WO2010063202A1 - Method and apparatus applied for media delivery quality measurement - Google Patents

Abstract

The present invention discloses a method and apparatus applied for media delivery quality measurement and belongs to Interactive Personality Television (IPTV) field. The method comprises the following steps: receiving data stream, computing rate values according to the feature information of Transport Stream (TS) packets in the data stream, obtaining the maximum one of the computed rate values, based on the feature information of the TS packet with the computed maximum rate value, computing a critical rate value, and computing an ideal media rate according to the maximum rate value and critical rate value. The solution applies the ideal media rate to compute Delay Factor (DF) and Media Loss Rate (MLR), thus enables MLR to be computed accurately even if the situation that data packets are lost continuously and in large quantity happens.

Description

 METHOD AND APPARATUS FOR MEASUREMENT OF MEDIA TRANSMISSION QUALITY MEASUREMENT This application claims to be Chinese patent application filed on Dec. 2, 2008, the Chinese Intellectual Property Office, Application No. 200810179371.5, entitled "Method and Apparatus for Media Transmission Quality Measurement" The priority is hereby incorporated by reference in its entirety.

Technical field

 The present invention relates to the field of IPTV (Interactive Personal Television, Personalized Interactive Television), and in particular, to a method and apparatus for measuring media transmission quality.

Background technique

 In the IPTV service, multimedia content is transmitted to the destination through the IP network. Since the IP network has problems such as delay, jitter, and packet loss, it is necessary to measure the transmission quality of the multimedia content. In the measurement of multimedia content transmission quality, the transmission quality of the video stream in the IP network is evaluated by the Media Delivery Index (MDI) defined in the RFC 4445 document. The MDI consists of two parameters: Delay Factor (DF) Media Loss s Ra te (Media Loss Rate, MLR for short) and DF parameter values indicate the delay and jitter of the video stream being tested; Media Los s Ra te (Media Packet Loss Rate, MLR for short), the MLR parameter value indicates the transmission loss rate of the tested video stream. The definition and test principle of MDI are clearly described in the RFC 4445 document, but the specific calculation methods of the two measurement parameters of DF and MLR are not pointed out and need to be implemented by the user.

 The current multimedia transmission quality measurement implementation method is: first calculating PCR ra te between all TS packets with PCR (program clock reference) information in one calculation period (TS flow between TS packets containing PCR information) Rate), then calculate the average of all PCR rates, and participate in the calculation of the parameter DF as the media ideal rate; the parameter MLR is calculated using Cont in y-tyr (continuous counter) to count whether it is received. The data packet, the continuous counter has a certain counting interval, and the number of received data packets is counted every other counting interval, and the value of one parameter MLR is calculated according to the number of the data packets.

In the process of implementing the above-described multimedia transmission quality measurement implementation method, the inventors found that the prior art At least the following problems exist during surgery:

 First, when there is a packet loss phenomenon in the IP network, the calculated PCR ra te will be small. If the packet loss phenomenon is frequent, there will be multiple 4 small PCR rates. If the media ideal rate is all PCR ra The average value of te, then the calculated media ideal rate will be small and there will be errors. When the media ideal rate is involved in the calculation of the parameter DF, the calculated parameter DF error will be quite large, losing the sense of measurement.

 Second, when the IP network continuously loses too many packets, it is assumed that the IP network continuously loses 17 packets, and the continuous counter has a count interval of [0, 15]. Then, when 17 packets are continuously lost, the continuous counter will have A counting interval is that the data packet is not counted, and the parameter MLR cannot be calculated. There is no measurement result. Summary of the invention

 Embodiments of the present invention provide a method and apparatus for applying media transmission quality measurement to accurately calculate parameters in a transmission quality measurement index MD I .

 In order to achieve the above object, the embodiment of the present invention adopts the following technical solutions:

 A method for measuring media transmission quality, comprising:

 Receiving a data stream, calculating at least one rate value according to the feature information of the TS packet in the data stream; acquiring a maximum rate value among the calculated rate values;

 Calculating a critical rate value based on the feature information of the TS packet that calculates the maximum rate value; obtaining the calculated rate value between the maximum rate value and the critical rate value, according to the maximum rate value and the critical value The rate value between the rate values determines the media ideal rate.

 A device for measuring media transmission quality, comprising:

 a prediction quantity unit, configured to receive a data stream, and calculate at least one rate value according to characteristic information of the TS packet in the data stream;

 An obtaining unit, configured to obtain a maximum rate value among the calculated rate values;

a calculating unit, configured to calculate a critical rate value based on the feature information of the TS packet that calculates the maximum rate value; And a determining unit, configured to obtain the calculated rate value between the maximum rate value and the critical rate value, and determine a media ideal rate according to the rate value between the maximum rate value and the critical rate value.

