Cross-device video synchronous display method

Abstract

The invention discloses a cross-device video synchronous display method, which relates to the technical field of video display, is used for solving the problems of video playing interruption and user experience reduction, and is used for detecting operation behavior data of a field terminal and quantifying the influence of the operation behavior data on the synchronization stability by synchronizing clock references at two ends and establishing a synchronous clock. Analyzing data generation characteristics, generating a drift index after detecting a drift distance of a synchronous clock, judging whether to trigger a transmission regulation and control mechanism by combining the data generation characteristics, and when entering the transmission regulation and control mechanism, acquiring network state data of a field terminal and receiving buffer data in a remote terminal; according to the method, data sending and reading time sequences of a field terminal and a remote terminal are adjusted, frame timestamps at two ends are detected after adjustment, whether a transmission regulation and control mechanism is triggered again or not is judged according to the frame timestamps, self-adaptive synchronous control under network fluctuation is achieved, and frame-level synchronization and playing continuity of a cross-device video in a variable environment are kept.

Description

Technical Field

[0001] This invention relates to the field of video display technology, and more specifically, to a method for cross-device video synchronous display. Background Technology

[0002] With the rapid development of applications such as remote collaboration, online education, virtual meetings, and multi-screen interaction, the demand for cross-device video synchronization is increasing. In existing technologies, methods based on Network Time Protocol (NTP) or local buffering mechanisms are usually used to achieve synchronized video playback across different terminals.

[0003] The existing technology has the following shortcomings: Currently, existing technologies are insufficient in responding to the real-time impact of network fluctuations, differences in terminal performance, and user operation behaviors. This can easily lead to video frame misalignment or playback asynchrony between remote terminals and on-site terminals, affecting the viewing experience and playback continuity of cross-device video. It is also impossible to achieve precise frame-level synchronization and adaptive control in multi-terminal and multi-network environments, resulting in video playback interruption and a decline in user experience. Therefore, a cross-device video synchronization display method is proposed.

[0004] The information disclosed in the background section is only intended to enhance the understanding of the background of this disclosure, and therefore may include information that does not constitute prior art known to those skilled in the art. Summary of the Invention

[0005] To overcome the aforementioned deficiencies of the prior art, embodiments of the present invention provide a cross-device video synchronization display method. This method addresses the problems mentioned in the background art by establishing a synchronization clock using clock references at both ends, detecting and quantifying the operational behavior of on-site terminals, monitoring synchronization clock drift in real time and generating a drift index, dynamically adjusting data transmission timing based on network status and received buffer data, and determining whether to re-trigger the transmission control mechanism based on frame timestamps.

[0006] To achieve the above objectives, the present invention provides the following technical solution: a method for cross-device video synchronization display, comprising the following steps: Step S1: When the field terminal and the remote terminal are connected to the data synchronization system at the same time, synchronize the clock references at both ends and establish a synchronization clock, detect the operation behavior data of the field terminal and analyze the data generation characteristics. Step S2: Obtain the drift of the synchronization clock, and determine whether the transmission control mechanism is triggered based on the data generation characteristics. When the transmission control mechanism is entered, set the statistical time, collect the network status data of the field terminal and the received buffer data in the remote terminal. Step S3: Use network status data to evaluate the link stability index, perform serialization analysis on the received buffer data to generate a dynamic sequence of the buffer, and combine the link stability index to generate transmission timing correction coefficients. Step S4: Adjust the data transmission timing of the field terminal according to the transmission timing correction coefficient. After adjustment, detect the frame timestamps at both ends and determine whether to re-trigger the transmission control mechanism based on the frame timestamps.

[0007] In a preferred embodiment, in step S1, when the field terminal and the remote terminal simultaneously access the data synchronization system, the global time server sends the standard time to the terminal and uses the standard time as the clock reference for both ends. The field terminal and the remote terminal each return their own local time. The time deviation is obtained by subtracting the local time of the terminal from the clock reference. The local time of the terminal is corrected by using time deviation. After the local time of the terminal is consistent with the clock reference, the local time of the terminal is used as the synchronization clock.

