Sevana AQuA - Audio Quality Analyzer 6.x User Manual
Contents
1. Overall difference between signals spectrums exceeds 15 Corrupted signal spectrum Overall spectral energy distortion approaches 70 55 Difference in signals spectrums is both in positive and getative zones Deviation range should not be out of 5 to 5 range Vibration along the whole spectrum 16 16 54 39 Significant distortion in low frequencies band Energy distortion approaches 26 51 Spectrum vibration in low frequency band 14 39 12 12 Significant distortion in medium frequencies band Energy distortion approaches 36 06 Spectrum distortions are in positive zone Amplification approaches 34 29 Low frequencies below 1000 Hz Medium frequencies from 1000 Hz to 3000 Hz High frequencies are those that are greater than 3000 Hz Distortions in low frequencies are considered when greater than 5 in medium frequencies 10 and in high frequencies 30 Multidirectional spectrum changes vibration is considered when greater than 2 5 in low frequencies 7 in medium frequencies and 15 in high frequencies Unidirectional distortions no matter positive or negative are considered when greater than 5 in low frequencies 10 in medium frequencies and 25 in high frequencies As one can see AQUA did detect the equalization providing quite detailed information on what happened to the test audio The fact that the quality scores in AQUA 6 x and AQuA 5 x may differ is result of our software improvement based2. Command line argument clibf lt file gt eeseseeeessseeesssrersssreresssrtttsssrertssrressssttssseterssstteetssrresesereeensrreeeeee 9 Use initial sound file as source or internal signal generator src file lt fname gt gen lt mode gt folder AE SA AA E AA 9 Set type of weight coefficients ct lt ctype gt sistaisicccesdscavetandsaidestedauedonecsseeahgevandsndiandathcdsandousieesubddsandaacasunass 9 Set name of the file under test tstf lt fname gt wwwwwwmmmmnwanannwwimimawnanawewi mn awanene nima wanawe 9 Set name of report file for folder processing mode frep lt fname gt wwwwwmwananmwmmmanananawewa 10 Set name of the file generated by the speech model dst lt fname gt wwwmemmanaewwmmmanananawewa 10 Generate full speech sounds distribution or synthesized sound sn lt all lt sname gt gt ve 10 Set voice type voit lt female male gt si5ac055 sisceastdsoese eaeaundensd onda iascvnad ewblovea neddsana nsdancaanecanadvancausaweasnnadaadaans 10 Oe CELIO ie OU Ee ct a recta ae seed cata ned R E T A 10 Set quality loss or naturallness qt lt quality naturalness gt eee eeeeneceeeeeeeeeseeeennaeeeeeeeeeeseeennaeeeeeeees 10 Enable indication of codec speed performance power lt on Off gt cccceccecceeeseeeenneeeeeeeeeeeeeetnaeeeeeeees 10 Enable energy normalization enorm lt on Off
3. 847082 Duration distortion Audio stretching corresponds to 14 15 percent Advancing of audio signal activity Signal advances the original by 400 000000 ms Audio signal activity mistiming unsynchronization is 1 34 percent Synchronizing reference and test files using AQuA 6 x In many cases when monitoring voice quality in real life one receives degraded file from the network containing pauses silence before and or after the actual audio Let s consider an example received from one of our customers while doing voice quality monitoring in a mobile network Initial audio is a male voice pronouncing a phrase in English language with the following wave form Copyright Sevana Ltd 2012 Sevana Oy Sevana OU Agricolankatu 11 Rohtlaane 12 00530 Helsinki 76911 Huuru kula Finland Estonia Harjumaa Phone 358 9 2316 4165 Phone 372 53485178 A SEVANA IT solutions amp services This audio is sent over a mobile network and then recorded back but due to delays before the call is established and after hang up degraded file has delays in the beginning and end of the audio Furthermore if one zooms into the silence he will realize that it contains noise According to AQUA algorithms introduction of silence or noise into audio signal leads to quality degradation and taking into account that establishing a test call as well as then detecting disconnect tone may take even a couple of seconds this may significan
4. error src Weights of sound bands error ct Synthesized voice type error voit Incorrect sound duration to synthesize slen Unknown type of quality estimation defined qt Incorrect numbers of links points npnt Incorrect envelope smoothing level miter Incorrect out quality mode ratem Incorrect accuracy value acr Test file name is missing tstf Speech model file name is missing dst Name of synthethized sound is missing sn Codec performance measurement is not set power on off Copyright Sevana Ltd 2012 Sevana Oy Sevana OU Agricolankatu 11 Rohtlaane 12 00530 Helsinki 76911 Huuru kula Finland Estonia Harjumaa Phone 358 9 2316 4165 Phone 372 53485178 SEVANA IT solutions amp services Unknown parameter in codec performance measurement option power Parameter is missing in energy normalization management option enorm Unknown parameter in in energy normalization management option enorm File name to store reasons for audio quality loss is not specified Parameter is missing in delta correction management option decor Unknown parameter in delta correction management option decor Parameter is missing in integration mode option emode Unknown parameter in integration mode option emode Parameter is missing in signal type selection option mprio Unknown argument in signal type selection option mprio Value of initial delay is missing tdel Value
5. exe tst lic mode files src file Or272 wav tstf Dg001 wav acr auto npnt auto miter 1 ratem m Result will be Sevana Audio Quality Analyzer AQuA Wideband v 6 12 3 28 Copyright c 2012 by Sevana Oy Finland All rights reserved File Quality is Percent value 92 08 MOS value 4 89 or invoking it for the other degraded file aqua wb exe tst lic mode files src file Or272 wav tstf Dg002 wav acr auto npnt auto miter 1 ratem m Sevana Audio Quality Analyzer AQuA Wideband v 6 12 3 28 Copyright c 2012 by Sevana Oy Finland All rights reserved File Quality is Percent value 39 31 MOS value 2 23 Copyright Sevana Ltd 2012 Sevana Oy Sevana OU Agricolankatu 11 Rohtlaane 12 00530 Helsinki 76911 Huuru kula Finland Estonia Harjumaa Phone 358 9 2316 4165 Phone 372 53485178 SEVANA IT solutions amp services Adapting AQuA to actual environment AQUA parameters have pre set values by default however in some cases it is required to adapt the algorithm to actual environment which is network device or specific codec Majority of our customers don t require adjusting AQUA parameters but in some cases software tuning makes test results more consistent There is no common case when it s 100 required but some of our customers mentioned that when doing tests in mobile networks or VolP mobile this tuning gives better scores In case your tests show unexpected results means that AQUA engine or VAD may need
