CN117749317A - A fountain code encoding and decoding method and device - Google Patents

Abstract

The embodiment of the application provides a fountain code encoding and decoding method and device, wherein an encoding device can acquire a data packet loss rate; adjusting the weight value of the coding frame in the image group according to the data packet loss rate; fountain coding is carried out according to the weight value of the coding frame, and a coding data packet is obtained; the encoded data packet is transmitted to a decoding device. By the method, the fountain code coding efficiency can be improved, and the requirements of video application scenes are more adapted.

Description

A fountain code encoding and decoding method and device

Technical field

The embodiments of the present application relate to the field of encoding and decoding technology, and in particular to a fountain code encoding and decoding method and device.

Background technique

In the existing technology, there are many channel coding schemes, such as error control coding (forward error correction coding, etc.). This method usually requires feedback retransmission and fixed coding rate, so it is difficult to ensure reliable transmission of information. Therefore, it is very urgent to find channel coding technology suitable for different channel states. Among them, fountain code, as a channel code, has the advantages of low coding complexity, low overhead, and high channel capacity. However, current research on fountain codes mostly focuses on how to design degree distribution to achieve the purpose of optimizing coding and decoding efficiency. However, the existing technology does not consider how fountain codes can be combined with actual business scenarios to take advantage of them.

Contents of the invention

This application provides a fountain code encoding and decoding method and device to adapt to the needs of actual business scenarios.

In a first aspect, the present application provides a fountain code encoding method, which can be executed by a fountain code encoding device, where the fountain code encoding device can be an image encoder, a central processing unit (CPU), or a graphics processor. (graphics processing unit, GPU), etc., this application is not specifically limited here.

The fountain code encoding device obtains the data packet loss rate; adjusts the weight value of the encoded frame in the image group according to the data packet loss rate, performs fountain encoding according to the weight value of the encoded frame, and obtains the encoded data packet; transmits the encoded data packet to the decoding device.

In this application, the fountain code encoding device adjusts the weight value of the encoded frame according to the data packet loss rate, and then performs fountain encoding based on the degree distribution, which can adapt to the scene requirements of streaming media and ensure the coding efficiency of streaming media data.

In an optional manner, the data packet loss rate is indicated by one of the following parameters:

The ratio of the encoded data packets that the decoding device failed to parse within the preset time period to all the encoded data packets received;

The difference between the first ratio and the second ratio. The first ratio is the ratio of the coded data packets that the decoding device failed to parse in the first time period to all the coded data packets received; the second ratio is the ratio of the coded data packets that the decoding device failed to parse in the second time period. The ratio of the coded data packets that were not successfully parsed within the segment to all the coded data packets received; where the first time period and the second time period are adjacent time periods.

This method makes it easier to obtain the data packet loss rate.

In an optional method, adjusting the weight value of the encoded frame in the image group according to the data packet loss rate includes: adjusting the weight value of the encoded frame in the image group according to the data packet loss rate within a preset time period.

This method can improve the transmission success rate of key frames, improve coding efficiency, and ensure coding quality.

In an optional manner, the encoded frame includes at least one of the following: I frame, P frame and B frame; the priority of I frame, P frame and B frame decreases in order; the image is adjusted according to the data packet loss rate The weight value of the coded frames in the group, including:

Within the preset time period, when the data packet loss rate is greater than the packet loss threshold, the weight values of the encoded frames in the image group are adjusted in order of priority. Among them, the sum of the weight values of the encoded frames is the preset value, and the higher priority The weight value of the coded frame is greater than the weight value of the coded frame with lower priority.

This method can improve the transmission success rate of key frames, improve coding efficiency, and ensure coding quality.

In an optional method, when the packet loss rate is greater than the packet loss threshold, the weight values of the encoded frames in the image group are adjusted sequentially in order of priority, which also includes:

Obtain the first data packet loss rate in the i-th preset time period, i is a positive integer;

When the first data packet loss rate is greater than the packet loss threshold, adjust the weight value of the encoded frame according to the first strategy, and the first strategy includes increasing the weight value of the encoded frame of the first priority;

Obtain the second data packet loss rate within the i+1 preset time period;

When the second data packet loss rate is less than the first data packet loss rate, adjust the weight value of the encoded frame in the i+2 preset time period according to the first strategy; or, the second data packet loss rate is not less than the first data packet loss rate. When the packet loss rate is determined, adjust the weight value of the encoded frame in the i+2 preset time period according to the second strategy. The second strategy includes reducing the weight value of the encoded frame of the first priority;

Obtain the third data packet loss rate within the i+2 preset time period;

When the third data packet loss rate is less than the second data packet loss rate, the weight value of the encoded frame in the i+3 preset time period is adjusted according to the second strategy, or the third data packet loss rate is not less than the second data packet loss rate. When the packet loss rate is reduced, the weight value of the encoded frame in the i+3 preset time period is adjusted according to the third strategy. The third strategy includes increasing the weight value of the encoded frame of the second priority.

This method can improve the transmission success rate of key frames, improve coding efficiency, and ensure coding quality.

In an optional method, adjusting the weight value of the encoded frame in the image group according to the data packet loss rate also includes: if the data packet loss rate in any preset time period is less than the packet loss threshold, the encoded frame will not be adjusted. weight value.

In an optional approach, the default value is 1.

In an optional method, the weight value of the encoded frame in the image group is adjusted according to the data packet loss rate, including:

The data packet loss rate is input into the weight adjustment model and one or more of the following algorithms are used to determine the weight value of the encoded frame in the image group: Monte Carlo algorithm, back propagation algorithm, Newton gradient method, one-dimensional search algorithm .

In this way, the key frame coding efficiency can be adjusted in time and the decoding success rate can be improved.

In an optional method, the encoded data packet includes: the position of the encoded frame and the degree value of the fountain encoding.

In a second aspect, the present application provides a fountain code decoding method, which can be executed by a fountain code decoding device, where the fountain code decoding device can be an image decoder, which is not specifically limited in this application.

The fountain code decoding device receives the encoded data packet; the encoded data packet is determined by fountain coding according to the weight value of the encoded frame; it analyzes the encoded data packet to obtain video data.

In an optional manner, determine the data packet loss rate;

Feed back the data packet loss rate to the encoding device.

In an optional manner, the data packet loss rate is indicated by one of the following parameters:

The ratio of the encoded data packets that the decoding device failed to parse within the preset time period to all the encoded data packets received;

The difference between the first ratio and the second ratio. The first ratio is the ratio of the coded data packets that the decoding device failed to parse in the first time period to all the coded data packets received; the second ratio is the ratio of the coded data packets that the decoding device failed to parse in the second time period. The ratio of the coded data packets that were not successfully parsed within the segment to all the coded data packets received; where the first time period and the second time period are adjacent time periods.