[0008] In a preferred embodiment, in step S1, the operation behavior data includes playback control events and interface interaction events, and a preset sampling period is used to monitor the playback control events and interface interaction events of the on-site terminal within the preset sampling period. The frequency of playback control events and interface interaction events is counted as the frequency of playback behavior and the frequency of interaction behavior, respectively. Data generation features are calculated using the frequency of playback behavior and the frequency of interaction behavior.

[0009] In a preferred embodiment, in step S2, when the field terminal and the remote terminal are in the process of video transmission and playback, the time difference between the clock reference and the synchronization clock is obtained as the drift amount of the synchronization clock. Multiple monitoring periods are preset, and the drift index is obtained by comprehensively calculating the drift amount and data generation characteristics in each monitoring period; If the drift index is greater than the preset drift index threshold, the transmission control mechanism is triggered. Conversely, if the transmission control mechanism is not triggered, monitoring will continue. After entering the transmission control mechanism, a preset statistical period is set and divided into multiple statistical times to collect network status data from on-site terminals and receive buffer data from remote terminals.

[0010] In a preferred embodiment, in step S2, the network status data includes uplink bandwidth data and packet loss rate data, and the receive buffer data includes the number of frame backlogs and the playback output rate. The ratio of the total amount of data successfully transmitted by the field terminal to the preset statistical period is used as the uplink bandwidth data; The packet loss rate data is calculated by comparing the packet number sequence sent by the on-site terminal with the received acknowledgment sequence of the remote terminal. The difference between the number of frames entering the buffer and the number of frames being decoded within the preset statistical period is taken as the frame backlog. The ratio of the number of frames successfully output by the playback device within a preset statistical period to the preset statistical period is used as the playback output rate.

[0011] In a preferred embodiment, in step S3, the link stability index is calculated by fusing uplink bandwidth data and packet loss rate data; The buffer state quantity is calculated by combining the number of backlogged frames and the playback output rate. The buffer state quantities at each statistical moment are sorted in chronological order and then combined into a dynamic sequence of the buffer.

[0012] In a preferred embodiment, in step S3, in the buffer dynamic sequence, the buffer state value is obtained by subtracting the buffer state value at the previous statistical time and the buffer state value at the next statistical time. The basic timing correction amount is obtained by multiplying the average value of each buffer state change value by the preset correction sensitivity coefficient. The product of the link stability index and the basic timing correction is used as the transmission timing correction coefficient.

[0013] In a preferred embodiment, in step S4, the video frame timestamps output by the field terminal during video transmission are obtained by the frame timestamp detection unit. The time interval is obtained by subtracting the timestamps of adjacent video frames. The product of the time interval and the transmission timing correction coefficient is used as the timing correction amount. The timing offset is obtained by multiplying the timing correction amount by the preset timing adjustment factor. The target time interval is obtained by summing the timing offset and the time interval, and then input to the transmission control unit of the field terminal to update the data transmission timing of the field terminal.

[0014] In a preferred embodiment, in step S4, after the data transmission timing is adjusted, the timestamps of the output frames of the field terminal and the remote terminal are detected in real time, and the difference between them is used as the frame synchronization offset. If the frame synchronization offset is greater than the preset synchronization offset threshold, the transmission control mechanism will be retried. Conversely, the transmission control mechanism will not be triggered.

[0015] The technical effects and advantages of this invention are as follows: This invention establishes a synchronous clock by synchronizing clock references at both ends, detects operational behavior data of the field terminal and quantifies its impact on synchronization stability, analyzes data generation characteristics, generates a drift index after detecting the drift of the synchronous clock, and determines whether to trigger the transmission control mechanism based on the data generation characteristics. When the transmission control mechanism is activated, network status data of the field terminal and received buffer data in the remote terminal are collected, and the data sending and reading timing of the field terminal and the remote terminal is adjusted. After adjustment, the frame timestamps at both ends are detected, and it is determined whether to re-trigger the transmission control mechanism based on the frame timestamps. This achieves adaptive synchronization control under network fluctuations and maintains frame-level synchronization and playback continuity of cross-device video in changing environments. Attached Figure Description

[0016] Fig. 1 This is a flowchart illustrating the implementation of a cross-device video synchronization display method according to the present invention.

