A Method and System for Detecting the Timeliness of Video Streams Based on Timed Scheduling

Abstract

The present invention provides a method and system for detecting the timeliness of a video stream based on timed scheduling. By real-time monitoring of the data packet arrival rate and the system service rate in the video stream transmission system, a wide timed scheduling strategy is adopted to ensure that the system transmits stranded data packets in a timely manner under high load conditions, thereby alleviating network congestion problems. On this basis, a timeliness evaluation index TSAoI is introduced. By quantifying the timeliness of the video stream transmission system, the video stream transmission system is guided to dynamically adjust the scheduling cycle according to the actual timeliness requirements, which significantly improves the transmission efficiency and stability of the video stream. According to the requirements of different scenarios, the system can accurately set the scheduling cycle range under loose, low, high and extreme timeliness requirements, thereby achieving flexible adaptation to timeliness requirements. This method effectively solves the problems of poor timeliness and low stability in the video stream transmission system, and provides an efficient and stable video stream transmission solution for different application scenarios.

Description

Technical Field

[0001] The present invention relates to the field of information communication technology, and in particular to a method and system for detecting the timeliness of a video stream based on timing scheduling. Background Art

[0002] In the prior art, the transmission process of video streaming data often causes unstable timeliness problems such as video freezes and frame drops due to network fluctuations or insufficient network carrying capacity. At the same time, with the expansion of video streaming application fields, video streaming media has increasingly higher requirements for the timeliness of data transmission in many application scenarios. For example, in scenarios such as video conferencing, online education, telemedicine, and autonomous driving, the timeliness requirements for video streaming are extremely strict. In these scenarios, excessive delays or video freezes will lead to communication barriers, unsatisfactory teaching results, medical operation errors, and even endanger life safety.

[0003] In order to improve the stability of video stream data transmission and enhance user experience, the application of scheduling methods in the transmission process of video stream data is the current mainstream means. For example, the buffer-based scheduling method dynamically adjusts the buffer size according to the network conditions, and adopts a pre-fetching strategy to download video clips in advance, but this scheduling method is obviously difficult to apply to real-time transmission scenarios of video streams with high timeliness requirements. Another example is the scheduling method based on dynamic bit rate, which achieves stable transmission of video stream data by optimizing the block size, sending multiple resolution streams dynamically switching at the same time, and dynamically discarding the enhancement layer. However, this scheduling method substantially reduces the video quality obtained by the user end and cannot achieve stable high-quality video stream transmission. At the same time, the existing scheduling methods lack quantitative indicators, making it difficult to evaluate the timeliness of video stream transmission and lack of explainability. Summary of the invention

[0004] Purpose of the invention: The first purpose of the present invention is to provide a video stream timeliness detection method based on timed scheduling, which can dynamically adjust the scheduling period according to the quantitative indicators of timeliness; the second purpose is to provide a video stream timeliness detection system based on timed scheduling.

[0005] Technical solution: A method for detecting the timeliness of a video stream based on timed scheduling, comprising the following steps:

[0006] S1, real-time monitoring of the data packet arrival rate and system service rate of the video stream received by the video stream transmission system;

[0007] S2. When it is detected that the system service rate is less than the data packet arrival rate, the video streaming system uses a wide timing scheduling;

[0008] S3, real-time acquisition of the timeliness evaluation index TSAoI of the video stream transmission system, and setting TSAoI thresholds according to different timeliness requirements of the video stream transmission system;

[0009] S4. When the video stream transmission system is under different timeliness requirements, calculate the corresponding timing scheduling period thresholds according to the TSAoI thresholds corresponding to the timeliness requirements and the packet arrival rate collected in real time, and adjust the timing scheduling period of the video stream transmission system to the corresponding timing scheduling period threshold according to the current timeliness requirement.

[0010] Specifically, step S1 includes: monitoring in real time the sequence and time slots corresponding to the video stream packets received by the video stream transmission system, and calculating the corresponding packet arrival rate of the video stream; monitoring in real time the system time length for which the video stream transmission system has completed transmission, and calculating the corresponding system service rate of the video stream.