In a third aspect, the present application provides a fountain code encoding device, including: a transceiver unit and a processing unit; the transceiver unit is used to obtain the data packet loss rate; the processing unit is used to adjust the coding frame in the image group according to the data packet loss rate. Weight value, perform fountain encoding according to the weight value of the encoded frame, and obtain the encoded data packet; transmit the encoded data packet to the decoding device.

In an optional manner, the data packet loss rate is indicated by one of the following parameters:

The ratio of the encoded data packets that the decoding device failed to parse within the preset time period to all the encoded data packets received;

The difference between the first ratio and the second ratio. The first ratio is the ratio of the coded data packets that the decoding device failed to parse in the first time period to all the coded data packets received; the second ratio is the ratio of the coded data packets that the decoding device failed to parse in the second time period. The ratio of the coded data packets that were not successfully parsed within the segment to all the coded data packets received; where the first time period and the second time period are adjacent time periods.

In an optional manner, the processing unit is specifically configured to: adjust the weight value of the encoded frame in the image group according to the data packet loss rate within a preset time period.

In an optional manner, the encoded frame includes at least one of the following: I frame, P frame and B frame; the priority of I frame, P frame and B frame decreases in order; a processing unit is specifically used for:

Within the preset time period, when the data packet loss rate is greater than the packet loss threshold, the weight values of the encoded frames in the image group are adjusted in order of priority. Among them, the sum of the weight values of the encoded frames is the preset value, and the higher priority The weight value of the coded frame is greater than the weight value of the coded frame with lower priority.

In an optional manner, the processing unit is also used to:

Obtain the first data packet loss rate in the i-th preset time period, i is a positive integer;

When the first data packet loss rate is greater than the packet loss threshold, adjust the weight value of the encoded frame according to the first strategy, and the first strategy includes increasing the weight value of the encoded frame of the first priority;

Obtain the second data packet loss rate within the i+1 preset time period;

When the second data packet loss rate is less than the first data packet loss rate, adjust the weight value of the encoded frame in the i+2 preset time period according to the first strategy; or, the second data packet loss rate is not less than the first data packet loss rate. When the packet loss rate is determined, adjust the weight value of the encoded frame in the i+2 preset time period according to the second strategy. The second strategy includes reducing the weight value of the encoded frame of the first priority;

Obtain the third data packet loss rate within the i+2 preset time period;

When the third data packet loss rate is less than the second data packet loss rate, the weight value of the encoded frame in the i+3 preset time period is adjusted according to the second strategy, or the third data packet loss rate is not less than the second data packet loss rate. When the packet loss rate is reduced, the weight value of the encoded frame in the i+3 preset time period is adjusted according to the third strategy. The third strategy includes increasing the weight value of the encoded frame of the second priority.

In an optional method, the processing unit is also configured to: if the data packet loss rate in any preset time period is less than the packet loss threshold, not adjust the weight value of the encoded frame.

In an optional approach, the default value is 1.

In an optional manner, the processing unit is specifically used to:

The data packet loss rate is input into the weight adjustment model and one or more of the following algorithms are used to determine the weight value of the encoded frame in the image group: Monte Carlo algorithm, back propagation algorithm, Newton gradient method, one-dimensional search algorithm .

In an optional method, the encoded data packet includes: the position of the encoded frame and the degree value of the fountain encoding.

In the fourth aspect, this application provides a fountain code decoding device, including: a processing unit and a transceiver unit;

The transceiver unit is used to receive the encoded data packet; the encoded data packet is determined by fountain coding according to the weight value of the encoded frame; the processing unit is used to parse the encoded data packet to obtain video data.

In an optional method, the processing unit is used to determine the data packet loss rate; the transceiver unit is used to feed back the data packet loss rate to the encoding device.

In an optional manner, the data packet loss rate is indicated by one of the following parameters:

The ratio of the encoded data packets that the decoding device failed to parse within the preset time period to all the encoded data packets received;

The difference between the first ratio and the second ratio. The first ratio is the ratio of the coded data packets that the decoding device failed to parse in the first time period to all the coded data packets received; the second ratio is the ratio of the coded data packets that the decoding device failed to parse in the second time period. The ratio of the coded data packets that were not successfully parsed within the segment to all the coded data packets received; where the first time period and the second time period are adjacent time periods.

In a fifth aspect, embodiments of the present application provide a fountain code encoding device including: a mutually coupled non-volatile memory and a processor, the processor calls the program code stored in the memory to execute the first aspect or the second aspect. One aspect of either design is the method described.

In a sixth aspect, embodiments of the present application provide a fountain code decoding device including: a mutually coupled non-volatile memory and a processor, and the processor calls the program code stored in the memory to execute the second aspect or the third aspect. Either design method described in the two aspects. It should be noted that the processor does not perform encoding operations.

In a seventh aspect, embodiments of the present application provide a fountain code processing system, including the fountain code encoding device described in the fifth aspect and the fountain code decoding device described in the sixth aspect.

In an eighth aspect, embodiments of the present application provide a computer-readable storage medium that stores program code, wherein the program code includes any one of the methods for executing the first aspect or the second aspect. Instructions for some or all of the steps of a method.

In a ninth aspect, embodiments of the present application provide a computer program product, which when the computer program product is run on a computer, causes the computer to execute part or all of the steps of any method of the first aspect or the second aspect.

It should be understood that the beneficial effects of the second to ninth aspects of the present application can be referred to the relevant description of the first aspect, and will not be described again.

Description of drawings

Figure 1 shows a schematic diagram of LT code encoding and decoding;

Figure 2 shows a schematic diagram of Raptor code encoding;

Figure 3 shows a schematic structural diagram of an image group;

Figure 4 shows a schematic diagram of a streaming media data processing flow provided by an embodiment of the present application;

Figure 5 shows a schematic flow chart of a fountain code encoding and decoding method provided by an embodiment of the present application;

Figure 6 shows a schematic diagram of a sliding window provided by an embodiment of the present application;

Figure 7 shows a schematic diagram of a weight adjustment model provided by an embodiment of the present application;

Figure 8 shows a schematic structural diagram of a fountain code processing device provided by an embodiment of the present application;

Figure 9 shows a schematic structural diagram of a fountain code processing device provided by an embodiment of the present application;

Figure 10 shows a schematic structural diagram of a fountain code processing device provided by an embodiment of the present application.

