CN102263556A - Sampling rate judgment method and device - Google Patents
Sampling rate judgment method and device Download PDFInfo
- Publication number
- CN102263556A CN102263556A CN2010101928796A CN201010192879A CN102263556A CN 102263556 A CN102263556 A CN 102263556A CN 2010101928796 A CN2010101928796 A CN 2010101928796A CN 201010192879 A CN201010192879 A CN 201010192879A CN 102263556 A CN102263556 A CN 102263556A
- Authority
- CN
- China
- Prior art keywords
- sample rate
- weighted average
- multiple value
- frequency
- value
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
Images
Landscapes
- Synchronisation In Digital Transmission Systems (AREA)
Abstract
The invention provides a sampling rate judgment method and device, used for receiving input signals of a Sony/Philips digital interface (SPDIF). The sampling rate judgment method comprises the following steps of: solving a plurality of multiple values of biphasic clock frequency and system frequency in the input signals, and calculating a first weighted average and a second weighted average according to a first filtering range, a second filtering range and the multiple values; and when a first difference value is larger than a second difference value, setting a sampling rate to be a first sampling rate, and otherwise setting the sampling rate to be a second sampling rate, wherein the first difference value and the second difference value are calculated according to the first weighted average, the second weighted average and a frequency threshold value. According to the invention, the sampling rate of the input signals can be judged quickly according to the weighted averages generated through filtering range adjustment, therefore, the probability of erroneous judgment can be reduced and the space of a memory can be saved.
Description
Technical field
The invention relates to a kind of Sony/philips digital interface (Sony/Philips DigitalInterface, the technology of sample rate SPDIF), and, and can reduce the erroneous judgement probability and save memory particularly relevant for the technology of a kind of weighted average according to filter area with rapid judgement input signal sample rate.
Background technology
Sony/philips digital interface (Sony/Philips Digital Interface Format, be called for short SPDIF) be a kind of Digital Audio Transmission interface, and generally utilize optical fiber and coaxial cable to transmit accuracy and synchronism to guarantee data, can make the output result have high fidelity (fidelity).Therefore, SPDIF is widely used in supporting in the DVD player and CD Player of Digital Theater System (Digital TheaterSystem is called for short DTS) or Dolby Digital (Dolby digital).
In addition, SPDIF adopts two-phase symbolic coding (Bi-phase Mark Code is called for short BMC), thereby sample frequency and its sample information are mixed transmission.Therefore, its transmission ends and receiving terminal only need a data wire just data can be transmitted and receive, and the receiving terminal of SPDIF just must separate sample frequency from input signal, thereby correctly input signal are sampled.The SPDIF form of standard can be sampled to the input signal of four kinds of sample rates, these sample rates are respectively 32KHz, 44.1KHz, 48KHz and 96KHz, wherein, 44.1KHz (digitized audio samples that is usually used in CD) is comparatively approaching with both sample rates of 48KHz (digitized audio samples that is usually used in DVD), makes that the erroneous judgement probability of receiving terminal when judging these two sample rates of SPDIF is higher.
Thereby in this measure one example explanation, meeting in the input signal of SPDIF each sampled result all transmits with 32 (32-bit), and comprise left and right acoustic channels information, and each all need sample twice, so the diphasic clock frequency of 44.1KHz and 48KHz (bi-phase clockfrequency) BCF
44.1Khz, BCF
48KhzJust shown in equation (1) and (2):
BCF
44.1Khz＝44.1Khz×32×2×2＝5.6448Mhz.......(1)
BCF
48Khz＝48Khz×32×2×2＝6.144Mhz.............(2)
When judging sample rate, the input signal of carrying 44.1KHz and 48KHz can be according to diphasic clock frequency BCF
44.1Khz, BCF
48KhzJudge.But during the influencing of factors such as the device quality discrepancy that is subjected to clock jitter (clock jitter), transmission ends when input signal and sampling accuracy, diphasic clock frequency BCF is difficult to differentiate when just too approaching drift because of its both numerical value, makes that the erroneous judgement probability of receiving terminal when judging these two sample rates of SPDIF is higher.If want to reduce the erroneous judgement probability, just need increase the judgement number of times of sample rate, utilize repeatedly sampled result on average correctly determining sample rate, but also therefore increased memory span, also improved the judgement required time.