[0017] Fig. 2 This is a schematic diagram illustrating the steps of a cross-device video synchronization display method according to the present invention. Detailed Implementation

[0018] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0019] This invention establishes a synchronous clock by synchronizing clock references at both ends, detects operational behavior data of field terminals and quantifies its impact on synchronization stability, analyzes data generation characteristics, generates a drift index after detecting the drift of the synchronous clock, and determines whether to trigger the transmission control mechanism based on the data generation characteristics. When the transmission control mechanism is activated, network status data of the field terminal and received buffer data in the remote terminal are collected, and the data transmission and reading timing of the field terminal and the remote terminal are adjusted. After adjustment, the frame timestamps at both ends are detected, and it is determined whether to re-trigger the transmission control mechanism based on the frame timestamps, thereby achieving adaptive synchronization control under network fluctuations.

[0020] Example 1, as Figs. 1-2 As shown, a method for cross-device video synchronization display includes the following steps: Step S1: When the field terminal and the remote terminal are connected to the data synchronization system at the same time, synchronize the clock references at both ends and establish a synchronization clock, detect the operation behavior data of the field terminal and analyze the data generation characteristics. Step S2: Obtain the drift of the synchronization clock, and determine whether the transmission control mechanism is triggered based on the data generation characteristics. When the transmission control mechanism is entered, set the statistical time, collect the network status data of the field terminal and the received buffer data in the remote terminal. Step S3: Use network status data to evaluate the link stability index, perform serialization analysis on the received buffer data to generate a dynamic sequence of the buffer, and combine the link stability index to generate transmission timing correction coefficients. Step S4: Adjust the data transmission timing of the field terminal according to the transmission timing correction coefficient. After adjustment, detect the frame timestamps at both ends and determine whether to re-trigger the transmission control mechanism based on the frame timestamps.

[0021] The specific implementation is as follows: In step S1, in cross-device video synchronization scenarios, differences in network latency, clock accuracy, and operational behavior among different terminals can easily lead to image misalignment or audio-visual asynchrony. Therefore, when both the on-site terminal and the remote terminal simultaneously access the data synchronization system, this step first establishes a unified time reference and forms a synchronized clock through clock calibration to ensure that both ends operate under the same time reference. At the same time, the operational behavior of the on-site terminal is detected and its characteristics are analyzed in real time, and the operational behavior is incorporated into the synchronization control logic. In subsequent transmission processes, time deviations caused by operation interruptions or control commands can be identified and corrected in a timely manner.

[0022] When both the field terminal and the remote terminal are connected to the data synchronization system at the same time, the data synchronization system detects the access status, network bandwidth, data interface type and time synchronization capability of both ends through the communication layer protocol. After confirming that both the field terminal and the remote terminal are in a communicable and synchronized state, the system synchronizes the clock references of both ends and establishes a synchronized clock.

[0023] Accessing the data synchronization system refers to the process by which on-site terminals and remote terminals establish a logical connection through network communication protocols, complete identity authentication, and enter a state where they can participate in time synchronization and data interaction.

[0024] The clock reference is a unified time reference standard used to measure the time accuracy and alignment status of each terminal. The global time server sends the standard time to the terminal and uses the standard time as the clock reference at both ends. The local terminal and the remote terminal return their own local time respectively. The time deviation is obtained by subtracting the local time of the terminal from the clock reference.

[0025] After correcting the local time of the terminal using time deviation, a synchronous clock is generated. When the local time of the terminal is faster than the clock reference, the stepping speed of the local clock is slowed down through a delay compensation mechanism. When the local time of the terminal is slower than the clock reference, it is corrected through a micro-stepping acceleration mechanism. After the local time of the terminal is consistent with the clock reference, the local time of the terminal is used as the synchronous clock to ensure that the field terminal and the remote terminal output frame data under the clock reference.

