Low-orbit satellite communication terminal for power grid and video transmission method

Abstract

The invention relates to the technical field of video transmission, in particular to a low-orbit satellite communication terminal for a power grid and a video transmission method, and the method comprises the steps: collecting a visible light video and an infrared video of a power transmission line of the power grid; determining the content redundancy of each frame of visible light video according to the ratio of the power transmission line in each frame of visible light video and the similarity between each frame of visible light video and the adjacent frame of video; calculating the transmission importance degree of each frame of visible light video; and comparing the relative transmission importance of each frame of visible light video to be transmitted and the video frame of the low-orbit satellite cache region, and determining the transmission importance of each frame of visible light video to be transmitted according to the saturation condition of the low-orbit satellite cache region at the corresponding moment of each frame of visible light video to be transmitted, the communication quality in the historical time period and the transmission importance. And evaluating the transmission priority of each frame of visible light video to be transmitted to the low-orbit satellite. Therefore, the transmission quality and efficiency of the video stream are effectively improved.

Description

Technical Field

[0001] This application relates to the field of video transmission technology, specifically to a low-orbit satellite communication terminal and video transmission method for power grids. Background Technology

[0002] With the booming development of the power industry, electrical equipment is being upgraded more frequently, making operation, maintenance, and repair tasks increasingly important in the daily work of the power system. In remote areas or work areas with weak communication infrastructure, although technologies such as drone inspections or fixed-point video surveillance have been gradually introduced, video transmission data is still subject to delays, interruptions, or even loss due to unstable or insufficient ground communication signals, seriously affecting the quality of inspections. Therefore, combining video inspection transmission with low-orbit satellites is of great significance for improving the real-time performance of remote power grid inspections and ensuring the safe and stable operation of the power grid.

[0003] In video surveillance inspections of power transmission lines in remote areas, the time-varying nature of low-Earth orbit satellite communication links and their limited onboard buffer capacity, coupled with the large volume of high-definition inspection video data, easily leads to buffer overflow when network communication signals are weak, thus affecting the effectiveness of video surveillance inspections. To avoid video frame loss due to buffer overflow, existing technologies typically utilize the DropTail algorithm in video surveillance processing equipment to discard video frames. However, existing technologies do not fully consider that after reaching a threshold, the DropTail algorithm has an equal probability of discarding each subsequent video frame. This may result in the discarding of critical video frames during power grid inspections, severely impacting the video quality at the decoding end and leading to poor video transmission performance. Summary of the Invention

[0004] To address the aforementioned technical problems, the purpose of this application is to provide a low-orbit satellite communication terminal and video transmission method for power grids. The specific technical solution adopted is as follows: In a first aspect, embodiments of this application provide a low-orbit satellite video transmission method for power grids, the method comprising the following steps: Collect visible light and infrared video of the power grid's transmission lines; The content redundancy of each visible light video frame is determined by the proportion of power transmission lines in each frame and the similarity between each visible light video frame and its adjacent frames. Based on the degree of temperature difference in the transmission line area in the infrared video, and the consistency of line anomaly identification in the visible light video frame and the infrared video frame at the same time, combined with the content redundancy, the transmission importance of each frame of visible light video is calculated. The relative importance of the transmission of each frame of visible light video to be transmitted is compared with that of the video frames in the low-Earth orbit satellite buffer. The transmission priority of each frame of visible light video to be transmitted to the low-Earth orbit satellite is evaluated by using the saturation status of the low-Earth orbit satellite buffer at the corresponding time, the communication quality in the historical time period, and the aforementioned transmission importance.

[0005] In one embodiment, determining the content redundancy of each frame of visible light video includes: Determine the minimum image similarity between each frame of visible light video and its preceding and following adjacent frames. Based on the minimum value and the proportion of the transmission line, calculate the content redundancy of each frame of visible light video.

[0006] In one embodiment, the content redundancy of each frame of visible light video is positively correlated with the minimum value and negatively correlated with the proportion of the transmission line.

