Airborne video telemetering system and method for adaptive error correction code parameter adjustment

Abstract

The invention relates to a self-adaptive error correction code parameter adjustment airborne video telemetering system and a self-adaptive error correction code parameter adjustment airborne video telemetering method. The telemetering system comprises a video acquisition module, a video compression coding module, a PCM coding module containing error correction codes, an airborne transmitting and receiving module, a ground transmitting and receiving module, a telemetering link quality evaluation module, a PCM decoding module containing error correction codes and a video compression decoding module. The quality of a telemetering link is evaluated by judging the quality of a telemetering video picture through a ground monitoring system, and when the quality of the telemetering link is reduced, an encoding system automatically adjusts error correction code parameters and the code rate of video encoding, so that the quality of the telemetering downloaded video picture is ensured as much as possible.

Description

Technical Field

[0001] The invention belongs to the technical field of aviation airborne video acquisition and processing, and in particular relates to an airborne video telemetry system and method for adaptive error correction code parameter adjustment. Background Art

[0002] In flight tests, telemetry is an important means of communication between aircraft and ground monitoring systems. It can transmit flight data to the ground monitoring system in real time, providing decision-making basis for ground commanders, aircraft designers, test pilots, etc. PCM-FM (Pulse Code Modulation-Frequency Modulation) and SOQPSK modulation modes are commonly used telemetry methods. They encode airborne collected information, audio and video into pulse code modulation (PCM) format and wirelessly transmit them to the ground for real-time monitoring. Among them, the video images in the airborne data can intuitively and accurately describe the state of the aircraft, which is an important part of collecting telemetry data. Due to the limited telemetry bandwidth, even the compressed video image frame data volume is usually much larger than the maximum capacity of the PCM frame, so the digital image data that needs to be compressed is PCM encoded before transmission. With the increase in the number of airborne video channels, the resolution and frame rate are getting higher and higher, the limitation of telemetry bandwidth is gradually highlighted, especially when the telemetry link is interfered, the multi-channel telemetry video screen will be affected.

[0003] With the gradual advancement of communication technology, data error correction methods have been widely used in the process of data transmission or recording, including Hamming Code, Reed-Solomon Code (RS Code), Convolutional Code, Low-Density Parity-Check Code (LDPC Code), Turbo Code, etc., which can effectively detect and correct errors introduced by noise or other interference in different application scenarios and channel conditions. Due to the high requirements for the real-time and accuracy of airborne telemetry in flight tests, usually only RS code and convolutional code are more applicable. Their error correction ability is related to the proportion of error correction code in the transmitted data, that is, the larger the proportion of check bits, the stronger the error correction ability. Due to the limited bandwidth of the telemetry link, it is impossible to set more check bits. If the check bits are set to be less, it is difficult to adapt to the situation where the number of erroneous data caused by the instability of the telemetry link changes at any time. Summary of the invention

[0004] The purpose of the present invention is to propose an airborne video telemetry system and method with adaptive error correction code parameter adjustment, in which the quality of the telemetry link is evaluated by judging the quality of the telemetry video image through a ground monitoring system. When the quality of the telemetry link decreases, the encoding system automatically adjusts the error correction code parameters and the bit rate of the video encoding to ensure the quality of the telemetry downlink video image as much as possible.