[0026] It should be explained that a global time server is a time control node in a data synchronization system that provides a unified time reference and timing signal, enabling all connected field terminals and remote terminals to operate under a unified time base; the delay compensation mechanism is a dynamic time correction method that reduces the clock step rate by introducing delay; and the micro-stepping acceleration mechanism is a synchronization adjustment method that shortens the timing step size or increases the clock frequency.

[0027] Operational behavior data refers to the behavioral record data related to the timeline or playback status generated by the field terminal during video playback, control, and interaction, including playback control events and interface interaction events.

[0028] Among them, playback control events refer to the user's operation behavior on the video playback process, such as play, pause, fast forward, etc.; interface interaction events refer to the user's operation behavior on the playback interface or playback environment during the viewing process, such as adjusting the volume, switching the resolution, etc.

[0029] A preset sampling period is set, and playback control events and interface interaction events of the on-site terminal are monitored within the preset sampling period. The number of times playback control events and interface interaction events occur are counted as the playback behavior frequency and interaction behavior frequency, respectively. Features are generated by calculating data using the frequency of playback behavior and the frequency of interaction behavior: ,in, Generate features for the data. and For preset weighting coefficients, For playback frequency, Frequency of interactive behavior.

[0030] Data generation characteristics are used to describe the level of terminal operation activity and its impact on time synchronization stability. When the data generation characteristics are small, it indicates that the terminal is in a stable playback state and has little impact on the synchronization clock. When the data generation characteristics are large, it indicates that the terminal is in a state of frequent operation and has a greater impact on the synchronization clock.

[0031] It should be explained that the preset sampling period can be set according to the video frame rate, network refresh cycle, or system clock update frequency; the preset weight coefficient can be set according to the degree of influence of different event types on synchronization stability. For example, if the playback control event has a greater impact on the timeline, then the corresponding weight coefficient will be set to a higher value.

[0032] This step eliminates time differences between different terminals caused by network latency or clock deviation by establishing a clock reference and generating a synchronous clock. Furthermore, by monitoring and quantifying playback control events and interface interaction events within a preset sampling period and calculating data generation characteristics, real-time identification of time disturbances caused by interactive operations is achieved.

[0033] In step S2, when the field terminal and the remote terminal are in the process of video transmission and playback, the time difference between the clock reference and the synchronization clock is obtained as the drift of the synchronization clock, which reflects the stability of the synchronization clock during continuous operation.

[0034] After standardizing the drift amount and data generation characteristics respectively, we obtain the drift amount coefficient and the data generation coefficient. Multiple monitoring periods are preset. Within each monitoring period, the drift coefficient and data generation coefficient are acquired. A drift index is then generated based on the drift coefficient and data generation coefficient. Where E is the drift index, n is the number of monitoring periods, and i is the index, taking values ​​of 1, 2, 3...n. Here, γ is the i-th drift coefficient, and γ is the preset suppression coefficient. Generate coefficients for the data.

[0035] It should be explained that multiple preset monitoring periods can be set according to the system's synchronization accuracy requirements, network fluctuation characteristics, and video frame rate; preset suppression coefficients can be set according to the degree of interference of user operation on time synchronization stability; the standardization processing methods include, but are not limited to, standard linear transformation based on interval scaling, statistical Z-Score standardization method, or normalization method based on nonlinear mapping function. The application methods of standardization processing will not be elaborated here.

[0036] The drift index is compared with a preset drift index threshold to determine whether the transmission control mechanism should be triggered. If the drift index is greater than the preset drift index threshold, it indicates that the synchronous clock has a continuous drift accumulation within multiple cycles, and the transmission control mechanism is triggered; otherwise, the transmission control mechanism is not triggered, and monitoring continues.