[0011] Specifically, the formula for calculating the packet arrival rate of the video stream is:

[0012] ,

[0013] In the formula: is the packet arrival rate of the video stream, represents the t-th time slot, is the total number of packets arriving at the t-th time slot, is the number of timing scheduling cycles. When the timing scheduling cycle is not set, set as the fixed parameter 10, represents non-existence.

[0014] Specifically, the formula for calculating the system service rate of the video stream is:

[0015] ,

[0016] In the formula: is the system service rate of the video stream, represents the t-th time slot, is the total number of packets whose transmission has been completed at the t-th time slot; is the number of timing scheduling cycles. When the timing scheduling cycle is not set, set as the fixed parameter 10, represents non-existence.

[0017] Specifically, in step S2, wide timing scheduling includes: increasing the transmission bandwidth of the video stream transmission system at the next time slot, and completing the transmission of the packets remaining in the video stream transmission system within one time slot.

[0018] Specifically, the formula for the timeliness evaluation index TSAoI is:

[0019] ,

[0020] ,

[0021] ,

[0022] In the formula: is the value of the timeliness evaluation index, represents the packet arrival rate of the video stream in the current time slot. For the convenience of representation, use to refer to ; is the probability distribution of the packet arrival interval, is the interval to reach the last packet of the scheduling; is the interval length; is the number of timing scheduling cycles; is the positive real number obtained by rounding down the quotient of the interval length and the timing scheduling period; is the remainder of the division of the interval length by the timing scheduling period; is the interval from the last packet of the scheduling to the trigger scheduling, is expectation of, is expectation of, is and product expectation of, represents is and function of.

[0023] Specifically, the timeliness requirements of the video stream transmission system include loose timeliness, low timeliness, high timeliness, and extreme timeliness.

[0024] Specifically, in step S4, under the loose timeliness requirement, substitute the TSAoI threshold corresponding to the loose timeliness requirement and the packet arrival rate collected in real time into the calculation formula of TSAoI, and calculate the corresponding loose timing scheduling period threshold ;

[0025] Under the low timeliness requirement, substitute the TSAoI threshold corresponding to the low timeliness requirement and the packet arrival rate collected in real time into the calculation formula of TSAoI, and calculate the corresponding lower limit of the low timing scheduling period , the low timing scheduling period threshold ;

[0026] Under the high timeliness requirement, substitute the TSAoI threshold corresponding to the high timeliness requirement and the packet arrival rate collected in real time into the calculation formula of TSAoI, and calculate the corresponding lower limit of the high timing scheduling period , the high timing scheduling period threshold ;

[0027] Under the requirement of extreme timeliness, the TSAoI threshold corresponding to the extreme timeliness requirement and the packet arrival rate collected in real time are substituted into the calculation formula of TSAoI, and the corresponding extreme timing scheduling period threshold is calculated. 。

[0028] Specifically, in step S4, the loose timing scheduling period threshold :

[0029] ,

[0030] In the formula: is the TSAoI threshold corresponding to the loose timeliness requirement, represents the calculation formula of the timeliness evaluation index. Substitute and the packet arrival rate collected in real time into 's calculation formula, and solve to obtain ;

[0031] The lower limit of the low timing scheduling period :

[0032] ,

[0033] In the formula: is the TSAoI threshold corresponding to the low timeliness requirement;

[0034] The lower limit of the high timing scheduling period :

[0035] ,

[0036] In the formula: is the TSAoI threshold corresponding to the high timeliness requirement;

[0037] The extreme timing scheduling period threshold :

[0038] ,

[0039] In the formula: is the TSAoI threshold corresponding to the extreme timeliness requirement.