Summary of the invention
The invention provides a kind of method of judging sample rate, this method receives the input signal of Sony/philips digital interface (SPDIF), and judge the sample rate of input signal rapidly according to the weighted average that filter area is adjusted, thus the erroneous judgement probability reduced, and save and judge required memory.
In another viewpoint, the invention provides a kind of device of judging sample rate, this device receives the input signal of Sony/philips digital interface, and utilizes filter area to adjust weighted average, with rapid judgement sample rate, and can reduce the erroneous judgement probability and save memory.
The present invention proposes a kind of method of judging sample rate, and it is used to receive the input signal of Sony/philips digital interface.This method comprises the following steps.Ask for diphasic clock frequency in the input signal and a plurality of multiple value between the system frequency, and foundation first filter area is adjusted first weighting sequence, thereby foundation first weighting sequence and above-mentioned multiple value are calculated and are tried to achieve first weighted average, then adjust second weighting sequence, thereby try to achieve second weighted average according to second weighting sequence and multiple value according to second filter area.Afterwards, when first difference during greater than second difference, sample rate is set at first sample rate, otherwise this sample rate is set at second sample rate, wherein first difference is calculated according to first weighted average and frequency threshold and is tried to achieve, and second difference is then calculated according to second weighted average and frequency threshold and tried to achieve.
In one embodiment of this invention, the first above-mentioned filter area is greater than the high pass threshold value, and second filter area is then less than the low pass threshold value.
In one embodiment of this invention, adjust first weighting sequence according to first filter area and comprise the following steps according to the step that first weighting sequence and multiple value calculate first weighted average.Removal is less than or equal to the multiple value of high pass threshold value, then calculates the not arithmetic average of removed multiple value, thereby obtains first weighted average.In addition, adjust second weighting sequence according to second filter area, and comprise follow procedure according to the step that second weighting sequence and multiple value calculate second weighted average.Removal is then calculated the not arithmetic average of removed multiple value, thereby is obtained second weighted average more than or equal to the multiple value of low pass threshold value.
In one embodiment of this invention, the step of asking for multiple value comprises follow procedure.Obtain a plurality of diphasic clock frequencies that are positioned at different time points according to input signal, and with system frequency divided by above-mentioned diphasic clock frequency, to obtain a plurality of multiple value.
In one embodiment of this invention, the first above-mentioned difference is the absolute value that first weighted average deduct frequency threshold, and second difference then is the absolute value that second weighted average deduct frequency threshold.
In one embodiment of this invention, the method for above-mentioned judgement sample rate also can comprise the following steps, adjusts or change first filter area, second filter area and frequency threshold with the foundation system frequency.
From another angle, the present invention proposes a kind of device of judging sample rate, and it receives the input signal of Sony/philips digital interface.The device of judging sample rate comprises the frequency sampling unit, filters computing unit and judging unit.The frequency sampling unit is in order to ask for diphasic clock frequency in the input signal and a plurality of multiple value between the system frequency.Filter computing unit and be coupled to the frequency sampling unit, it adjusts first weighting sequence according to first filter area, and calculates first weighted average according to first weighting sequence and multiple value.Filter computing unit and also adjust second weighting sequence, and try to achieve second weighted average according to second weighting sequence and multiple value according to second filter area.Judging unit is coupled to the filtration computing unit, and when first difference during greater than second difference, judging unit is set at first sample rate with this sample rate, otherwise judging unit is set at second sample rate with sample rate, wherein first difference is tried to achieve according to first weighted average and frequency threshold, and second difference is then tried to achieve according to second weighted average and frequency threshold.
In one embodiment of this invention, the first above-mentioned filter area is greater than the high pass threshold value, and second filter area is then less than the low pass threshold value.
In one embodiment of this invention, above-mentioned filtration computing unit comprises high pass computing unit and low pass computing unit.The high pass computing unit is less than or equal to the multiple value of high pass threshold value in order to removal, and calculates the not arithmetic average of removed multiple value, thereby obtains first weighted average.The low pass computing unit is in order to removing the multiple value more than or equal to the low pass threshold value, and calculates the not arithmetic average of removed multiple value, thereby obtains second weighted average.
In one embodiment of this invention, the device of above-mentioned judgement sample rate also can comprise storage element, and it is coupled to the frequency sampling unit to receive and to store multiple value.
