CN102143377A - Video stream delay factor monitoring method and video stream delay factor monitoring device - Google Patents

Abstract

The invention provides a video stream delay factor monitoring method and device. The method includes: determining whether the delay factor of the video stream in the previous sampling period is less than a preset threshold value; The arrival time of the packet and the program clock reference in the packet determine the delay factor of the video stream for the current sampling period. The invention reduces the requirement for storage space in the process of video monitoring, and realizes the purpose of monitoring the quality of large-flow video streams.

Description

Video stream delay factor monitoring method and device

technical field

The invention relates to communication technology, in particular to a method and device for monitoring video stream delay factors.

Background technique

Internet Protocol Television (IPTV for short) transmits IPTV programs in real time through the network. Network transmission is likely to have network packet loss and network jitter, which seriously affects user experience. In video transmission, a large amount of delayed data packet jitter will cause the terminal buffer resources to be exhausted, resulting in a period of time when the decoder has no content to solve, resulting in a decrease in the quality of the video played on the TV. In many cases, the TV will display a lot of blocky video or just blank.

The Media Delivery Index (MDI) is a measurement index for evaluating the transmission quality of video streams on an IP network. As an industry standard for testing the quality of IP video streaming, MDI includes two indicators: delay factor (DF) and media packet loss rate (MLR). The DF value indicates the jitter condition of the tested video stream. DF converts the change of the jitter of the video stream into the demand for buffering of the decoding device. The greater the jitter of the video stream under test, the greater the DF value. The existing video quality monitoring method stores the arrival time and the number of bytes of all data packets in the current sampling period when monitoring the DF value. However, storing the arrival time and the number of bytes of the data packets needs to occupy the storage space of the monitoring device, especially when the video quality of a large flow is monitored, the storage space occupied is larger.

Contents of the invention

Embodiments of the present invention provide a video stream delay factor monitoring method and device, which reduce the storage space requirement in the video monitoring process and realize the purpose of monitoring the quality of large-flow video streams.

An embodiment of the present invention provides a video stream delay factor monitoring method, including:

Determine whether the delay factor of the video stream in the previous sampling period is less than a preset threshold;

When the delay factor of the video stream in the previous sampling period is less than the preset threshold value, according to the arrival time of the program clock reference data packet contained in the video stream of the current sampling period and the program clock reference in the data packet, determine the time delay of the video stream in the current sampling period delay factor.

An embodiment of the present invention provides a video stream delay factor monitoring device, including: a stream allocation module and an estimation module;

The stream allocation module is used to determine whether the delay factor of the video stream in the previous sampling period is less than a preset threshold, and when the delay factor of the video stream in the previous sampling period is less than the preset threshold, notify the estimation module to determine the current sampling period Latency factors for video streams;

The estimation module is configured to, after receiving the notification from the stream allocation module, determine the current sampling period video stream according to the arrival time of the program clock reference data packet contained in the current sampling period video stream and the program clock reference in the data packet. Stream delay factor.

In the video stream delay factor monitoring method and device provided by the embodiments of the present invention, before monitoring the video stream of the current sampling period, first determine whether the video stream of the previous sampling period is a normal video stream through the DF value of the previous sampling period, If the DF value is less than the preset threshold value, the DF value is only determined according to the arrival time of the data packet containing the PCR (program clock reference, program clock reference) and the PCR therein in the current sampling period, and there is no need to store the data packet not containing the PCR Arrival time and byte count. It is only necessary to store the arrival time of the first data packet containing RCR. Therefore, this embodiment does not need to store the arrival time and bytes of all data packets in the current sampling period after determining that the DF value of the previous sampling period is less than the preset threshold. number, thereby reducing the storage space requirements of the video stream monitoring device.

Description of drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings that need to be used in the description of the embodiments or the prior art. Obviously, the accompanying drawings in the following description These are some embodiments of the present invention. For those skilled in the art, other drawings can also be obtained according to these drawings without any creative effort.