[0040] The present invention also provides a video stream timeliness detection system based on timing scheduling, including:

[0041] Data monitoring module: used to monitor the packet arrival rate and system service rate of the video stream received by the video stream transmission system in real time;

[0042] Wide timing scheduling module: used to perform a wide timing scheduling once on the video stream transmission system when it is detected that the system service rate is less than the packet arrival rate;

[0043] Timeliness evaluation index monitoring module: used to collect the timeliness evaluation index TSAoI of the video stream transmission system in real time, and set the TSAoI threshold according to the different timeliness requirements of the video stream transmission system;

[0044] Scheduling cycle adjustment module: When the video stream transmission system is in different timeliness requirements, the timing scheduling cycle thresholds corresponding to the different timeliness requirements are calculated according to the TSAoI threshold corresponding to the timeliness requirement and the real-time collected data packet arrival rate, and the timing scheduling cycle of the video stream transmission system is adjusted to the corresponding timing scheduling cycle threshold according to the current timeliness requirement.

[0045] Beneficial effects: Compared with the prior art, the significant effects of the present invention are: the present invention introduces a timing scheduling mechanism and a timeliness evaluation index TSAoI (Timed Scheduling Age of Information) in the video stream transmission system. In the video stream transmission system, by real-time monitoring of the data packet arrival rate and the system service rate, a wide timing scheduling strategy is adopted to ensure that the system transmits the stranded data packets in time under high load conditions, which fundamentally alleviates the network congestion problem. In addition, the TSAoI index is innovatively proposed, which can quantify the timeliness of the video stream transmission system, guide the video stream transmission system to dynamically adjust the scheduling cycle according to the actual timeliness requirements, and significantly improve the transmission efficiency and stability of the video stream. According to the requirements of different scenarios, the system can accurately set the scheduling cycle range under loose, low, high and extreme timeliness requirements, thereby realizing flexible adaptation to timeliness requirements. This method effectively solves the problems of poor timeliness and low stability in the video stream transmission system, and has good versatility and operability. It provides an efficient and stable video stream transmission solution for different application scenarios, and provides technical support for the theoretical research and practical application of data stream transmission. BRIEF DESCRIPTION OF THE DRAWINGS

[0046] Figure 1 It is a flow chart of the method of the present invention.

[0047] Figure 2 It is a schematic diagram of the sampling line of the real-time data packet arrival rate and the system service rate of the video stream transmission system of the present invention.

[0048] Figure 3 It is a schematic diagram of the timeliness of scheduled scheduling under four timeliness requirements of the present invention. DETAILED DESCRIPTION

[0049] The present invention is further described below in conjunction with the accompanying drawings.

[0050] Example 1

[0051] See also Figure 1As shown in the figure, this embodiment provides a method for detecting the timeliness of video streams based on timed scheduling, including the following steps:

[0052] S1. Monitor the packet arrival rate and system service rate of the video stream received by the video stream transmission system in real time.

[0053] To obtain the packet arrival rate of the video stream, monitor the sequence and time slot number corresponding to the video stream packets received by the video stream system in real time, and record it as the arrival situation matrix :

[0054] ,

[0055] ,

[0056] In the formula: represents contains l timed scheduling periods, is the total number of packets arriving at the t-th time slot; is the element corresponding to the i-th row and j-th column in; is the arrival time slot corresponding to the k(l - 1)-th packet at the end of the (l - 1)-th timed scheduling period; is the number of timed scheduling periods, and the number of packets arriving in B time slots must not be greater than the scheduling period; represents the arrival time slot corresponding to the a-th packet; the arrival situation matrix the 0 at the corresponding position in indicates that no packet arrives at the system at this time slot.

[0057] According to the arrival situation matrix , the calculation formula for the packet arrival rate of the video stream is obtained as:

[0058] ,

[0059] In the formula: is the packet arrival rate of the video stream, represents the t-th time slot. When the timed scheduling period is not set, set as the fixed parameter 10, represents non-existence.