Detailed ways

In order to make the purpose, technical solutions and advantages of the present application clearer, the present application will be described in further detail below in conjunction with the accompanying drawings. The specific operation methods in the method embodiments can also be applied to the device embodiments or system embodiments. Among them, in the description of this application, unless otherwise stated, the meaning of "plurality" is two or more. Therefore, the implementation of the device and the method can be referred to each other, and repeated descriptions will not be repeated.

In order to better explain the solution of this application, first, the technical terms that may be involved in this application are explained, as follows:

1. Existing fountain codes include two types: luby transform codes (LT codes) and rapid tornado codes (Raptor codes). LT code is the first specific implementation of fountain code, which was proposed by Michael Luby. Later, Amin Shokrollahi improved the LT code and proposed the second type of fountain code, namely Raptor code.

1), LT code

Among them, the encoding process of LT code can be shown in (a) in Figure 1. The data to be encoded is divided into multiple bit data packets S ₁ , S ₂ ...Sn of equal length, and each coded packet C ₁ , C ₂ ...Cn randomly generates a degree value d. The degree value is the number of data packets related to it. For example, the C1 degree is 3 and the C2 degree is 1. Among all data packets, d data packets are randomly selected evenly and encoded. The packet is the calculation result of the XOR of d input data packets.

The receiving end must know the degree value of each encoded packet when decoding, and which data packets are specifically XORed. If at a certain moment, all packets with degree 1 disappear, but there are still some source data packets that have not been recovered, the decoding will fail. Too many packets with a degree of 1 will also lead to redundancy and low efficiency. As shown in (b) in Figure 1, find the encoding packet with degree 1, because it is only related to one data packet. If there is no encoding packet with degree 1, the decoding process ends. Perform an XOR calculation on the recovered data packet with all other encoding packets related to this data packet, and reduce the degree of these encoding packets by 1. This process may generate new encoding packets with a degree of 1 (exclusive OR operation ). Repeat the above steps until all are translated. As shown in (b) in Figure 1, S ₂ is a coded packet with degree 1. Data packet C ₂ can be obtained, and then the XOR operation is performed to recover all the data packets.

In addition, ideally, a degree distribution will only generate one coded packet with degree 1, and every time a data packet is recovered, it can regenerate exactly one coded packet with degree 1. This goes back and forth, always keeping a coded packet with degree 1 available, until all n data packets are decoded, and the decoding process ends. Luby proposed the ideal solitary wave distribution (later, in order to enhance the robustness, the robust solitary wave distribution was proposed), but the form of the degree distribution is not specified here.

2), Raptor code

Raptor code mainly consists of two encoding processes: precoding and LT encoding. As shown in Figure 2, the data packets S ₁ , S ₂ ...S ₆ to be encoded are precoded to obtain precoded coded packets C ₁ , C ₂ ...C ₉ , in which the number of precoded coded packets is greater than the data packets to be coded. C ₇ , C ₈ , and C ₉ are redundant nodes. Then, XOR operation is performed on the precoding encoding packets C ₁ , C ₂ ...C ₉ to determine the encoding data.

Process 1. Precoding is mainly a traditional erasure code with a fixed code rate. The calculation speed is very fast. It is commonly composed of a high-density parity check code and a simple regular low-density parity check code cascaded (such as Hamming code + low density check code).

Process 2. The LT encoding process becomes the intermediate encoding block of the precoding output, and the process follows the standard LT encoding process.

2. Streaming media

Streaming media is a technology that compresses continuous multimedia data (video, images, audio, etc.) and transmits it in segments through the network. The client can directly play the data after receiving a portion of the continuous data.

Taking the H.265 video coding protocol as an example, the block coding decision of the existing coding protocol adopts the traversal mode. For example, the Lagrangian optimization method is used to determine all coding parameters for each LCU, which mainly includes the CU division mode, PU and TU in the CU. division, PU prediction mode, etc. Afterwards, the encoding process is performed according to the CU. First, the original pixel data (original pixel) of the CU is predicted. The prediction is divided into intra prediction (intra prediction) and inter prediction (interprediction). When encoding sources, encoding is usually performed based on a group of pictures (GoP). A group of pictures may include one or more encoded frames, such as I frames, P frames, and B frames, where, The I frame is a key frame, and subsequent P frames or B frames refer to the I frame for coding processing. Figure 3 shows a schematic structural diagram of an image group. The corresponding time interval of the image group is 30S. The structure of the encoded frame is IIPP...B. The shadow filling represents I frame, the non-shading filling represents P frame, and the black filling represents B. frame.

In this application, "and/or" describes the relationship between associated objects, indicating that there can be three relationships, for example, A and/or B, which can mean: A exists alone, A and B exist simultaneously, and B exists alone. , where A and B can be singular or plural. And, unless otherwise stated, the ordinal numbers such as "first" and "second" mentioned in the embodiments of this application are used to distinguish multiple objects, and are not used to limit the order, timing, priority or priority of multiple objects. Importance.

Reference in this specification to "one embodiment" or "some embodiments" or the like means that a particular feature, structure or characteristic described in connection with the embodiment is included in one or more embodiments of the application. Therefore, the phrases "in one embodiment", "in some embodiments", "in other embodiments", "in other embodiments", etc. appearing in different places in this specification are not necessarily References are made to the same embodiment, but rather to "one or more but not all embodiments" unless specifically stated otherwise. The terms “including,” “includes,” “having,” and variations thereof all mean “including but not limited to,” unless otherwise specifically emphasized.

There are already some conceptual designs of unequal error protection fountain codes, but they only exist in academic research and there is no commercial technology. The unequal error protection fountain code achieves the distinction of information importance by giving different participation coding weights to information data and dividing different information into multiple importance levels. When the inventor was studying the fountain code, he found that applying the encoding scheme of the fountain code to streaming media is beneficial to better encoding and transmission of streaming media data. The application process can be shown in Figure 4. Image data (GRB data or YUV data) is encoded by H.26X (X=3/4/5), then reshaped (such as divided into multiple sliding windows), encoded by fountain code, and packaged and sent to the client. In addition to being used in streaming media, the encoding scheme using fountain codes can also be used for the transmission of omnidirectional video, augmented reality (AR)/virtual reality (VR) and other media data. This application is in This is not specifically limited.