Fig. 1 is a flow chart of Embodiment 1 of a method for monitoring video stream delay factors of the present invention;

Fig. 2 is the flow chart of Embodiment 2 of the method for monitoring video stream delay factors of the present invention;

FIG. 3 is a flow chart of Embodiment 3 of the method for monitoring video stream delay factors of the present invention;

FIG. 4 is a structural schematic diagram of Embodiment 1 of a video stream delay factor monitoring device of the present invention;

FIG. 5 is a schematic structural diagram of Embodiment 2 of the video stream delay factor monitoring device of the present invention;

6 is a schematic structural diagram of Embodiment 3 of the device for monitoring delay factors of video streams according to the present invention;

FIG. 7 is a schematic structural diagram of Embodiment 4 of an apparatus for monitoring delay factors of video streams according to the present invention.

Detailed ways

In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments It is a part of embodiments of the present invention, but not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by persons of ordinary skill in the art without making creative efforts belong to the protection scope of the present invention.

When IP data packets are transmitted in the network, they will be sorted, routed, and forwarded by various network devices. Due to various reasons (such as a large amount of P2P traffic, file downloads, and VoIP calls), the network can be temporarily congested, resulting in data passing through The delay of network nodes varies, which is called jitter. Since the instantaneous rate of the data flow arriving at the network node is inconsistent with the processing rate of the network node, the data packet needs to be properly buffered in the buffer area of the network node, and then sent to the video decoder for decoding. The manifestation of jitter on the playback terminal is that there is no data packet in the buffer for decoding by the video decoder, or the space in the buffer area is not enough to accommodate the received data packets, resulting in packet loss. The DF of MDI is a time value, which indicates how many milliseconds of data the buffer must buffer to eliminate jitter, so as not to affect the playback quality.

FIG. 1 is a flow chart of Embodiment 1 of the method for monitoring delay factors of video streams according to the present invention. As shown in Figure 1, this embodiment includes:

Step 11: Determine whether the DF value of the video stream in the previous sampling period is smaller than a preset threshold.

A video stream monitoring device installed at any node in the network monitors the video stream passing through the network node within the sampling period, and analyzes the DF value of the video stream within the sampling period. In the embodiment of the present invention, the DF value determined in each sampling period provides a basis for the strategy for determining the DF value in the next sampling period. When performing DF monitoring on the video stream passing through the network node in the current sampling period, first determine whether the DF value of the video stream in the previous sampling period of the current sampling period is less than a preset threshold. If the DF value of the video stream in the previous sampling period is less than the preset threshold, it indicates that the video stream monitored in the previous sampling period can meet the decoding requirements of the decoder, that is, the jitter of the video stream does not affect the quality of video playback, and it is called the video of the previous sampling period. The stream is a normal video stream for transmission. When the DF value of the video stream in the previous sampling period is greater than or equal to the preset threshold, it indicates that the video stream monitored in the previous sampling period cannot meet the decoding requirements of the decoder, and the video stream in the previous sampling period is called a video stream with abnormal transmission.

The performance of the network and the size of the network node buffer will affect the setting of the DF value preset threshold. The DF value preset threshold can be obtained in the laboratory according to the specific number of video streams and the size of the network node buffer area.

Step 12: When the DF value of the video stream in the previous sampling period is less than the preset threshold, determine the DF of the video stream in the current sampling period according to the arrival time of the PCR data packet contained in the video stream of the current sampling period and the PCR in the data packet value.

When the video stream in the last sampling period is a video stream with normal transmission, when determining the DF value of the video stream in the current sampling period, only the PCR data packets contained in the video stream are monitored, and other packets not containing the PCR data packets are not monitored. Since the interval value of two PCRs reflects the actual time required to consume a packet between two packets containing a PCR, the difference in arrival time of two packets containing a PCR reflects the time a packet received after the previous PCR packet was received. The time required after a PCR packet, which includes the delay in transmission. Therefore, the change of the arrival time of the data packet including the PCR and the change of the PCR in the data packet can reflect the change of the consumed data packet in the virtual buffer, thereby reflecting the DF value of the video stream.

In addition, in order to improve monitoring reliability, after determining that the DF value of the previous several consecutive sampling periods is less than the preset threshold value, in the current sampling period, only according to the arrival time of the PCR data packet and the PCR in it, determine the current sampling period. Periodic DF value.