6. gt sets spectral analysis precision num 8 16 auto enables automated analysis precision detection according to sampling frequency Set delta correction mode decor lt on off gt enable disable delta correction Set spectrums integrating mode emode lt normal log 10log gt Sets one of the integration modes normal linear 10 log logarithmic Set signs type mprio lt on off gt sets signal type on music off voice Set initial delay tdel lt num gt sets delay in samples lt num gt from the beginning of test file In order to obtain correct number of samples for certain period in milliseconds please use this formula lt num gt delay ms sampling frequency Hz 1000 and vice versa delay ms lt num gt 1000 Sampling frequency ms Enable perception correction spfrcor lt on off gt turns on off perception correction This option introduces additional coefficients to specific frequencies is preferred for VoIP or G 729 signal only 8kHz only Copyright Sevana Ltd 2012 Sevana Oy Sevana OU Agricolankatu 11 Rohtlaane 12 00530 Helsinki 76911 Huuru kula Finland Estonia Harjumaa Phone 358 9 2316 4165 Phone 372 53485178 SEVANA IT solutions amp services Enable processing speech related frequency bands only voip lt on off gt turns on off processing of only speech related and specific frequency bands In particular this parameter forces AQUA to consider signals only
7. in the range between 300Hz and 3 4kHz telephone frequency band When the option is turned on differences in signals spectrum outside of the range above is not considered This option is recommended for VoIP mobile PSTN and converged networks transmitting telephone like speech signals Set psychoacoustics psyf lt on off gt sets psycho acoustic filter on off Set psychoacoustics psyn lt on off gt sets psycho acoustic normalyzer on off Set level gradation grad lt on off gt allows forbids amplitude gradation AQUA performance calculation tmc lt on off gt allows forbids quality score calculation time measurement Set average levels correction avlp lt on off gt enables disables average levels correction Smart energy normalization smtnrm lt on off gt enables disables smart energy normalization Performs energy normalization according to energy levels in integral spectrums of the most significant frequency band Export spectral pairs into CSV file specp lt num gt lt fname gt exports specified amount lt num gt of spectral pairs into the file specified lt fname gt lt num gt parameter may be equal to 8 16 or 32 This is important for visualizing differences in original and degraded signals spectrums Set program performance speed fst lt num gt sets program performance speed Increasing the speed decreases score accuracy lt num gt should be in the range between 0 0 slow and up t
8. of initial delay is negative or integer value set is incorrect tdel Parameter is missing in option spfrcor Unknown parameter in option spfrcor Parameter is missing in psycho acoustic model option psyf Unknown parameter in option setting psycho acoustic filter on psyf Parameter in time measurement option is missing tmc Unknown parameter in time measurement option tmc Parameter in smart energy normalization option is missing smtnrm Unknown parameter in smart energy normalization option smtnrm Parameter is missing in option avlp Unknown parameter in option avlp Parameter in psy normalizer management option is missing psyn Unknown parameter in psy normalizer management option psyn Incomplete parameters in spectrum pairs output option specp Copyright Sevana Ltd 2012 Sevana Oy Sevana OU Agricolankatu 11 Rohtlaane 12 00530 Helsinki 76911 Huuru kula Finland Estonia Harjumaa Phone 358 9 2316 4165 Phone 372 53485178 SEVANA IT solutions amp services Incorrect amount of spectrum pairs specp Parameter is missing in filter management option voip Unknown parameter in filter management option voip Incompatible set of parameters of psy normalization and amplitude ranges Parameter is missing in amplitude ranges management option grad Unknown parameter in amplitude ranges management option grad Parameter is missing in program performance speed option fs
9. on customer feedback and research made during the past years and we believe that AQuA 6 x can better objectively predict the subjective mean opinion scores as in a P 800 listening setup AQuA Benefits Among AQUA benefits one will definitely appreciate that e AQuA is available for Windows Linux and MAC OS operating systems e AQUA is availbale for both for 32 and 64 bit systems e AQuA is easy to deploy and use for software products development e AQUA provides perceptual estimation of audio quality and can be utilized in VoIP PSTN ISDN GSM CDMA LTE 4G sattelite and radio networks and combinations of those Copyright Sevana Ltd 2012 Sevana Oy Sevana OU Agricolankatu 11 Rohtlaane 12 00530 Helsinki 76911 Huuru kula Finland Estonia Harjumaa Phone 358 9 2316 4165 Phone 372 53485178 SEVANA IT solutions amp services AQuA Error Messages The following error messages may appear during AQUA run time When writing spectrum pairs into a file Please note if error occurs when writing file with spectrum pairs then error message can be found in the output file Wrong number of spectrum pairs Source file is too short Test file is too short Wrong numbers of spectrum pairs Please check AQUA Manual An error occurred while calculating spectrum pairs When reading command line parameters the following errors may occur Parameters listing error Mode error mode Data source error src Sound data generator
10. only 39 31 of similarity what corresponds to 2 23 MOS By the way this is an example of when AQUA does detect voice quality loss and PESQ does not please read more details about this test case on Microtronix page After test was executed log txt file contains quantitative reasons for voice quality loss Source SNR 63 160200 Degradated SNR 71 187480 Duration distortion Audio stretching corresponds to 1 41 percent Delay of audio signal activity Signal delayed by 100 000000 ms Audio signal activity mistiming unsynchronization is 1 25 percent Corrupted signal spectrum Overall spectral energy distortion approaches 62 18 Vibration along the whole spectrum 19 73 42 45 Significant distortion in low frequencies band Energy distortion approaches 32 27 Spectrum vibration in low frequency band 16 91 15 36 Significant distortion in medium frequencies band Energy distortion approaches 27 10 Amplification approaches 24 29 Copyright Sevana Ltd 2012 Sevana Oy Sevana OU Agricolankatu 11 Rohtlaane 12 00530 Helsinki 76911 Huuru kula Finland Estonia Harjumaa Phone 358 9 2316 4165 Phone 372 53485178 SEVANA IT solutions amp services Test two audio files and receive audio quality score In case we like to simply compare two audio files and get feedback on how similar the quality of the one under test is towards the reference audio we suggest invoking AQUA in the following manner aqua wb
