Audio and video transmission method and system capable of self-adapting to network bandwidth

Abstract

The invention belongs to the technical field of audio and video transmission, and relates to an audio and video transmission method and system with a self-adaptive network bandwidth, and the method comprises the steps: collecting audio and video signals through an audio and video coding assembly, generating coding data based on preset coding index parameters, and storing the coding data in an audio and video coding cache; millisecond-level real-time bandwidth sensing is realized through a local dynamic bandwidth sampling technology, so that the dependence on feedback of a receiving end is thoroughly eliminated, and the lagging phenomenon caused by delay is radically reduced; and a multi-level network state discrimination mechanism is constructed by further combining the two indexes of the data transmission cache utilization rate and the transmission rate, the network state is refined into four levels, and the strategy is dynamically adjusted, so that the congestion control response precision is remarkably improved. Under a network congestion scene, through intelligent filtering of non-key frames, shortening of an I-frame interval and reduction of redundant data transmission, key picture continuity and audio stream continuity are guaranteed preferentially, and the problems of network burden and service quality reduction caused by traditional full-amount transmission are solved.

Description

Technical Field

[0001] The present invention belongs to the technical field of audio - video transmission, and particularly relates to an audio - video transmission method and system adaptable to network bandwidth. Background Art

[0002] Traditional audio - video transmission schemes are prone to problems such as video freezing and stuttering during network fluctuations. The main reasons include:

[0003] Lag in bitrate adjustment: The bandwidth estimation method (such as RTCP) relying on receiver feedback has a delay and is difficult to respond to network changes in real - time;

[0004] Insufficient data redundancy processing: Non - key frames (such as P - frames) are not dynamically filtered according to the network state, resulting in increased congestion;

[0005] Single - threshold discrimination: Judging the network state only through a single index such as packet loss rate or delay has a high misjudgment rate.

[0006] The existing patent CN114640886B proposes adaptive adjustment based on cache utilization rate, but does not combine frame - level bandwidth prediction; CN119363665A estimates bandwidth through frame bursting technology, but lacks multi - level state classification. Summary of the Invention

[0007] The present invention provides an audio - video transmission method and system adaptable to network bandwidth to solve the problems raised in the background art.

[0008] To achieve the above object, the present invention provides the following technical solutions:

[0009] An audio - video transmission method adaptable to network bandwidth, comprising the following steps:

[0010] S1: Collect audio - video signals through an audio - video encoding component, generate encoded data based on preset encoding index parameters, and store it in the audio - video encoding cache;

[0011] S2: Extract audio - video frames from the audio - video encoding cache for protocol encapsulation, generate packetized data, and store it in the data sending cache;

[0012] S3: Real - time monitor the current utilization rate and sending rate of the data sending cache, and combine with the dynamic bandwidth sampling results to determine that the current network state is one of the following four levels: smooth network, bandwidth warning, insufficient bandwidth, and extremely low bandwidth;

[0013] S4: Dynamically adjust the encoding parameters and / or execute data filtering strategies according to the network state, including:

[0014] When the network state is a bandwidth warning, gradually reduce the encoding bitrate and frame rate according to the gradient rule;

[0015] When the network status is insufficient bandwidth, discard the P frames in the encoded data and shorten the I frame interval;

[0016] When the network status is extremely low bandwidth, discard all video frames and only retain audio frames;

[0017] S5: Send the adjusted packaged data to the receiving end through the adaptive transmission channel.

[0018] As a further solution of the present invention: The dynamic bandwidth sampling includes:

[0019] Based on the frame-level burst technology, calculate the current network bandwidth upper limit through the reception time difference between the first packet and the last packet and the frame size;

[0020] Combined with the network competition model, deduce the average rate of background traffic, and the formula is:

[0021]

[0022] Among them, C is the bandwidth upper limit, S is the sending rate, R is the receiving rate, and B is the average rate of background traffic.

[0023] As a further solution of the present invention: The network status determination specifically includes:

[0024] If the data sending buffer utilization rate ≤ 40% and the sending rate ≥ the preset threshold, it is determined that the network is smooth;

[0025] If the utilization rate is between 40% - 65% and the sending rate continues to decline, it is determined as a bandwidth warning;

[0026] If the utilization rate is between 65% - 85% and the sending rate is lower than 80% of the target bit rate, it is determined as insufficient bandwidth;

[0027] If the utilization rate > 85% and the sending rate is lower than 50% of the target bit rate, it is determined as extremely low bandwidth.

[0028] As a further solution of the present invention: The audio and video encoding buffer is a double-linked list structure. When the buffer reaches the upper limit, discard the data in the oldest I frame interval in chronological order, and append the new encoded data to the end of the list.

[0029] As a further solution of the present invention: The data filtering strategy further includes:

[0030] In the extremely low network state, give priority to retaining audio frames and synchronize decoding based on the audio timestamp;

[0031] When the bandwidth is restored, gradually restore the encoding bit rate and the I frame interval according to the gradient rule.