[0005] Technical solution of the present invention: In order to achieve the above-mentioned purpose of the invention, according to the first aspect of the present invention, an airborne video telemetry system with adaptive error correction code parameter adjustment is proposed, comprising: a video acquisition module, a video compression encoding module, a PCM encoding module containing an error correction code, an airborne transmitting and receiving module, a ground transmitting and receiving module, a telemetry link quality evaluation module, a PCM decoding module containing an error correction code, and a video compression decoding module; the video acquisition module receives various types of multi-channel video signals output by an onboard video source, and performs format conversion to obtain a unified original digital video code stream; the video compression encoding module compresses and encodes the original digital video code stream; the PCM encoding module containing an error correction code receives the compressed video code stream output by the video compression encoding module, splits the compressed video data into multiple video data packets according to the error correction code, and then performs error correction code encoding on each video data packet, and then encapsulates the error correction code encoding packet into a PCM encoding data packet and outputs it to the airborne transmitting and receiving module ; The airborne transmitting and receiving module and the ground transmitting and receiving module form a telemetry link for air-to-ground transmission of telemetry data and command status data; the PCM decoding module containing the error correction code reversely decodes the PCM encoded data received by the ground transmitting and receiving module according to the data packet message protocol definition, and then performs decoding processing according to the error correction code encoding parameters to obtain an error-corrected video image data packet, and then recombine the video image data packet to obtain a complete compressed video code stream frame image; the video compression decoding module performs compression decoding according to the compression format of the video compression encoding module to obtain a decoded video image that can be displayed and processed, and sends the decoded video image to the telemetry link quality evaluation module, and the telemetry link quality evaluation module transmits the telemetry link quality evaluation result to the airborne PCM encoding module containing the error correction code through the telemetry uplink, and the PCM encoding module containing the error correction code adjusts the error correction code in real time according to the telemetry link quality evaluation result.

[0006] In a possible embodiment, the video acquisition module uses a DSP chip or an FPGA to perform data acquisition and format conversion to obtain a unified original digital video code stream.

[0007] In a possible embodiment, the video compression encoding module uses a DSP chip or a SoC chip to perform hard encoding of the H.264 / H.265 compression encoding format.

[0008] In a possible embodiment, the error correction code selected by the PCM encoding module containing the error correction code is the RS error correction code, that is, the forward error correction code.

[0009] In a possible embodiment, the size of the RS error correction code check bit is adjusted according to the telemetry link quality result.

[0010] According to a second aspect of the present invention, an airborne video telemetry method for adaptive error correction code parameter adjustment is provided, which adopts the above-mentioned airborne video telemetry system for adaptive error correction code parameter adjustment, and comprises the following steps:

[0011] Step 1: Collect various multi-channel video signals output by the video source on the machine;

[0012] Step 2: compress and encode the original digital video code stream output by the video acquisition module;

[0013] Step 3: Select the multi-channel compressed video code stream in step 2, split the compressed video data into multiple video data packets according to the error correction code size, then perform error correction code encoding on each video data packet, and then encapsulate the error correction code encoded packet into a PCM encoded data packet; the first error correction code encoding is performed according to the initial configuration of the system; the parameters of the subsequent error correction code encoding are processed according to the adjusted error correction code encoding parameters output in step 10 or step 11;

[0014] Step 4: Transmit the PCM coded data packet containing the error correction code from the airborne to the ground via the telemetry link;

[0015] Step 5: According to the current error correction code encoding parameters, the error correction code is decoded to obtain the error-corrected video image data packet, and then the error-corrected video image data packet is reassembled to obtain a complete compressed video code stream frame image;

[0016] Step 6: Perform compression decoding according to the compression format in step 2 to obtain a decoded video image that can be displayed and processed; and display the decoded video to achieve real-time monitoring of the onboard status.

[0017] Step 7: Use a full-reference video quality assessment algorithm based on deep learning or a no-reference video quality assessment algorithm based on deep learning to assess the image quality of the video image decoded in step 6, and obtain the video quality assessment result VQA of each telemetry transmission. i , C<WQA i <1, i=1…n, where n is the number of channels for telemetry downlink video;

[0018] Step 8: According to the video quality assessment result VQA of each telemetry transmission in step 7, the telemetry link quality assessment result TQA is calculated as follows:

[0019]

[0020] Among them, Thrd is the variance threshold, which is set and adjusted according to the system runtime effect; m is VQA i Mean, v is VQA i variance;

[0021] Step 9: Adjust the error correction code according to the telemetry link quality assessment result TQA. When the telemetry link quality assessment result TQA is less than the set low quality threshold, the error correction capability of the error correction code is improved, and the process goes to step 10. Otherwise, determine whether to reduce the error correction capability of the error correction code. When the current error correction capability is used for a period of time T and the telemetry link quality assessment result TQA remains greater than the set high quality threshold during this period, the error correction capability of the error correction code is reduced, and the process goes to step 11.