11. result of the research of the harmonic signal masking by narrow band noise Zwiker has determined that the entire spectrum of audible frequencies could be divided into frequency groups or bands recognizable by the human ear Before Zwiker Fletcher who had named the selected frequency groups as critical bands of hearing had drawn a similar conclusion Critical bands determined by Fletcher and Zwiker differ since the former has defined bands by means of masking with noise and the latter from the relations of perceived loudness Sapozhkov has determined a critical band as a band of frequency speech range perceptible as a single whole In his earlier researches he even suggested that sound signals in a band could be substituted by an equivalent tone signal but experiments did not confirm this assumption Critical bands determined by Sapozhkov differ from those determined by Fletcher and Zwiker since Sapozhkov proceeded from the properties of speech signal Pokrovskij has also determined critical bands on the basis of speech signal properties According to his definition the bands provide equal probability of finding formants in them The value of spectrum energy in bands can be used for different purposes one of which is the sound signal quality estimation However using only one author s critical bands for example Zwiker s critical bands are used in prototype does not allow getting an estimation objective enough since they show onl
12. s wmsssnmmmmanamemannamimananzmannammananimaananama nana anammananima 23 AQUA ONNE AAA AA aaa aa RA aa AA aa AA 24 Sevana Audio Quality Analyzer AQuA Wideband vV 6 12 3 28 eeeecessccccceceeeseeeseneeeeeeeeesseeennaeeeeeeees 25 Sevana Audio Quality Analyzer AQuA Wideband v 6 12 3 28 eeceeesssecccceeeeseeeennneeeeeeeeeseeensnaeeeeeeees 25 PROVE NB Si ahaa E E AA ama ha Wa E aa aha aha kha waa hah hahaa aah ha kan 26 AQUA Error Mia Waza 27 When writing spectrum pairs into a file wwmwsnnmmannawmnnanimananzamannamiananimnanzam wane wana 27 When reading command line parameters the following errors May OCCUF s ssemmmenamemannnmamananza 27 When calculating quality score the following errors MAY OCCUL s ssssmmmenanamenananamannazamannnzemanaza 29 Introduction AQUA is a simple but powerful tool to provide perceptual voice quality testing and audio file comparison in terms of audio quality This is the easiest way to compare two audio files and test voice quality loss between original and Copyright Sevana Ltd 2012 Sevana Oy Sevana OU Agricolankatu 11 Rohtlaane 12 00530 Helsinki 76911 Huuru kula Finland Estonia Harjumaa Phone 358 9 2316 4165 Phone 372 53485178 SEVANA IT solutions amp services degraded files Besides this a most demanded functionality of the software can also test audio codecs and generate audio signals for voice quality testing
13. wami disisi tesina sersa ni nasining neriasi sinang siaren ni nasining nenna 14 Spectrum vibration in low frequency band 16 91 15 36 seesesesssssseesssersssssssesererrsssssseesreesssssssee 14 Significant distortion in medium frequencies band sc sicasssaiasuantacasasadesnsvanecadeasansaaasadaadeasadcavesneesinanandcavasie 14 Energy distortion approaches 27 10 Jo sssosissesiessesisiosissnsiiiosisr nsis osios i 14 Amplification approaches 24 29 Do 14 Compare two audio files and receive audio quality score ssssssessseesssssseeertetssssssserereeesssssserrreeeesssseet 15 Adapting AQUA to actual environment ssesssessssssssesssssseseseessseseserssresestscesssesesesserresesssesesasetessesesssssesese 16 Synchronizing reference and test files using AQUA 6 X cceeeesscceeesssneeeeeessneeeeessaeeeeeesaaeeesessnaeeseeesaaes 17 Analysis of possible reasons for voice and audio quality loss sswmmwnnemmmannmamananzamnanimanamima 20 Signal Noise Ratio SNR iii 21 D ration IO 114 sssrin Mere tee temp ee Mery tite E E E for cen ener err rent meres 21 Delay Advancing of audio signal activity wwwmevenannamemumenanawanenimim anuwani nawanezim waana 21 Audio signal activity mistiming s vs swwmsenammmananzamannamumananimannzimnnamamananemmaanania namimi nanea manani nanina 22 Corrupted sienal spea AA aa 22 Visualizing signals spectrum for analySIS
14. AQUA gives a unique opportunity to design your own voice quality testing solution not being dependent on particular hardware and software It is available as a library for Windows and Linux portable to Java and mobile devices Functionality Requirements AQUA is capable to work with audio files represented in wav or pcm formats Audio files should have the following parameters depending on the version one uses AQUA Voice 8kHz 16 bit Mono AQuA WB 8kHz and up to 192kHz 32 bit Mono Stereo Generate test signals Aqua allows generating test signals with the following parameters e Choosing voice type for synthesized sound male or female e Allows to define name of the synthesized sound or to run generation of full speech sounds distribution e Allows choosing duration for synthesized sound equal in amount of samples e Signals are built according to internal speech model e Allows test sound signals generated as short normal and long Test voice codecs e Allows output of codec speed performance indicator e Allows testing any codec library Windows only Compare wav files e Allows intrusive testing of original wav file against degraded wav file e Allows testing using internally generated audio test files e Allows direct wav files comparison quality wise e Allows measuring voice quality for any language Testing parameters AQUA supports the following parameters for voice quality testing e Choosing type of quality measuremen