[0007] In one embodiment, calculating the transmission importance of each frame of visible light video includes: For each frame of visible light video, determine the dispersion of the brightness values ​​of all pixels in the transmission line area in the infrared video frame at the same time; extract the texture features of each pixel in each frame of visible light video. The transmission importance of each frame of visible light video is obtained by using the similarity between the coordinates of pixels with abnormal texture features in each frame of visible light video and pixels with abnormal brightness in infrared video at the same time, as well as the degree of dispersion and the content redundancy.

[0008] In one embodiment, the similarity between the coordinates is calculated using Jaccard similarity.

[0009] In one embodiment, obtaining the transmission importance of each frame of visible light video includes: Calculate the product of the Jaccard similarity and the degree of dispersion, perform zero-value protection processing on the content redundancy, and the transmission importance of each frame of visible light video is the ratio of the product to the result of the zero-value protection processing.

[0010] In one embodiment, the evaluation of the transmission priority of each frame of visible light video to be transmitted to a low-Earth orbit satellite includes: A threshold segmentation algorithm is used to obtain the segmentation threshold of the transmission importance of all video frames in the low-orbit satellite buffer. If the transmission importance of the visible light video frame to be transmitted is less than or equal to the segmentation threshold, the transmission priority of the visible light video frame is evaluated using the saturation condition, the communication quality, and the transmission importance. Otherwise, the transmission priority of the visible light video frame to be transmitted is its transmission importance.

[0011] In one embodiment, the transmission priority of visible light video frames is evaluated using the saturation condition, the communication quality, and the transmission importance, specifically as follows: Determine the percentage of the low-orbit satellite buffer capacity that has been occupied at the corresponding time for the visible light video frame to be transmitted, and record it as the buffer percentage. Calculate the average packet loss rate of a preset number of historical video images of the visible light video frame to be transmitted, and calculate the sum of the buffer percentage and the average. The summation is used as the exponent of an exponential function with the natural constant as the base. The ratio of the transmission importance of the visible light video frame to be transmitted to the calculation result of the exponential function is used as the transmission priority of the visible light video frame to be transmitted.

[0012] In one embodiment, the visible light video to be transmitted is transmitted in descending order of transmission priority, and the DropTail algorithm is used to discard video frames.

[0013] Secondly, embodiments of this application also provide a low-orbit satellite communication terminal for power grids, the communication terminal comprising a shell, communication components, and functional units, specifically: The outer shell includes a bottom plate, a top cover, and a sealing ring. The bottom plate and the top cover are fastened together by screws to form a sealed cavity. The sealing ring is installed between the bottom plate and the top cover. The communication components are located inside the housing and include a communication main control circuit board, a communication top plate, a dual-frequency communication antenna and a communication feed post. The dual-frequency communication antenna is located on the outside of the communication top plate, and its feed end is electrically connected to the corresponding feed transceiver end on the communication main control circuit board via the communication feed post. The functional unit includes a video transmission processing unit, wherein the video transmission processing unit is used to evaluate the transmission priority of each frame of visible light video to be transmitted to a low-Earth orbit satellite.

[0014] This application has at least the following beneficial effects: This application calculates the content redundancy of each visible light video frame, effectively identifying repetitive and unnecessary parts. This helps reduce the transmission of redundant data, saves bandwidth resources, improves the efficiency of low-Earth orbit satellite transmission, reduces the transmission of useless data, and ensures that limited bandwidth can prioritize the transmission of important monitoring information, effectively improving the quality and transmission rate of the video stream. Based on the temperature difference in the transmission line area in the infrared video and the consistency of line anomaly identification between the visible light video frame and the infrared video frame at the same time, combined with the content redundancy, the transmission importance of each visible light video frame is calculated. This allows key video frames to be transmitted first, and the transmission priority can be dynamically adjusted according to the importance of the video content, thereby ensuring that monitoring data at important moments is not delayed due to network congestion or satellite buffering issues, improving the reliability of power grid transmission line inspections. By combining the saturation of the low-Earth orbit satellite buffer and historical communication quality, the allocation of buffer resources can be intelligently determined. By combining infrared and visible light video, and especially through the analysis of video frames based on temperature differences and line anomaly identification, more detailed monitoring of power grid transmission line status can be provided. When transmission lines experience overheating, faults, or anomalies, infrared video can accurately capture temperature changes and combine them with visible light video content, ensuring accurate fault detection and helping to identify potential faults in advance, thus improving the safety and stability of the power grid. This avoids wasting or overloading cache resources, reducing unnecessary video transmissions and transmitting only critical information. This solves the problem of limited bandwidth for low-Earth orbit satellites. Through intelligent video content filtering and transmission priority judgment, power grid monitoring can still efficiently transmit critical data even with limited bandwidth resources, improving the accuracy and timeliness of monitoring, thereby enhancing the overall performance of satellite communication. Attached Figure Description