In one embodiment of this invention, the device of above-mentioned judgement sample rate also can comprise the coefficient settings unit, and it is coupled to the frequency sampling unit and filters computing unit.First filter area, second filter area and frequency threshold are adjusted or changed in the coefficient settings unit in order to the foundation system frequency.
Based on above-mentioned, embodiments of the invention are asked for a plurality of multiple value according to the diphasic clock frequency of different time, and adjust weighting sequence according to filter area, thereby utilize weighting sequence that these multiple value are calculated first weighted average and second weighted average.Then, just can judge the sample rate tendency of input signal, thereby reduce the erroneous judgement probability, and can judge rapidly that sample rate is to save required memory by first weighted average, second weighted average and frequency threshold.
For above-mentioned feature and advantage of the present invention can be become apparent, embodiment cited below particularly, and cooperate appended graphic being described in detail below.
Description of drawings
Fig. 1 is that an embodiment illustrates the method schematic diagram of judging sample rate.
Fig. 2 is a kind of device calcspar of judging sample rate according to one embodiment of the invention.
Fig. 3 is a kind of method flow diagram of judging sample rate according to one embodiment of the invention.
Fig. 4 is a schematic diagram of setting weighting sequence according to one embodiment of the invention explanation according to filter area.
Fig. 5 is a kind of device calcspar of judging sample rate according to another embodiment of the present invention.
Fig. 6 a is according to the curve chart of one embodiment of the invention explanation according to the erroneous judgement probability that different buffer size produced.
Fig. 6 b is the chart with the information dataization of Fig. 6 a.
The main element symbol description
20,50: the device of judging sample rate
210: the frequency sampling unit
220: the sampling by filtration unit
230: judging unit
510: coefficient decision unit
520: storage element
530: the high pass computing unit
540: the low pass computing unit
IS: the input signal that meets SPDIF
S310～S360: step
SR: sample rate
SF: system frequency
ThF: frequency threshold
ThH: high pass threshold value
ThL: low pass threshold value
L1, L2: curve
Embodiment
Now will the example of described one exemplary embodiment be described in the accompanying drawings in detail with reference to one exemplary embodiment of the present invention.In addition, all possibility parts, the identical or similar portions of element/member/symbology of use same numeral in graphic and execution mode.
Please refer to Fig. 1, Fig. 1 is the method schematic diagram that an embodiment illustrates the sample rate SR of the input signal IS that judges Sony/philips digital interface (SPDIF).Be set at 108Mhz at this system frequency SF with present embodiment, and sample rate 48Khz and the pairing diphasic clock frequency of 44.1Khz BCF
48KhzWith BCF
44.1KhzThen about slightly 6.144Mhz and 5.6448Mhz (shown in equation (1) and (2)).Thus, system frequency SF is divided by diphasic clock frequency BCF
48KhzWith BCF
44.1KhzThe merchant who is produced (also for the described multiple value of present embodiment) as equation (3) with as described in (4):
And according to device-restrictive, multiple value only can be noted down integer value, so present embodiment is set at 19 with frequency threshold thF, because of 19 being integer value between 17.57812 to 19.13256.In present embodiment, when the arithmetic average of the multiple value of asking for during, just sample rate SR can be judged as 44.1Khz greater than 19 (frequency threshold thF), then setting sample rate SR when opposite is 48Khz.
Please continue to consult Fig. 1, because the cause influences such as device quality discrepancy of clock jitter, transmission ends, these multiple value when sample rate is 48Khz most of drift in 17～20 integer range, and in the integer range of the also rough drift of the multiple value that when sample rate is 44.1Khz, is produced 18～21, but can exceed above-mentioned integer range once in a while.Because in the past determination methods utilizes arithmetic mean as account form, therefore when the multiple value of sampling more after a little while, part exceeds the multiple value of integer range will be bigger to the influence of arithmetic mean value, thereby cause erroneous judgement.
For example with what describe in detail, as shown in table 1, IS has the sample rate of 44.1Khz at this hypothesis input signal at this, thereby and produces 10 multiple value.
Table 1
The arithmetic average of the multiple value of table 1 is 18.9.Because 18.9 (arithmetic averages of multiple value) less than 19 (frequency threshold thF), therefore just are set at 48Khz with sample rate SR, but the sample rate of original input signal IS is 44.1Khz, thereby cause erroneous judgement.The settling mode of this kind erroneous judgement then be obtain more multiple value and get its mean value so that its mean value greater than 19 (frequency threshold thF) correct decision, but can prolong judgement time and increase required memory.