[0060] To obtain the system service rate of the video stream, monitor the system time length of the video stream system transmission completion in real time, and record it as the service duration matrix :

[0061] ,

[0062] ,

[0063] Wherein: is the total number of data packets transmitted and completed at the t-th time slot; is the element corresponding to the i-th row and j-th column in; is the system service duration corresponding to the k(l - 1)-th data packet at the end of the (l - 1)-th timing scheduling period; is the system service duration corresponding to the a-th data packet; The 0 at the corresponding position in indicates that no data packet is completed and served by the system in this time slot.

[0064] According to the service duration matrix , the calculation formula for the system service rate of the video stream is:

[0065] ,

[0066] Wherein: is the system service rate of the video stream.

[0067] Please refer to Figure 2 as shown, sample the real-time data packet arrival rate and system service rate of the video stream transmission system. In this embodiment, the sampling time slot interval is [35, 44], B = 10, and the corresponding sampling arrival situation matrix is as shown in Table 1 below.

[0068] Table 1

[0069] t 35 36 37 38 39 40 41 42 43 44 N(t) 0 22 0 0 23 0 24 25 26 27

[0070] As can be seen from Table 1, at the 35th, 37th, 38th, and 40th time slots, no data packets arrive at the system, and 6 data packets arrive from the 35th time slot to the 44th time slot.

[0071] The corresponding sampling service duration matrix is as shown in Table 2 below.

[0072] Table 2

[0073] t 35 36 37 38 39 40 41 42 43 44 T(t) 0 3 0 0 2 0 4 6 9 11

[0074] As can be seen from Table 2, from the 36th to the 40th time slots, the system is in an intermittent working mode, and starting from the 41st time slot, the service rate of the system begins to be less than the arrival rate of data packets, and the system time of the data packets gradually increases.

[0075] The system state information of the sampling time slots is obtained from the data packet arrival rate formula and the system service rate formula as shown in Table 3 below.

[0076] Table 3

[0077] t 35 36 37 38 39 40 41 42 43 44 <![CDATA[P Ar (t)]]> 0.4 0.45 0.5 0.3 0.6 0.3 0.6 0.9 0.8 0.8 <![CDATA[P Se (t)]]> 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5

[0078] It can be seen from Table 3 that after the 41st time slot, the system service rate is stably less than the data packet arrival rate, and data packet retention occurs in the system, greatly reducing the timeliness of the video stream received at the destination node.

[0079] S2. When it is monitored that the system service rate is less than the data packet arrival rate, the video stream transmission system uses a wide timing schedule once.

[0080] Specifically, monitor the real-time data packet arrival rate and system service rate of the video stream. When the data packet arrival rate is higher than the system service rate, the system uses a wide timing schedule once, increases the system transmission bandwidth at the next time slot, and completes the transmission of the data packets retained by the video stream transmission system in one time slot, preparing for the subsequent introduction of the timeliness index and scheduling method of the timing schedule information.

[0081] S3. Collect the timeliness evaluation index TSAoI of the video stream transmission system in real time, and set the TSAoI threshold according to different timeliness requirements of the video stream transmission system.

[0082] In the present invention, the timeliness index TSAoI of the information flow transmission system is introduced to evaluate the timeliness of the system. The construction and calculation of TSAoI are described below.

[0083] For the simplicity of the formula, let: , represents the data packet arrival rate of the current time slot, and the probability distribution of the data packet arrival interval is:

[0084] ,

[0085] In the formula: is the probability distribution of the data packet arrival interval, is the interval to reach the last packet of the schedule; is the interval length; is the number of timing schedule periods; is the positive real number obtained by rounding down the quotient of the interval length and the timing schedule period; is the remainder of the division of the interval length by the timing schedule period.

[0086] Furthermore, the expected value of the corresponding intermediate variable is obtained:

[0087] ,

[0088] In the formula: is the interval from the last packet of the schedule to the trigger schedule, is the expectation of, is the expectation of, is the expectation of the product.