[0015] To more clearly illustrate the technical solutions and advantages in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0016] Figure 1 This is a flowchart illustrating the steps of a low-orbit satellite video transmission method for power grids, provided as an embodiment of this application. Detailed Implementation

[0017] To further illustrate the technical means and effects adopted by this application to achieve the intended purpose of the invention, the following, in conjunction with the accompanying drawings and preferred embodiments, details the specific implementation, structure, features, and effects of a low-orbit satellite communication terminal and video transmission method for power grids proposed in this application. In the following description, different "one embodiment" or "another embodiment" do not necessarily refer to the same embodiment. Furthermore, specific features, structures, or characteristics in one or more embodiments can be combined in any suitable form.

[0018] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains.

[0019] The following description, in conjunction with the accompanying drawings, details a specific scheme for a low-orbit satellite communication terminal and video transmission method for power grids provided in this application.

[0020] Please see Figure 1 The diagram illustrates a flowchart of a low-Earth orbit satellite video transmission method for power grids according to an embodiment of this application. The method includes the following steps: S1 collects visible light and infrared video of the power grid's transmission lines.

[0021] In the power grid transmission line inspection area, this embodiment uses high-definition cameras and infrared cameras to perform real-time video monitoring of the target transmission line. The monitoring video frame rate is 60fps, and the resolution is no less than 720P. The acquired high-definition video stream and infrared video stream are segmented into frames. It should be noted that the field of view of the high-definition camera and the infrared camera need to be calibrated and aligned to ensure that the monitoring area of ​​the visible light video and the infrared video is consistent. This embodiment uses a common optical path design for alignment. Implementers can choose other alignment methods, such as mechanical fixing, or perforation method. The common optical path design for alignment is a well-known existing technology, and the specific process will not be described in detail.

[0022] Simultaneously, the percentage of the low-Earth orbit satellite buffer capacity occupied is obtained in real time through a low-Earth orbit satellite communication terminal and recorded as the buffer percentage; and packet loss rate data fed back from the satellite transmission network is obtained in real time through RTCP technology. Both the buffer percentage and packet loss rate are collected synchronously at a frequency of 60Hz. Implementers can set these frequencies according to their actual needs; this embodiment does not impose any restrictions on this.

[0023] S2. The content redundancy of each visible light video frame is determined by the proportion of power transmission lines in each frame and the similarity between each visible light video frame and its adjacent frames.

[0024] During intelligent inspection of power transmission lines, the large volume of raw video stream data collected by high-definition cameras, coupled with the limited power consumption and size of low-orbit satellites, restricts the transmission buffer capacity. Therefore, indiscriminately buffering all video frames can easily lead to buffer overflow and the loss of crucial video frames, severely impacting the inspection effectiveness of power transmission lines. Consequently, it is necessary to analyze the information carried in each video frame to assess its importance and determine whether frames can be discarded. This ensures that critical video content is not lost, thereby improving the overall stability of the inspection video transmission.

[0025] In power transmission lines, areas where multiple circuits intersect are structurally complex and experience concentrated stress, making them critical areas prone to failure. In contrast, straight lines are relatively stable with lower risk. Furthermore, since the monitored area is fixed during video inspection, the interactive areas of power transmission lines occupy a larger area in the image compared to straight areas. Therefore, this embodiment assesses the importance of a frame image by analyzing the proportion of power transmission lines within the video frame.