Therefore, propose an embodiment according to the invention at this, Fig. 2 is a kind of device 20 calcspars of judging sample rate according to one embodiment of the invention.Please refer to Fig. 1, judge that the device 20 of sample rate receives the input signal IS that meets Sony/philips digital interface, thereby judge sample rate SR.The device 20 of judging sample rate comprises frequency sampling unit 210, filters computing unit 220 and judging unit 230.Frequency sampling unit 210 is in order to ask for diphasic clock frequency BCF among the input signal IS and a plurality of multiple value between the system frequency SF.Filter computing unit 220 and be coupled to frequency sampling unit 210, it adjusts first weighting sequence according to first filter area (present embodiment to be example greater than high pass threshold value thH), and calculates first weighted average according to first weighting sequence and multiple value.Filter computing unit 220 and also can adjust second weighting sequence, and try to achieve second weighted average according to second weighting sequence and multiple value according to second filter area (present embodiment to be example) less than low pass threshold value thL.
Please continue with reference to Fig. 2, judging unit 230 is coupled to and filters computing unit 220, tries to achieve first difference in order to calculate according to first weighted average and frequency threshold thF, and tries to achieve second difference according to second weighted average and frequency threshold thF with calculating.As the first difference D1 during greater than the second difference D2, judging unit 230 is set at first sample rate (present embodiment is example with 44.1Khz) with sample rate SR, otherwise judging unit 130 just is set at sample rate SR second sample rate (present embodiment is example with 48Khz).
In order to cause those skilled in the art can understand the present invention more, describe in detail at this process step according to the embodiment of the invention.Fig. 3 is a kind of method flow diagram of judging sample rate according to one embodiment of the invention, please be simultaneously with reference to Fig. 2 and Fig. 3, the embodiment of the invention at first enters step S310, frequency sampling unit 210 receives the input signal IS that meets Sony/philips digital interface, thereby obtain the diphasic clock frequency BCF of different time points among the input signal IS, again these diphasic clock frequency BCF and system frequency SF are divided by in the hope of a plurality of multiple value.Asking for 10 multiple value as an example, and hypothesis input signal IS has the sample rate of 44.1Khz in the present embodiment, and wherein frequency sampling unit 210 multiple value of being tried to achieve is shown in above-mentioned table 1.
Then, enter step S320, filter computing unit 220 and utilize first filter area (present embodiment to be example) and second filter area (present embodiment to be example) to adjust first weighting sequence and second weighting sequence respectively, and foundation first weighting sequence, second weighting sequence and above-mentioned multiple value calculate first weighted average and second weighted average respectively less than low pass threshold value thL greater than high pass threshold value thH.In present embodiment, according to system frequency SF high pass threshold value thH is set at 17 at this, and high pass threshold value thL is set at 21, and together with reference to Fig. 4, Fig. 4 is a schematic diagram of setting weighting sequence according to one embodiment of the invention explanation according to filter area.As shown in Figure 4, first weighting sequence in the present embodiment and second weighting sequence all have the weighted value of corresponding each multiple value, use the present embodiment person and can look its design requirement and decide how to be provided with and be positioned at the inside and outside weighted value of filter area.In present embodiment, the pairing weighted value of multiple value that filtration computing unit 220 will be positioned at first filter area outer (that is being less than or equal to 17) is set at 0, thereby all multiple value that are less than or equal to 17 are removed, but the present invention should be as limit.In other embodiment, filter computing unit 220 and also can reduce the pairing weighted value of multiple value (for example being reduced to 0.1) that is positioned at outside first filter area from 1, thereby reduce the influence that is positioned at the outer multiple value of filter area, perhaps increase the pairing weighted value of multiple value (for example increasing to 1.5) that is positioned at first filter area from 1, to strengthen the influence of the multiple value in the filter area, do not repeat them here.
Please continue with reference to Fig. 4, the pairing weighted value of multiple value that filtration computing unit 220 will be positioned at first filter area outer (that is being less than or equal to 17) is set at 0, and the pairing weighted value of multiple value that will be positioned at first filter area (and greater than 17) is set at 1, form the effect of similar high pass filter thus, all multiple value that are less than or equal to 17 are removed, and the arrangement of the multiple value of table 1 is as shown in table 2, and represent the multiple value removed with strikethrough.