15. SEVANA IT solutions amp services Sevana AQuA Audio Quality Analyzer 6 x Copyright Sevana Ltd 2012 Sevana Oy Agricolankatu 11 00530 Helsinki Finland Phone 358 9 2316 4165 User Manual T SEvANA AQUA AUDIO QUALITY ANALYZER the MARI MOBILE YANI AA ee mo AUDIO Q UALITY ANALYZER Sevana OU Rohtlaane 12 76911 Huuru kula Estonia Harjumaa Phone 372 53485178 SEVANA IT solutions amp services Contents CE AA WE KW EESE INESSE IS E EA OESE ECARE 2 MEDEA UC UAE spies AE acd peepee sides ea eis tid stanp cc dean SOs ti NAA oan Nadine EA 3 Functionality tere sta area innr a MBA UA WAFA encase WAHI KAABA Aaaa 4 Re eguirementS tees ct iiiaae a ae a a a aa ea aaaea a aada aa e eaa aE Aa 4 Genda test SIG NA 4 Test voice CODGOS Ha 4 Compare WA SA E E a E 4 Testne parameters a fact ect ar hardier aaa aaa 4 Scientific Back sround 2 istic ion tiaimieaieritinicnetientiebaieniinite EAEE EEEE EEEE Ei 5 AQuA Command Line parameters esessssssessseesesssserssssessssssesrsssressssseessssseersssresessssesessererssseeesssssesrsssressssse 7 Prot sounds names SA IA E re ner ety aren reer estrone 7 Print samples of program usage h exam seeeeeseseresssrersssrrrerssrrersssrertssrtetsssttentseterssstteetsserenesereeerssreeesee 8 Define program mode mode lt mod gt s ssssssssssssssessrettssssseterrtttssssssetrtttrtsstssttttttssssssttetttetesessseteeereesesstet 9
16. atu 11 Rohtlaane 12 00530 Helsinki 76911 Huuru kula Finland Estonia Harjumaa Phone 358 9 2316 4165 Phone 372 53485178 SEVANA IT solutions amp services Define program mode mode lt mod gt Defines AQuA mode of operation The following modes are available lt moa gt codec codec testing mode files audio file comparison mode folder folder comparison mode generate test signals generation mode For example mode codec aqua v exe tst lic mode files src file ORIGINAL_FILE tstf REFERENCE_FILE aqua v exe tst lic mode codec clibf lt DLL LIBRARY NAME src file lt TEST AUDIO FILE gt aqua v exe tst lic mode codec clibf GSM610 dll src file short pcm Command line argument clibf lt file gt codec library file name Use initial sound file as source or internal signal generator src file lt fname gt gen lt mode gt folder lt fname gt gt Determines source of initial sound lt file gt external sound file lt gen gt internal signal generator or lt folder gt external sound files from a folder In lt file gt mode one should specify name of audio file The signal generator mode may have one of the following option short normal or long In folder mode user specifies a path to audio files and file extensions wav or pcm Set type of weight coefficients ct lt ctype gt uniform linear logarithmic or htrsdelta Set name of the file under test tstf lt fname gt lt fold
17. e than 100 this means that data was inserted and analysis result will be Audio stretching corresponds to XX XX percent where XX XX corresponds to deviation from 100 Tolerance range for this value is set to 100 1 Delay Advancing of audio signal activity This metric represents signal shift in test file compared to the original and determines how much active level of the test signal delays advances active level of the reference original signal When it is delayed analysis returns the following Signal delayed by XX XX ms where KK KK is delay time in milliseconds Correspondently when the signal advances the original the return string is Signal advances the original by XX XX ms where XX XX is advancing time Copyright Sevana Ltd 2012 Sevana Oy Sevana OU Agricolankatu 11 Rohtlaane 12 00530 Helsinki 76911 Huuru kula Finland Estonia Harjumaa Phone 358 9 2316 4165 Phone 372 53485178 SEVANA IT solutions amp services Tolerance range for this value is interval of 50 ms Audio signal activity mistiming This metric represents unsynchronization of active levels in reference and test signals Original reference audio signal and test signal are merged to determine characteristics of audio activity and when the characteristics of audio activity do not match system increases unsynchronization counter After processing the final unsynchronization value is presented as percentage of cases when unsynchronization was de
18. ent algorithms development In all cases AQUA is the means end to end intrusive active testing which involves a reference audio file compared to the one passed through a network device or any other environment that may introduce degradation f e a voice codec In order to show how AQUA performs perceptual voice quality assessment we are going to use WAV files one can download from Microtronix web site http www microtronix ca pesq html However one can use any audio files within AQuA Wideband or those that are recorded at 8Khz sampling and are 16 bit mono in case of AQUA Voice Compare two audio files and learn about reasons for voice quality loss To compare two audio files in AQUA Command Line version when one is interested to get extensive feedback from the software we suggest to invoke AQUA in the following manner aqua wb exe tst lic mode files src file Or272 wav tstf Dg002 wav acr auto npnt auto miter 1 ratem m fau log txt As result you will received the following output Sevana Audio Quality Analyzer AQuA Wideband v 6 12 3 28 Copyright c 2012 by Sevana Oy Finland All rights reserved Copyright Sevana Ltd 2012 Sevana Oy Sevana OU Agricolankatu 11 Rohtlaane 12 00530 Helsinki 76911 Huuru kula Finland Estonia Harjumaa Phone 358 9 2316 4165 Phone 372 53485178 SEVANA IT solutions amp services File Quality is Percent value 39 31 MOS value 2 23 Thus one can see that file comparison gives
19. er 1 trim a 45 ratem m fau log txt Sevana Audio Quality Analyzer AQuA Wideband v 6 12 3 28 Copyright c 2012 by Sevana Oy Finland All rights reserved Evaluation Copyright Sevana Ltd 2012 Sevana Oy Sevana OU Agricolankatu 11 Rohtlaane 12 00530 Helsinki 76911 Huuru kula Finland Estonia Harjumaa Phone 358 9 2316 4165 Phone 372 53485178 SEVANA IT solutions amp services File Quality is Percent value 100 00 MOS value 5 00 and another file with silence in the beginning and the end of the file aqua wb exe tst lic mode files src file male wav tstf male_5s_delay_5s_end wav acr auto npnt auto miter 1 trim a 45 ratem m fau log txt Sevana Audio Quality Analyzer AQuA Wideband v 6 12 3 28 Copyright c 2012 by Sevana Oy Finland All rights reserved File Quality is Percent value 100 00 MOS value 5 00 Analysis of possible reasons for voice and audio quality loss Besides audio quality score AQUA gives a possibility to determine and analyze possible reasons that caused audio signal degradation Software automatically prepares analysis results that are stored in a log file Additional audio quality metrics returned by the system may not look trivial to understand and this chapter is devoted to the main principles of how these metrics are built and how one can interpret them AQUA returns additional metrics only in the case when they are out of range for their typical values exception Sig