[0026] First, a neural network model is trained using existing video frame data of the same type in the video transmission database. Specifically, visible light video frame images and label data from the database are one-hot encoded and then fed into the neural network for Region of Interest (ROI) extraction. The label data is manually labeled, with transmission line areas and non-transmission line areas represented by the numbers 0 and 1, respectively. This embodiment uses a CNN neural network; implementers can choose other neural networks, such as ResNet18 or YOLO. The optimizer is Adam, and the loss function is cross-entropy loss. The training of the neural network is a well-known existing technique, and the specific process will not be elaborated further.

[0027] Taking the u-th video frame image from the acquired high-definition visible light video stream as an example for analysis, the u-th video frame image is fed into the trained CNN neural network, and the output of the CNN neural network is the visible light transmission line region in the u-th video frame image, denoted as the visible light line image.

[0028] The ratio between the area of ​​the visible light line image in the u-th video frame and the area of ​​the u-th video frame itself is obtained and denoted as the transmission line proportion of the u-th video frame. The transmission line proportion reflects whether the transmission line in the u-th video frame is a complex line; a larger proportion indicates less background redundancy in the u-th video frame, thus increasing its value for transmission line inspection and diagnosis, and making transmission more appropriate. It should be noted that in this embodiment, the image area refers to the number of pixels within the image.

[0029] Furthermore, considering that if the content of the u-th video frame is relatively consistent with that of its adjacent frames, it can reflect that the u-th video frame is less important. The more the content expressed by the u-th video frame can be replaced by other frames, the greater the possibility of it being removed.

[0030] Therefore, the similarity between the u-th video frame and the (u-1)-th video frame, and the similarity between the u-th video frame and the (u+1)-th video frame, are calculated using an image similarity algorithm. The minimum similarity between the two similarity values ​​for the u-th video frame is recorded as the minimum similarity of the u-th video frame. The minimum similarity reflects the degree of content similarity between the u-th video frame and its preceding and following adjacent video frames. The smaller the minimum similarity value, the greater the likelihood that the video content has changed significantly at the u-th video frame, and the greater the importance of the u-th video frame. It should be noted that this embodiment specifically uses the SIFT (Scale-Invariant Feature Transform) algorithm, using the ratio of matching points as the result of image similarity calculation. Implementers can choose other existing feasible image similarity algorithms, and this embodiment does not impose any restrictions on this.

[0031] Furthermore, this embodiment determines the content redundancy of each frame of visible light video, specifically as follows: Taking the u-th visible light video frame as an example, the proportion of transmission lines in the u-th visible light video frame is mapped to a positive number. The ratio of the minimum similarity of the u-th visible light video frame to the positive number is used as the content redundancy of the u-th visible light video frame. It should be noted that the purpose of mapping the proportion of transmission lines to a positive number is to avoid the denominator being 0, which would affect the calculation of the ratio. The mapping method used in this embodiment is: calculate the sum of the proportion of transmission lines and a preset value greater than 0, and use this sum as the positive number. The preset value greater than 0 is set to 0.01 in this embodiment. Implementers can set it according to the actual situation. Implementers can also use other feasible mapping methods, which are not limited in this embodiment.

[0032] Content redundancy reflects the information value of power transmission lines contained in a video frame by measuring the proportion of power transmission lines, and reflects the repetition between a video frame and adjacent video frames by measuring minimum similarity. Content redundancy reflects the degree of redundancy of information within the u-th video frame, and thus reflects the likelihood of it being discarded during video transmission; the higher the content redundancy, the less effective information about power transmission lines is contained in the u-th video frame, the higher the redundancy, and the more suitable it is as a priority for discarding under buffer pressure.

[0033] S3. Based on the temperature difference in the transmission line area in the infrared video and the consistency of line anomaly identification in the visible light video frame and the infrared video frame at the same time, combined with the content redundancy, calculate the transmission importance of each frame of visible light video.