Table 2
Thus, just the multiple value of will not removing according to table 2 counts on average, also is about to that all multiple value of not removing add the General Logistics Department divided by 8 in the table 2, in the hope of the first weighted average N
Hp(the first weighted average N of present embodiment
HpRoughly equal 19.375).
In like manner, the pairing weighted value of multiple value that filtration computing unit 220 also will be positioned at second filter area outer (that is more than or equal to 21) is set at 0, and the pairing weighted value of multiple value that will be positioned at first filter area (and less than 21) is set at 1, form the effect of similar low pass filter thus, all are removed more than or equal to 21 multiple value, and the arrangement of the multiple value of table 1 is as shown in table 3, represent the multiple value of having removed with strikethrough.
Table 3
Thus, just the multiple value of will not removing according to table 3 counts on average, also is about to that all multiple value of not removing add the General Logistics Department divided by 9 in the table 3, in the hope of the second weighted average N
Lp(the second weighted average N of present embodiment
LpRoughly equal 18.66667).
Please continue with reference to Fig. 2 and Fig. 3, calculate the first weighted average N when filtering computing unit 220
HpWith the second weighted average N
LpAfter, just entering step S330, judging unit 230 is according to the first weighted average N
HpCalculate the first difference D1 with frequency threshold thF, also can be according to the second weighted average N
LpCalculate the second difference D2 with frequency threshold thF, its account form is shown in equation (5) and (6):
D1＝|N
hp-thF|＝|19.375-19|＝0.375..............(5)
D2＝|N
lp-thF|＝|18.66667-19|＝0.33333......(6)
That is first difference D1 be the first weighted average N
HpDeduct the absolute value of frequency threshold thF, second difference then is the second weighted average N
LpDeduct the absolute value of frequency threshold thF.Then, whether judging unit 230 judges the first difference D1 greater than the second difference D2 in step S340, thereby the sample rate tendency of judging these multiple value is greater than or less than frequency threshold thF.Because the first difference D1 (0.375) of present embodiment is greater than the second difference D2 (0.33333), just enter step S350, judging unit 230 is set at 44.1Khz with sample rate SR, that is be used for the sample rate of CD audio frequency, thereby present embodiment utilizes first weighted average, second weighted average and the frequency threshold thF correct sample rate SR that forms a prompt judgement out, and reduce the erroneous judgement probability, also can reduce and judge the required memory of sample rate SR.
In addition, enumerate another example with the explanation embodiment of the invention at this, and simultaneously with reference to Fig. 2 and Fig. 3.At first enter step S310, frequency sampling unit 210 receives and meets the input signal IS of Sony/philips digital interface, thereby asks for a plurality of multiple value, at this to ask for 10 multiple value as an example, as shown in table 4, IS has the sample rate of 48Khz at this hypothesis input signal.
Table 4
The arithmetic average of the multiple value of above-mentioned table 4 is 19.1.Because 19.1 (arithmetic averages of multiple value) greater than 19 (frequency threshold thF), if will be set at 44.1Khz to sample rate SR according to judgment mode in the past, thereby cause erroneous judgement.
Just enter step S320 after obtaining enough multiple value, filtering computing unit 220 removes the multiple value that all are less than or equal to 17 (that is high pass threshold value thH) by first weighting sequence of Fig. 4, thereby the arrangement of the multiple value of table 4 is as shown in table 5, and strikethrough is wherein represented the multiple value removed.
Table 5
Thus, just the multiple value of will not removing according to table 5 counts on average, also is about to that all multiple value of not removing add the General Logistics Department divided by 9 in the table 5, in the hope of the first weighted average N
Hp(the first weighted average N of present embodiment
HpRoughly equal 19.33333).
And, filtering computing unit 220 and also all are removed more than or equal to the multiple value of 21 (that is low pass threshold value thL), thereby the multiple value of table 4 is put in order as shown in table 6 by second weighting sequence of Fig. 4, strikethrough is wherein represented the multiple value removed.
Table 6
Thus, just the multiple value of will not removing according to table 6 counts on average, also is about to that all multiple value of not removing add the General Logistics Department divided by 8 in the table 6, in the hope of the second weighted average N
Lp(the second weighted average N of present embodiment
LpRoughly equal 18.625).
