding to that video source. Specifically, when the first line arrival signal is received, the read control module parses the video source identifier carried by the signal, locks all fiber optic channels corresponding to that video source, and then sequentially obtains the position index starting from the head of the line image logical ID linked list corresponding to these channels. Each obtained position index is then passed to the image filling module.

[0079] The image filling module is connected to the read control module, the read end of the receive buffer, and the write end of the image buffer. It reads the corresponding video line data from the receive buffer based on the position index obtained by the read control module, and writes the read video line data into the corresponding image buffer in the order of the line numbers of the current video frame. Once the image filling module has written all the line data of a video frame into the corresponding image buffer in sequence, the restoration of a complete video image is complete.

[0080] The completion judgment module is connected to the image filling module and is used to determine whether the entire image has been fully restored based on the video frame size (total number of lines) defined by the ICD and the number of lines already written. When the number of lines already written reaches the total number of video frames, it is determined that the current image restoration is complete, and the corresponding position of the image buffer valid flag register is set to valid, indicating that the image in the image buffer is available for subsequent display or processing units.

[0081] Example 2

[0082] refer to Figure 2 Based on the system provided in Embodiment 1, this embodiment provides a digital video reception control method based on an airborne hybrid fiber optic link, which is executed according to the following steps:

[0083] S1. After the system is powered on or reset, perform initialization configuration according to the ICD, which includes the following sub-steps:

[0084] Configure the enabled status of Fibre Channels: Determine which Fibre Channels are enabled based on the ICD configuration channel enable register;

[0085] Set framing rules: Define the framing method for each row of images according to the ICD framing configuration register;

[0086] Set the receive buffer depth: Determine the buffer size according to the ICD configuration receive buffer depth register;

[0087] Initialize relevant flag registers: Clear all bits of the receive buffer valid flag register group and clear all bits of the image buffer valid flag register.

[0088] S2. The receiving scheduling management unit receives video data frames from each valid fiber optic channel MAC unit according to the predetermined scheduling strategy; each received video data frame is forwarded to the line image framing unit.

[0089] S3. The line image framing unit determines in real time whether the sequence of video data frames received from the receiving scheduling management unit is continuous. The determination method is as follows: by checking the frame count or timestamp information in the video data frames, it is determined whether the currently received video data frame is continuous with the previous video data frame. If the frame count method is used, it checks whether the frame count of the current frame is equal to the frame count of the previous frame plus 1. If so, it is determined to be continuous. If the timestamp method is used, it checks whether the timestamp of the current frame is greater than the timestamp of the previous frame, and the timestamp difference is less than or equal to a preset threshold. If so, it is determined to be continuous.

[0090] If the data is determined to be continuous, proceed to S4; if it is determined to be discontinuous, the line image framing unit notifies the receive buffer management unit to perform a discard operation. The receive buffer management unit clears the buffer validity flag corresponding to the data of the current video frame already written to the receive buffer, and removes the position indices of these positions from the line image logical ID linked list of the corresponding fiber channel. Simultaneously, the line image framing unit records the sequence number of the current video frame; subsequent video data frames belonging to the current video frame will be directly ignored without any parsing, writing, or linked list recording. The receive state of the current video frame is reset, and the process returns to S2, waiting to receive the next video data frame.

[0091] S4. The line image framing unit parses and reassembles the received video data frames according to the pre-configured framing rules to recover the complete video line data. Simultaneously, when reassembling the first line of video data for the current video data frame, it generates a first line arrival signal and sends it to the image restoration unit via the first line arrival output. The specific process of recovering the complete video line data is as follows:

[0092] The frame parser of the line image framing unit parses the header information of each video data frame to obtain its line number and slice number;

[0093] The line reassembler of the line image framing unit splices video data frames with different segment numbers belonging to the same line number in sequence; when all segments of a line of data have been received, the complete video line data is recovered.