[0034] Since rain, snow, and changes in complex terrain may cause excessive dynamic changes in the power grid monitoring video, which may reduce the accuracy of content redundancy assessment, further analysis is needed.

[0035] Transmission lines are exposed to the natural environment for extended periods, making them susceptible to aging from ultraviolet radiation and abrasion from wind and sand, which can lead to cracking or damage to the insulation layer. Once the insulation layer of a transmission line fails, it can easily cause an increase in local leakage current, resulting in an abnormal rise in the local temperature of the line. Therefore, this embodiment combines the temperature differences in the transmission line area observed in infrared video to further analyze the possibility of a fault in the transmission line and assess whether video frames need to be transmitted.

[0036] Taking the u-th visible light video frame as an example, since the brightness values ​​of different temperature regions in the infrared image differ, the infrared video frame image corresponding to the u-th visible light video frame at the same moment after frame division is denoted as the u-th infrared image. Using the same method as extracting the transmission line region from the visible light video frame, the transmission line region in the u-th infrared image is extracted and denoted as the infrared line image. The infrared line image is converted to HSV image format, and the dispersion of the brightness values ​​of all pixels within the transmission line region in the HSV image format is calculated, denoted as the temperature difference value of the u-th infrared image. The temperature difference value reflects the degree of difference in the temperature distribution of the transmission line in the u-th infrared image; the larger the temperature difference value, the greater the possibility of localized heating in the transmission line, thus indicating that the transmission line is more likely to have a fault and requires image transmission. The dispersion can be calculated using standard deviation, variance, coefficient of variation, etc. This embodiment uses standard deviation as the method for calculating the dispersion.

[0037] Furthermore, for transmission lines with insulation wear, not only will the line temperature at the wear point change in the infrared image, but the line texture features at the wear point will also change significantly in the visible light image. Therefore, by analyzing the consistency between the abnormal temperature area in the infrared image and the area with abnormal texture in the visible light image, we can further analyze whether the transmission line has experienced wear.

[0038] Based on the above analysis, texture features of each pixel in each frame of visible light video are extracted. Specifically, taking any frame of visible light video image as an example, the visible light video image is converted into a grayscale image. Then, a 3×3 window is constructed with each pixel in the grayscale image as the center, and the LBP (Local Binary Pattern) value of each pixel is calculated as the texture feature of each pixel. Implementers can choose other existing feasible texture feature extraction algorithms, such as the MLBP algorithm, etc., and this embodiment does not impose any restrictions on this.

[0039] The texture features of all pixels within the power transmission line area of ​​the visible light video image are used as... The outlier detection algorithm takes as input to identify pixels with abnormal texture changes, denoted as visible light detection pixels. Similarly, the brightness values ​​of all pixels in the infrared line image are used as... The input to the outlier detection algorithm is used to obtain pixels with abnormal brightness changes, which are denoted as infrared detection pixels.

[0040] The coordinate data of the visible light detection pixels in the u-th visible light image and the coordinate data of the infrared detection pixels in the u-th infrared image are obtained respectively. Then, the Jaccard similarity between the two sets of coordinate data is calculated and denoted as the damage consistency of the u-th visible light video. The damage consistency reflects whether the damaged areas of the transmission line are consistent in the visible light and infrared images, thus avoiding misjudgments caused by rain and snow interference. The higher the damage consistency, the more likely the transmission line is to have experienced wear, and the more necessary it is to perform image transmission to achieve high-precision inspection.

[0041] Based on the above analysis, the transmission importance of the u-th frame of visible light video is constructed. The specific expression is: In the formula, Let be the temperature difference value of the u-th frame of the infrared image. Let be the impairment uniformity of the u-th visible light video frame; The content redundancy of the u-th visible light video frame is... The default value is greater than 0. This embodiment uses the result of zero-value protection processing for content redundancy to avoid a denominator of 0. The implementer can set it according to the actual situation, and this embodiment does not impose any restrictions on it.