In step S330, judging unit 230 is tried to achieve the first difference D1 and the second difference D2 according to equation (7) and (8) with calculating:
D1＝|N
hp-thF|＝|19.33333-19|＝0.33333......(7)
D2＝|N
lp-thF|＝|18.625-19|＝0.375..............(8)
Then, because the first difference D1 (0.33333) is less than the second difference D2 (0.375), therefore judging unit 230 enters step S360 from step S340, and sample rate SR is set at 48Khz, that is be used for the sample rate of DVD digital audio, and other thin portion flow processs of present embodiment have been included in the various embodiments described above, so do not repeat them here.
The filtration computing unit 220 of the foregoing description can calculate the multiple value number of reception by counter, thereby and utilize the totalling device that filters in the computing unit 220 to calculate and try to achieve first weighted average and second weighted average, therefore judge that the device 20 of sample rate SR can not need be equipped with storage element, but can be not as limit.Please refer to Fig. 5, Fig. 5 is a kind of device 50 calcspars of judging sample rate according to another embodiment of the present invention.Present embodiment is similar to the aforementioned embodiment, so same action mode and explanation repeat no more.Its difference is that the device 50 of judging sample rate can comprise storage element 520, and it is coupled to frequency sampling unit 210 and filters computing unit 220.Storage element 520 is tried to achieve first weighted average and second weighted average in order to receive and to store multiple value so that filtration computing unit 220 can calculate according to the multiple value in the storage element 520.
Please continue with reference to Fig. 5, judge that the device 50 of sample rate also can comprise coefficient settings unit 510, it is coupled to frequency sampling unit 210, filters computing unit 220 and judging unit 230.Coefficient settings unit 510 is sent to frequency sampling unit 210 with system frequency SF, thereby asks for multiple value according to input signal IS.If the device 50 of judging sample rate is voluntarily during altering system frequency SF, frequency threshold thF in first filter area, second filter area and the judging unit that filters in the computing unit be adjusted or be changed in coefficient settings unit 510 also can according to system frequency SF.
On the other hand, the filtration computing unit 220 of present embodiment also can comprise high pass computing unit 530 and low pass computing unit 540.High pass computing unit 530 is adjusted first weighting sequence according to first filter area (at this being example greater than high pass threshold value thH), and calculates the first weighted average N according to first weighting sequence and multiple value
Hp540 foundation second filter areas of low pass computing unit (at this being example less than low pass threshold value thL) are adjusted second weighting sequence, and try to achieve the second weighted average N according to second weighting sequence and multiple value
Lp
In addition, an embodiment is proposed with the evidence embodiment of the invention at this, its correct sample rate SR that can form a prompt judgement out, and the use that can reduce wrong probability and reduce memory, please refer to Fig. 6 a and Fig. 6 b, Fig. 6 a is according to the curve chart of one embodiment of the invention explanation according to the erroneous judgement probability that different buffer size produced, and Fig. 6 b is with the information dataization of Fig. 6 a.Fig. 6 a transverse axis is depicted as buffer size in the storage element 520, with byte (byte) is unit, Fig. 6 a longitudinal axis then is the erroneous judgement probability according to present embodiment and existing determination methods, number of times (that is PPM) with per 1,000,000 erroneous judgements is a unit, the block curve L1 of Fig. 6 a is the experimental result of present embodiment, and the dashed curve L2 of Fig. 6 a then is the experimental result of determination methods in the past.
See also Fig. 6 a and Fig. 6 b,, just can judge sample rate SR exactly, but determination methods in the past needs 100 bytes could judge sample rate SR exactly when the buffering area of storage element 520 utilizes 40 bytes when judging the memory of sample rate SR.In addition, the erroneous judgement probability of block curve L1 all is less than dashed curve L2 in the buffering areas of every kind of different sizes, because of can think present embodiment compared with the time less of in the past the required judgement of determination methods, to judge the lower and required memory of probability by accident less.
In sum, embodiments of the invention are asked for a plurality of multiple value according to the diphasic clock frequency of different time, and adjust weighting sequence according to filter area, thereby utilize weighting sequence that these multiple value are calculated first weighted average and second weighted average.Then, judge the sample rate tendency of input signal by first weighted average, second weighted average and frequency threshold.When the difference of first weighted average and frequency threshold during, represent these multiple value tendencies greater than frequency threshold, and sample rate can be set at 44.1Khz greater than the difference of second weighted average and frequency threshold.Opposite in this, when the difference of first weighted average and frequency threshold during less than the difference of second weighted average and frequency threshold, represent these multiple value tendencies less than frequency threshold, just sample rate is set at 48Khz, thereby reduce the erroneous judgement probability, and can judge sample rate rapidly, judge required memory to save.