When the DF value of the video stream in the previous sampling period is greater than or equal to the preset threshold, all data packets need to be monitored in the current sampling period. Store the arrival time and number of bytes of all data packets in the current sampling period, and determine the DF value of the video stream in the current sampling period according to the bit rate of the video stream in the current sampling period and the number of bits in the virtual cache before and after the arrival of each data packet in the current sampling period.

In this embodiment, before monitoring the video stream of the current sampling period, it is determined whether the video stream of the previous sampling period is a normal video stream through the DF value of the previous sampling period. If the DF value is less than the preset threshold value, the current sampling period The period only determines the DF value according to the arrival time of the data packet containing the PCR and the PCR therein, without storing the arrival time and the number of bytes of the data packet not containing the PCR. It is only necessary to store the arrival time of the first data packet containing RCR. Therefore, this embodiment does not need to store the arrival time and bytes of all data packets in the current sampling period after determining that the DF value of the previous sampling period is less than the preset threshold. number, thereby reducing the storage space requirements of the video streaming monitoring device. When the DF value of the video stream in the previous sampling period is greater than or equal to the preset threshold, all data packets in the current period are monitored. According to the bit rate of the video stream in the current period and the number of bytes in the virtual cache before and after the arrival of each data packet in the current sampling period, the DF value of the video stream in the current sampling period is accurately calculated, so as to accurately determine whether the video stream in the current sampling period is transmitted normally video stream.

FIG. 2 is a flow chart of Embodiment 2 of the method for monitoring delay factors of video streams according to the present invention. In the embodiment of the present invention, the DF value of the video stream is monitored by a video quality monitoring device installed at any node in the network. The PCR value calculates the DF value, so as to determine the change of the cache in the player that actually plays the video stream. The virtual cache described in the embodiment of the present invention is a term defined in MDI, an industry standard for IP video stream transmission quality testing. The virtual cache is not the actual cache of the video stream monitoring device, but is only used to observe the size of the buffer in the player. The size of the virtual buffer is defined as the difference between the number of bytes received by the video stream monitoring device and the number of bytes required for decoding. The actual cache of the video stream monitoring device is used to cache the arrival time of the first PCR data packet.

As shown in Figure 2, step 12 in Figure 1 includes:

Step 121: According to the arrival time of each PCR-containing data packet and the PCR in each data packet in the current sampling period, determine the first time required to consume the data packets in the virtual cache before each PCR-containing data packet arrives.

When only monitoring the PCR data packets in the video stream to determine the DF value of the video stream in the current sampling period, according to the arrival sequence of the PCR data packets, according to the arrival time of each PCR data packet and the PCR in the data packet, Calculate the time required to consume the data packets in the virtual cache before each data packet containing the PCR arrives at the monitored network node, and record it as the first time.

The specific determination method of each of the above first times can be: according to the difference between the arrival time of the Nth PCR data packet and the arrival time of the first PCR data packet, and the PCR data packet in the Nth PCR data packet. The difference from the PCR in the first PCR-containing packet determines the first time required to consume the packet in the virtual buffer before the Nth PCR-containing packet arrives. The first time corresponding to each PCR data packet is determined until the last PCR data packet received in the current sampling period.

A calculation formula for the first time can be: df(n, pre)=(pcr _n -pcr ₁ )-(t _n -t ₁ ) (Formula 1)

Among them, pcr ₁ represents the ratio of the PCR in the first PCR data packet and 27MHz in the current sampling period; pcr _n represents the ratio of the PCR in the Nth PCR data packet in the current sampling cycle to 27MHz; t _n represents the current The arrival time of the Nth PCR data packet in the sampling period, and _t1 represents the arrival time of the first PCR data packet in the current period. pcr _n -pcr ₁ indicates the time required to consume the data packets received in the current sampling period before the arrival of the Nth PCR data packet; t _n -t ₁ indicates the elapsed time before the arrival of the Nth PCR data packet time. df(n, pre) represents the time required to consume the data in the virtual cache before the Nth PCR packet arrives.

Step 122: Based on the arrival time of each PCR-containing data packet and the PCR in the next PCR-containing data packet of each PCR-containing data packet, determine the time required to consume the data packets in the virtual buffer after each PCR-containing data packet arrives the second time.