In some streaming media scenarios, some data are important information and require more protection. For example, in MPEG streams, if the I frame is designed independently of other frames, P depends on the I information, and B depends on the previous I and P information, so the I frame requires more Protection, how to perform targeted adaptation of fountain codes based on streaming media frames is very important. In addition, the artificially set weights are relatively mechanical. When certain scenes have transmission failures (blurred screens) or quality degradation (mosaic), frame weights cannot be adjusted adaptively.

The current main fountain code technology has the disadvantage that it cannot perform weight adjustment or blind weight adjustment according to the scene. Especially in some streaming media scenarios, some data are important information and require more protection. Although the existing unequal error protection fountain code technology takes into account the difference in importance of information, it does not adjust the probability or weight of the coded frame in the image group to be selected by the coded bit to distinguish the importance and then perform fountain code coding, which cannot be practical. Guaranteed transmission protection of key coded frames. In addition, there is also a certain degree of mechanics in how to carry out targeted adaptation, and it is often accomplished by artificial settings. For example, the unequal error protection encoding mentioned by the academic circle (no practical application case) has certain artificial setting problems. , cannot be adjusted for scene adaptation.

Based on this, this application provides a fountain code encoding method to better adapt to the scene requirements of streaming media. It can be executed with reference to Figure 5, where the encoding device can be understood as an encoder, CPU, GPU, etc., and the decoding device can Understood as a decoder, etc., the execution is as follows:

Step 501: The encoding device obtains the data packet loss rate.

When the fountain code encoding solution is first implemented, the data packet loss rate may be a preset value. Optionally, the data packet loss rate can be delivered through other data processing devices, such as servers, etc., or it can also come from the decoding device, that is, delivered through the decoding device. In Figure 5, the decoding device passes step 500 to send data. The packet loss rate is taken as an example.

Among them, the data packet loss rate can be indicated by one of the following parameters:

Parameter 1. The ratio of the coded data packets that the decoding device failed to parse successfully within the preset time period to all the coded data packets received.

For example, if the preset time period is 10S, the decoding device receives 10 encoded data packets within 10S, successfully parses 8 encoded data packets, and fails to parse 2 (10-8) encoded data packets, then the data packet loss rate can be It is 2/10. This is only an exemplary description. The specific preset time period can be set according to the actual application and is not specifically limited in this application.

Parameter 2, the difference between the first ratio and the second ratio. The first ratio is the ratio of the encoded data packets that the decoding device failed to parse in the first time period to all the encoded data packets received; the second ratio is the ratio of the decoding device in the first time period. The ratio of coded data packets that were not successfully parsed to all coded data packets received in the second time period; where the first time period and the second time period are adjacent time periods.

For example, the first time period is 8:00~8:10, the second time period is 8:10~8:20, the number of successfully parsed encoded data packets in the first time period is 6, and the number of unsuccessfully parsed encoded data packets is is 4, the number of received data packets is 10, the first ratio is 4/10, the number of successfully parsed encoded data packets in the second time period is 18, the number of unsuccessfully parsed encoded data packets is 2, and the number of received data packets is 20, the second ratio is 2/20, and the difference between the first ratio and the second ratio is 0.3 (4/10-2/20).

Of course, in practical applications, the decoding device can feed back parameter 1 or parameter 2, or even perform a weighted operation on parameter 1 and parameter 2 and then feed them back to the encoding device. This application is not specifically limited here, as long as the encoding device is based on decoding The parameters fed back by the device can be used to obtain information on the data packet loss rate.

Step 502: The encoding device adjusts the weight value of the encoded frame in the image group according to the data packet loss rate.

Among them, the weight value of the encoded frame in the image group is not always unchanged. It can be adjusted based on the data packet loss rate within the preset time period. For example, within the preset time period 1, the data packet loss rate increases, which can improve the encoding The weight value of the frame can reduce the data packet loss rate, which can reduce the weight value of the encoded frame. The specific adjustment can be flexibly set based on the size of the data packet loss rate. Compared with the mechanical setting of the weight value and the fixed weight value, this application Adjusting the weight value of the encoded frame based on the data packet loss rate can improve encoding efficiency.

For example, the encoded frames of a GoP may include I frames, P frames, and B frames, and one video data may correspond to multiple GoPs. The time length of each GoP is the same, and the format of the encoded frames in each GoP is the same. , for example, video data 1 includes 3 GoPs, the time length of each GoP is 10S, and the format of the corresponding encoded frame is IBBPBBPBBPBB, the weight value corresponding to the I frame, that is, the probability of selection by the encoding device, can be weight 1, P frame The corresponding weight value, that is, the probability of selection by the encoding device, can be weight 2. The weight value corresponding to the B frame, that is, the probability of selection by the encoding device, can be weight 3. Weight 1 can be greater than weight 2, and weight 2 can be greater than weight 3. This application is This is not specifically limited.

Optionally, the encoding device divides the GoP into N sliding windows of equal length; the sliding windows overlap; N≥1; N is a positive integer. Adjust the weight value of each encoded frame in the sliding window according to the data packet loss rate. Video data has multiple GoPs. Generally speaking, an independent video has a fixed GoP format and consists of one I frame and multiple P or B frames (I/P/B, I/B or I/P). . For example, a GoP can be composed of 1 I frame, 3 P frames, and 8 B frames. The corresponding encoding frame format is IBBPBBPBBPBB. The encoding device can divide a GOP into multiple sliding windows, and an I frame can be segmented. to multiple sliding windows. For example, after allocating GoP I frames to sliding windows 1, 2, and 3, if there are still I frames left, the remaining parts can be allocated to the next sliding window 4, and the B frames can be divided. When reaching sliding windows 4, 5, 6, etc., if there are still B frames left, the remaining parts can be allocated to the next sliding window. Since the size of the encoding frame is variable, the number of sliding windows it occupies also varies. The segmented window is type-marked according to the actual size-dominated frame. For example, the encoding frames in sliding window 1 are all from I frames, and their type is marked I. Frame, the encoded frame of sliding window 4 comes from the remaining part of the I frame and the B frame part. The type is marked according to the actual occupancy proportion. If the I frame proportion is not less than 0.5, the sliding window 4 type can be marked as I frame. Otherwise, it is marked as B frame. By analogy, define the frame types of different sliding windows. After that, the weight values of different types of coded frames within the preset time can be adjusted according to the data packet loss rate. For example, if the weight value of the I frame is adjusted to increase, the probability of being selected for any sliding window defined as an I frame increases, then the I frame is selected. Better chance of protection.