[0022] Step 10: Improve the error correction capability of the error correction code by increasing the size or proportion of the Parity part in the error correction code encoding parameters;

[0023] Step 11: Reduce the error correction capability of the error correction code by reducing the size or proportion of the Parity part in the error correction code encoding parameters.

[0024] In a possible embodiment, in step three, RS error correction code is used.

[0025] In one possible embodiment, in step seven, when there are a large number of accumulated video data sets and a sufficient number of videos whose quality is degraded after being received and transmitted due to poor telemetry link quality are also sufficient, the video data recorded onboard is used as lossless source video data and the videos with degraded quality are used as damaged videos to establish a training data set, and a full-reference video quality assessment algorithm based on deep learning is used to implement video image quality assessment; when the system is initially used and the accumulated video data is small and a reference video training data set cannot be established, a no-reference video quality assessment algorithm based on deep learning is used to implement video image quality assessment.

[0026] In a possible embodiment, in step 10 and step 11, the size of the video data portion in the initial error correction code parameter is S v , the parity part size is S p , increase or decrease the size of the adjusted parity part

[0027] In one possible embodiment, the size of the adjusted video data portion is increased or decreased. Increase or decrease the adjusted compression bitrate Wherein B is the initial compression coding bit rate, and step 2 uses the adjusted compression bit rate B′ for subsequent compression coding.

[0028] The advantages of the present invention are as follows: the quality of the telemetry link is evaluated by judging the quality of the telemetry video picture through the ground monitoring system; when the quality of the telemetry link decreases, the encoding system automatically adjusts the error correction code parameters and the bit rate of the video encoding to ensure the quality of the telemetry downlink video picture as much as possible. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 It is a structural schematic diagram of an airborne video telemetry system with adaptive error correction code parameter adjustment according to a preferred embodiment of the present invention;

[0030] Figure 2 The present invention is a flowchart of an airborne video telemetry method for adaptively adjusting error correction code parameters according to a preferred embodiment of the present invention. DETAILED DESCRIPTION

[0031] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are 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 making creative work are within the scope of protection of the present invention.

[0032] The features and illustrative embodiments of various aspects of the present invention will be described in detail below. In the detailed description below, many specific details are proposed to provide a comprehensive understanding of the present invention. However, it is obvious to those skilled in the art that the present invention can be implemented without the need for some of these specific details. The following description of the embodiments is only to provide a better understanding of the present invention by illustrating examples of the present invention. The present invention is by no means limited to any specific settings and methods proposed below, but covers any improvements, replacements and modifications of structures, methods, devices without departing from the spirit of the present invention. In the accompanying drawings and the following description, known structures and technologies are not shown to avoid unnecessary ambiguity in the present invention.

[0033] It should be noted that, in the absence of conflict, the embodiments of the present invention and the features in the embodiments can be combined with each other, and the embodiments can refer to and quote each other. The present invention will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0034] like Figure 1 As shown, the present invention proposes an airborne video telemetry system with adaptive error correction code parameter adjustment, comprising: a video acquisition module, a video compression encoding module, a PCM encoding module containing an error correction code, an airborne transmitting and receiving module, a ground transmitting and receiving module, a telemetry link quality evaluation module, a PCM decoding module containing an error correction code, a video compression decoding module, and a video display unit;

[0035] The video acquisition module receives various multi-channel video signals output by the video source on the receiver and performs time synchronization. The received input video stream can be an analog signal or a digital signal. Common video formats include: PAL, VGA, LVDS, DVI, SDI, GigE, etc. For videos of various formats, a mature DSP chip or FPGA can be used for data acquisition and format conversion to obtain a unified digital video code stream.