For the second time corresponding to the PCR data packet, according to the arrival sequence of the PCR data packet, according to the arrival time of each PCR data packet and the PCR in the next PCR data packet, the arrival time of each PCR data packet is calculated. The time required for the monitored network node to consume the data packets in its virtual cache is recorded as the second time.

The specific method for determining each of the above second times can be: according to the difference between the arrival time of the Nth PCR data packet and the arrival time of the first PCR data packet, and the N+1th PCR data packet. The difference between the PCR and the PCR in the first data packet containing the PCR determines the second time required to play the data packet in the virtual cache after the arrival of the Nth data packet containing the PCR. The first time corresponding to each PCR data packet is determined until the last PCR data packet received in the current sampling period.

A calculation formula for the second time can be: df(n, post)=(pcr _n+1 -pcr ₁ )-(t _n -t ₁ ) (Formula 2)

pcr _n+1 means the ratio of PCR to 27MHz in the N+1th PCR data packet in the current sampling period; pcr _n+1 -pcr ₁ means that the current sampling period has been consumed after the arrival of the Nth PCR data packet The time it takes for a packet to be received. df(n, post) represents the time required to consume the data packets in the virtual cache after the arrival of the Nth PCR data packet.

Step 123: Determine the DF value of the video stream in the current sampling period according to each first time and each second time.

Find the minimum value among all the first times determined in step 121, and find the maximum value among all the second times determined in step 122, according to the minimum value in the first time and the value in the second time The maximum value determines the DF value for the current sampling period.

The video stream delay factor monitoring method of this embodiment calculates the first time required for each data packet to consume the data packet in the virtual buffer before reaching the network node in a sampling period, and determines the time required for the data packet in the virtual buffer to be consumed before the data packet arrives at the network node. and calculate the second time required to consume the data packets in the virtual cache after each data packet arrives at the network node in the sampling period, and determine the maximum time required to consume the data packets in the virtual cache after the data packet arrives at the network node . The difference between the above-mentioned maximum time and minimum time can reflect the change in the time required to consume data packets in the virtual cache before and after the arrival of the data packet in the sampling period, so that it can be estimated how much time the network node needs to buffer data in the sampling period Only packets can smooth the jitter of the video stream, that is, the DF value of the video stream within the sampling period.

FIG. 3 is a flow chart of Embodiment 3 of the method for monitoring delay factors of video streams according to the present invention. In this embodiment, "determining the DF value of the video stream according to the arrival time of the data packet containing the PCR and the PCR in the data packet" is called the DF value estimation method, and "according to the bit rate of the media stream and the time before and after the arrival of each data packet The number of bits in the virtual cache determines the DF value of the video stream" is called the DF value actuarial method. In this embodiment, when determining whether the video stream flowing into the network node in the previous sampling period is a video stream with normal transmission, different preset thresholds are used for comparison according to the method of calculating the DF value in the previous sampling period.

As shown in Figure 3, this embodiment includes:

Step 31: Whether to determine the DF value of the video stream according to the DF value estimation method in the previous sampling period. If yes, go to step 32, otherwise go to step 33.

Step 32: Determine whether the DF value of the video stream in the previous sampling period is smaller than the estimated preset threshold. If not execute step 34, if yes execute step 35.

The estimation preset threshold is a standard for judging whether the video stream is a normal video stream after the DF value of the video stream is determined by the DF value estimation method.

Step 33: Determine whether the DF value of the video stream in the previous sampling period is smaller than the actuarial preset threshold. If not execute step 34, if yes execute step 35.

The actuarial preset threshold value is a standard for judging whether the video stream is a normal video stream after the DF value of the video stream is determined by the DF value actuarial method.

Step 34: Use the DF value actuarial method to determine the DF value of the video stream in the current sampling period.

Step 35: Receive the data packets entering the network node in the current sampling period.

Step 36: Determine whether the data packet contains PCR. If PCR is included, execute step 37, otherwise return to step 35 for execution.

If the header of the data packet contains a PCR field, it indicates that the data packet contains a PCR.

Step 37: Calculate the first time required for the data packet to consume the data packet in the virtual cache before reaching the network node.

For the calculation of the first time, refer to Formula 1.