 The method and device for measuring media transmission quality provided by the embodiment of the present invention first selects the maximum value of all the transmitted data streams when calculating the ideal rate of the media, because the maximum rate value corresponds to the largest number of data packets, The number of lost packets is minimal or there is no loss of packets; then a critical rate value is calculated based on the maximum rate value, taking into account some errors introduced by the sender when generating the data stream. Thus, the media ideal rate error calculated from the maximum rate value and the critical rate value is small, and the static error existing in the device is also considered, and the calculated value is more reasonable and accurate. Avoid large errors caused by the average of all calculated transport streams when a packet loss occurs.

 The media ideal rate calculated according to the manner provided by the embodiment of the present invention is applied to the measurement of the DF and the MLR. Since the ideal rate of the media calculated by the embodiment of the present invention is relatively accurate, the final measured DF and MLR are also relatively relatively high. Accurate, the purpose of calculating the parameters of the transmission quality measurement index MDI more accurately is realized.

BRIEF DESCRIPTION OF THE DRAWINGS The accompanying drawings, which are set forth in the description of the claims Other drawings may also be obtained from these drawings without the use of creative labor.

 1 is a flowchart of a method for measuring media transmission quality in Embodiment 1 of the present invention; FIG. 2 is a block diagram of an apparatus for mass media quality measurement according to Embodiment 1 of the present invention; FIG. 3 is applied to Embodiment 1 of the present invention; FIG. 4 is a block diagram of a device for mass media quality measurement according to Embodiment 2 of the present invention; FIG. 5 is a flowchart of a method for media media quality measurement according to Embodiment 3 of the present invention; It is a block diagram of a device applied to media transmission quality measurement in Embodiment 3 of the present invention.

detailed description The technical solutions in the embodiments of the present invention are clearly and completely described in the following with reference to the accompanying drawings in the embodiments of the present invention. It is obvious that the described embodiments are only a part of the embodiments of the present invention, but not all of the embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative efforts are within the scope of the present invention.

 Example 1:

 This embodiment provides a method for measuring media transmission quality, which is mainly used to obtain an ideal media rate for calculating a transmission quality measurement indicator MDI. After obtaining the media ideal rate by using the method, The media ideal rate is applied to the calculation of the parameter DF and the parameter MLR. The following describes the calculation process of the ideal rate of the media. As shown in Figure 1, the calculation of the ideal rate of the media includes the following steps:

 101. Receive a data stream, and calculate at least one rate value according to the feature information of the TS packet in the data stream, where the rate value is a data flow rate between two data packets with PCR information.

 Generally, the foregoing feature information mainly refers to: the number of TS packets between two TS packets carrying PCR information, and the PCR information of the two TS packets. The method for calculating multiple data stream rates is as follows: Let the two packets with PCR information contain the number of bytes i and ii respectively, and the PCR values of the two packets are PCR (i) and PCR (ii), and the calculation of the PCR value is divided into two types. : One case is when the system clock frequency is 27MHZ: PCR (i) = PCR_base (i) * 300 + PCR_ext (i); another case is when the system clock frequency is 90KHZ: PCR (i ) =PCR_base (i) * 300.

 Data stream rate = [ ( i + i i ) * system clock frequency ] / [PCR ( i ) -PCR ( i i ) ].

 A plurality of the plurality of data stream rate values described above refer to a number greater than 1, and may be adjusted as needed, for example, a positive integer greater than one. Multiples can also refer to the rate values calculated over a period of time before a point in time, which can be adjusted as needed, for example: 1 second, 2 seconds, etc.

 102. Obtain a maximum rate value among the calculated rate values, that is, find the largest one of the plurality of calculated data stream rate values.

103. Calculate a critical rate based on the feature information of the TS packet that calculates the maximum rate value. The value, the critical rate value is a value slightly smaller than the maximum rate value, and the specific calculation method includes but is not limited to the following manner:

 First, the number of data packets corresponding to the maximum rate value is decremented by one, and the corresponding number of bytes is calculated; and the time between the two packets with PCR information corresponding to the maximum rate value is determined; The number of bytes obtained is divided by the time to obtain a critical rate value.

 1 04. Obtain a calculated rate value between the maximum rate value and a critical rate value, and determine a media ideal rate according to a rate value between the maximum rate value and a critical rate value, where the media ideal rate may be applied. Go to the calculation of the parameter DF and the parameter MLR.

 In a specific application, the DF or MLR may be calculated according to the above-mentioned media ideal rate, and the received data stream used in calculating the DF or MLR may be the data stream received when calculating the ideal rate of the medium, or may be in the calculation The data stream received again after the media ideal rate is completed.

 Corresponding to the method for the media transmission quality measurement described in FIG. 1, the embodiment of the present invention further provides an apparatus for measuring media transmission quality. As shown in FIG. 2, the apparatus includes: a prediction quantity unit 21, an acquisition unit 22 , a calculation unit 23 and a determination unit 24.