As shown in Figure 6, GoP can be 1 I frame, 3 P frames, and 8 B frames. The format of the corresponding encoded frame is IBBPBBPBBPBB, where sliding window 1 to sliding window 3 are all I frames, and sliding window 4 Corresponding to some I frames and B frames, one GOP can correspond to multiple sliding windows. Here, only four sliding windows are used as an example. The weight value of the encoded frame in the sliding window can be adjusted based on the data packet loss rate. Among them, the weight value of each coding frame in different sliding windows is determined. Based on the determined weight value, focused fountain code encoding can ensure the coding reliability of the coding frame. In addition, sliding window 1 can correspond to data A, sliding window 2 can correspond to data B, sliding window 3 can correspond to data C, and sliding window 4 can correspond to data D. Afterwards, fountain code encoding can be performed based on the degree distribution. The specific degree distribution will not be discussed here. The limitation can be understood by referring to the existing degree distribution method, and will not be described in detail here.

In this application, the priorities of I frames, P frames, and B frames decrease in order; within the preset time period, when the data packet loss rate is greater than the packet loss threshold (indicating that the current encoding strategy cannot meet the application requirements of actual scenarios), Adjust the weight values of the encoded frames in sequence according to the priority order, where the sum of the weight values of the encoded frames is the default value (usually the default value is 1, but in actual applications, it can also be adjusted according to needs, such as setting The default value is 2, etc., which is not specifically limited in this application), and the weight value of a coded frame with a high priority is greater than the weight value of a coded frame with a low priority.

For example, the GoP in Figure 6 above includes I frames, P frames and B frames. Among them, the I frame has the highest priority and the B frame has the lowest priority. When setting the weight of the encoded frame, the weight value of the I frame can be Set to weight 1, the weight value of P frame is set to weight 2, and the weight value of B frame is set to weight 3. In a possible implementation, the following relationship may exist between weight 1, weight 2, and weight 3: weight 1 is greater than weight 2, greater than weight 3, and weight 1+2*weight 2+6*weight 3 is equal to the preset value.

Specifically, when the data packet loss rate is greater than the packet loss threshold, the weight values of the encoded frames are adjusted in order of priority, where the format of the encoded frames in each preset time period is the same, and also includes:

Obtain the first data packet loss rate in the i-th preset time period; i is a positive integer; when the first data packet loss rate is greater than the packet loss threshold, adjust the i+1-th preset time period according to the first strategy The weight value of the encoded frame. The first strategy includes increasing the weight value of the encoded frame of the first priority; obtaining the second data packet loss rate within the i+1 preset time period; the second data packet loss rate is less than the first When the data packet loss rate is high, it means that the direction of adjusting the weight value of the encoded frame according to the first strategy is correct, so continue to adjust the weight value of the encoded frame in the i+2th preset time period according to the first strategy; or, the second data loss When the packet rate is not less than the first data packet loss rate, it means that the direction of adjusting the weight value of the encoded frame according to the first strategy is wrong. Therefore, the weight value of the encoded frame in the i+2 preset time period is adjusted according to the second strategy. The second strategy includes reducing the weight value of the first priority encoded frame; obtaining the third data packet loss rate within the i+3 preset time period; when the third data packet loss rate is less than the second data packet loss rate, indicate The direction of adjusting the weight value of the encoded frame according to the second strategy is correct, so continue to adjust the weight value of the encoded frame in the i+3 preset time period according to the second strategy; or, the third data packet loss rate is not less than the second data When the packet loss rate is high, it means that the direction of adjusting the weight value of the encoded frame according to the second strategy is wrong. Therefore, the weight value of the encoded frame of the i+3 sliding window is adjusted according to the third strategy. The third strategy includes increasing the second priority. The weight value of the encoded frame.

For example, the encoding device determines 7 preset time periods. The format of the encoded frames in each preset time period includes I frame, P frame and B frame. The packet loss threshold is Y. The data packet loss rate in the preset time period 1 is greater than Y, then increase the weight value of the I frame in the preset time period 2 (for example, increase 0.1), and accordingly reduce the weight value of the P frame or the weight value of the B frame in the preset time period 2, or the weight value of the P frame And the weight value of the B frame is reduced, or only the weight value of the B frame is reduced and the weight value of the P frame remains unchanged. This is only an illustrative explanation and is not specifically limited to ensure that the weight value of the I frame and the P frame are The weight value of and the weight value of the B frame are added to the default value of 1. Obtain the data packet loss rate of preset time period 2. If the data packet loss rate decreases, it is determined that the strategy for adjusting the weight value is correct. Adjust the strategy according to the same weight in preset time period 3 to preset time period 7. Adjust the weight, but if the packet loss rate in any preset time period from preset time period 3 to preset time period 7 (assuming that the preset time period is preset time period 5) is less than or equal to Y, exit the weight Adjust the strategy (that is, do not adjust the weight value of the coded frame), maintain the weight adjustment strategy of the preset time period 5, adjust the weight value of the coded frame in the preset time period 6 and the preset time period 7, and perform fountain code encoding processing.

On the contrary, if the weight value of the I frame in the preset time period 2 is increased, and the weight value of the B frame in the preset time period 2 is correspondingly reduced, the data packet loss rate in the preset time period 2 does not decrease, but increases, so as The opposite strategy adjusts the weight value of the encoded frame in the preset time period 3, reduces the weight value of the I frame in the preset time period 3 (for example, by 0.1), and accordingly increases the weight value of the B frame in the preset time period 3, so as to It is guaranteed that the weight value of the I frame, the weight value of the P frame and the weight value of the B frame add up to the preset value 1. Obtain the data packet loss rate in the preset time period 3. If the data packet loss rate in the preset time period 3 decreases, it is determined that the adjustment strategy of reducing the weight value of the I frame is correct.

If the change in data packet loss rate is not obvious no matter whether you increase the weight value of I frame in preset time period 3 or decrease the weight value of I frame in preset time period 3, then adjust the weight value of P frame to increase P The weight value of the frame (such as increasing 0.05), correspondingly reduce the weight value of the I frame or the weight value of the B frame to ensure that the weight value of the I frame, the weight value of the P frame and the weight value of the B frame add up to the preset value 1. Obtain the data packet loss rate in the preset time period 4. If the data packet loss rate decreases, it is determined that the strategy for adjusting the weight value is correct. Adjust the strategy according to the same weight in the preset time period 5 to 7. The weight is adjusted, but if the packet loss rate in any subsequent preset time period is less than or equal to Y, the weight adjustment strategy will be exited, the weight value of the last adjusted encoding frame will be maintained, and the fountain code encoding process will be performed.