Step 38: Calculate the second time required for the data packet in the virtual cache to be consumed after the last PCR data packet of the data packet arrives at the network node.

The currently received data packet is the Nth data packet containing the PCR, and the second time required for the data packet in the virtual cache to be consumed after the N-1th data packet containing the PCR arrives at the network node is calculated. The specific calculation method of calculating the second time of the N-1th packet containing PCR data adopts the deformation of formula 2, specifically: df(n-1, post)=(pcr _n -pcr ₁ )-(t _n-1- t ₁ ). pcr _n-1 indicates the ratio of PCR to 27MHz in the N-1th PCR data packet in the current sampling period; pcr _n-1 -pcr ₁ indicates that the current sampling is consumed after the arrival of the N-1th PCR data packet Period The time it takes for a packet to be received. df(n-1, post) represents the time required to consume the data packets in the virtual cache after the arrival of the N-1 PCR data packet.

Step 39: Whether the current sampling period ends. If it is not finished, return to step 35 for execution, otherwise, execute step 310.

Step 310: Determine the minimum value at all first times and the maximum value at all second times, and calculate the DF value of the video stream in the current sampling period. Then enter the next sampling period.

Find the maximum value max(df _post ) from all df(n, post), find the minimum value min(df _pre ) from df(n, pre), and determine the DF value of the current sampling period. The specific method for determining the DF value is:

DF＝max(df _post )-min(df _pre ) (Formula 3)

In the method for monitoring video stream delay factors in this embodiment, when it is determined that the video stream in the previous sampling period is a normal video stream, the DF value of the video stream in the next sampling period is calculated by using an estimation method that only monitors PCR data packets; When the video stream in one sampling period is an abnormal video stream, the DF value of the video stream in the next sampling period is calculated by using the actuarial method of monitoring all data packets. When judging whether the video stream in the previous sampling period is a normal video stream, different preset thresholds are used according to the method of calculating the DF value in the previous sampling period, thereby improving the reliability of the judgment result. In this embodiment, it is only necessary to cache the arrival time of the first data packet containing PCR within a sampling period, instead of storing the arrival time and the number of bytes of all data packets. Therefore, the requirement for storage space in the process of monitoring the DF value of the video stream is reduced.

FIG. 4 is a schematic structural diagram of Embodiment 1 of an apparatus for monitoring delay factors of video streams according to the present invention. As shown in FIG. 4 , it includes: a flow allocation module 41 and an estimation module 42;

The stream distribution module 41 is used to determine whether the delay factor of the video stream in the previous sampling period is less than the preset threshold value, and when the delay factor of the video stream in the previous sampling period is less than the preset threshold value, notify the estimation module 42 to determine the current sampling period video stream delay factor;

The estimation module 42 is configured to determine the delay factor of the video stream of the current sampling period according to the arrival time of the PCR data packet contained in the video stream of the current sampling period and the PCR in the data packet after receiving the notification from the stream allocation module. Further, as shown in FIG. 5 , this embodiment also includes an actuarial module 43;

The stream allocation module 41 is also used to notify the actuarial module 43 to determine the delay factor of the video stream of the current sampling period when the delay factor of the video stream of the previous sampling period is greater than the preset threshold;

The actuarial module 43 is used to determine the delay factor of the video stream in the current sampling period according to the bit rate of the media stream in the current period and the number of bits in the virtual buffer before and after the arrival of each data packet in the current sampling period after receiving the notification from the stream distribution module.

For the specific operation content of the above modules, refer to the description of the corresponding embodiment in FIG. 1 , which will not be repeated here.

In the video stream delay factor monitoring device of this embodiment, the stream distribution module 41 determines whether the video stream of the previous sampling period is a normal video stream through the DF value of the previous sampling period, and if the DF value is less than the preset threshold value, the estimation module is notified 42 Determine the delay factor of the video stream for the current sampling period. In the current sampling period, the estimation module 42 only determines the DF value according to the arrival time of the data packets containing the PCR and the PCRs therein, and does not need the arrival time and the number of bytes of the data packets not containing the PCR. Therefore, in this embodiment, after it is determined that the DF value in the previous sampling period is less than the preset threshold value, it is not necessary to store the arrival time and the number of bytes of all data packets in the current sampling period, thereby reducing the demand for storage space. In addition, when the DF value of the video stream in the previous sampling period is greater than or equal to the preset threshold, the stream allocation module 41 notifies the actuarial module 43 to monitor all data packets in the current period. According to the bit rate of the video stream in the current period and the number of bytes in the virtual buffer area before and after the arrival of each data packet in the current sampling period, the DF value of the video stream in the current sampling period is accurately calculated, so as to accurately determine whether the video stream in the current sampling period is transmitted normal video stream.