[0089] Construct the calculation formula of TSAoI through the expected values of the above intermediate variables:

[0090] ,

[0091] In the formula: is the value of the timeliness evaluation index, represents that the timeliness evaluation index TSAoI is a function of the data packet arrival rate and the timing scheduling period ; the smaller the value of TSAoI, the higher the timeliness of the information received at the destination node, and the fresher the video stream; the larger the value of TSAoI, the lower the timeliness of the information received at the destination node, and the older the video stream.

[0092] According to the real-time collected data packet arrival rate , the corresponding real-time system timeliness index TSAoI value can be obtained.

[0093] S4. When the video stream transmission system is under different timeliness requirements, according to the TSAoI threshold corresponding to the timeliness requirement and the real-time collected data packet arrival rate, calculate the timing scheduling period threshold corresponding to different timeliness requirements respectively, and adjust the timing scheduling period of the video stream transmission system to the corresponding timing scheduling period threshold according to the current timeliness requirement.

[0094] In this embodiment, the timeliness requirements of the video stream transmission system are respectively defined as: loose timeliness, low timeliness, high timeliness, and extreme timeliness.

[0095] S41. Under the loose timeliness requirement, substitute the TSAoI threshold corresponding to the loose timeliness requirement and the real-time collected data packet arrival rate into the calculation formula of TSAoI, and calculate the corresponding loose timing scheduling period threshold :

[0096] ,

[0097] In the formula: is the TSAoI threshold corresponding to the loose timeliness requirement, represents the calculation formula of the timeliness evaluation index, that is, by substituting and the real-time collected data packet arrival rate into 's calculation formula, calculate the timing scheduling period, that is, 's value.

[0098] S42. Under low timeliness requirements, substitute the TSAoI threshold corresponding to the low timeliness requirements and the packet arrival rate collected in real time into the calculation formula of TSAoI to calculate the corresponding lower limit of the low timing scheduling period , and then obtain the low timing scheduling period threshold .

[0099] ,

[0100] In the formula: is the TSAoI threshold corresponding to the low timeliness requirements, and the lower limit of the low timing scheduling period is obtained based on the same calculation method as the loose timing scheduling period threshold .

[0101] S43. Under high timeliness requirements, substitute the TSAoI threshold corresponding to the high timeliness requirements and the packet arrival rate collected in real time into the calculation formula of TSAoI to calculate the corresponding lower limit of the high timing scheduling period , and then obtain the high timing scheduling period threshold .

[0102] ,

[0103] In the formula: is the TSAoI threshold corresponding to the high timeliness requirements, and the lower limit of the high timing scheduling period is obtained based on the same calculation method as the loose timing scheduling period threshold .

[0104] S44. Under extreme timeliness requirements, substitute the TSAoI threshold corresponding to the extreme timeliness requirements and the packet arrival rate collected in real time into the calculation formula of TSAoI to calculate the corresponding extreme timing scheduling period threshold :

[0105] ,

[0106] In the formula: is the TSAoI threshold corresponding to the extreme timeliness requirements, and the extreme timing scheduling period threshold is obtained based on the same calculation method as the loose timing scheduling period threshold . The extreme timing scheduling period threshold is the upper limit of the frequency of the system scheduling period, and the extreme timing scheduling period threshold corresponds to the highest value of the timeliness of the data stream transmission system .

[0107] The application of this method in a specific scenario will be described below.

[0108] In this embodiment, , and the corresponding ; , obtain the corresponding low timing scheduling period threshold according to the formula ; , obtain the corresponding high timing scheduling period threshold according to the formula ; , obtain the corresponding limit timing scheduling period threshold according to the formula .

[0109] In this embodiment, 200 time slots are used as the design frequency, and the timeliness requirement of the system is periodically changed to obtain Figure 3 the TSAoI change curve shown in, and it can be clearly seen from Figure 3 that as the timeliness level of the system increases, the timing scheduling period becomes smaller and smaller, the TSAoI peak value of the system becomes lower and lower, and the corresponding timeliness of the system becomes better and better. Due to the limit of the system energy consumption, the limit timing scheduling period of the system is that more frequent timing scheduling will consume more resources and energy and will exceed the system load.