To sum up, in a fountain code encoding embodiment provided by this application, you can first try to increase the weight value of the I frame within the preset time period to see whether the packet loss rate changes in a better direction; if so, continue to increase the subsequent The weight value of I frames in the preset time period until the packet loss rate meets the requirements; otherwise, reduce the weight value of I frames in the sliding window to see if the packet loss rate changes in a better direction. If increasing or decreasing the weight value of I frames cannot significantly change the packet loss rate, try adjusting the weight values of P frames and B frames.

Optionally, the encoding device can also input the data packet loss rate into a weight adjustment model (wherein, the weight adjustment model can be a machine learning model, a deep learning model, or other models (this application is not specifically limited here)), Determine the weight value of the coded frame in the image group using one or more of the following algorithms: Monte Carlo algorithm, backpropagation algorithm, Newton gradient method, one-dimensional search algorithm. The details can be as follows:

(1) First, establish a weight adjustment model for I/P/B frame weight and data packet loss rate. Specifically, a deep neural network can be defined. The input is the current bandwidth and signal strength sequence, and the output is I frame and P frame. and B frame weight values. The neural network selects appropriate I frame, P frame, and B frame weight values based on the current bandwidth and signal strength changes. The optimization of parameters needs to be evaluated through the objective function, as shown in Figure 7.

(2) Establish an objective function to serve as a measure of parameter optimization, and use the data packet loss rate as the objective function to perform a minimum optimization solution. The least squares method can be used to find the optimal solution.

(3) Use optimization methods (BP, Newton gradient, etc.) to achieve approximation to the minimum data packet loss rate, thereby obtaining appropriate weight distribution of I frames, P frames, and B frames.

Step 503: The encoding device performs fountain encoding according to the weight value of the encoded frame to obtain the encoded data packet.

Specifically, after the encoding device determines the weight value of the encoding frame, it can perform data shaping. When performing fountain encoding, the weight value of the encoding frame can be used to adjust the degree value distribution of the fountain encoding, according to the above-mentioned LT code or Raptor code encoding method. Do fountain coding.

For example, the coded frames include I frames, P frames and B frames. Among them, the weight value of the I frame is weight 1, the weight value of the P frame is weight 2, and the weight value of the B frame is weight 3. After data shaping, the LT code is used When encoding fountains, the degree value can be understood by referring to the existing degree distribution method, which will not be described again here.

Step 504: The encoding device transmits the encoded data packet to the decoding device.

Among them, the encoded data packet includes: the position of the encoded frame and the degree value of the fountain encoding, so that the decoding device can successfully parse the encoded data packet.

Step 505: The decoding device analyzes the encoded data packet to obtain video data.

Encoding and decoding fountain codes in this way can better apply fountain codes to streaming media, ensure the efficiency of data encoding and decoding in streaming media, and at the same time provide users with a good business experience.

The above mainly introduces the solutions provided by the embodiments of the present application from the perspective of device interaction. It can be understood that, in order to implement the above functions, each device may include a corresponding hardware structure and/or software module to perform each function. Those skilled in the art should easily realize that, with the units and algorithm steps of each example described in conjunction with the embodiments disclosed herein, the embodiments of the present application can be implemented in the form of hardware or a combination of hardware and computer software. Whether a function is performed by hardware or computer software driving the hardware depends on the specific application and design constraints of the technical solution. Skilled artisans may implement the described functionality using different methods for each specific application, but such implementations should not be considered beyond the scope of this application.

Embodiments of the present application can divide the device into functional units according to the above method examples. For example, each functional unit can be divided corresponding to each function, or two or more functions can be integrated into one unit. The above integrated units can be implemented in the form of hardware or software functional units.

In the case of using an integrated unit, FIG. 8 shows a possible exemplary block diagram of the fountain code processing device involved in the embodiment of the present application. As shown in FIG. 8 , the fountain code processing device 800 may include: a processing unit 801 and a transceiver unit 802 . The processing unit 801 is used to control and manage the actions of the fountain code processing device 800. The transceiver unit 802 is used to support communication between the fountain code processing device 800 and other devices. Optionally, the transceiver unit 802 may include a receiving unit and/or a sending unit, respectively configured to perform receiving and sending operations. Optionally, the fountain code processing device 800 may also include a storage unit for storing program codes and/or data of the fountain code processing device 800 . The transceiver unit may be called an input-output unit, a communication unit, etc., the transceiver unit may be a transceiver, and the processing unit may be a processor. When the image processing device is a module (such as a chip) in a communication device, the transceiver unit may be an input-output interface, an input-output circuit, or an input-output pin, etc., and may also be called an interface, a communication interface, or an interface circuit, etc.; The processing unit may be a processor, a processing circuit or a logic circuit, etc. Specifically, the image processing device may be the above-mentioned fountain code encoding device or fountain code decoding device.

In one embodiment, the transceiver unit 802 is used to obtain the data packet loss rate; the processing unit 801 is used to adjust the weight value of the coded frame in the image group according to the data packet loss rate, and perform fountain coding according to the weight value of the coded frame, to obtain Encode the data packet; transmit the encoded data packet to the decoding device.

In an optional manner, the data packet loss rate is indicated by one of the following parameters:

The ratio of the encoded data packets that the decoding device failed to parse within the preset time period to all the encoded data packets received;

The difference between the first ratio and the second ratio. The first ratio is the ratio of the coded data packets that the decoding device failed to parse in the first time period to all the coded data packets received; the second ratio is the ratio of the coded data packets that the decoding device failed to parse in the second time period. The ratio of the coded data packets that were not successfully parsed within the segment to all the coded data packets received; where the first time period and the second time period are adjacent time periods.

In an optional manner, the processing unit 801 is specifically configured to adjust the weight value of the encoded frame in the image group according to the data packet loss rate within a preset time period.

In an optional manner, the encoded frame includes at least one of the following: I frame, P frame and B frame; the priority of I frame, P frame and B frame decreases in order; the processing unit 801 is specifically used for :

Within the preset time period, when the data packet loss rate is greater than the packet loss threshold, the weight values of the encoded frames in the image group are adjusted in order of priority. Among them, the sum of the weight values of the encoded frames is the preset value, and the higher priority The weight value of the coded frame is greater than the weight value of the coded frame with lower priority.