[0032] An audio and video transmission system with adaptive network bandwidth, including:

[0033] Audio and video encoding module: used to collect and encode audio and video signals, and generate encoded data for storage in the audio and video encoding buffer;

[0034] Dynamic bandwidth sampling module: based on the frame bursting technology, it calculates the upper limit of the network bandwidth and the background traffic in real time;

[0035] Network status discrimination module: outputs four levels of network status according to the data sending buffer usage rate and the sending rate;

[0036] Adaptive control module: performs encoding parameter adjustment and data filtering operations;

[0037] Dual-buffer architecture: includes an audio and video encoding buffer (doubly linked list) and a data sending buffer (fixed-capacity circular queue).

[0038] As a further solution of the present invention: the adaptive control module further includes:

[0039] Bitrate gradient adjustment unit: in the network alarm state, reduces the bitrate in 10% steps until the preset minimum threshold is reached;

[0040] Frame priority management unit: actively discards P frames when the bandwidth is insufficient, and dynamically adjusts the I frame generation frequency.

[0041] Compared with the prior art, the beneficial effects of the present invention are:

[0042] 1. The audio and video transmission method and system with adaptive network bandwidth realizes millisecond-level real-time bandwidth perception through the local dynamic bandwidth sampling technology (based on frame bursting measurement and background traffic modeling), completely getting rid of the dependence on the receiver feedback, and reducing the stuttering phenomenon caused by delay from the root cause; further combining the dual indicators of the data sending buffer usage rate and the sending rate to construct a multi-level network status discrimination mechanism, refining the network status into four levels and dynamically adjusting the strategy, significantly improving the congestion control response accuracy. In the network congestion scenario, by intelligently filtering non-critical frames (such as dynamically discarding P frames) and shortening the I frame interval, reducing redundant data transmission, and preferentially ensuring the coherence of key pictures and the continuity of the audio stream, it solves the problems of network burden and service quality decline caused by traditional full-volume transmission. Specific embodiments

[0043] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0044] Embodiment

[0045] The present invention provides the following technical solutions:

[0046] An audio - video transmission method adaptable to network bandwidth, comprising the following steps:

[0047] S1: Collect audio - video signals through an audio - video encoding component, generate encoded data based on preset encoding index parameters, and store it in the audio - video encoding cache;

[0048] S2: Extract audio - video frames from the audio - video encoding cache for protocol encapsulation, generate packetized data, and store it in the data sending cache;

[0049] S3: Monitor the current usage rate and sending rate of the data sending cache in real - time. Combining with the dynamic bandwidth sampling result, determine that the current network status is one of the following four levels: smooth network, bandwidth warning, insufficient bandwidth, extremely low bandwidth;

[0050] Select consecutive burst frames (such as key frame I - frames) in the video stream, record the reception timestamps of the first packet (rt1) and the last packet (rt n ) and calculate the instantaneous bandwidth upper limit:

[0051]

[0052] where P is the size of a single data packet (fixed at 1500 bytes), and n is the number of packets included in the burst frame.

[0053] S4: Dynamically adjust the encoding parameters and / or execute data filtering strategies according to the network status, including:

[0054] When the network status is a bandwidth warning, gradually reduce the encoding code rate and frame rate according to the gradient rule;

[0055] When the network status is insufficient bandwidth, discard the P - frames in the encoded data and shorten the I - frame interval;

[0056] When the network status is extremely low bandwidth, discard all video frames and only retain audio frames;

[0057] Based on the usage rate of the data sending cache and the sending rate (V), define four - level status and response strategies:

[0058]

[0059] S5: Send the adjusted packetized data to the receiving end through an adaptive transmission channel.

[0060] Specifically, the dynamic bandwidth sampling includes:

[0061] Based on the frame - level burst technology, calculate the current network bandwidth upper limit through the reception time difference between the first packet and the last packet and the frame size;

[0062] Combined with the network competition model, the average rate of background traffic is derived, and the formula is:

[0063]

[0064] Among them, C is the bandwidth upper limit, S is the sending rate, R is the receiving rate, and B is the average rate of background traffic.

[0065] Specifically, the network state determination specifically includes:

[0066] If the data sending buffer utilization rate ≤ 40% and the sending rate ≥ the preset threshold, it is determined that the network is smooth;

[0067] If the utilization rate is between 40% - 65% and the sending rate continues to decline, it is determined as a bandwidth warning;

[0068] If the utilization rate is between 65% - 85% and the sending rate is lower than 80% of the target code rate, it is determined as insufficient bandwidth;

[0069] If the utilization rate > 85% and the sending rate is lower than 50% of the target code rate, it is determined as extremely low bandwidth.

[0070] Specifically, the audio - video coding cache is a doubly - linked list structure. When the cache reaches the upper limit, the oldest I - frame interval data is discarded in chronological order, and new encoded data is appended to the end of the linked list.

[0071] Audio - video coding cache: Adopts a doubly - linked list structure, with a maximum cache duration of 5 seconds; when the cache is full, according to the "oldest I - frame interval discard" strategy (delete all data between the two earliest I - frames), to ensure that the latest data is transmitted first; Data sending cache: Fixed as a circular queue (capacity 10MB), and data is sent in FIFO order. When the utilization rate exceeds the threshold, the state discrimination is triggered.