[0037] After entering the transmission control mechanism, a preset statistical period is established and divided into multiple statistical time periods. Network status data of the on-site terminals and receive buffer data of the remote terminals are collected. The network status data reflects the bandwidth usage, latency characteristics, and data transmission stability of the network during the current statistical time period. The network status data includes uplink bandwidth data and packet loss rate data. The receive buffer data is used to reflect the operating status and performance characteristics of the remote terminals during the entire process of data reception, buffering, decoding, and playback, including the number of frame backlogs and playback output rate.

[0038] Among them, the ratio of the total amount of data successfully sent by the statistical field terminal to the preset statistical period is used as uplink bandwidth data to reflect the available transmission capacity of the network channel. The packet loss rate data is calculated by comparing the packet number sequence sent by the on-site terminal with the received acknowledgment sequence of the remote terminal. ,in, The number of data packets that the remote terminal successfully received and acknowledged. This represents the total number of data packets sent by the field terminal. Packet loss rate data is used to reflect the transmission reliability of the link; The frame backlog is used to reflect the degree of buffer accumulation at the receiving end and the risk of playback delay. It is obtained by detecting the difference between the number of frames entering and leaving the buffer queue in the remote terminal. The difference between the number of frames entering the buffer and the number of frames being decoded within a preset statistical period is used as the frame backlog. The playback output rate is used to reflect the output stability of the playback terminal and the degree of matching with the input rate. The ratio of the number of frames successfully output by the playback terminal within a preset statistical period to the preset statistical period is used as the playback output rate. It should be explained that the preset statistical period can be set according to system requirements, network stability and volatility, and data transmission characteristics.

[0039] This step enables continuous quantitative monitoring and adaptive adjustment of synchronization clock stability. Over multiple monitoring periods, a drift index is generated to reflect the trend of synchronization accuracy changes, identifying long-term drift accumulation in the synchronization clock. When the drift index exceeds a threshold, the system automatically enters a transmission control mechanism to dynamically adjust the transmission strategy. This ensures that cross-device video maintains time consistency and image continuity even under network fluctuation interference, improving the system's synchronization accuracy and playback stability.

[0040] In step S3, the uplink bandwidth data and packet loss rate data are standardized to obtain the uplink bandwidth coefficient and packet loss rate coefficient, respectively. The ratio of the uplink bandwidth coefficient to the packet loss rate coefficient is used as the link stability index. After standardizing the frame backlog number and playback output rate respectively, the frame backlog coefficient and playback output coefficient are obtained. The ratio of the frame backlog coefficient to the playback output coefficient is used as the buffer state quantity. The buffer state variables at each statistical moment are sorted in chronological order and combined to form a dynamic sequence of the buffer. In the dynamic sequence of the buffer, the buffer state change value is obtained by subtracting the buffer state value at the previous statistical time step from the buffer state value at the next statistical time step. The basic timing correction amount is obtained by multiplying the average value of each buffer state change value by the preset correction sensitivity coefficient. The product of the link stability index and the basic timing correction is used as the transmission timing correction coefficient.

[0041] Transmission timing correction coefficients are used to correct for time deviations in data transmission and reception between field terminals and remote terminals; It should be explained that the preset correction sensitivity coefficient can be set according to the fluctuation range of the terminal's network link and the timing error range.

[0042] This step generates transmission timing correction coefficients to dynamically correct the time deviation between the field terminal and the remote terminal, offsetting the cumulative errors caused by clock drift and link fluctuations, and ensuring the continuity and synchronization of frame-level data during cross-device transmission.

[0043] In step S4, the video frame timestamps output by the field terminal during video transmission are obtained by the frame timestamp detection unit; the time interval is obtained by subtracting the timestamps of adjacent video frames; the product of the time interval and the transmission timing correction coefficient is used as the timing correction amount; the timing correction amount is multiplied by the preset timing adjustment factor to obtain the timing offset amount. The target time interval is obtained by summing the timing offset and the time interval. The target time interval is then input to the transmission control unit of the field terminal to update its data transmission timing.