[0094] S5. The receive buffer management unit performs the following operations:

[0095] Query the receive buffer valid flag register group, find the first free bit that is "0", and determine the corresponding free storage location;

[0096] Write the complete video line data output by the line image framing unit to this free storage location;

[0097] Add the location index of the free position to the end of the corresponding fiber channel's row image logical ID linked list;

[0098] Update the status of the corresponding bit in the receive buffer valid flag register group and mark the position as "1" (occupied).

[0099] S6. In response to the first line arrival signal, the image restoration unit performs the following operations based on the video source identifier indicated by the first line arrival signal:

[0100] The read control module locks all fiber optic channels corresponding to the video source; starting from the head of the row image logical ID chain list corresponding to these channels, it sequentially obtains the position index of the video row data to be read and sends it to the image filling module;

[0101] The image filling module reads the corresponding video line data from the receiving buffer based on the obtained position index, and writes the read video line data into the image buffer corresponding to the video source in line order.

[0102] S7. The completion judgment module in the image restoration unit determines in real time whether the entire image has been restored based on the video frame size (total number of lines) defined by the ICD and the number of lines written to the image buffer. If the number of lines written reaches the total number of video frames, the current image restoration is determined to be complete, and the corresponding position of the image buffer valid flag register is set to "1", indicating that a complete image of the video source is ready. If the total number of image lines has not been reached, it returns to S6 and continues to read the next line of data.

[0103] The specific embodiments of the present invention are provided to enable those skilled in the art to understand or implement the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention.

[0104] It should be understood that the present invention is not limited to the content already described above, and various modifications and changes can be made without departing from its scope. The scope of the present invention is limited only by the appended claims.

Claims

1. A digital video receiving and control system based on an airborne hybrid fiber optic link, characterized in that, include: Multiple Fibre Channel MAC Units, each with its input terminal corresponding to a fiber optic link, are used to receive video data frames from the corresponding fiber optic link. The receiving scheduling management unit has its input end connected to the output end of each fiber channel MAC unit, and is used to receive video data frames from each valid fiber channel MAC unit according to a predetermined scheduling strategy. The line image framing unit has its input end connected to the output end of the receiving scheduling management unit. It is used to receive video data frames sent by the scheduling management unit, and to parse and reassemble the received video data frames according to the pre-configured framing rules, so as to identify and recover the complete video line data. The line image framing unit is also used to generate a first line arrival signal when reconstructing the first line of video line data of the current video frame, and send it through the first line arrival output terminal; The receive buffer is used to store the video line data output by the line image framing unit; Multiple row image logical ID linked lists, one row image logical ID linked list corresponding to each fiber channel, are used to record the position index of video row data that has been written into the receive buffer in sequence; The receive buffer management unit is connected to the output end of the line image framing unit, the write end of the receive buffer, and the update end of the line image logical ID list. It is used to write the video line data output by the line image framing unit into the receive buffer and update the receive buffer status flag and the corresponding line image logical ID list. The image restoration unit is connected to the first line arrival output of the line image framing unit, the read end of the line image logical ID linked list, the read end of the receiving buffer, and the write end of the image buffer. In response to the first line arrival signal, according to the video source identifier indicated by the first line arrival signal, the unit reads each video line data sequentially from the receiving buffer according to the order recorded in the line image logical ID linked list of all optical channels corresponding to the video source, and writes the read video line data into the image buffer corresponding to the video source to restore the complete video image. The configuration and status register group is connected to the receive scheduling management unit, the line image framing unit, the receive buffer management unit, and the image recovery unit, and is used to store and control the configuration parameters and operating status of each functional unit.

2. The digital video receiving and control system based on an airborne hybrid fiber optic link according to claim 1, characterized in that, The configuration and status register group includes: The channel validity register, connected to the receive scheduling management unit, is used to enable the specified fiber channel MAC unit; A frame configuration register, connected to the row image framing unit, is used to store the frame rules; A receive buffer depth register, connected to the receive buffer management unit, is used to configure the depth of the receive buffer; A receive buffer valid flag register group is connected to the receive buffer management unit and is used to identify the busy / idle status of each storage location in the receive buffer; An image buffer valid flag register, connected to the image recovery unit, is used to identify whether a complete video image has been recovered from the image buffer.