 The predicting unit 21 is configured to receive the data stream, and calculate at least one rate value according to the feature information of the TS packet in the data stream. The specific calculation method is shown in the description of the process in FIG. 1; the obtaining unit 22 is configured to obtain the calculation. a maximum rate value out of the rate value; the calculating unit 23 is configured to calculate a critical rate value based on the feature information of the TS packet that calculates the maximum rate value; the determining unit 24 is configured to obtain the calculated maximum rate A rate value between the value and the critical rate value, the media ideal rate being determined based on the rate value between the maximum rate value and the critical rate value.

 The above feature information mainly refers to the number of TS packets between two TS packets carrying PCR information and the PCR information of the two TS packets.

The method and device for measuring media transmission quality provided by the embodiment of the present invention first selects the maximum value of all the transmitted data streams when calculating the ideal rate of the media, because the maximum rate value corresponds to the largest number of data packets, The minimum number of lost packets or no loss of packets; then a critical rate value is calculated based on the maximum rate value, taking into account the sender Some errors are introduced into the data stream. Thus, the media ideal rate error calculated from the maximum rate value and the critical rate value is small, and the static error existing in the device is also considered, and the calculated value is more reasonable and accurate. Avoid large errors caused by the average of all calculated transport streams when a packet loss occurs.

 The media ideal rate calculated according to the manner provided by the embodiment of the present invention is applied to the measurement of the DF and the MLR. Because the accurate media ideal rate calculated by the embodiment of the present invention, the final measured DF and MLR are also relative. More accurate.

 Example 2:

 In this embodiment, the method for calculating the quality of the media transmission is described by taking the calculation of the delay parameter (DF) as an example. After calculating the ideal rate of the medium according to the method of FIG. 1, the delay parameter is calculated according to the calculated ideal rate of the medium, as shown in the figure. As shown in 3, the method includes the following steps:

 301. Calculate a plurality of data stream rate values, where the rate value is a data stream rate between two packets with PCR information.

 The method for calculating multiple data stream rates is as follows: Let two packets with PCR information contain i and ii respectively, and the PCR values of the two packets are PCR (i) and PCR (ii) , The calculation of the PCR value is divided into two types: One case is the calculation method when the system clock frequency is 27 MHz: PCR (i) = PCR_ba se (i) * 300 + PCR_ext (i); the other case is the system The calculation method when the clock frequency is 90KHZ: PCR (i) = PCR_base (i) * 300.

 Data stream rate = [ ( i + i i ) * system clock frequency ] / [PCR ( i ) -PCR ( i i ) ].

 A plurality of the plurality of data stream rate values described above refer to a number greater than 1, and may be adjusted as needed, for example, a positive integer greater than one. Multiples can also refer to the rate values calculated over a period of time before a point in time, which can be adjusted as needed, for example: 1 second, 2 seconds, etc.

 302. Select, according to the calculated multiple data stream rate values, a maximum value as the maximum rate value.

 303. Decrement the number of data packets corresponding to the maximum rate value by one, and obtain a corresponding number of bytes.

304. Determine a time taken when the maximum rate value is calculated, that is, when the maximum rate value is obtained. The time between two packets with PCR information.

 305. Divide the number of bytes by the time to obtain a critical rate value.

 The critical rate is proposed here, considering that the source device generates a data stream, which introduces some errors. The byte error caused by this type of situation is less than the number of bytes of a packet. When a packet loss occurs, the number of bytes lost is inevitable. Not less than the number of bytes of a packet, so the rate maximum corresponds to the number of packets minus one and then calculates the critical rate.

 306. Count a data stream rate value in a range from a critical rate value to a maximum rate value as a media ideal rate.

 The method for calculating the ideal rate of the medium may be, but not limited to, the following two methods: First, the data stream rate value with the highest frequency occurring in the statistical critical rate value and the rate maximum interval is used as the media ideal rate.

 Second, calculate the average of all data stream rate values in the critical rate value and rate maximum interval as the media ideal rate.

 The value of the parameter DF is calculated every other cycle. After one calculation cycle period, the DF restarts the calculation.

 307. Find the number of bytes of the data packet saved before the current received data packet in the received data stream (set to variable a), and count the number of bytes of the current received data packet and save (set to variable b), and record from Start measuring the time taken to receive the current packet (set to variable t).

 The received data stream referred to in this process refers to: the data stream received when calculating the ideal rate of the medium, or the data stream received again after calculating the ideal rate of completion of the medium.

 308. Determine whether the calculation period is over. The calculation period is usually 1 second, and can also be adjusted as needed. If the calculation period is exceeded, step 312 is performed; when the calculation period is not exceeded, step 309 is performed.

309. Subtract the saved data packet number a from the product of the media ideal rate and the recorded time t to obtain a virtual cache height value, and save. That is: virtual cache height value l = a - media ideal rate * t. 31 0. Subtract the sum of the saved packet byte number a and the current received packet byte number b minus the media ideal rate and the recorded time t to obtain another virtual cache height value, and save. That is: virtual cache height value 2 = ( a + b ) - media ideal rate * t.