[0044] It should be explained that the frame timestamp detection unit is used to detect and record the output timestamps of consecutive video frames; the preset timing adjustment factor can be set according to the network link fluctuation characteristics, video frame rate and buffer stability; the transmission control unit is used to receive the target time interval and control the actual time of data packet transmission.

[0045] When the timing offset is positive, it indicates that the current synchronization clock drift is too large or the receiving buffer is under high load, and the field terminal delays the data transmission time; when the timing offset is negative, it indicates that the link is in good condition and the delay is small, and the field terminal sends data packets in advance to make the frame output timing of both ends more consistent. After adjusting the data transmission and reading timing, the timestamps of the output frames of the field terminal and the remote terminal are detected in real time, and the difference between them is used as the frame synchronization offset. Among them, the timestamp of the output frame of the field terminal is used to mark the time when the video frame is encoded and sent at the sending end, and the timestamp of the output frame of the remote terminal is used to mark the time when the same video frame is decoded and played at the receiving end. The frame synchronization offset is compared with a preset synchronization offset threshold to determine whether to re-trigger the transmission control mechanism. If the frame synchronization offset is greater than the preset synchronization offset threshold, the transmission control mechanism will be retried. Conversely, the transmission control mechanism will not be triggered. After the adjustment is completed, when the frame synchronization offset is greater than the preset synchronization offset threshold, the transmission control mechanism is triggered to regenerate the transmission timing correction coefficient. Through this cyclic process, the transmission rhythm is continuously corrected under dynamic network changes to maintain the timing consistency and data synchronization stability between the on-site terminal and the remote terminal.

[0046] It should be explained that the preset synchronization offset threshold can be set according to the video frame rate, network transmission latency characteristics, and playback delay range.

[0047] This step adjusts the data transmission timing of the field terminal by delaying or advancing it according to the positive or negative direction of the transmission timing correction coefficient, and calculates the frame synchronization offset in real time by combining the frame timestamp difference. This continuously optimizes the transmission rhythm when network conditions change dynamically, ensuring the time synchronization accuracy between the field terminal and the remote terminal. Through a continuous loop detection and correction mechanism, the stability and real-time performance of cross-device video synchronization are improved.

[0048] Finally, it should be noted that in this paper, relational terms such as first and second are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations.

[0049] Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0050] In this document, the singular forms “a,” “an,” and “the” may also include the plural forms unless the context clearly indicates otherwise. It should also be understood that terms such as “comprising / including” or “having” specify the presence of the stated features, integrals, steps, operations, components, parts, or combinations thereof, but do not preclude the possibility of the presence or addition of one or more other features, integrals, steps, operations, components, parts, or combinations thereof. Meanwhile, the term “and / or” as used in this specification includes any and all combinations of the associated listed items.

[0051] The various embodiments in this specification are described in a progressive manner. Each embodiment focuses on the differences from other embodiments. The various embodiments can be combined as needed, and the same or similar parts can be referred to each other.

[0052] The above description of the disclosed embodiments will enable those skilled in the art to make or use various modifications to these embodiments. It will be readily apparent to those skilled in the art that the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of this application. Therefore, this application is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A method for cross-device video synchronization display, characterized in that: Includes the following steps: Step S1: When the field terminal and the remote terminal are connected to the data synchronization system at the same time, synchronize the clock references at both ends and establish a synchronization clock, detect the operation behavior data of the field terminal and analyze the data generation characteristics. Step S2: Obtain the drift of the synchronization clock, and determine whether the transmission control mechanism is triggered based on the data generation characteristics. When the transmission control mechanism is entered, set the statistical time, collect the network status data of the field terminal and the received buffer data in the remote terminal. Step S3: Use network status data to evaluate the link stability index, perform serialization analysis on the received buffer data to generate a dynamic sequence of the buffer, and combine the link stability index to generate transmission timing correction coefficients. Step S4: Adjust the data transmission timing of the field terminal according to the transmission timing correction coefficient. After adjustment, detect the frame timestamps at both ends and determine whether to re-trigger the transmission control mechanism based on the frame timestamps.