20. er gt mode sets name of folder with the files to test Copyright Sevana Ltd 2012 Sevana Oy Sevana OU Agricolankatu 11 Rohtlaane 12 00530 Helsinki 76911 Huuru kula Finland Estonia Harjumaa Phone 358 9 2316 4165 Phone 372 53485178 SEVANA IT solutions amp services Set name of report file for folder processing mode frep lt fname gt Set name of the file generated by the speech model dst lt fname gt Generate full speech sounds distribution or synthesized sound sn lt all lt sname gt gt runs generation of full speech sounds distribution or defines name of the synthesized sound Examples aqua v exe tst lic mode generate sn all dst SPEECH_MODEL_FILE Here are options for generating speech model audio signal aqua v exe tst lic mode generate sn all dst generated_01 pcm instead of all parameter one can specify separate sounds from the table of sounds you can see in the manual aqua v exe tst lic mode generate sn a0 voit female slen 8000 dst generated_02 pcm aqua v exe tst lic mode generate sn i0 voit male slen 8000 dst generated_03 pcm For separate sounds one can also set type of voice voit male female and duration of the sound to be generated slen 8000 Set voice type voit lt female male gt sets voice type for synthesized sound Set duration slen lt num gt sets duration for synthesized sound equal to lt num gt samples Set quality loss or naturallness qt lt quali
21. es 30 Multidirectional spectrum changes vibration is considered when greater than 2 5 in low frequencies 7 in medium frequencies and 15 in high frequencies Unidirectional distortions no matter positive or negative are considered when greater than 5 in low frequencies 10 in medium frequencies and 25 in high frequencies And now let s analyze Or272 wav against Dg002 wav which according to the information from Microtronix web site was equalized such that there is far less low frequency and high frequency energy when compared to the original file Our online service gives the following Sevana Audio Quality Analyzer AQuA Wideband v 6 12 3 28 AE Percent value 28 77 KEK MOS value 1639 Source SNR 63 160200 Degradated SNR 69 740421 Duration distortion Analysis shows that during audio processing or transfer over communication channels audio fragments might have been lost from the original signal Tolerance range for this value is set to 1 Audio shrinking corresponds to 1 05 percent Characteristics of audio activity between the origianl and degraded file don t match We recommend Copyright Sevana Ltd 2012 Sevana Oy Sevana OU Agricolankatu 11 Rohtlaane 12 00530 Helsinki 76911 Huuru kula Finland Estonia Harjumaa Phone 358 9 2316 4165 Phone 372 53485178 SEVANA IT solutions amp services unsynchrnization value below 2 Audio signal activity mistiming unsynchronization is 5 18 percent
22. gt lt mwsnmmmmanamimananemmannnimnnanim wanawa aanmm manane 10 Set number of link points npnt lt num auto gt wwwwwememenannaanemimimananwwnwemi mwanana anawaza 10 Set precision of spectral analysis acr lt NUM AULOD ceceeecccceeeeeeeennneeeeeeeeeeseeesaaeeeeeceeeseeetnnaaeeeeeeers 11 Set envelope smoothing level miter lt M owes carssvnscanasabadnteicossacduq dunddupenayadlbtw cap sadennnbslduusvadnudtionbiargarnntes 11 Turn on waiting for key press after showing voice quality output gCN wwmmwwmmwwmmwwmmww 11 Print reason of quality loss fau EMAINIO Hess a cnasasarceciaaatenedsesnadednsenmsabeadanadsenadhe id sadsnsddenndeads oacecaddaeideeddoaned 11 Set voice quality output type ratem lt m P gt wwwwwwmmmananananewimimananawanemim Meee Hae een ee 11 Set spectral analysis precision acr lt MUM auto gt eee cece eeeeeeeeeceeeeeeeennneeeeeeeeeeeseeennaaeeeeeeeeseeeeenaeeeeeeers 11 Set delta correction mode decor lt on Off gt sswmwmmannaamnnnmmmananmmmanamim nanma manani laye ines 11 Set spectrums integrating mode emode lt normal log 1010g gt wwwwwemwanmememmmananawawema 11 Set signsl type mprio lt on OT si557 cctscquaeadangsidoanengss eardeg saessecsaseananasansgacgaseatanicasateasagonansteiesesseeatanecneases 11 Set mita de
23. lay AS AA aaa 11 Enable perception correction spfrcor lt on Off gt wwwwwwwwmawememeanwnawwwimim anwani mwm 11 Enable processing speech related frequency bands only voip lt on Off gt w wemwwmemememammmmwwa 12 Set psychoacousties psyf lt 0n aaa 12 Set psychoacoustics psyn lt on off gt sivccsicesasssnnatecesdvnsgeassvasneetdecsdueseeasnnabivie soeesaoatuessavetdsetiuedonssbuadivetmeniens 12 Set level gradation grad lt on WDE sap ssngcasaa e saa catunacdeaiaaesiqsatuncdeeate sasq teteasaneaiwtaseavhecaadnatanens eadaassaesiunceeaee 12 AQuA performance calculation tmc lt on Off gt wwwwwmmmananaanawwwmimwananawemim anwani tees 12 Copyright Sevana Ltd 2012 Sevana Oy Sevana OU Agricolankatu 11 Rohtlaane 12 00530 Helsinki 76911 Huuru kula Finland Estonia Harjumaa Phone 358 9 2316 4165 Phone 372 53485178 SEVANA IT solutions amp services Set average levels correction avlp lt on Off gt wwwmmwwwwwawwmemimanwwnwanwmi ma sand suaansdenndeaddaans 12 Smart energy normalization smtnrm lt on Off gt sswmmmsnamemannammanannimaanamimananzi manani naamin 12 Export spectral pairs into CSV file specp lt num gt lt fname gt sssmmmmnnaamenanamamannnzamannnzmanamaa 12 Set program performance speed fst lt NUM gt
24. na OU Agricolankatu 11 Rohtlaane 12 00530 Helsinki 76911 Huuru kula Finland Estonia Harjumaa Phone 358 9 2316 4165 Phone 372 53485178 SEVANA IT solutions amp services High frequencies are those that are greater than 3000 Hz When analyzing frequency bands we use different tolerance range for different bands Distortion in low frequencies is considered when they are greater than 5 in medium frequencies 10 and in high frequencies 30 Multidirectional spectrum changes vibration are considered when they are greater than 2 5 in low frequencies 7 in medium frequencies and 15 in high frequencies Unidirectional distortions no matter positive or negative are considered when they are greater than 5 in low frequencies 10 in medium frequencies and 25 in high frequencies Visualizing signals spectrum for analysis AQUA 5 x has a special parameter to store pairs of spectrum energy in critical bands of original and degraded audio to a csv file aqua wb tst lic mode files src file male wav tstf male_5s_delay_5s_end wav npnt auto miter 1 ratem p fau report txt tmc on gch psyn off psyf off smtnrm on enorm on grad on specp 32 spect csv This command produces the following output Sevana Audio Quality Analyzer AQuA Wideband v 6 12 3 28 Copyright c 2012 by Sevana Oy Finland All rights reserved File Quality is Percent value 91 37 PESQvalue 3 30 Calculating time 1 424000 sec Press any key to co