 31 1. Add the number of bytes of the currently received packet b to the number of bytes of the saved packet a to update the value of a, and then go to step 307. That is: a+b update replaces &.

 The above processes 308 to 311 perform the preprocessing process in the DF calculation, that is, calculate the two packet virtual cache height values each time a data is received in the calculation period.

 312. Divide the difference between the maximum value and the minimum value of all the calculated virtual cache height values by the media ideal rate to obtain a delay parameter. That is: DF= (maximum value in virtual cache height value - minimum value in virtual cache height value) / media ideal rate.

 31 3. Determine if there is an end measurement message. If there is an end measurement message, the process ends; otherwise, step 314 is performed.

 314. Subtract the time t obtained by the network protocol packet that has just been received but has exceeded one calculation period by the time obtained by the calculation period, as the receiving time t of the data packet exceeding the current calculation period, so as to restart The calculation of the parameter DF for one cycle, the saved number of bytes a is cleared, and returns to step 308.

 Because the process of calculating the parameter DF is to receive the data packet first, the number of bytes of the received data packet is counted and then it is judged whether the period exceeds the period. After the step 308 is judged, if the period is exceeded, the step 312 is directly executed to calculate the parameter DF, and the calculation is not performed. The virtual cache height value of the packet that exceeds the period received at this time is not saved.

For example: If the period is 1 second, a packet is received every 80 milliseconds, then the first 13 packets are received t=l. 04 seconds, more than one cycle, and a DF value is calculated for the first 12 packets. However, for the 13th data packet, the corresponding two virtual cache height values are not calculated. Because the period is exceeded, the period DF needs to be recalculated, and the time of receiving the data packet needs to be updated, _t ' =1. 04 -1 = 0.04 seconds, using t ' to calculate the two virtual cache height values of the 13th packet.

Corresponding to the method for calculating the DF value described in FIG. 3, the embodiment of the present invention further provides a medium for media. The apparatus for measuring the body transmission quality is used to calculate the DF value. As shown in FIG. 4, the apparatus includes: a prediction amount unit 41, an acquisition unit 42, a calculation unit 43, a determination unit 44, and a delay parameter calculation unit 45.

 The prediction unit 41 is configured to receive the data stream, and calculate at least one rate value according to the feature information of the TS packet in the data stream. The specific calculation method is shown in the description of the 301 process in FIG. 3; the obtaining unit 42 is configured to obtain the calculation. a maximum rate value out of the rate value; the calculating unit 43 is configured to calculate a critical rate value based on the feature information of the TS packet that calculates the maximum rate value; the determining unit 44 is configured to obtain the calculated maximum rate And a rate value between the value and the critical rate value, determining a media ideal rate according to the rate value between the maximum rate value and the critical rate value; the delay parameter calculating unit 45 is configured to calculate the delay parameter according to the media ideal rate.

 In order to prevent the error of the obtained media ideal rate, the present embodiment uses the critical rate value and the maximum rate value to define the range of the media ideal rate. In order to obtain a reasonable critical rate value, the calculation is performed in this embodiment. The unit 43 specifically includes: a pre-processing module 431 and a dividing module 432.

 The pre-processing module 431 is configured to reduce the number of TS packets for which the maximum rate value is calculated by one, and obtain a corresponding number of bytes; and determine, according to the PCR information, a time used for calculating the maximum rate value; the dividing module 432 A method for dividing the number of bytes by the time to derive a critical rate value.

 In order to ensure that the finally determined media ideal rate is a data that is closer to the real situation, the implementation of the following two determining units 44 is provided in the embodiment of the present invention:

 First, the determining unit 44 includes a statistic module 441 and a processing module 442, where the statistic module 441 is configured to count the frequencies at which all rate values occur in the maximum rate value and the critical rate value interval; the processing module 442 is configured to use the highest frequency. The rate value is used as the media ideal rate.

 Second, the determining unit 44 includes a calculating module 443 and a processing module 444 (see the dotted line portion in FIG. 4), wherein the calculating module 443 is configured to calculate an average of all data stream rate values in the maximum rate value and the critical rate value interval. Value; processing module 444 is configured to use the average as the media ideal rate.

As shown in FIG. 4, in specific implementation, the delay parameter calculation unit 45 includes: a delay parameter pre- The processing module 451 and the delay parameter calculation module 452; the delay parameter pre-processing module 451 is configured to calculate two packet virtual cache height values each time one data is received in the calculation period; the delay parameter calculation module 452 is configured to calculate the calculation period The difference between the maximum and minimum values of all virtual cache height values is divided by the media ideal rate to obtain the delay parameter.

 The delay parameter pre-processing module 451 may include: a search sub-module 451 1, a statistical sub-module 4512, a recording sub-module 451 3, a first computing sub-module 4514, and a second computing sub-module 4515.