FIG. 6 is a schematic structural diagram of Embodiment 3 of an apparatus for monitoring delay factors of video streams according to the present invention. As shown in Figure 6, the estimation module 42 includes: a first time determination unit 421, a second time determination unit 422 and a delay factor determination unit 423;

The first time determination unit 421 is configured to determine the time required to consume the data packets in the virtual cache before each PCR data packet arrives according to the arrival time of each PCR data packet and the PCR in each data packet in the current sampling period. the first time.

The first time determining unit 421 is specifically configured to use the difference between the arrival time of each PCR data packet and the arrival time of the first PCR data packet, and the difference between the PCR in each PCR data packet and the first PCR data packet. The delta of the PCRs of the PCR packets determines the first time required to consume the packets in the virtual buffer before each packet containing the PCR arrives.

The second time determination unit 422 is configured to determine to consume the virtual buffer after each data packet containing the PCR arrives according to the arrival time of each data packet containing the PCR and the PCR in the next data packet containing the PCR of the data packet The second time required for the packets in .

The second time determining unit 422 is specifically configured to, according to the difference between the arrival time of each PCR data packet and the arrival time of the first PCR data packet, and the next PCR data packet of each PCR data packet. The difference between the PCR and the PCR in the first PCR-containing data packet determines the second time required to consume the data packets in the virtual buffer after each PCR-containing data packet arrives.

The delay factor determination unit 423 is configured to determine the delay factor of the video stream in the current sampling period according to the difference between the minimum value at the first time and the maximum value at the second time.

For the specific operation content of the above modules, refer to the description of the corresponding embodiment in FIG. 2 or FIG. 3 , and details are not repeated here.

In the device for monitoring video stream delay factors in this embodiment, the first time determination unit 421 calculates the first time required for each data packet to consume data packets in the virtual cache before reaching the network node in a sampling period, so as to determine the time consumed in the sampling period. The minimum time required for a packet to flow out of a network node. The second time determination unit 422 calculates the second time required to consume the data packets in the virtual cache after each data packet arrives at the network node in the sampling period, so as to determine the maximum required time for consuming the data packets flowing into the network node in the sampling period. time. The delay factor determining unit 423 can estimate how much data packets need to be virtual buffered by the network node in the sampling period to smooth the jitter of the video stream according to the difference between the above-mentioned maximum time and the minimum time in the sampling period, thus representing the time in the sampling period The DF value of the video stream.

FIG. 7 is a schematic structural diagram of Embodiment 4 of an apparatus for monitoring delay factors of video streams according to the present invention. As shown in FIG. 7 , the flow distribution module 41 includes: a first flow distribution unit 411 and a second flow distribution unit 412 .

The first stream allocation unit 411 is used to determine whether the delay factor of the video stream of the previous sampling period is less than the estimated preset threshold value when the last sampling period estimating module 42 determines the delay factor of the video stream of the previous sampling period; and When the delay factor of the sampling period video stream is less than the estimated preset threshold, the notification estimation module determines the delay factor of the current sampling period video stream; when the delay factor of the video stream of the previous sampling period is greater than or equal to the estimated preset threshold, the notification said The actuarial module determines the delay factor of the video stream for the current sampling period.

The second stream allocation unit 412 is used to determine whether the delay factor of the video stream of the previous sampling period is less than the actuarial preset threshold when the last sampling period actuarial module 43 determines the delay factor of the video stream of the previous sampling period; and When the delay factor of the video stream in a sampling period is less than the actuarial preset threshold value, notify the estimation module to determine the delay factor of the video stream in the current sampling period; when the delay factor of the video stream in the previous sampling period is greater than or equal to the actuarial preset threshold value, notify the The actuarial module determines the delay factor of the video stream for the current sampling period.