25. nal Noise Ratio SNR that is always present in the report In case the metrics are within the range the system returns Cannot determine the major reason for audio quality loss Copyright Sevana Ltd 2012 Sevana Oy Sevana OU Agricolankatu 11 Rohtlaane 12 00530 Helsinki 76911 Huuru kula Finland Estonia Harjumaa Phone 358 9 2316 4165 Phone 372 53485178 SEVANA IT solutions amp services Signal Noise Ratio SNR These metrics represent SNR both in the original and degraded files Source SNR XX XX Degradated SNR XX XX These metrics show the signal noise ratio of the original and degraded signals Typically signal quality gets lower when SNR value decreases or significantly increases in the test audio Duration distortion This metric represents continuity of compared audio files Ideally amount of audio data in the original signal and file under test should be the same During audio processing or transfer over communication channels audio fragments may be lost as well as inserted into the audio If such audio degradation took place then value of this metric is lower than 100 The bigger the difference the stronger the degradation however this metric does not consider possible starting pauses When the value is less than 100 this means that audio data was lost and analysis result will be Audio shrinking corresponds to XX XX percent where XX XX corresponds to deviation from 100 When the actual value is mor
26. nor 024 v lt lt Noised 025 vi lt lt Noised 026 zh lt lt Noised 027 z lt lt Noised 028 z lt lt Noised 029 r lt lt Noised 030 r lt lt Noised 031 b lt lt Voiced Explosiv 032 b lt lt Voiced Explosiv 033 g lt lt Voiced Explosiv 034 g lt lt Voiced Explosiv 035 d lt lt Voiced Explosiv 036 d lt lt Voiced Explosiv 037 f lt lt UnVoiced 038 f lt lt UnVoiced 039 h lt lt UnVoiced 040 h lt lt UnVoiced 041 s lt lt UnVoiced 042 s lt lt UnVoiced 043 sh lt lt UnVoiced 044 sch lt lt UnVoiced 045 k lt lt Occlusive 046 k lt lt Occlusive 047 p lt lt Occlusive 048 p lt lt Occlusive 049 t lt lt Occlusive 050 t lt lt Occlusive 051 c lt lt Occlusive 052 ch lt lt Occlusive 053 lt lt Silencer Print samples of program usage h exam exam prints samples of program usage In order to test voice quality between original and reference files use the following set of parameters aqua v exe tst lic mode files src file ORIGINAL_FILE tstf REFERENCE_FILE To test voice codec provided as a DLL library use the following set of parameters aqua v exe tst lic mode codec clibf lt DLL_LIBRARY_NAME gt src file lt TEST AUDIO FILE gt e g aqua v exe tst lic mode codec clibf GSM610 dll src file short wav Copyright Sevana Ltd 2012 Sevana Oy Sevana OU Agricolank
27. ntinue File spect csv contains 32 pairs related to spectrum energies of both files so after importing the file into electronic spreadsheet we can plot a diagram visualizing differences in signals spectrum 120 00 100 00 80 00 Copy 60 00 Seva Agric 40 00 0053 Finla 20 00 Phor 0 00 mm ee mai a ia am m SEVANA IT solutions amp services As one can see the difference is not big and the reasons for received MOS score are stored in report txt Source SNR 73 214584 Degradated SNR 73 277180 Duration distortion Audio stretching corresponds to 9 81 percent Delay of audio signal activity Signal delayed by 4990 000000 ms Audio signal activity mistiming unsynchronization is 1 14 percent As one can see the main reasons are mistiming and delay which we have not removed and if we remove it as described in previous chapter aqua wb tst lic mode files src file male wav tstf male_5s_delay_5s_end wav npnt auto miter 1 ratem p fau report txt tmc on gch psyn off psyf off smtnrm on enorm on grad on trim r 5 specp 32 spect csv we receive result showing that the files are of identical quality Sevana Audio Quality Analyzer AQuA Wideband v 6 12 3 28 Copyright c 2012 by Sevana Oy Finland All rights reserved File Quality is Percent value 99 94 PESQvalue 4 49 Calculating time 1 386000 sec Press any key to continue AQuA Online AQUA Online is an olnine service
28. o 1 0 fast Set silence trimming trim src tst lt a r gt lt level gt sets silence trimming type absolute a should be below average signal level or relative r threshold should be below SNR level the lt level gt parameter is set in dB and varies from 0 0 up to 120 0 e trim src run trimming for source file only e trim tst run trimming for depredated file only e trim run trimming for both files synchronizes both audio files in time domain Copyright Sevana Ltd 2012 Sevana Oy Sevana OU Agricolankatu 11 Rohtlaane 12 00530 Helsinki 76911 Huuru kula Finland Estonia Harjumaa Phone 358 9 2316 4165 Phone 372 53485178 SEVANA IT solutions amp services AQuA Command Line usage Most of our customers represent the following business segments e VolP service providers e Mobile service providers e PSTN service providers e Sattelite service providers e Audio and web conferencing providers e Radio communications e Unified communications e Solution providers for telecom AQUA helps telecom business to solve a wide range of tasks e test conference bridges quality when dialing from different locations e monitor quality on a conference bridge e monitor quality to certain destinations e monitor quality at different terminations by end to end testing with termination s echo server e test quality in converged networks f e Mobile VoIP e device testing in noisy environment e audio improvem
29. or speed for example it is possible to receive rough estimation quickly o by signal type using different bands for speech signals and sound signals in general e resulting estimations correlate well with that of MOS e quality estimations received for speech signals can be translated in values of various scores of intelligibility AQuA Command Line parameters AQUA Usage AquA XX lt license file gt options Print sounds names h sndn sndn prints list of sounds names There are 54 sounds in the database Num Name Type Num Name Type 000 a0 lt lt Vocal 001 al lt lt Vocal 002 a2 lt lt Vocal 003 a4 lt lt Vocal 004 e0 lt lt Vocal 005 el lt lt Vocal 006 10 lt lt Vocal 007 il lt lt Vocal 008 i4 lt lt Vocal 009 00 lt lt Vocal 010 ol lt lt Vocal O11 o4 lt lt Vocal 012 u0 lt lt Vocal 013 ul lt lt Vocal 014 u4 lt lt Vocal 015 y0 lt lt Vocal 016 yl lt lt Vocal 017 1 lt lt Sonor 018 LI lt lt Sonor 019 m lt lt Sonor 020 m lt lt Sonor 021 n lt lt Sonor Copyright Sevana Ltd 2012 Sevana Oy Sevana OU Agricolankatu 11 Rohtlaane 12 00530 Helsinki 76911 Huuru kula Finland Estonia Harjumaa Phone 358 9 2316 4165 Phone 372 53485178 SEVANA IT solutions amp services 022 nt lt lt Sonor 023 je lt lt So