[0072] Specifically, the data filtering strategy also includes:

[0073] In the extremely low network state, audio frames are preferentially retained and decoded synchronously based on the audio timestamp;

[0074] When the bandwidth recovers, the encoding code rate and I - frame interval are gradually restored according to the gradient rule.

[0075] An audio - video transmission system with adaptive network bandwidth includes:

[0076] Audio - video coding module: Used to collect and encode audio - video signals, and generate encoded data for storage in the audio - video coding cache;

[0077] Dynamic bandwidth sampling module: Based on the frame burst technology, it calculates the network bandwidth upper limit and background traffic in real - time;

[0078] Network status discrimination module: Outputs four-level network status according to the data sending buffer utilization rate and sending rate;

[0079] Adaptive control module: Performs encoding parameter adjustment and data filtering operations;

[0080] Dual-buffer architecture: Includes an audio-video encoding buffer (doubly linked list) and a data sending buffer (fixed-capacity circular queue).

[0081] Specifically, the adaptive control module further includes:

[0082] Bitrate gradient adjustment unit: In the network alarm state, reduces the bitrate in 10% steps until the preset minimum threshold is reached;

[0083] Frame priority management unit: Actively discards P frames when the bandwidth is insufficient and dynamically adjusts the I-frame generation frequency.

[0084] Although the embodiments of the present invention have been shown and described above, it can be understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those of ordinary skill in the art can make changes, modifications, substitutions, and variations to the above embodiments within the scope of the present invention.

Claims

1. An audio - video transmission method adaptive to network bandwidth, characterized in that, It includes the following steps: S1: Collect audio - video signals through an audio - video encoding component, generate encoded data based on preset encoding metric parameters, and store it in the audio - video encoding cache; S2: Extract audio - video frames from the audio - video encoding cache for protocol encapsulation, generate packetized data, and store it in the data sending cache; S3: Monitor the current utilization rate and sending rate of the data sending cache in real - time. Combining with the dynamic bandwidth sampling results, determine that the current network status is one of the following four levels: smooth network, bandwidth warning, insufficient bandwidth, extremely low bandwidth; S4: Dynamically adjust encoding parameters and / or execute data filtering strategies according to the network status, including: When the network status is a bandwidth warning, gradually reduce the encoding bitrate and frame rate according to the gradient rule; When the network status is insufficient bandwidth, discard P - frames in the encoded data and shorten the I - frame interval; When the network status is extremely low bandwidth, discard all video frames and only retain audio frames; S5: Send the adjusted packetized data to the receiving end through an adaptive transmission channel.

2. The method for audio and video transmission with adaptive network bandwidth according to claim 1, wherein The dynamic bandwidth sampling includes: Based on the frame - level burst technology, calculate the current network bandwidth upper limit through the reception time difference between the first packet and the last packet and the frame size; Combined with the network competition model, deduce the average background traffic rate, and the formula is: where C is the bandwidth upper limit, S is the sending rate, R is the receiving rate, and B is the average background traffic rate.

3. An audio and video transmission method with adaptive network bandwidth according to claim 1, characterized in that The specific network status determination includes: If the utilization rate of the data sending cache ≤ 40% and the sending rate ≥ the preset threshold, it is determined as a smooth network; If the utilization rate is between 40% - 65% and the sending rate continues to decline, it is determined as a bandwidth warning; If the utilization rate is between 65% - 85% and the sending rate is lower than 80% of the target bitrate, it is determined as insufficient bandwidth; If the utilization rate > 85% and the sending rate is lower than 50% of the target bitrate, it is determined as extremely low bandwidth.

4. An audio and video transmission method with adaptive network bandwidth according to claim 1, characterized in that: The audio - video encoding cache is a doubly - linked list structure. When the cache reaches the upper limit, discard the oldest I - frame interval data in chronological order and append new encoded data to the end of the linked list.

5. An audio and video transmission method and system with adaptive network bandwidth according to claim 1, characterized in that The data filtering strategy further includes: In the extremely low network state, preferentially retain audio frames and synchronize decoding based on the audio timestamp; When the bandwidth recovers, gradually restore the encoding bitrate and I - frame interval according to the gradient rule.

6. An audio and video transmission system with adaptive network bandwidth, characterized in that, It includes: Audio - video encoding module: Used to collect and encode audio - video signals, generate encoded data and store it in the audio - video encoding cache; Dynamic bandwidth sampling module: Based on the frame burst technology, calculate the network bandwidth upper limit and background traffic in real - time; Network status discrimination module: Output four - level network status according to the utilization rate and sending rate of the data sending cache; Adaptive control module: Execute encoding parameter adjustment and data filtering operations; Dual - cache architecture: Includes an audio - video encoding cache (doubly - linked list) and a data sending cache (fixed - capacity circular queue).

7. An audio and video transmission system with adaptive network bandwidth according to claim 6, characterized in that The adaptive control module further includes: Bitrate gradient adjustment unit: In the network warning state, reduce the bitrate by 10% steps until reaching the preset minimum threshold; Frame priority management unit: Actively discard P - frames when the bandwidth is insufficient and dynamically adjust the I - frame generation frequency.

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