Refer to the description of the corresponding embodiment in FIG. 3 for the specific operation content of the above modules, and details are not repeated here.

The device for monitoring delay factors of video streams in this embodiment. When judging whether the video stream in the previous sampling period is a normal video stream, different preset thresholds are used according to the method of calculating the DF value in the previous sampling period, thereby improving the reliability of the judgment result.

Those of ordinary skill in the art can understand that all or part of the steps for realizing the above-mentioned method embodiments can be completed by hardware related to program instructions, and the aforementioned program can be stored in a computer-readable storage medium. When the program is executed, the It includes the steps of the above method embodiments; and the aforementioned storage medium includes: ROM, RAM, magnetic disk or optical disk and other various media that can store program codes.

Finally, it should be noted that: the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that: it can still be Modifications are made to the technical solutions described in the foregoing embodiments, or equivalent replacements are made to some of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the various embodiments of the present invention.

Claims (10)

1. A video stream delay factor monitoring method, is characterized in that, comprising: Determine whether the delay factor of the video stream in the previous sampling period is less than a preset threshold; When the delay factor of the video stream in the previous sampling period is less than the preset threshold value, according to the arrival time of the program clock reference data packet contained in the video stream of the current sampling period and the program clock reference in the data packet, determine the time delay of the video stream in the current sampling period delay factor. 2. The video stream delay factor monitoring method according to claim 1, is characterized in that, also comprises: When the delay factor of the video stream in the previous sampling period is greater than or equal to the preset threshold, the delay factor of the video stream in the current sampling period is determined according to the bit rate of the media stream in the current sampling period and the number of bits in the virtual buffer before and after the arrival of each data packet in the current sampling period . 3. The video stream delay factor monitoring method according to claim 2, wherein determining whether the delay factor of the video stream in the last sampling period is less than a preset threshold comprises: When determining the delay factor of the video stream in the previous sampling period based on the arrival time of the data packet containing the program clock reference and the program clock reference in the data packet in the previous sampling period, determine whether the delay factor of the video stream in the previous sampling period is less than Estimate the preset threshold; When determining the delay factor of the video stream in the previous sampling period according to the bit rate of the media stream and the number of bits in the virtual buffer before and after the arrival of each data packet in the previous sampling period, determine whether the delay factor of the video stream in the previous sampling period is less than Actuarial preset threshold. 4. The video stream delay factor monitoring method according to claim 1, 2 or 3, characterized in that, according to the arrival time of the data packet containing the program clock reference in the video stream according to the current sampling period and the time of arrival in the data packet Program clock reference, which determines the delay factors of the video stream in the current sample period, including: According to the arrival time of each of the data packets containing the program clock reference and the program clock reference in each of the data packets in the current sampling period, it is determined to consume the virtual buffer before each of the data packets containing the program clock reference arrives. The first time the packet is required; According to the arrival time of each of the data packets containing the program clock reference and the program clock reference in the next data packet containing the program clock reference of the data packet, it is determined when each of the data packets containing the program clock reference arrives The second time required to consume packets in the virtual cache afterward; According to each of the first times and each of the second times, the delay factor of the video stream in the current sampling period is determined. 5. video stream delay factor monitoring method according to claim 4, is characterized in that: According to the arrival time of each of the data packets containing the program clock reference and the program clock reference in each of the data packets in the current sampling period, it is determined that before the arrival of each of the data packets containing the program clock reference, the virtual The first time a packet in the cache is required, specifically: Based on the difference between the arrival time of each PCR-containing packet and the arrival time of the first PCR-containing packet, and the difference between the time of arrival of each PCR-containing packet determining the first time required to consume the data packets in the virtual buffer before each data packet containing the program clock reference arrives; According to the arrival time of each data packet containing the program clock reference and the program clock reference in the next data packet containing the program clock reference of the data packet, it is determined when each of the data packets containing the program clock reference arrives The second time required to consume the packets in the virtual cache afterward, specifically: Based on the difference between the arrival time of each PCRD-containing packet and the arrival time of the first PCRD-containing packet, and the program in each next PCRD-containing packet the difference between the clock reference and the program clock reference in the first packet containing the program clock reference, determining a second time required to consume the packets in the virtual buffer after each packet containing the program clock reference arrives; According to each of the first times and each of the second times, determine the delay factor of the current sampling period video stream, specifically: According to the difference between the minimum value at the first time and the maximum value at the second time, determine the delay factor of the video stream in the current sampling period. 