30. quence of actions hearing threshold processing fluid level masking spectrum separation into tones and noises creating masks from tone components creating masks from noise components joining tone and noise mask components joining current mask with post mask preparing post mask for the next frame wo aon oanPpwNn bP creating mask for the previous frame Hearing threshold corresponds to ear sensitivity towards intensity of sound energy and minimal sound pressure that produces feeling of hearing is called hearing threshold Threshold level depends on type of sound fluctuations and measuring conditions One of possible options to detect hearing threshold implemented in AQuA 5 x is standardized in ISU R 226 Copyright Sevana Ltd 2012 Sevana Oy Sevana OU Agricolankatu 11 Rohtlaane 12 00530 Helsinki 76911 Huuru kula Finland Estonia Harjumaa Phone 358 9 2316 4165 Phone 372 53485178 SEVANA IT solutions amp services Psycho acoustic model implemented in AQuA 5 3 introduces the so called range of detectable loudness which is minimal change of signal amplitude detectable by a human ear It s a well known fact that depending on signal loudness level and frequency human perception varies from 2 up to 40 AQUA algorithms have certain advantages e itis universal since it allows measuring signals quality from various sources and processed in different ways e one can optimize quality estimation depending on the purpose o f
31. t Program performance parameter is out of range fst Parameter s is missing in silence trimming option trim Unknown type of silence level detection trim Incorrect silence level trim Source audio files folder or extension are not defined src Data source type is not defined tstf Test files folder is not defined tstf Report file name is missing frep When calculating quality score the following errors may occur Error opening source file Error opening file under test degraded Error files have different sampling frequencies Error sampling frequency is not supported Error files have different channels Error sampling frequency in source file is not supported Error sampling frequency in degralated file is not supported Copyright Sevana Ltd 2012 Sevana Oy Sevana OU Agricolankatu 11 Rohtlaane 12 00530 Helsinki 76911 Huuru kula Finland Estonia Harjumaa Phone 358 9 2316 4165 Phone 372 53485178
32. t overall quality loss or voice naturalness e Choosing filenames for original test and generated audio files e Define type of weight coefficients uniform linear or logarithmic e Allows energy normalization e Allows setting envelope smoothing level from 1 to 10 Copyright Sevana Ltd 2012 Sevana Oy Sevana OU Agricolankatu 11 Rohtlaane 12 00530 Helsinki 76911 Huuru kula Finland Estonia Harjumaa Phone 358 9 2316 4165 Phone 372 53485178 SEVANA IT solutions amp services e Allows choosing source for original sound external file or generated internally e Contains audio synchronization and voice activity detection e Provides reasons for voice quality loss quite unique feature on the market o Duration distortion o Changes in signal spectrum o Distortion detection in low medium and high frequency bands e Provides voice quality feedback in o Percentage of similarity o MOS like value o PESQ like value e Enabling advanced psycho acoustic model o Psycho acoustic filter o Normalization to loudness level at 1kHz o Spectrums transform into detectable range of loudness e Audio synchronization trimming silence in the beginning and end of the test file e Adjusting ratio between calculation performance and quality score forecast accuracy Scientific Background The human ear is a non linear system which produces an effect named masking Masking occurs on hearing a message against a noisy background or masking sounds As
33. tected If the metric value is not zero analysis result represents it as Audio signal activity mistiming unsynchronization is XX XX percent where XX XX is percentage of unsynchronization The value is not considered if it is less than 1 Corrupted signal spectrum This represents a set of metrics reflecting differences in integral energy spectrums of the original signal and audio under test If overall spectrums difference is more than 15 than analysis returns the following string Corrupted signal spectrum If difference in spectrums is multidirectional goes both into positive and negative zones analysis returns the following string Vibration along the whole spectrum XX XX YY YY where XX XX and YY YY are deviations to negative and positive zones correspondently Tolerance range of the deviation is 5 If spectrum distortions are unidirectional only negative or only positive analysis returns this string Amplification approaches YY YY When distortions are positive or Attenuation approaches XX XX Yo when distortions are negative Other metrics returned by analysis correspond to distortions occurred in different frequency groups Analysis of different frequency bands performs in a similar manner to spectrum analysis When talking about frequency bands in question we consider Low frequencies below 1000 Hz Medium frequencies from 1000 Hz to 3000 Hz Copyright Sevana Ltd 2012 Sevana Oy Seva
34. that we implemented to show our customers and partners how simply one can create an advanced audio quality analysis service The online script uses the same information presented in this Copyright Sevana Ltd 2012 Sevana Oy Sevana OU Agricolankatu 11 Rohtlaane 12 00530 Helsinki 76911 Huuru kula Finland Estonia Harjumaa Phone 358 9 2316 4165 Phone 372 53485178 SEVANA IT solutions amp services manual to provide end users with full analysis of audio quality and recommendations on what we consider important to improve in order to achieve higher perceptual quality Access to online demo or service is available on demand Let s use the same voice files and test Or272 wav against Dg001 wav here is output of our online service based on the latest AQUA version Sevana Audio Quality Analyzer AQuA Wideband v 6 12 3 28 kkk Percent value 93 590 kkk MOS value 4 93 R Source SNR 63 160200 Degradated SNR 60 457320 Duration distortion Analysis shows that during audio processing or transfer over communication channels audio fragments might have been lost from the original signal Tolerance range for this value is set to 1 Audio shrinking corresponds to 1 33 percent Low frequencies below 1000 Hz Medium frequencies from 1000 Hz to 3000 Hz High frequencies are those that are greater than 3000 Hz Distortions in low frequencies are considered when greater than 5 in medium frequencies 10 and in high frequenci