 The locating sub-module 451 1 is configured to search, in the received data stream, the number of data packets that have been saved before the current data packet is received; the statistic sub-module 4512 is configured to count the number of bytes of the current received data packet; and the recording sub-module 451 3 For recording the time taken from the start of the measurement to the current reception of the data packet; the first calculation sub-module 4514 is configured to subtract the product of the saved number of bytes from the media ideal rate and the recorded time to obtain a virtual cache height value; The sub-module 451 5 is configured to subtract the sum of the media ideal rate and the recorded time from the sum of the saved number of bytes and the number of bytes of the received packet to obtain another virtual cache height value.

 The method and device for measuring media transmission quality provided by the embodiment of the present invention first selects the maximum value of all the transmitted data streams when calculating the ideal rate of the media, because the maximum rate value corresponds to the largest number of data packets, The number of lost packets is minimal or there is no loss of packets; then a critical rate value is calculated based on the maximum rate value, taking into account some errors introduced by the sender when generating the data stream. Thus, the media ideal rate error calculated from the maximum rate value and the critical rate value is small, and the static error existing in the device is also considered, and the calculated value is more reasonable and accurate. Avoid large errors caused by the average of all calculated transport streams when a packet loss occurs. When calculating the two virtual buffer height values and using the above calculated accurate media ideal rate, the calculated value of the parameter DF is also relatively accurate.

 Example 3:

In this embodiment, a method for calculating media transmission quality measurement is described by using a computing media packet loss ratio (MLR) as an example. After calculating an ideal media rate according to the method of FIG. 1, calculating a media packet loss rate according to the calculated media ideal rate. As shown in FIG. 5, the method includes the following steps: 501. Calculate a plurality of data stream rate values, where the rate value is a data stream rate between two packets with PCR information.

 The method for calculating multiple data stream rates is as follows: Let two packets with PCR information contain i and ii respectively, and the PCR values of the two packets are PCR (i) and PCR (ii) , The calculation of the PCR value is divided into two types: One case is the calculation method when the system clock frequency is 27 MHz: PCR (i) = PCR_ba se (i) * 300 + PCR_ext (i); the other case is the system The calculation method when the clock frequency is 90KHZ: PCR (i) = PCR_base (i) * 300.

 Data stream rate = [ ( i + i i ) * system clock frequency ] / [PCR ( i ) -PCR ( i i ) ].

 A plurality of the plurality of data stream rate values described above refer to a number greater than 1, and may be adjusted as needed, for example, a positive integer greater than one. Multiples can also refer to rate values calculated over a period of time before a point in time, which can be adjusted as needed, for example, 1 second, 2 seconds, and so on.

 502. Select, according to the calculated multiple data stream rate values, a maximum value as the maximum rate value.

 503. Decrement the number of data packets corresponding to the maximum rate value by one, and obtain a corresponding number of bytes.

 504. Determine a time taken when the maximum rate value is calculated, that is, a time between two packets with PCR information corresponding to the maximum rate value.

 505. Divide the number of bytes by the time to obtain a critical rate value.

 The critical rate is proposed here, considering that the source device generates a data stream, which introduces some errors. The byte error caused by this type of situation is less than the number of bytes of a packet. When a packet loss occurs, the number of bytes lost is inevitable. Not less than the number of bytes of a packet, so the rate maximum corresponds to the number of packets minus one and then calculates the critical rate.

 506. Calculate a data stream rate value in a range from a critical rate value to a maximum rate value as a media ideal rate.

The method for calculating the ideal rate of the medium may be, but not limited to, the following two methods: First, the data stream rate value with the highest frequency occurring in the statistical critical rate value and the rate maximum interval is used as the media ideal rate. Second, calculate the average of all data stream rate values in the critical rate value and the rate maximum interval as the media ideal rate.

 The value of the parameter DF is calculated every other cycle. After one calculation cycle period, the DF restarts the calculation.

 In order to calculate the media packet loss rate, it is necessary to count the number of bytes actually received by the TS packet in the current calculation period, and calculate the number of bytes that should be received in the current calculation period according to the media ideal rate, and finally according to the The number of TS packets received and the number of TS packets actually received are calculated. The media packet loss rate is calculated. For details, see the following process:

 507. Obtain a PCR value of a TS packet with PCR information in the received data stream, and generally, when receiving the data stream, first determine whether the data packet in the data stream contains PCR information, if the data in the data stream includes PCR information. , go to step 508; otherwise, go to 507.

 508. Calculate the PCR value in the data packet containing the PCR information, and save it.

 There are two kinds of calculations for PCR values: one is the calculation method when the system clock frequency is 27 MHz: PCR (i) = PCR_ba se (i) * 300 + PCR_ext (i); the other case is the system clock frequency The calculation method is 90KHZ: PCR (i) = PCR_ba se (i) * 300.

 509. Determine whether a calculation cycle is completed. The calculation period is usually 1 second. If a calculation cycle is completed, then step 810 is performed; otherwise, step 507 is performed.

 51 0. Find the earliest calculated PCR value in the period, set it as variable PCR ( i ), and find the last calculated PCR value, set to variable PCR ( i i ).