[0110] The method provided by the present invention can quickly switch the timing scheduling period according to the timeliness requirement, so as to adjust the system timeliness, and an effective strategy for quantitatively measuring and quickly regulating the timeliness of the video stream transmission system is obtained through the TSAoI index and the timing scheduling means.

[0111] Embodiment 2

[0112] This embodiment provides a video stream timeliness detection system based on timing scheduling. This system corresponds to the video stream timeliness detection method based on timing scheduling described in Embodiment 1 and includes the following modules:

[0113] Data monitoring module: used to monitor the packet arrival rate and system service rate of the video stream received by the video stream transmission system in real time;

[0114] Wide timing scheduling module: used to make the video stream transmission system use a wide timing scheduling once when it is detected that the system service rate is less than the packet arrival rate;

[0115] Timeliness evaluation index monitoring module: used to collect the timeliness evaluation index TSAoI of the video stream transmission system in real time and set the TSAoI threshold according to different timeliness requirements of the video stream transmission system;

[0116] Scheduling period adjustment module: when the video stream transmission system is under different timeliness requirements, calculate the corresponding timing scheduling period threshold according to the TSAoI threshold corresponding to the timeliness requirement and the packet arrival rate collected in real time, and adjust the timing scheduling period of the video stream transmission system to the corresponding timing scheduling period threshold according to the current timeliness requirement.

Claims

1. A video stream timeliness detection method based on timed scheduling, characterized in that: The following steps are involved: S1, real-time monitoring of the data packet arrival rate and system service rate of the video stream received by the video stream transmission system; S2. When it is detected that the system service rate is less than the data packet arrival rate, the video streaming system uses a wide timing scheduling; S3, real-time acquisition of the timeliness evaluation index TSAoI of the video stream transmission system, and setting TSAoI thresholds according to different timeliness requirements of the video stream transmission system; the timeliness evaluation index TSAoI formula is: ， ， ， Where: is the value of the timeliness evaluation index, Represents the packet arrival rate of the video stream in the current time slot. For ease of representation, Reference ; is the probability distribution of packet arrival interval, To reach the last packet interval of the scheduling; is the interval length; is the number of scheduled scheduling cycles; It is a positive real number obtained by rounding down the quotient of the interval length and the timing scheduling period; It is the remainder of the interval length divided by the timing scheduling period; To schedule the last data packet to trigger the scheduling interval, for expectations, for expectations, for and The expectation of the product, represent yes and Function of S4. When the video stream transmission system is in different timeliness requirements, the timing scheduling cycle thresholds corresponding to the different timeliness requirements are calculated according to the TSAoI threshold corresponding to the timeliness requirement and the real-time collected data packet arrival rate, and the timing scheduling cycle of the video stream transmission system is adjusted to the corresponding timing scheduling cycle threshold according to the current timeliness requirement.

2. The video stream timeliness detection method according to claim 1, characterized in that: The step S1 includes: real-time monitoring of the sequence and time slot number corresponding to the video stream data packets received by the video stream transmission system, and calculating the corresponding video stream data packet arrival rate; real-time monitoring of the system time length for the video stream transmission system to complete the transmission, and calculating the corresponding video stream system service rate.

3. The video stream timeliness detection method according to claim 2, characterized in that: The data packet arrival rate calculation formula of the video stream is: ， Where: is the packet arrival rate of the video stream, represents the tth time slot, is the total number of packets arriving at the tth time slot, The number of scheduled scheduling cycles. When the scheduled scheduling cycle is not set, set is a fixed parameter of 10, Represents does not exist.

4. The video stream timeliness detection method according to claim 2, characterized in that: The system service rate calculation formula of the video stream is: ， Where: is the system service rate of the video stream, represents the tth time slot, is the total number of data packets transmitted at the tth time slot; The number of scheduled scheduling cycles. When the scheduled scheduling cycle is not set, set is a fixed parameter of 10, Represents does not exist.