In an optional way, the processing unit 801 is also used to:

Obtain the first data packet loss rate in the i-th preset time period, i is a positive integer;

When the first data packet loss rate is greater than the packet loss threshold, adjust the weight value of the encoded frame according to the first strategy, and the first strategy includes increasing the weight value of the encoded frame of the first priority;

Obtain the second data packet loss rate within the i+1 preset time period;

When the second data packet loss rate is less than the first data packet loss rate, adjust the weight value of the encoded frame in the i+2 preset time period according to the first strategy; or, the second data packet loss rate is not less than the first data packet loss rate. When the packet loss rate is determined, adjust the weight value of the encoded frame in the i+2 preset time period according to the second strategy. The second strategy includes reducing the weight value of the encoded frame of the first priority;

Obtain the third data packet loss rate within the i+2 preset time period;

When the third data packet loss rate is less than the second data packet loss rate, the weight value of the encoded frame in the i+3 preset time period is adjusted according to the second strategy, or the third data packet loss rate is not less than the second data packet loss rate. When the packet loss rate is reduced, the weight value of the encoded frame in the i+3 preset time period is adjusted according to the third strategy. The third strategy includes increasing the weight value of the encoded frame of the second priority.

In an optional manner, the processing unit 801 is also configured to: if the data packet loss rate in any preset time period is less than the packet loss threshold, not adjust the weight value of the encoded frame.

In an optional approach, the default value is 1.

In an optional manner, the processing unit 801 is specifically used for:

The data packet loss rate is input into the weight adjustment model and one or more of the following algorithms are used to determine the weight value of the encoded frame in the image group: Monte Carlo algorithm, back propagation algorithm, Newton gradient method, one-dimensional search algorithm .

In an optional method, the encoded data packet includes: the position of the encoded frame and the degree value of the fountain encoding.

In one embodiment, the transceiver unit 802 is used to receive encoded data packets; the encoded data packets are determined by fountain coding according to the weight value of the encoded frame; the processing unit 801 is used to parse the encoded data packets to obtain video data.

In an optional manner, the processing unit 801 is used to determine the data packet loss rate; the transceiver unit is used to feed back the data packet loss rate to the encoding device.

In an optional manner, the data packet loss rate is indicated by one of the following parameters:

The ratio of the encoded data packets that the decoding device failed to parse within the preset time period to all the encoded data packets received;

The difference between the first ratio and the second ratio. The first ratio is the ratio of the coded data packets that the decoding device failed to parse in the first time period to all the coded data packets received; the second ratio is the ratio of the coded data packets that the decoding device failed to parse in the second time period. The ratio of the coded data packets that were not successfully parsed within the segment to all the coded data packets received; where the first time period and the second time period are adjacent time periods.

As shown in FIG. 9 , a fountain code processing device 900 is also provided in this application. The fountain code processing device 900 may be a chip or a chip system. The fountain code processing device may be located in the device involved in any of the above method embodiments, such as an image encoding device or an image decoding device, to perform actions corresponding to the device.

Optionally, the chip system may be composed of chips, or may include chips and other discrete devices.

The fountain code processing device 900 includes a processor 910 .

The processor 910 is configured to execute the computer program stored in the memory 920 to implement the actions of each device in any of the above method embodiments.

The fountain code processing device 900 may also include a memory 920 for storing a computer program.

Optionally, memory 920 and processor 910 are coupled. Coupling is an indirect coupling or communication connection between devices, units or modules, which can be in electrical, mechanical or other forms, and is used for information interaction between devices, units or modules. Optionally, the memory 920 is integrated with the processor 910 .

There can be one or more processors 910 and memories 920 without limitation.

Optionally, in practical applications, the fountain code processing device 900 may or may not include the transceiver 930 , as shown by a dotted box in the figure. The fountain code processing device 900 may perform processing through the transceiver 930 and other devices. Information exchange. The transceiver 930 may be a circuit, a bus, a transceiver, or any other device that may be used for information exchange.

The specific connection medium between the above-mentioned transceiver 930, processor 910 and memory 920 is not limited in the embodiment of the present application. In the embodiment of the present application, the memory 920, the processor 910 and the transceiver 930 are connected through a bus in Figure 9. The bus is represented by a thick line in Figure 9. The connection methods between other components are only schematically explained. It is not limited. The bus can be divided into address bus, data bus, control bus, etc. For ease of presentation, only one thick line is used in Figure 6, but it does not mean that there is only one bus or one type of bus. In the embodiment of the present application, the processor may be a general-purpose processor, a digital signal processor, an application-specific integrated circuit, a field programmable gate array or other programmable logic device, a discrete gate or transistor logic device, or a discrete hardware component, and may implement or Execute each method, step and logical block diagram disclosed in the embodiment of this application. A general-purpose processor may be a microprocessor or any conventional processor, etc. The steps of the methods disclosed in conjunction with the embodiments of the present application can be directly implemented by a hardware processor for execution, or can be executed by a combination of hardware and software modules in the processor.

In the embodiment of the present application, the memory may be a non-volatile memory, such as a hard disk drive (HDD) or a solid-state drive (SSD), etc., or it may be a volatile memory (volatile memory), such as a random access memory. Access memory (random-access memory, RAM). Memory may also be, but is not limited to, any other medium that can be used to carry or store desired program code in the form of instructions or data structures and that can be accessed by a computer. The memory in the embodiment of the present application can also be a circuit or any other device capable of performing a storage function, used to store computer programs, program instructions and/or data.

Based on the above embodiments, referring to Figure 10, the embodiment of the present application also provides another fountain code processing device 1000, including: an interface circuit 1010 and a logic circuit 1020; the interface circuit 1010 can be understood as an input and output interface, and can be used to perform any of the above. Transmitting and receiving steps of each device in a method embodiment; the logic circuit 1020 can be used to run codes or instructions to perform the method performed by each device in any of the above embodiments, which will not be described again.

Based on the above embodiments, embodiments of the present application also provide a computer-readable storage medium that stores instructions. When the instructions are executed, each device in any of the above method embodiments is executed. For example, the method performed by the fountain code encoding device and the fountain code decoding device in the embodiment shown in FIG. 5 is implemented. The computer-readable storage medium may include: U disk, mobile hard disk, read-only memory, random access memory, magnetic disk or optical disk and other various media that can store program codes.

Based on the above embodiments, embodiments of the present application provide a fountain code processing system. The communication system includes the fountain code encoding device and the fountain code decoding device mentioned in any of the above method embodiments, and can be used to execute any of the above method embodiments. Methods executed by each device.

Those skilled in the art will understand that embodiments of the present application may be provided as methods, systems, or computer program products. Accordingly, the present application may take the form of an entirely hardware embodiment, an entirely software embodiment, or an embodiment that combines software and hardware aspects. Furthermore, the present application may employ computer-usable storage media (including but not limited to magnetic disk storage, compact disc read-only memory (CD-ROM)) containing computer-usable program code therein. , optical storage, etc.).