[0042] Transmission importance reflects the presence of significant local temperature rise in transmission lines through temperature difference values; it distinguishes between actual faults and environmental interference through damage consistency, thereby further assessing the line condition; and it reflects the degree of redundancy of information within video frame images through content redundancy. Transmission importance reflects the criticality of the u-th visible light video frame in the power grid transmission line inspection process. The greater the transmission importance, the greater the possibility of wear and tear on the power grid transmission line in the u-th video frame, the stronger the importance of the video frame, and the greater the need for communication transmission for detection to ensure the stable operation of the power grid.

[0043] S4. Compare the relative importance of the transmission of each frame of visible light video to be transmitted with that of the video frames in the low-Earth orbit satellite buffer. Using the saturation status of the low-Earth orbit satellite buffer at the corresponding time of each frame of visible light video to be transmitted, the communication quality in the historical time period, and the transmission importance, evaluate the transmission priority of each frame of visible light video to be transmitted to the low-Earth orbit satellite.

[0044] Furthermore, a more precise analysis can be conducted by combining the buffer space usage of low-orbit satellites and the network packet loss during satellite communication transmission.

[0045] The percentage of the low-Earth orbit (LEO) satellite's buffer capacity that has been occupied at the same time corresponding to the u-th visible light video frame is denoted as the buffer percentage of the u-th visible light video frame. The buffer percentage reflects the current level of storage resource scarcity on the LEO satellite; a higher buffer percentage indicates that the current buffer is closer to saturation, and it is more necessary to retain important keyframes to prevent buffer overflow and subsequent loss of keyframes.

[0046] Simultaneously, packet loss rate data for a predetermined number of historical visible light video frames corresponding to the u-th frame are acquired, and the average of all acquired packet loss rate data for the u-th frame is calculated and denoted as the link fluctuation of the u-th frame. In this embodiment, the predetermined number is set to 120, but implementers can set it according to actual conditions; this embodiment does not impose any restrictions on this. Link fluctuation reflects the degree of fluctuation in the short-term transmission link before the u-th frame; the greater the link fluctuation, the worse the network quality of image communication, and therefore the more critical frames need to be transmitted to prevent non-critical frames from crowding out limited transmission opportunities. It should be noted that the predetermined number of frames are the sequentially adjacent video frames before the u-th frame.

[0047] Furthermore, by combining the differences in transmission importance between the u-th visible light video frame and the frame images in the low-orbit satellite buffer, the necessity of transmitting the u-th visible light video frame can be further evaluated.

[0048] The transmission importance of all frames within the low-orbit satellite buffer is calculated and used as input to the Otsu thresholding method. The segmentation threshold output by the Otsu thresholding method is denoted as the critical threshold corresponding to the u-th frame of visible light video. The Otsu thresholding method is a well-known existing technology, and implementers may choose other feasible existing thresholding segmentation algorithms; this embodiment does not impose any restrictions on this.

[0049] Based on the above analysis, the transmission priority of the u-th visible light video frame is evaluated, and the specific expression is as follows: In the formula, The transmission priority of the u-th visible light video frame is given by [reference]. Let u be the transmission importance of the u-th visible light video frame. The key threshold corresponding to the u-th frame of the visible light video. Let be the buffer percentage of the u-th visible light video frame. Let be the link fluctuation of the u-th visible light video frame. It is an exponential function with the natural constant e as the base.

[0050] It should be understood that, if If the importance of the u-th visible light video frame is greater than that of multiple frames in the low-orbit satellite buffer, then buffer allocation and communication quality are no longer considered, and the video frame is transmitted directly. The cache percentage reflects the cache occupancy of the satellite cache area; the link fluctuation reflects the short-term communication quality before the transmission of the u-th frame of visible light video.

[0051] Transmission priority reflects the necessity of transmitting video frame images; the higher the transmission priority value, the more important the corresponding video frame is, and the more necessary it is to transmit images for line detection.

[0052] For each frame of visible light video to be transmitted to a low-Earth orbit satellite (LEO satellite), i.e., each acquired frame of visible light video, they are sorted from highest to lowest transmission priority. The DropTail algorithm is used to determine the maximum number of video frames that the LEO satellite can accommodate in the current transmission queue. Finally, the video frames at the top of the sorted list are retained, while the remaining frames are discarded. This ensures reliable transmission of critical video frames under limited bandwidth and buffer variations, thereby guaranteeing the stable operation of the power grid.