5. The video stream timeliness detection method according to claim 1, characterized in that: In the step S2, the wide timing scheduling includes: increasing the transmission bandwidth of the video stream transmission system at the next time slot, and completing the transmission of the retained data packets in the video stream transmission system in one time slot.

6. The video stream timeliness detection method according to claim 1, characterized in that: The timeliness requirements of the video stream transmission system include loose timeliness, low timeliness, high timeliness and extreme timeliness.

7. The video stream timeliness detection method according to claim 6, characterized in that: In step S4, under the relaxed timeliness requirement, the TSAoI threshold corresponding to the relaxed timeliness requirement and the real-time collected data packet arrival rate are substituted into the TSAoI calculation formula to calculate the corresponding relaxed timing scheduling period threshold ; Under low timeliness requirements, the TSAoI threshold corresponding to the low timeliness requirements and the real-time collected data packet arrival rate are substituted into the TSAoI calculation formula to calculate the corresponding low timing scheduling cycle lower limit. , low timing scheduling cycle threshold ; Under the high timeliness requirement, the TSAoI threshold corresponding to the high timeliness requirement and the real-time collected data packet arrival rate are substituted into the TSAoI calculation formula to calculate the corresponding high timing scheduling cycle lower limit. , high timing scheduling cycle threshold ; Under the extreme timeliness requirement, the TSAoI threshold corresponding to the extreme timeliness requirement and the real-time collected data packet arrival rate are substituted into the TSAoI calculation formula to calculate the corresponding extreme timing scheduling cycle threshold. .

8. The video stream timeliness detection method according to claim 7, characterized in that: In step S4, the loose timing scheduling cycle threshold : ， Where: is the TSAoI threshold corresponding to the relaxed timeliness requirement, Represents the calculation formula of timeliness evaluation index, and the real-time data packet arrival rate Bring in The calculation formula is solved to get ; Low scheduled scheduling cycle lower limit : ， Where: is the TSAoI threshold corresponding to the low timeliness requirement; High timing scheduling cycle lower limit : ， Where: TSAoI threshold corresponding to high timeliness requirement; Extreme timing scheduling cycle threshold : ， Where: is the TSAoI threshold corresponding to the extreme timeliness requirement.

9. A video stream timeliness detection system based on timed scheduling, characterized in that: include: Data monitoring module: used to monitor the data packet arrival rate and system service rate of the video stream received by the video stream transmission system in real time; Wide timing scheduling module: used for the video stream transmission system to use wide timing scheduling when it is detected that the system service rate is less than the data packet arrival rate; Timeliness evaluation index monitoring module: used for real-time acquisition of the timeliness evaluation index TSAoI of the video stream transmission system, and setting TSAoI thresholds according to different timeliness requirements of the video stream transmission system; the timeliness evaluation index TSAoI formula is: ， ， ， Where: is the value of the timeliness evaluation index, Represents the packet arrival rate of the video stream in the current time slot. For ease of representation, Reference ; is the probability distribution of packet arrival interval, To reach the last packet interval of the scheduling; is the interval length; is the number of scheduled scheduling cycles; It is a positive real number obtained by rounding down the quotient of the interval length and the timing scheduling period; It is the remainder of the interval length divided by the timing scheduling period; To schedule the last data packet to trigger the scheduling interval, for expectations, for expectations, for and The expectation of the product, represent yes and Function of Scheduling cycle adjustment module: When the video stream transmission system is in different timeliness requirements, the timing scheduling cycle thresholds corresponding to the different timeliness requirements are calculated according to the TSAoI threshold corresponding to the timeliness requirement and the real-time collected data packet arrival rate, and the timing scheduling cycle of the video stream transmission system is adjusted to the corresponding timing scheduling cycle threshold according to the current timeliness requirement.

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