The present application is described with reference to flowchart illustrations and/or block diagrams of methods, apparatus (systems), and computer program products according to the present application. It will be understood that each process and/or block in the flowchart illustrations and/or block diagrams, and combinations of processes and/or blocks in the flowchart illustrations and/or block diagrams, can be implemented by computer program instructions. These computer program instructions may be provided to a processor of a general purpose computer, special purpose computer, embedded processor or other programmable data processing device to produce a machine such that the instructions executed by the processor of the computer or other programmable data processing device produce a A device for realizing the functions specified in one process or multiple processes of the flowchart and/or one block or multiple blocks of the block diagram.

These computer program instructions may also be stored in a computer-readable memory that causes a computer or other programmable data processing apparatus to operate in a particular manner, such that the instructions stored in the computer-readable memory produce an article of manufacture including the instruction apparatus, the instructions The device implements the functions specified in a process or processes of the flowchart and/or a block or blocks of the block diagram.

These computer program instructions may also be loaded onto a computer or other programmable image processing device, causing a series of operating steps to be performed on the computer or other programmable device to produce computer-implemented processing, thereby executing on the computer or other programmable device. Instructions provide steps for implementing the functions specified in a process or processes of a flowchart diagram and/or a block or blocks of a block diagram.

Claims (15)

1. A fountain code encoding method, characterized by including: Get the data packet loss rate; Adjust the weight value of the encoded frame in the image group according to the data packet loss rate; Perform fountain coding according to the weight value of the coded frame to obtain a coded data packet; The encoded data packet is transmitted to the decoding device. 2. The method according to claim 1, characterized in that the data packet loss rate is indicated by one of the following parameters: The ratio of the coded data packets that were not successfully parsed by the decoding device within a preset time period to all coded data packets received; The difference between a first ratio and a second ratio, where the first ratio is the ratio of the coded data packets that were not successfully parsed by the decoding device within the first time period to all the coded data packets received; the second ratio is The ratio of the coded data packets that were not successfully parsed by the decoding device in the second time period to all the coded data packets received; wherein the first time period and the second time period are adjacent time periods. 3. The method according to claim 1 or 2, characterized in that adjusting the weight value of the encoded frame in the image group according to the data packet loss rate includes: Within a preset time period, the weight value of the encoded frame in the image group is adjusted according to the data packet loss rate. 4. The method according to claim 3, wherein the encoded frame includes at least one of the following: I frame, P frame and B frame; the I frame, the P frame and the B frame The priorities are reduced in order; the adjustment of the weight value of the encoded frame in the image group according to the data packet loss rate includes: Within the preset time period, when the data packet loss rate is greater than the packet loss threshold, the weight values of the coded frames in the image group are adjusted sequentially according to the priority order, wherein the sum of the weight values of the coded frames is the predetermined Assume that the weight value of the coded frame with high priority is greater than the weight value of the coded frame with low priority. 5. The method according to claim 4, characterized in that when the data packet loss rate is greater than a packet loss threshold, adjusting the weight values of the encoded frames in the image group sequentially according to the priority order, further comprising: Obtain the first data packet loss rate within the i-th preset time period, where i is a positive integer; When the first data packet loss rate is greater than the packet loss threshold, the weight value of the encoded frame is adjusted according to a first strategy, and the first strategy includes increasing the weight value of the encoded frame of the first priority; Obtain the second data packet loss rate within the i+1 preset time period; When the second data packet loss rate is less than the first data packet loss rate, adjust the weight value of the encoded frame in the i+2 preset time period according to the first strategy; or, the second data When the packet loss rate is not less than the first data packet loss rate, adjust the weight value of the encoded frame within the i+2 preset time period according to a second strategy, where the second strategy includes lowering the first priority The weight value of the encoded frame; Obtain the third data packet loss rate within the i+2 preset time period; When the third data packet loss rate is less than the second data packet loss rate, the weight value of the encoded frame in the i+3 preset time period is adjusted according to the second strategy, or the third data packet loss rate is When the packet loss rate is not less than the second data packet loss rate, adjust the weight value of the encoded frame in the i+3 preset time period according to the third strategy. The third strategy includes increasing the encoding of the second priority. The weight value of the frame. 6. The method according to claim 4 or 5, characterized in that adjusting the weight value of the encoded frame in the image group according to the data packet loss rate further includes: If the data packet loss rate in any preset time period is less than the packet loss threshold, the weight value of the encoded frame will not be adjusted. 7. The method according to any one of claims 4-6, characterized in that the preset value is 1. 8. The method according to any one of claims 1-3, characterized in that adjusting the weight value of the encoded frame in the image group according to the data packet loss rate includes: The data packet loss rate is input into the weight adjustment model, and one or more of the following algorithms are used to determine the weight value of the encoded frame in the image group: Monte Carlo algorithm, back propagation algorithm, Newton gradient method, one-dimensional search algorithm. 9. The method according to any one of claims 1 to 8, characterized in that the encoded data packet includes: the position of the encoded frame and the degree value of the fountain encoding. 10. A fountain code decoding method, characterized by including: Receive the encoded data packet; the encoded data packet is determined by fountain coding according to the weight value of the encoded frame; The encoded data packet is parsed to obtain video data. 11. The method of claim 10, further comprising: Determine the data packet loss rate; Feed back the data packet loss rate to the encoding device. 12. The method according to claim 11, characterized in that the data packet loss rate is indicated by one of the following parameters: The ratio of the encoded data packets that the decoding device failed to parse within the preset time period to all the encoded data packets received; The difference between a first ratio and a second ratio, where the first ratio is the ratio of the coded data packets that were not successfully parsed by the decoding device within the first time period to all the coded data packets received; the second ratio is The ratio of the coded data packets that were not successfully parsed by the decoding device in the second time period to all the coded data packets received; wherein the first time period and the second time period are adjacent time periods. 13. A fountain code encoding device, characterized in that it includes: a mutually coupled non-volatile memory and a processor, the processor calls the program code stored in the memory to execute any of claims 1-9 The method described in one item. 14. A fountain code decoding device, characterized in that it includes: a mutually coupled non-volatile memory and a processor, the processor calls the program code stored in the memory to execute any of claims 10-12 The method described in one item. 15. A computer-readable storage medium, characterized in that the computer-readable storage medium stores program code, and the program code includes instructions for a processor to execute the method according to any one of claims 1-12 .