[0036] The video compression encoding module compresses and encodes the original digital video code stream output by the video acquisition module. The commonly used H.264 / H.265 compression encoding format can be hard-coded using a mature DSP chip or SoC chip. Among them, the video compression encoding module can receive control instructions to adjust the compression method to adjust the bit rate of the compressed video code stream, such as VBR, CBR, CVBR compression methods; if the compressed bit rate is still large, the module can reduce the video image resolution or frame rate before compression to meet the PCM telemetry channel bandwidth requirements.

[0037] The PCM encoding module containing error correction code receives the compressed video code stream output by the video compression encoding module, selects multiple channels of video according to the configuration, splits each frame of the compressed video data into multiple video data packets, and then performs error correction code encoding on each video data packet, preferably RS error correction code (forward error correction code) encoding, and then encapsulates the RS encoded packet into a PCM data packet, and writes the auxiliary information of the video data (such as acquisition time, channel number, video type, etc.) into the data packet message, and outputs the PCM data packet to the airborne transmitting and receiving module for telemetry modulation and transmission of data. The specific PCM encoding method and message format can refer to the implementation method in the document "Airborne Multi-channel Video PCM Telemetry Transmission Technology. Zhang Jie, Zou Qiang, Yan Hui. Computer and Digital Engineering. Issue 5, 2013. p805-807". Among them, the PCM encoding module containing the error correction code receives the PCM telemetry link quality evaluation value output by the onboard transmitting and receiving module, and adjusts the size of the RS error correction code check bit (parity part) and the bit rate of each selected video channel according to the quality of the telemetry link, so as to improve or reduce the error correction capability of the RS encoding according to the quality of the telemetry link, and ensure the availability of the video picture quality of the telemetry downlink as much as possible.

[0038] The airborne transmitting and receiving module and the ground transmitting and receiving module are air-to-ground radio frequency communication systems for air-to-ground transmission of telemetry data and command status data. For example, the PCM-FM and SOQPSK telemetry transmission systems recommended by the US IRIG106 standard. GPS or Beidou navigation communication links can also be used to supplement the uplink to improve the smoothness of the uplink and downlink.

[0039] The PCM decoding module containing the error correction code reversely decodes the PCM encoded data received on the ground according to the data packet message protocol definition, and then performs decoding processing according to the RS encoding parameters to obtain the error-corrected video image data packet, and then recombine the video image data packet to obtain a complete compressed video code stream frame image, that is, the H.264 / H.265 video code stream.

[0040] The video compression and decoding module compresses and decodes the H.264 / H.265 video code stream after PCM decoding to obtain a video image that can be displayed and processed, and sends the processed video image to the telemetry link quality evaluation module and the video display unit.

[0041] Preferably, the PCM decoding module containing the error correction code and the video compression decoding module are run on the ground, and can be implemented by software programming on a computer, or by using an FPGA embedded system.

[0042] The telemetry link quality evaluation module synchronously receives the video image output by the video compression decoding module, measures the quality of the telemetry link by evaluating the quality of the video image, and outputs the telemetry link quality evaluation result to the ground transmitting and receiving module, which is transmitted to the airborne PCM encoding module containing the error correction code through the telemetry uplink, as the basis for adjusting the RS error correction code encoding parameters and the basis for adjusting the code rate of the video compression encoding module.

[0043] In one possible embodiment, according to different stages of system application, a combination of two types of video quality evaluation models is used to implement the video quality evaluation of the telemetry transmission. At the same time, according to the characteristics of the degradation of the telemetry link quality, the telemetry link quality evaluation result is inferred from the video quality evaluation result.

[0044] Based on the above system, the flowchart of the airborne video telemetry method for realizing adaptive error correction code parameter adjustment is as follows: Figure 2 As shown:

[0045] The present invention proposes an airborne video telemetry method for adaptive error correction code parameter adjustment, and adopts the airborne video telemetry system for adaptive error correction code parameter adjustment, and the specific steps are as follows:

[0046] Step 1: Collect various video signals output by the video source on the machine; obtain data and convert the formats of various formats of videos on the machine, and perform time synchronization to obtain a unified digital video code stream;

[0047] Step 2: compress and encode the original digital video code stream output by the video acquisition module; during the first compression encoding, compress according to the video resolution or frame rate and code rate determined by the initial configuration of the telemetry system; the parameters of subsequent compression encoding are compressed according to the encoding parameters output in step ten or step eleven.