[0053] Based on the same inventive concept as the above method, this application also provides a low-orbit satellite communication terminal for power grids. The communication terminal includes a shell, communication components, and functional units, specifically: The outer shell includes a bottom plate, a top cover, and a sealing ring. The bottom plate and the top cover are fastened together by screws to form a sealed cavity. The sealing ring is installed between the bottom plate and the top cover, which serves both as a mechanical seal and as an electromagnetic shield. The communication components are located inside the housing and include a communication main control circuit board, a communication top plate, a dual-frequency communication antenna and a communication feed post. The dual-frequency communication antenna is located on the outside of the communication top plate, and its feed end is electrically connected to the corresponding feed transceiver end on the communication main control circuit board through the communication feed post to form a complete radio frequency path. The functional units include a communication transmission unit, a terminal processing unit, a video transmission processing unit, and a power management unit. The communication transmission unit is equipped with a fast converter and a power amplifier for bidirectional conversion between baseband and radio frequency signals. It eliminates image frequency interference by converting the signal to baseband in one step, thereby avoiding video frame corruption or screen tearing. It also integrates an FPGA processing chip to dynamically switch between QPSK and 16APSK according to network quality, ensuring stable transmission of power grid monitoring video and uninterrupted video streaming. The terminal processing unit integrates a visible light high-definition camera and an infrared camera to collect visible light and infrared video of the power grid's transmission lines. It also has a built-in FPGA and high-performance MCU collaborative architecture to achieve spatiotemporal calibration and pixel-level alignment of dual-mode images, thereby providing data support for determining the transmission priority of subsequent video frames. The video transmission processing unit relies on the interface and computing resources provided by the terminal processing unit to perform video compression encoding on the video stream output by the camera monitoring device, calculate the transmission importance of each frame of visible light video, and evaluate the transmission priority of each frame of visible light video to be transmitted to the low-orbit satellite. The power management unit is used to supply power to the communication terminal and can intelligently switch power supply modes to avoid video loss or transmission failure due to insufficient power.

[0054] It should be noted that the order of the embodiments described above is merely for descriptive purposes and does not represent the superiority or inferiority of the embodiments. Furthermore, specific embodiments of this specification have been described above. Additionally, the processes depicted in the accompanying drawings do not necessarily require a specific or sequential order to achieve the desired results. In some implementations, multitasking and parallel processing are possible or may be advantageous.

[0055] The various embodiments in this specification are described in a progressive manner. The same or similar parts between the various embodiments can be referred to each other. Each embodiment focuses on describing the differences from other embodiments.

[0056] The above description is only a preferred embodiment of this application and is not intended to limit this application. Any modifications, equivalent substitutions, improvements, etc., made within the principles of this application should be included within the protection scope of this application.

Claims

1. A method for low earth orbit satellite video transmission for power grids, characterized in that, The method comprises the following steps: Collecting visible light video and infrared video of a power transmission line of a power grid; Determining content redundancy of each frame of visible light video according to a proportion of the power transmission line in each frame of visible light video and a similarity between each frame of visible light video and a neighboring frame of video; Calculating transmission importance of each frame of visible light video based on a temperature difference degree of a power transmission line region in the infrared video, a consistency degree of line anomaly recognition in the visible light video frame and the infrared video frame at the same time, and the content redundancy; Comparing a relative size of transmission importance of each frame of visible light video to be transmitted and video frames in a low-orbit satellite buffer area, and evaluating transmission priority of each frame of visible light video to be transmitted to the low-orbit satellite by using a saturation condition of the low-orbit satellite buffer area at a corresponding time of each frame of visible light video to be transmitted, a communication quality in a historical time period, and the transmission importance.

2. A low earth orbit satellite video transmission method for power grids as claimed in claim 1 characterized by, The determination of the content redundancy of each frame of visible light video comprises: Determining a minimum value of image similarity of each frame of visible light video and neighboring frames of video before and after the frame, and calculating the content redundancy of each frame of visible light video based on the minimum value and the proportion of the power transmission line.