35. tly decrease the final quality score In order to trim irrelevant parts of the test signal in the beginning and end of the degraded file one just needs to invoke AQUA with a trim parameter aqua wb exe tst lic mode files src file male wav tstf male_5s_delay_5s_end_ 36db_whitenoise wav acr auto npnt auto miter 1 trim r 5 ratem m fau log txt AQUA output will be Sevana Audio Quality Analyzer AQuA Wideband v 6 12 3 28 Copyright c 2012 by Sevana Oy Finland All rights reserved File Quality is Copyright Sevana Ltd 2012 Sevana Oy Sevana O Agricolankatu 11 Rohtlaane 12 00530 Helsinki 76911 Huuru kula Finland Estonia Harjumaa Phone 358 9 2316 4165 Phone 372 53485178 SEVANA IT solutions amp services Percent value 74 59 MOS value 3 98 or one can use another option as described above aqua wb exe tst lic mode files src file male wav tstf male_5s_delay_5s_end_ 36db_whitenoise wav acr auto npnt auto miter 1 trim a 45 ratem m fau log txt AQUA output will be Sevana Audio Quality Analyzer AQuA Wideband v 6 12 3 28 Copyright c 2012 by Sevana Oy Finland All rights reserved File Quality is Percent value 75 28 MOS value 4 02 However in order to be absolutely sure that the trimming works properly let s test it with an artificially created file containing silence aqua wb exe tst lic mode files src file male wav tstf male_5s_delay_5s_beginning wav acr auto npnt auto mit
36. tuning We suggest to start with these parameters first e npnt o This parameter sets the amount of linking points required to catch different holes inside the signal By default the value is 5 e miter o Sets amount of voice activity detector frames that are used during smoothing By default it s 5 This is required to smooth the detector s vibration For example aqua wb exe tst lic mode files src file Or272 wav tstf Dg002 wav acr auto npnt 1 miter 5 ratem m Result is Sevana Audio Quality Analyzer AQuA Wideband v 6 12 3 28 Copyright c 2012 by Sevana Oy Finland All rights reserved File Quality is Percent value 39 73 MOS value 2 25 or invoking it for the other degraded file Copyright Sevana Ltd 2012 Sevana Oy Sevana OU Agricolankatu 11 Rohtlaane 12 00530 Helsinki 76911 Huuru kula Finland Estonia Harjumaa Phone 358 9 2316 4165 Phone 372 53485178 SEVANA IT solutions amp services aqua wb exe tst lic mode files src file Or272 wav tstf Dg001 wav acr auto npnt 1 miter 5 ratem m fau log txt Sevana Audio Quality Analyzer AQuA Wideband v 6 12 3 28 Copyright c 2012 by Sevana Oy Finland All rights reserved File Quality is Percent value 90 22 MOS value 4 82 In fact this result is much closer to what one would hear however the file was degraded One can find the reasons for voice quality loss in the log txt file e g Source SNR 63 160200 Degraded SNR 60
37. ty naturalness gt sets type of quality measurement overall quality loss or voice naturalness Enable indication of codec speed performance power lt on off gt enables output of codec speed performance indicator Enable energy normalization enorm lt on off gt enables energy normalization Set number of link points npnt lt num auto gt sets number of link points num 1 10 auto enables detection of optimal amount of linking points recommended Copyright Sevana Ltd 2012 Sevana Oy Sevana OU Agricolankatu 11 Rohtlaane 12 00530 Helsinki 76911 Huuru kula Finland Estonia Harjumaa Phone 358 9 2316 4165 Phone 372 53485178 SEVANA IT solutions amp services Set precision of spectral analysis acr lt num auto gt sets spectral analysis precision num 8 16 auto enables automated analysis precision detection according to sampling frequency Set envelope smoothing level miter lt num gt smoothing level is in the range of 1 10 Turn on waiting for key press after showing voice quality output gch turns on waiting for a key press after output of voice quality Print reason of quality loss fau lt fname gt prints reasons for quality loss to the file specified Set voice quality output type ratem lt m p gt voice audio quality in percentage m MOS score prediction objective score of P 800 MOS prediction Set spectral analysis precision acr lt num auto
38. vvsenanawemumenanaanwnmemiminunanawewimim ananena manane 12 Set silence trimming trim srcl tst lt a r gt le Ve gt z 5 5 dessvasananinssavesavanananesaravesayegavansinraneeivansenananareciseganes 12 AQUA Command Line Usage ii www 13 Compare two audio files and learn about reasons for voice quality IOSS sssmmmmananmemannmmaa 13 Source SNR 63160200 sienen iana 14 Deoradated SNR AISHA SO ivoire e rE E rene a ee EN 14 Duration distorto wA EIERE A ia rrai EEO EE SiS Ee ASEE EAS nEri EE AIEE A FES RS SI EESE ES aaRS 14 Audio stretching corresponds to 1 41 DELCONTisisisiscscisairnairmaimnandanen NOOR 14 Delay of audio signal activity ss AKIWA irii AAA nedd sued psd subanedd ated ee dd seaaaeadatadubeasede 14 Signal delayed by 100 000000 MS csciciciniccsstemacensinteasoeslonssaceletessenslnieemnbtenkeanitasteciniasdesnedaaceieudaateancastenness 14 Audio signal activity mistiming unsynchronization is 1 25 percent cccccccccccccccccccceecceeeeeeeeeeeeeeeeeeseeeseeenees 14 Corr pted sional SHEM 14 Overall spectral energy distortion approaches 62 18 QW siscssnissssasnsnascsansnasensnsaascassvasseasscanssaapeaaneasaeasacsensas 14 Vibration along the whole spectrum 19 73 42 45 P ossooooososossesssssssssssssssessssssssseseseeesessreseeeeeeeseseeeeeeene 14 Significant distortion in low frequencies band cesesaaiocsascexcguadeatnesacnedeanvsnsansticandenaelae esntcastoasasaninanoasdcsaidad 14 Energy distortion approaches 32 27 Jo
39. y one of the aspects of perception or speech production AQuA can determine energy in various critical bands as well as in logarithmic and resonator bands that allows taking into consideration more properties of hearing and speech processing Taking into account that the bands determined by Pokrovskij and Sapozhkov are better for speech signal and not for sound signal in general allows increasing the accuracy of estimation depending on its purpose Copyright Sevana Ltd 2012 Sevana Oy Sevana OU Agricolankatu 11 Rohtlaane 12 00530 Helsinki 76911 Huuru kula Finland Estonia Harjumaa Phone 358 9 2316 4165 Phone 372 53485178 SEVANA IT solutions amp services AQUA utilized research results of the above mentioned scientists implementing different algorithms in one software solution AQuA also has several advantages compared to other existing voice quality measurement software Besides critical bands new AquA implements a more advanced psycho acoustic model which consists of three layers e psy filtering e level normalization e transform into detectable range Psycho acoustic model is based on dependencies obtained during experiments The most complex phase is psy filtering represented at Fig 1 Previous Current frame frame gly ola SE U Pre G mask Psy masker A Final frame v Fig 1 General scheme of psy filtering Masking procedure includes the following se
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