[0048] Preferably, step 2 is implemented using H.264 or H.265 compression encoding format.

[0049] Step 3: RS error correction code encoding; select multiple compressed video streams in step 2 according to the configuration, split the compressed video data into multiple video data packets according to the RS error correction code size, and then perform RS error correction code encoding on each video data packet. The first RS encoding is performed according to the initial configuration of the system, for example, according to RS (204, 188), where the size of the video data part is 188 bytes and the size of the parity part is 16 bytes; the parameters of the subsequent RS encoding are processed according to the RS encoding parameters output in step 10 or step 11 to achieve adaptive adjustment of the error correction code parameters.

[0050] Among them, the RS error correction code is implemented by using the existing generator polynomial calculation, which will not be described in detail.

[0051] Step 4: PCM encoding, transmission, and decoding to transmit the PCM video code stream containing error correction code from the airborne to the ground.

[0052] Step 5: RS error correction code decoding. According to the current RS error correction code encoding parameters, RS error correction code decoding is performed to obtain the corrected video image data packet, including calculating the correction factor, using the Berlekamp-Massey algorithm or the Euclid algorithm to calculate the error position polynomial and then using the Chien search algorithm to find the error position and calculate the error value. RS error correction code decoding is an existing method and will not be described in detail.

[0053] Step 6: Compressed video decoding. The video data packets after RS ​​error correction obtained in step 5 are reassembled and compressed and decoded according to the compression format in step 2 to obtain a video image that can be displayed and processed, and the decoded video is displayed to achieve real-time monitoring of the onboard status.

[0054] Step seven: video image evaluation. Perform image quality evaluation on each channel of video images compressed and decoded in step six to obtain evaluation results. Preferably, if there are a large number of accumulated video data sets, and the number of videos whose quality is degraded after being received and transmitted due to poor telemetry link quality is sufficient, the video data recorded on board can be used as lossless source video data and the degraded video as damaged video to establish a training data set, and a full-reference video quality assessment algorithm based on deep learning can be used to implement video image quality assessment, such as DVQA, DeepVQA and other models. When the system is initially used and the accumulated video data is small and a reference video training data set cannot be established, a no-reference video quality assessment algorithm based on deep learning can be used to implement video image quality assessment, such as Patch-VQ, VSFA and other models.

[0055] Video quality assessment results VQA of each telemetry transmission channel i , 0<VQA<1, i=1…n, where n is the number of channels for telemetry downlink video.

[0056] Step 8: Telemetry link quality assessment. Based on the video quality assessment results VQA of each telemetry link in step 6 i , to calculate the telemetry link quality assessment value. In order to avoid misjudging that the quality of the downlink video is degraded due to problems with the original video data of some video channels, it can be considered that the telemetry link quality problem is determined only when the video image quality of all downlink video channel data degrades. Specifically, the telemetry link quality assessment result TQA is calculated as follows:

[0057]

[0058] Among them, Thrd is the variance threshold, which is set and adjusted according to the system runtime effect; m is VQA i Mean, v is VQA i variance.

[0059] Step nine: Determine whether the error correction capability of the RS error correction code needs to be increased or decreased based on the telemetry link quality assessment result TQA. When the telemetry link quality assessment result TQA is less than the set low quality threshold, the error correction capability of the RS error correction code is increased, and the process goes to step ten; otherwise, continue to determine whether to reduce the error correction capability of the RS error correction code. When the system runs with high RS error correction capability for a period of time T and the telemetry link quality assessment result TQA remains greater than the set high quality threshold during this period, the error correction capability of the RS error correction code is reduced, and the process goes to step eleven. Otherwise, the RS error correction code parameters are not adjusted. The limit time T and the high quality threshold of the telemetry link quality assessment can be set according to the on-site application conditions. For example, the limit time T is set to 2 minutes and the high quality threshold of the telemetry link quality assessment is set to 0.9.