Though the present invention discloses as above with embodiment; right its is not in order to qualification the present invention, any those skilled in the art, without departing from the spirit and scope of the present invention; when doing a little change and retouching, so protection scope of the present invention is as the criterion when looking claims person of defining.
Claims (12)
1. method of judging sample rate is used to judge the sample rate of the input signal of Sony/philips digital interface, and this method comprises:
Ask for diphasic clock frequency in this input signal and a plurality of multiple value between the system frequency;
Adjust first weighting sequence according to first filter area, and calculate first weighted average according to this first weighting sequence and described multiple value, and adjust second weighting sequence according to second filter area, and calculate second weighted average according to this second weighting sequence and described multiple value; And
When first difference during greater than second difference, this sample rate is set at first sample rate, otherwise this sample rate is set at second sample rate, wherein this first difference is tried to achieve according to these first weighted average and frequency threshold, and this second difference is tried to achieve according to these second weighted average and this frequency threshold.
2. the method for judgement sample rate according to claim 1, wherein this first filter area is greater than the high pass threshold value, and this second filter area is less than the low pass threshold value.
3. the method for judgement sample rate according to claim 2, adjust this first weighting sequence and comprise according to this first filter area according to the step that this first weighting sequence and described multiple value calculate these first weighted average:
Removal is less than or equal to the described multiple value of this high pass threshold value; And
Calculate the not arithmetic average of removed described multiple value, obtaining this first weighted average,
Adjust this second weighting sequence and comprise according to this second filter area according to the step that this second weighting sequence and described multiple value calculate these second weighted average:
Removal is more than or equal to the described multiple value of this low pass threshold value; And
Calculate the not arithmetic average of removed described multiple value, to obtain this second weighted average.
4. the method for judgement sample rate according to claim 1, wherein this first sample rate is the CD audio sample rate, this second sample rate is a DVD digitized audio samples rate.
5. the method for judgement sample rate according to claim 1, the step of asking for described multiple value comprises:
Obtain the described diphasic clock frequency of different time according to this input signal; And
With this system frequency divided by described diphasic clock frequency, to obtain described multiple value.
6. the method for judgement sample rate according to claim 1, wherein this first difference is the absolute value that these first weighted average deduct this frequency threshold, this second difference deducts the absolute value of this frequency threshold for these second weighted average.
7. the method for judgement sample rate according to claim 1 also comprises:
According to this system frequency adjustment or change this first filter area, this second filter area and this frequency threshold.
8. device of judging sample rate is used to judge the sample rate of the input signal of Sony/philips digital interface, and this device comprises:
The frequency sampling unit is in order to ask for diphasic clock frequency in this input signal and a plurality of multiple value between the system frequency;
Filter computing unit, be coupled to this frequency sampling unit, in order to adjust first weighting sequence according to first filter area, and calculate first weighted average according to this first weighting sequence and described multiple value, and adjust second weighting sequence according to second filter area, and try to achieve second weighted average according to this second weighting sequence and described multiple value; And
Judging unit, be coupled to this filtration computing unit, when first difference during greater than second difference, this judging unit is set at first sample rate with this sample rate, otherwise this sample rate is set at second sample rate, wherein this first difference is tried to achieve according to these first weighted average and frequency threshold, and this second difference is tried to achieve according to these second weighted average and this frequency threshold.
9. the method for judgement sample rate according to claim 8, wherein this first filter area is greater than the high pass threshold value, and this second filter area is less than the low pass threshold value.
10. the device of judgement sample rate according to claim 9, wherein this filtration computing unit comprises:
The high pass computing unit is less than or equal to the described multiple value of this high pass threshold value in order to removal, and calculates the not arithmetic average of removed described multiple value, to obtain this first weighted average; And
The low pass computing unit in order to the described multiple value of removal more than or equal to this low pass threshold value, and calculates the not arithmetic average of removed described multiple value, to obtain this second weighted average.
11. the device of judgement sample rate according to claim 8 also comprises:
Storage element is coupled to this frequency sampling unit and this judging unit, in order to receive and to store described multiple value.