6. A device for monitoring video stream delay factors, comprising: a stream distribution module and an estimation module; The stream allocation module is used to determine whether the delay factor of the video stream in the previous sampling period is less than a preset threshold, and when the delay factor of the video stream in the previous sampling period is less than the preset threshold, notify the estimation module to determine the current sampling period Latency factors for video streams; The estimation module is configured to, after receiving the notification from the stream allocation module, determine the current sampling period video stream according to the arrival time of the program clock reference data packet contained in the current sampling period video stream and the program clock reference in the data packet. Stream delay factor. 7. The video stream delay factor monitoring device according to claim 6, further comprising: an actuarial module; The stream allocation module is also used to notify the actuarial module to determine the delay factor of the current sampling period video stream when the delay factor of the video stream in the previous sampling period is greater than a preset threshold; The actuarial module is configured to determine the delay factor of the video stream in the current period according to the bit rate of the media stream in the current period and the number of bits in the virtual buffer before and after the arrival of each data packet in the current sampling period after receiving the notification from the stream allocation module . 8. The video stream delay factor monitoring device according to claim 7, wherein the stream distribution module comprises: The first stream allocation unit is used to determine whether the delay factor of the video stream in the previous sampling period is less than the estimated preset threshold value when determining the delay factor of the video stream in the previous sampling period according to the estimation module in the previous sampling period; and When the delay factor of the video stream of a sampling period is less than the estimated preset threshold value, the estimation module is notified to determine the delay factor of the video stream of the current sampling period; when the delay factor of the video stream of the previous sampling period is greater than or equal to the estimated preset threshold value, Informing the actuarial module to determine the delay factor of the current sampling period video stream; The second stream allocation unit is used to determine whether the delay factor of the video stream in the previous sampling period is less than the actuarial preset threshold value when determining the delay factor of the video stream in the previous sampling period according to the actuarial module in the previous sampling period; and When the delay factor of the video stream in the previous sampling period is less than the actuarial preset threshold value, notify the estimation module to determine the delay factor of the video stream in the current sampling period; when the delay factor of the video stream in the previous sampling period is greater than or equal to the actuarial preset threshold value , notifying the actuarial module to determine the delay factor of the video stream in the current sampling period. 9. The video stream delay factor monitoring device according to claim 6, 7 or 8, wherein the estimation module includes: a first time determination unit, a second time determination unit and a delay factor determination unit; The first time determination unit is configured to determine, according to the arrival time of each of the data packets containing the program clock reference in the current sampling period and the program clock reference in each of the data packets, to determine when each of the data packets containing the program clock reference The first time required to consume a packet in the virtual cache before the packet arrives; The second time determination unit is configured to determine, according to the arrival time of each data packet containing the program clock reference and the program clock reference in the next data packet containing the program clock reference of the data packet, to determine the the second time required to consume the packet in the virtual buffer after the arrival of the packet referenced by the clock; The delay factor determination unit is configured to determine the delay factor of the video stream in the current sampling period according to the difference between the minimum value at the first time and the maximum value at the second time. 10. The video stream delay factor monitoring device according to claim 9, characterized in that: The first time determination unit is specifically configured to use the difference between the arrival time of each packet containing the program clock reference data and the arrival time of the first packet containing the program clock reference data, and the time difference in each packet containing the program clock reference data. The difference between the program clock reference of the program clock reference and the first program clock reference containing the program clock reference data packet determines the first time required to consume the data packets in the virtual buffer before each packet containing the program clock reference data arrives; The second time determination unit is specifically configured to use the difference between the arrival time of each packet containing the program clock reference data and the arrival time of the first packet containing the program clock reference data, and the time difference of each packet containing the program clock reference data. The difference between the program clock reference in the next program clock reference data packet and the program clock reference in the first program clock reference data packet to determine the consumption of data in the virtual buffer after each program clock reference data packet arrives The second time the package takes.

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