3. The digital video receiving and control system based on an airborne hybrid fiber optic link according to claim 2, characterized in that, The receive buffer management unit is specifically used for: Query the valid flag register group of the receive buffer to determine the free storage location in the receive buffer; Write the complete video line data to the free location; Add the location index of the available location to the corresponding fiber channel's row image logical ID linked list; Update the state of the corresponding bit in the receive buffer valid flag register group to indicate that the position is occupied.

4. The digital video receiving and control system based on an airborne hybrid fiber optic link according to claim 2, characterized in that, The image restoration unit includes: The read control module is connected to the first line arrival output terminal of the line image framing unit and the read terminal of the line image logical ID linked list. It is used to respond to the first line arrival signal and, according to the video source identifier indicated by the first line arrival signal, obtain the position index of the video line data to be read in the order recorded in the line image logical ID linked list of all optical fiber channels corresponding to the video source. The image filling module is connected to the read control module, the read end of the receive buffer, and the write end of the image buffer. It is used to read the corresponding video line data from the receive buffer according to the position index obtained by the read control module, and write the read video line data into the corresponding image buffer in the order of the line number. The completion judgment module is connected to the image filling module. It is used to determine whether the entire image has been fully restored based on the video frame size defined by the ICD and the number of lines written. If so, the corresponding position of the image buffer valid flag register is set to valid.

5. The digital video receiving and control system based on an airborne hybrid fiber optic link according to claim 1, characterized in that, The predetermined scheduling strategy is either round-robin scheduling or event-driven scheduling.

6. The digital video receiving and control system based on an airborne hybrid fiber optic link according to claim 1, characterized in that, The framing rules are determined based on at least one of the video resolution, frame format, and frame frequency parameters defined by the ICD.

7. A digital video receiving control method based on an airborne hybrid fiber optic link, applied to the system described in any one of claims 1 to 6, characterized in that, Includes the following steps: S1. Set the fiber channel active status, framing rules, receive buffer depth, and initial status of related flag registers according to the ICD. S2. The receiving and scheduling management unit receives video data frames from each valid fiber optic channel MAC unit according to the predetermined scheduling strategy. S3. The line image framing unit determines in real time whether the video data frame sequence received from the receiving scheduling management unit is continuous. If it is, it proceeds to S4; otherwise, it discards the current incomplete frame sequence and returns to S2 to wait for new video data frames. S4. The line image framing unit parses and reassembles the received video data frames according to the pre-configured framing rules to recover the complete video line data. When reassembling the first line of video line data of the current video frame, it generates the first line arrival signal and sends it to the image recovery unit through the first line arrival output terminal. S5. The receiving buffer management unit writes the video line data output by the line image framing unit into the receiving buffer and updates the receiving buffer status flag and the corresponding line image logical ID linked list. S6. The image restoration unit responds to the first line arrival signal in real time. According to the video source identifier indicated by the first line arrival signal, it reads each video line data from the receiving buffer in the order of the row image logical ID linked list of all optical fiber channels corresponding to the video source, and writes the read video line data into the image buffer corresponding to the video source to restore the complete video image. S7. In real time, determine whether the entire image has been restored. If it has been restored, set the corresponding position of the image buffer valid flag register to valid, and the processing of the current video frame ends. Otherwise, return to S6 to continue reading video line data.

8. The digital video receiving control method based on an airborne hybrid fiber optic link according to claim 7, characterized in that, In S3, the method for determining whether a video data frame sequence is continuous is as follows: by checking the frame count or timestamp information of the video data frame, it is determined whether the currently received video data frame is continuous with the previous video data frame; if the frame count is continuous or the timestamp increases and the interval is less than or equal to a preset threshold, it is determined to be continuous; otherwise, it is determined to be discontinuous.

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