 For example: Suppose the calculation period is 1 second, and 10 packets are received within 1 second, but only the 2nd, 3rd, 5th, 6th, 7th, and 9th contain clock reference information, and the computer calculates the corresponding data in order. PCR value, then the earliest calculated PCR value in this cycle is the PCR value of the second packet, and the last calculated PCR value is the PCR value of the ninth packet.

51 1. Calculate a time span corresponding to the first calculated PCR value and the last calculated PCR value, and divide the difference between the two PCR value by the system clock frequency to obtain the time span, and set the variable as a variable. T, ie: T = [PCR (i) - PCR ( ii ) ] eight system clock frequency. 512. Multiply the time span T by the media ideal rate to obtain the number of bytes that should be received, that is, the number of bytes receivable = Τ * media ideal rate.

 513. Divide the difference between the number of bytes that should be received and the number of bytes actually received by 188 to obtain the number of lost packets, and divide by the calculation period to obtain the value of the parameter MLR, namely: MLR= (the number of bytes receivable - The number of received bytes) / (188 * calculation cycle).

 514. Determine whether there is an end measurement message. If there is an end measurement message, the process ends; otherwise, step 507 is performed.

 Corresponding to the method for calculating the media packet loss rate described in FIG. 3, the embodiment of the present invention further provides a device for media transmission quality measurement, which is used to calculate a media packet loss rate. As shown in FIG. 6, the device includes: The prediction amount unit 61, the acquisition unit 62, the calculation unit 63, the determination unit 64, and the media packet loss rate calculation unit 65.

 The prediction unit 61 is configured to receive the data stream, and calculate at least one rate value according to the feature information of the TS packet in the data stream. The specific calculation method is as described in the 501 process in FIG. 5; the obtaining unit 62 is configured to obtain the calculation. The maximum rate value of the output rate value; the calculating unit 63 is configured to calculate a critical rate value based on the feature information of the TS packet that calculates the maximum rate value; and the determining unit 64 is configured to obtain the calculated maximum value a rate value between the rate value and the critical rate value, determining a media ideal rate according to the rate value between the maximum rate value and the critical rate value; the media packet loss rate calculating unit 65 is configured to calculate the media loss according to the media ideal rate Package rate.

 In order to prevent the error of the obtained media ideal rate, the present embodiment uses the critical rate value and the maximum rate value to define the range of the media ideal rate. In order to obtain a reasonable critical rate value, the calculation is performed in this embodiment. The unit 63 specifically includes: a pre-processing module 631 and a division module 632.

 The pre-processing module 631 is configured to reduce the number of TS packets for which the maximum rate value is calculated by one, and obtain a corresponding number of bytes; and determine, according to the PCR information, a time used for calculating the maximum rate value; the dividing module 632 A method for dividing the number of bytes by the time to derive a critical rate value.

In order to ensure that the final determined media rate is a data that is closer to the real situation, Ben The implementation of the following two determining units 64 is provided in the embodiment of the invention:

 First, the determining unit 64 includes a statistic module 641 and a processing module 642, where the statistic module 441 is configured to count the frequency at which all rate values occur in the maximum rate value and the critical rate value interval; the processing module 442 is configured to use the highest frequency. The rate value is used as the media ideal rate.

 Second, the determining unit 64 includes a calculating module 643 and a processing module 644 (see the dotted line portion in FIG. 6), wherein the calculating module 643 is configured to calculate an average of all data stream rate values in the maximum rate value and the critical rate value interval. Value; processing module 644 is configured to use the average as the media ideal rate.

 In a specific implementation, the media packet loss rate calculation unit 65 includes: a byte statistics module 651, a byte calculation module 652, and a media packet loss rate calculation module 653. The byte statistics module 651 is configured to count the number of bytes of the TS packet actually received in the current calculation period. The byte calculation module 652 is configured to calculate, according to the media ideal rate, the TS packet that should be received in the current calculation period. The media packet loss rate calculation module 653 is configured to calculate a media packet loss rate according to the number of TS packets that should be received and the number of actually received TS packets, that is, the number of bytes that should be received. Dividing the difference between the number of bytes actually received and 188 to obtain the number of lost packets, and dividing by the calculation period to obtain the value of the parameter MLR, the equivalent of the calculation formula is: MLR= (the number of bytes receivable - the number of bytes received) ) / (188* calculation cycle).

 The byte calculation module 652 includes: an acquisition submodule 6521, a determination submodule 6522, a determination submodule 6523, a first calculation submodule 6524, and a second calculation submodule 6525. The obtaining sub-module 6521 is configured to acquire a PCR value of a TS packet having PCR information in the received data stream; the determining sub-module 6522 is configured to determine whether the calculation period is ended; the determining sub-module 6523 is configured to At the end of the calculation period, the earliest acquired PCR value and the last acquired PCR value are determined in the calculation period; the first calculation sub-module 6524 is configured to calculate a time span between the earliest acquired PCR value and the last acquired PCR value. The second calculation sub-module 6525 is configured to calculate the number of bytes that should be received according to the time span and the media ideal rate.