[0060] Step 10: Determine the RS encoding parameters and compression coding bit rate when improving the RS error correction capability. According to the telemetry link quality assessment result TQA, adjust and increase the Parity part size or proportion in the RS encoding parameters, and reduce the compression bit rate according to the adjusted data part size in the RS encoding. Specifically, for example, the RS error correction code format initially set is RS (204, 188), that is, the video data part size S v 188 bytes, the parity part size is S p 16 bytes, the size of the adjusted parity part Adjusted video data portion size S′ pand as the parameters adjusted by RS encoding, sent to step 3 for subsequent RS encoding; the adjusted compression bit rate Wherein B is the compression coding bit rate before adjustment, and B′ is sent to step 2 for subsequent compression coding parameters.

[0061] Step 11: Determine the RS coding parameters and compression coding rate when reducing the RS error correction capability. Adjust and reduce the size or proportion of the Parity part in the RS coding parameters according to the telemetry link quality assessment result TQA, and increase the compression code rate according to the size of the data part in the adjusted RS coding. The specific calculation method is the same as step 10, and will not be repeated. The adjusted RS coding parameters are sent to step 3 as the parameters for subsequent RS coding, and the adjusted compression coding rate is sent to step 2 as the parameters for subsequent compression coding.

Claims

1. An airborne video telemetry system with adaptive error correction code parameter adjustment, characterized in that: include: Video acquisition module, video compression encoding module, PCM encoding module with error correction code, airborne transmitting and receiving module, ground transmitting and receiving module, telemetry link quality evaluation module, PCM decoding module with error correction code, video compression decoding module; the video acquisition module receives various multi-channel video signals output by the video source on the receiver, and performs format conversion to obtain a unified original digital video code stream; The video compression encoding module compresses and encodes the original digital video code stream; The PCM encoding module containing error correction code receives the compressed video code stream output by the video compression encoding module, splits the compressed video data into multiple video data packets according to the error correction code, and then encodes each video data packet with error correction code, and then encapsulates the error correction code encoded packet into a PCM encoded data packet and outputs it to the airborne transmitting and receiving module; The airborne transmitting and receiving module and the ground transmitting and receiving module form a telemetry link for air-to-ground transmission of telemetry data and command status data; the PCM decoding module containing error correction code reversely decodes the PCM encoded data received by the ground transmitting and receiving module according to the data packet message protocol definition, and then performs decoding processing according to the error correction code encoding parameters to obtain an error-corrected video image data packet, and then recombine the video image data packet to obtain a complete compressed video code stream frame image; the video compression decoding module performs compression decoding according to the compression format of the video compression encoding module to obtain a decoded video image that can be displayed and processed, and sends the decoded video image to the telemetry link quality evaluation module, and the telemetry link quality evaluation module transmits the telemetry link quality evaluation result to the airborne PCM encoding module containing error correction code through the telemetry uplink, and the PCM encoding module containing error correction code adjusts the error correction code in real time according to the telemetry link quality evaluation result.

2. The airborne video telemetry system with adaptive error correction code parameter adjustment according to claim 1, characterized in that: The video acquisition module uses a DSP chip or an FPGA to acquire data and convert the format to obtain a unified original digital video code stream.

3. The airborne video telemetry system with adaptive error correction code parameter adjustment according to claim 1, characterized in that: The video compression encoding module uses a DSP chip or a SoC chip to perform hard encoding of the H.264 / H.265 compression encoding format.

4. The airborne video telemetry system with adaptive error correction code parameter adjustment according to claim 1, characterized in that: The error correction code selected by the PCM encoding module containing the error correction code is the RS error correction code, that is, the forward error correction code.

5. The airborne video telemetry system with adaptive error correction code parameter adjustment according to claim 4, characterized in that: The size of the RS error correction code check bit is adjusted according to the telemetry link quality results.