12. the device of judgement sample rate according to claim 8 also comprises:
The coefficient settings unit is coupled to this frequency sampling unit and this filtration computing unit, in order to adjust or to change this first filter area, this second filter area and this frequency threshold according to this system frequency.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2010101928796A CN102263556A (en) | 2010-05-28 | 2010-05-28 | Sampling rate judgment method and device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2010101928796A CN102263556A (en) | 2010-05-28 | 2010-05-28 | Sampling rate judgment method and device |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN102263556A true CN102263556A (en) | 2011-11-30 |
Family
ID=45010046
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN2010101928796A Pending CN102263556A (en) | 2010-05-28 | 2010-05-28 | Sampling rate judgment method and device |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN102263556A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107423433A (en) * | 2017-08-03 | 2017-12-01 | 聚好看科技股份有限公司 | A kind of data sampling rate control method and device |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP1216604B1 (en) * | 1999-10-01 | 2004-03-10 | France Telecom | Method for continuously controlling the quality of distributed digital sounds |
| CN101080870A (en) * | 2004-11-12 | 2007-11-28 | 模拟设备股份有限公司 | Sample rate converter for reducing the sampling frequency of a signal by a fraction |
| CN101645273A (en) * | 2009-07-10 | 2010-02-10 | 中国科学院声学研究所 | System for estimating and correcting difference in sampling rates and processing method thereof |
-
2010
- 2010-05-28 CN CN2010101928796A patent/CN102263556A/en active Pending
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP1216604B1 (en) * | 1999-10-01 | 2004-03-10 | France Telecom | Method for continuously controlling the quality of distributed digital sounds |
| CN101080870A (en) * | 2004-11-12 | 2007-11-28 | 模拟设备股份有限公司 | Sample rate converter for reducing the sampling frequency of a signal by a fraction |
| CN101645273A (en) * | 2009-07-10 | 2010-02-10 | 中国科学院声学研究所 | System for estimating and correcting difference in sampling rates and processing method thereof |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107423433A (en) * | 2017-08-03 | 2017-12-01 | 聚好看科技股份有限公司 | A kind of data sampling rate control method and device |
| CN107423433B (en) * | 2017-08-03 | 2020-07-10 | 聚好看科技股份有限公司 | Data sampling rate control method and device |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| JP5767462B2 (en) | COMMUNICATION MODE DETECTION METHOD BY RECEIVING DEVICE FOR NEAR RANGE COMMUNICATION | |
| EP2704141A2 (en) | Method and apparatus to remove noise from an input signal in a noisy environment, and method and apparatus to enhance an audio signal in a noisy environment | |
| CN104167209A (en) | Method and device for detecting audio distortion | |
| JP3981589B2 (en) | Time slot generator in home network system | |
| EP0735709B1 (en) | Synchronizing circuit for use in a digital audio signal compressing/expanding system | |
| JP2009303178A (en) | Data receiver, method of receiving data, and data receiving program | |
| CN102263556A (en) | Sampling rate judgment method and device | |
| JP4847466B2 (en) | Apparatus and method for determining arrival time of a reception sequence | |
| CN104835500B (en) | The method and its device that a kind of audio-frequency information obtains | |
| TWI384460B (en) | Method for determining sampling rate and device therefor | |
| US7921147B2 (en) | Filtering integrated circuit | |
| CN114238005A (en) | GPIO anti-shake function test method, system, device and chip | |
| CN105760800A (en) | Data decoding circuit and data decoding method | |
| US8127170B2 (en) | Method and apparatus for audio receiver clock synchronization | |
| JP5023812B2 (en) | Digital audio processing apparatus and digital audio processing program | |
| WO2001043320A3 (en) | Method for decoding digital audio data | |
| JP2856939B2 (en) | Data receiving method | |
| CN114826303B (en) | Data demodulation system based on high priority frame | |
| JP2004037506A (en) | Method for extracting pitch period of voice signal | |
| US11838062B2 (en) | Headset data transmission method, system, and device and computer storage medium | |
| KR100531321B1 (en) | Audio decoding system and audio format detecting method | |
| CN112291696B (en) | Audio chip testing method, storage medium and computer equipment | |
| EP1802010A2 (en) | TII decoder and method for detecting TII | |
| CN101409776B (en) | Method for generating sound clock applied for multimedia interface | |
| EP1926024B1 (en) | Serial communication control system |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| C02 | Deemed withdrawal of patent application after publication (patent law 2001) | ||
| WD01 | Invention patent application deemed withdrawn after publication |
Application publication date: 20111130 |