The method and device for applying the media transmission quality measurement index provided by the embodiment of the present invention, when calculating the ideal rate of the medium, first selecting the maximum value of all the calculated data streams, because the most The large rate value corresponds to the largest number of data packets. At this time, the number of lost data packets is the least or no data packets are lost. Then, a critical rate value is calculated according to the maximum rate value, which is introduced when the data stream is generated by the transmitting end. error. In this way, the media ideal rate error calculated according to the maximum rate value and the critical rate value is small, and the statistical method may be, but not limited to, selecting the highest frequency of the transmission stream rate value or the selection interval from the critical rate value to the maximum rate value interval. The average of all the velocity values in the internal value is more reasonable and accurate. Avoid large errors caused by the average of all calculated transport streams when a packet loss occurs.

 The parameter MLR is calculated by using the above calculated accurate media ideal rate, and also using the difference between the number of bytes that should be received and the number of bytes actually received. The actual number of bytes received is Measured by the device, their difference represents the number of bytes lost in the transmission, which in turn can calculate the number of lost packets in the transmission. The calculated value of the more accurate parameter MLR can also be obtained when there is a continuous loss of a large number of packets. Avoid the problem that the continuous counter does not count the data packets when a large number of packets are lost, and cannot be calculated.

 The method and apparatus for calculating DF in Embodiment 2 above, and the method and apparatus for calculating MLR in Embodiment 3 can be simultaneously implemented in the same embodiment.

 Through the description of the above embodiments, those skilled in the art can clearly understand that the present invention can be implemented by means of software plus necessary general hardware, and of course, by hardware, but in many cases, the former is a better implementation. . Based on such understanding, the technical solution of the present invention, which is essential or contributes to the prior art, may be embodied in the form of a software product stored in a readable storage medium, such as a floppy disk of a computer. A hard disk or optical disk or the like includes instructions for causing a computer device (which may be a personal computer, a server, or a network device, etc.) to perform the methods described in various embodiments of the present invention.

 The above is only the specific embodiment of the present invention, but the scope of the present invention is not limited thereto, and any change or replacement that can be easily conceived by those skilled in the art within the technical scope of the present invention is All should be covered by the scope of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