6. An airborne video telemetry method with adaptive error correction code parameter adjustment, using an airborne video telemetry system with adaptive error correction code parameter adjustment according to any one of claims 1 to 5, characterized in that: The steps include: Step 1: Collect various multi-channel video signals output by the video source on the machine; Step 2: compress and encode the original digital video code stream output by the video acquisition module; Step 3: Select the multi-channel compressed video code stream in step 2, split the compressed video data into multiple video data packets according to the error correction code size, then perform error correction code encoding on each video data packet, and then encapsulate the error correction code encoded packet into a PCM encoded data packet; the first error correction code encoding is performed according to the initial configuration of the system; the parameters of the subsequent error correction code encoding are processed according to the adjusted error correction code encoding parameters output in step 10 or step 11; Step 4: Transmit the PCM coded data packet containing the error correction code from the airborne to the ground via the telemetry link; Step 5: According to the current error correction code encoding parameters, the error correction code is decoded to obtain the error-corrected video image data packet, and then the error-corrected video image data packet is reassembled to obtain a complete compressed video code stream frame image; Step 6: Perform compression decoding according to the compression format in step 2 to obtain a decoded video image that can be displayed and processed; The decoded video is displayed to achieve real-time monitoring of the onboard status. Step 7: Use a full-reference video quality assessment algorithm based on deep learning or a no-reference video quality assessment algorithm based on deep learning to assess the image quality of the video image decoded in step 6, and obtain the video quality assessment result VQA of each telemetry transmission. i , 0 <VQA i <1, i=1…n, where n is the number of channels for telemetry downlink video; Step 8: Based on the video quality assessment results VQA of each telemetry channel in step 7 i , calculate the telemetry link quality assessment result TQA as follows: Among them, Thrd is the variance threshold, which is set and adjusted according to the system runtime effect; m is VQA i Mean, v is VQA i variance; Step 9: Adjust the error correction code according to the telemetry link quality assessment result TQA. When the telemetry link quality assessment result TQA is less than the set low quality threshold, the error correction capability of the error correction code is improved, and the process goes to step 10. Otherwise, determine whether to reduce the error correction capability of the error correction code. When the current error correction capability is used for a period of time T and the telemetry link quality assessment result TQA remains greater than the set high quality threshold during this period, the error correction capability of the error correction code is reduced, and the process goes to step 11. Step 10: Improve the error correction capability of the error correction code by increasing the size or proportion of the Parity part in the error correction code encoding parameters; Step 11: Reduce the error correction capability of the error correction code by reducing the size or proportion of the Parity part in the error correction code encoding parameters.

7. The airborne video telemetry method for adaptive error correction code parameter adjustment according to claim 6, characterized in that: In the step three, RS error correction code is used.

8. The airborne video telemetry method for adaptive error correction code parameter adjustment according to any one of claims 6 or 7, characterized in that: In step seven, when the accumulated video data set is large and the number of videos whose quality is degraded after being received and transmitted due to poor telemetry link quality is sufficient, the video data recorded on board is used as lossless source video data and the videos with degraded quality are used as damaged videos to establish a training data set, and a full-reference video quality assessment algorithm based on deep learning is used to implement video image quality assessment; When the system is initially used and the accumulated video data is small and it is impossible to establish a reference video training data set, a no-reference video quality assessment algorithm based on deep learning is used to implement video image quality assessment.

9. The airborne video telemetry method for adaptive error correction code parameter adjustment according to any one of claims 6 or 7, characterized in that: In step 10 and step 11, the size of the video data portion in the initial error correction code parameter is S v , the parity part size is S p , increase or decrease the size of the adjusted parity part 10. The airborne video telemetry method for adaptive error correction code parameter adjustment according to claim 9, characterized in that: Increase or decrease the adjusted video data portion size S′ v =S v +S p -S′ p , increase or decrease the adjusted compression bitrate Wherein B is the initial compression coding bit rate, and step 2 uses the adjusted compression bit rate B′ for subsequent compression coding.

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