2. The cross-device video synchronization display method according to claim 1, characterized in that: In step S1, when the field terminal and the remote terminal simultaneously access the data synchronization system, the global time server sends the standard time to the terminal and uses the standard time as the clock reference for both ends. The field terminal and the remote terminal each return their own local time. The time deviation is obtained by subtracting the local time of the terminal from the clock reference. The local time of the terminal is corrected by using time deviation. After the local time of the terminal is consistent with the clock reference, the local time of the terminal is used as the synchronization clock.

3. The cross-device video synchronization display method according to claim 1, characterized in that: In step S1, the operation behavior data includes playback control events and interface interaction events. A preset sampling period is used to monitor the playback control events and interface interaction events of the on-site terminal within the preset sampling period. The frequency of playback control events and interface interaction events is counted as the frequency of playback behavior and the frequency of interaction behavior, respectively. Data generation features are calculated using the frequency of playback behavior and the frequency of interaction behavior.

4. The cross-device video synchronization display method according to claim 1, characterized in that: In step S2, when the field terminal and the remote terminal are in the process of video transmission and playback, the time difference between the clock reference and the synchronization clock is obtained as the drift amount of the synchronization clock. Multiple monitoring periods are preset, and the drift index is obtained by comprehensively calculating the drift amount and data generation characteristics in each monitoring period; If the drift index is greater than the preset drift index threshold, the transmission control mechanism is triggered. Conversely, if the transmission control mechanism is not triggered, monitoring will continue. After entering the transmission control mechanism, a preset statistical period is set and divided into multiple statistical times to collect network status data from on-site terminals and receive buffer data from remote terminals.

5. The cross-device video synchronization display method according to claim 4, characterized in that: In step S2, the network status data includes uplink bandwidth data and packet loss rate data, and the receive buffer data includes the number of frame backlogs and the playback output rate. The ratio of the total amount of data successfully transmitted by the field terminal to the preset statistical period is used as the uplink bandwidth data; The packet loss rate data is calculated by comparing the packet number sequence sent by the on-site terminal with the received acknowledgment sequence of the remote terminal. The difference between the number of frames entering the buffer and the number of frames being decoded within the preset statistical period is taken as the frame backlog. The ratio of the number of frames successfully output by the playback device within a preset statistical period to the preset statistical period is used as the playback output rate.

6. The cross-device video synchronization display method according to claim 5, characterized in that: In step S3, the link stability index is calculated by fusing uplink bandwidth data and packet loss rate data; The buffer state quantity is calculated by combining the number of backlogged frames and the playback output rate. The buffer state quantities at each statistical moment are sorted in chronological order and then combined into a dynamic sequence of the buffer.

7. The cross-device video synchronization display method according to claim 6, characterized in that: In step S3, in the dynamic sequence of the buffer, the buffer state value is obtained by subtracting the buffer state value at the previous statistical time step from the buffer state value at the next statistical time step. The basic timing correction amount is obtained by multiplying the average value of each buffer state change value by the preset correction sensitivity coefficient. The product of the link stability index and the basic timing correction is used as the transmission timing correction coefficient.

8. The cross-device video synchronization display method according to claim 7, characterized in that: In step S4, the video frame timestamps output by the field terminal during video transmission are obtained through the frame timestamp detection unit; The time interval is obtained by subtracting the timestamps of adjacent video frames. The product of the time interval and the transmission timing correction coefficient is used as the timing correction amount. The timing offset is obtained by multiplying the timing correction amount by the preset timing adjustment factor. The target time interval is obtained by summing the timing offset and the time interval, and then input to the transmission control unit of the field terminal to update the data transmission timing of the field terminal.

9. A cross-device video synchronization display method according to claim 8, characterized in that: In step S4, after the data transmission timing is adjusted, the timestamps of the output frames of the field terminal and the remote terminal are detected in real time, and the difference between them is used as the frame synchronization offset. If the frame synchronization offset is greater than the preset synchronization offset threshold, the transmission control mechanism will be retried. Conversely, the transmission control mechanism will not be triggered.

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