Claim  A method for measuring quality of media transmission, characterized in that it comprises:  Receiving a data stream, calculating at least one rate value according to the feature information of the TS packet in the data stream; acquiring a maximum rate value among the calculated rate values;  Calculating a critical rate value based on the feature information of the TS packet that calculates the maximum rate value; obtaining the calculated rate value between the maximum rate value and the critical rate value, according to the maximum rate value and the critical value The rate value between the rate values determines the media ideal rate.  The method for applying media transmission quality measurement according to claim 1, wherein the feature information of the TS packet includes: a number of TS packets between two TS packets carrying PCR information, and the PCR information for two TS packets.  The method for applying the media transmission quality measurement according to claim 2, wherein the calculating the critical rate value based on the feature information of the TS packet that calculates the maximum rate value comprises: calculating the Determining the number of TS packets of the maximum rate value by one, and obtaining a corresponding number of bytes; determining, according to the PCR information, a time used for calculating the maximum rate value;  Dividing the number of bytes by the time yields a critical rate value.  The method for applying media transmission quality measurement according to claim 1, wherein the determining the media ideal rate according to the rate value between the maximum rate value and the critical rate value comprises: calculating a maximum rate value and The frequency at which all rate values occur within the critical rate value interval;  The highest frequency rate value will appear as the media ideal rate.  The method for applying media transmission quality measurement according to claim 1, wherein the determining the media ideal rate according to the rate value between the maximum rate value and the critical rate value comprises: calculating a maximum rate value and The average of all data flow rate values within the critical rate value interval; the average is taken as the media ideal rate. The method for applying media transmission quality measurement according to any one of claims 1 to 5, characterized in that the method further comprises: calculating a delay parameter according to the media ideal rate, and/or according to the medium The ideal rate calculates the media packet loss rate. The method for applying the media transmission quality measurement according to claim 6, wherein the calculating the delay parameter according to the media ideal rate comprises:  The two packet virtual cache height values are calculated each time a data is received in the calculation period; the difference between the maximum and minimum values of all the virtual cache height values calculated in the calculation period is divided by the media ideal rate to obtain a delay parameter.  8. The method for applying media transmission quality measurement according to claim 7, wherein the calculating two virtual cache height values each time a data is received in the calculation period comprises: receiving the data stream Find the number of bytes of the packet that was received before the current received packet; count the number of bytes of the currently received packet;  Record the time taken from the start of the measurement to the current reception of the data packet;  Substituting the number of received bytes minus the product of the ideal rate of the medium and the recorded time to obtain a virtual cache height value;  The sum of the number of received bytes and the number of bytes of the received packet minus the sum of the media ideal rate and the recorded time yields another virtual cache height value.  The method for applying media transmission quality measurement according to claim 6, wherein the calculating the media packet loss rate according to the media ideal rate comprises:  Count the number of bytes actually received by the TS packet during the current calculation period;  Calculating the number of bytes of the TS packet that should be received in the current calculation period according to the ideal rate of the medium; calculating the media packet loss rate according to the number of TS packets that should be received and the number of TS packets actually received. The method for applying media transmission quality measurement according to claim 9, wherein the calculating the number of bytes that should receive the TS packet in the current calculation period according to the media ideal rate comprises: acquiring the received data PCR value of the TS packet with PCR information in the stream;  Determine whether the calculation cycle is over;  At the end of the calculation period, determining the earliest acquired PCR value and the last acquired PCR value in the calculation period; Calculating the time span between the earliest acquired PCR value and the last acquired PCR value; Calculates the number of bytes that should be received based on the time span and the media ideal rate.  11. A device for measuring media transmission quality, characterized in that it comprises:  a prediction unit, configured to receive a data stream, and calculate at least one rate value according to the feature information of the TS packet in the data stream;  An obtaining unit, configured to obtain a maximum rate value among the calculated rate values;  a calculating unit, configured to calculate a critical rate value based on the feature information of the TS packet that calculates the maximum rate value;  And a determining unit, configured to obtain the calculated rate value between the maximum rate value and the critical rate value, and determine a media ideal rate according to the rate value between the maximum rate value and the critical rate value.  The device for applying the quality measurement of the media transmission according to claim 11, wherein the feature information of the TS packet includes: the number of TS packets between two TS packets carrying PCR information, and The PCR information of the two TS packets is described.  The apparatus for measuring media transmission quality according to claim 12, wherein the calculating unit comprises:  a pre-processing module, configured to reduce the number of TS packets that calculate the maximum rate value by one, and obtain a corresponding number of bytes; and determine, according to the PCR information, a time used to calculate a maximum rate value;  A divide module is configured to divide the number of bytes by the time to derive a critical rate value.  The device for measuring media transmission quality according to claim 1, wherein the determining unit comprises:  a statistics module, configured to count the frequency of occurrence of all rate values in the interval between the maximum rate value and the critical rate value;  The processing module is configured to use the highest frequency rate value as the media ideal rate.  The device for measuring media transmission quality according to claim 1, wherein the determining unit comprises: a calculation module, configured to calculate an average value of all data flow rate values in the interval between the maximum rate value and the critical rate value; And a processing module, configured to use the average value as a media ideal rate.  The device for measuring media transmission quality according to any one of claims 1 to 15, wherein the device further comprises:  The delay parameter calculation unit is configured to calculate a delay parameter according to the media ideal rate, and/or a media packet loss rate calculation unit, configured to calculate a media packet loss rate according to the media ideal rate.  The device for measuring media transmission quality according to claim 16, wherein the delay parameter calculation unit comprises:  a delay parameter pre-processing module, configured to calculate two packet virtual cache height values each time a data is received in a calculation period;  The delay parameter calculation module is configured to obtain a delay parameter by dividing the difference between the maximum value and the minimum value of all the virtual cache height values calculated in the calculation period by the media ideal rate.  The device for applying the quality measurement of the media transmission according to claim 17, wherein the delay parameter pre-processing module comprises:  a lookup submodule, configured to find, in the received data stream, the number of data packets received before the current received data packet;  a statistics submodule, configured to count the number of bytes of the currently received data packet;  a recording submodule, configured to record a time taken from the start of the measurement to the current reception of the data packet; the first calculation submodule, configured to subtract the product of the received number of bytes from the media ideal rate and the recorded time to obtain a virtual cache height value ;  And a second calculation submodule, configured to subtract the sum of the media ideal rate and the recorded time from the sum of the number of received bytes and the number of bytes of the received packet to obtain another virtual cache height value.  The device for measuring media transmission quality according to claim 16, wherein the media packet loss rate calculation unit comprises: a byte statistics module, configured to count the number of bytes of the TS packet actually received in the current calculation period; and a byte calculation module, configured to calculate, according to the media ideal rate, the number of bytes that should receive the TS packet in the current calculation period; The media packet loss rate calculation module is configured to calculate a media packet loss rate according to the number of TS packets that should be received and the number of actually received TS packets.  The apparatus for measuring media transmission quality according to claim 19, wherein the byte calculation module comprises:  Obtaining a sub-module, configured to obtain a PCR value of a TS packet having PCR information in the received data stream; and determining a sub-module, configured to determine whether the calculation period ends;  Determining a sub-module, configured to determine, at the end of the calculation period, the earliest acquired PCR value and the last acquired PCR value in the calculation period;  a first calculation sub-module, configured to calculate a time span between the earliest acquired PCR value and the last acquired PCR value;  A second calculation sub-module for calculating the number of bytes that should be received based on the time span and the media ideal rate.