3. A low earth orbit satellite video transmission method for power grids as claimed in claim 2, characterized by, The content redundancy of each frame of visible light video is positively correlated with the minimum value and negatively correlated with the proportion of the power transmission line.

4. A low earth orbit satellite video transmission method for power grids as claimed in claim 1 characterized by, The calculation of the transmission importance of each frame of visible light video comprises: For each frame of visible light video, determining a dispersion degree of luminance values of all pixel points in a power transmission line region in an infrared video frame at the same time, and extracting texture features of each pixel point in each frame of visible light video; Obtaining the transmission importance of each frame of visible light video by using a similarity between coordinates of pixel points with abnormal texture features in each frame of visible light video and pixel points with abnormal luminance in the infrared video at the same time, and the dispersion degree, the content redundancy.

5. A low earth orbit satellite video transmission method for power grids as claimed in claim 4, characterized by, The similarity between the coordinates is calculated by using a Jaccard similarity.

6. A low earth orbit satellite video transmission method for a power grid as claimed in claim 5, characterized by, The obtaining of the transmission importance of each frame of visible light video comprises: Calculating a product of the Jaccard similarity and the dispersion degree, performing zero-value protection processing on the content redundancy, and taking the transmission importance of each frame of visible light video as a ratio of the product to a result of the zero-value protection processing.

7. A low earth orbit satellite video transmission method for power grids as claimed in claim 1 characterized by, The evaluation of the transmission priority of each frame of visible light video to be transmitted to the low-orbit satellite comprises: Obtaining a segmentation threshold of the transmission importance of all video frames in the low-orbit satellite buffer area by using a threshold segmentation algorithm, and evaluating the transmission priority of the visible light video frame to be transmitted by using the saturation condition, the communication quality, and the transmission importance if the transmission importance of the visible light video frame to be transmitted is less than or equal to the segmentation threshold, or taking the transmission importance of the visible light video frame to be transmitted as the transmission priority if the transmission importance is greater than the segmentation threshold.

8. A low earth orbit satellite video transmission method for a power grid as claimed in claim 7, characterized by, The evaluation of the transmission priority of the visible light video frame by using the saturation condition, the communication quality, and the transmission importance specifically comprises: Determining a percentage of a low-orbit satellite buffer area capacity occupied by the visible light video frame to be transmitted, denoted as a buffer proportion, calculating a mean value of a packet loss rate of a historical preset number of frames of video images of the visible light video frame to be transmitted, and calculating a cumulative sum of the buffer proportion and the mean value. The accumulation is taken as an index of an exponential function with a natural constant as a base number, and a ratio of a transmission importance of the visible light video frame to be transmitted to a calculation result of the exponential function is taken as a transmission priority of the visible light video frame to be transmitted.

9. A low earth orbit satellite video transmission method for a power grid as claimed in claim 8, characterized by, The visible light video to be transmitted is transmitted in a descending order of the transmission priority, and a DropTail algorithm is used for discarding the video frame.

10. A low-orbit satellite communication terminal for power grid, applying the low-orbit satellite video transmission method for power grid in claim 1, characterized in that, The communication terminal comprises a shell, a communication component and a functional unit, specifically: The shell comprises a bottom plate, a top cover and a sealing baffle ring, the bottom plate and the top cover are buckled through screwing to form a closed cavity, and the sealing baffle ring is installed between the bottom plate and the top cover; The communication component is located inside the shell and comprises a communication main control circuit board, a communication top plate, a dual-frequency communication antenna and a communication feed column, the dual-frequency communication antenna is arranged outside the communication top plate, and a feed end of the dual-frequency communication antenna is electrically connected with a corresponding feed transceiving end on the communication main control circuit board through the communication feed column; The functional unit comprises a video transmission processing unit, wherein the video transmission processing unit is used for evaluating a transmission priority of each frame of visible light video to be transmitted to a low earth orbit satellite.

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