SIST EN 301 712 V7.3.1:2003
(Main)Digital cellular telecommunications system (Phase 2+) (GSM); Adaptive Multi Rate (AMR) speech; ANSI-C code for the AMR speech codec (GSM 06.73 version 7.3.1 Release 1998)
General Information
- Abstract
CR @ SA#6
- Status
- Published
- Publication Date
- 30-Nov-2003
- Current Stage
- 6060 - National Implementation/Publication (Adopted Project)
- Start Date
- 01-Dec-2003
- Due Date
- 01-Dec-2003
- Completion Date
- 01-Dec-2003
- Mandate
- T-172
Overview
SIST EN 301 712 V7.3.1:2003 defines the reference ANSI-C source code for the Adaptive Multi-Rate (AMR) speech codec used in the digital cellular telecommunications system (GSM Phase 2+). Developed by the Slovenski inštitut za standardizacijo (SIST) and harmonized with EN 301 712, this standard ensures a bit-exact implementation of the AMR speech transcoder, integral for GSM networks. The AMR codec is fundamental for high-quality voice compression in mobile communication, supporting multiple bit rates and robust voice transmission in various network conditions.
Key Topics
- Adaptive Multi-Rate (AMR) Speech Codec: The AMR codec is a widely adopted speech coding standard in GSM, allowing efficient voice transmission at several bit rates.
- Reference ANSI-C Source Code: The provided C code ensures interoperability by offering a standard, bit-exact implementation for GSM AMR speech encoding and decoding.
- Testing and Verification: The standard includes procedures for installation and verification of the codec using official GSM test sequences.
- Portability and Platform Support: ANSI-C is used to ensure code portability across different hardware and operating systems, facilitating ease of integration and testing.
- Codec Features:
- Voice Activity Detection (VAD)
- Comfort Noise Generation (CNG)
- Discontinuous Transmission (DTX)
- Lost frame substitution and muting
- Coding Structure: The code structure is designed for modularity, maintainability, and instantiability, supporting multiple independent codec instances as required in complex telecommunications equipment.
Applications
- Mobile Communications (GSM Networks): The AMR codec source code standardizes voice quality and transmission reliability in GSM cellular systems, facilitating interoperability amongst equipment from different manufacturers.
- Embedded Systems and Mobile Devices: Device manufacturers use the reference C code to implement speech codecs in mobile phones, base stations, and network infrastructure.
- Telecommunications Equipment Certification: The bit-exact reference implementation is critical during the development and certification process, ensuring all equipment meets GSM performance and conformance requirements.
- Software Development and Integration: Developers use the code as a baseline for proprietary enhancements or for integration in larger cellular communication stacks.
- Testing and Quality Assurance: The reference code and associated test sequences make it possible to verify codec behavior under various network and channel conditions, supporting product validation and ongoing quality assurance.
Related Standards
The effectiveness and interoperability of the AMR codec depend on its alignment with other GSM and telecommunications standards, such as:
- GSM 06.74: Test sequences for the GSM Adaptive Multi-Rate speech codec.
- GSM 06.90: Details on AMR speech transcoding processes.
- GSM 06.91: Substitution and muting for lost frames in AMR channels.
- GSM 06.92: Comfort noise generation techniques for AMR.
- GSM 06.93: Discontinuous transmission (DTX) for AMR.
- GSM 06.94: Voice activity detection for AMR channels.
Practical Value
Implementing SIST EN 301 712 V7.3.1:2003 delivers:
- Interoperability in GSM networks by standardizing AMR codec functionality.
- Reliable voice quality, even under varying mobile network conditions.
- Efficient voice compression, reducing bandwidth requirements without sacrificing user experience.
- Consistent certification and testing for equipment manufacturers and carriers.
By standardizing on this reference, mobile communication products can meet international GSM requirements, assure global compatibility, and deliver the expected quality of service to end users.
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Frequently Asked Questions
SIST EN 301 712 V7.3.1:2003 is a standard published by the Slovenian Institute for Standardization (SIST). Its full title is "Digital cellular telecommunications system (Phase 2+) (GSM); Adaptive Multi Rate (AMR) speech; ANSI-C code for the AMR speech codec (GSM 06.73 version 7.3.1 Release 1998)". This standard covers: CR @ SA#6
CR @ SA#6
SIST EN 301 712 V7.3.1:2003 is classified under the following ICS (International Classification for Standards) categories: 33.070.50 - Global System for Mobile Communication (GSM). The ICS classification helps identify the subject area and facilitates finding related standards.
SIST EN 301 712 V7.3.1:2003 is associated with the following European legislation: Standardization Mandates: T-172. When a standard is cited in the Official Journal of the European Union, products manufactured in conformity with it benefit from a presumption of conformity with the essential requirements of the corresponding EU directive or regulation.
SIST EN 301 712 V7.3.1:2003 is available in PDF format for immediate download after purchase. The document can be added to your cart and obtained through the secure checkout process. Digital delivery ensures instant access to the complete standard document.
Standards Content (Sample)
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.Digital cellular telecommunications system (Phase 2+) (GSM); Adaptive Multi Rate (AMR) speech; ANSI-C code for the AMR speech codec (GSM 06.73 version 7.3.1 Release 1998)33.070.50Globalni sistem za mobilno telekomunikacijo (GSM)Global System for Mobile Communication (GSM)ICS:Ta slovenski standard je istoveten z:EN 301 712 Version 7.3.1SIST EN 301 712 V7.3.1:2003en01-december-2003SIST EN 301 712 V7.3.1:2003SLOVENSKI
STANDARD
ETSIEN301712V7.3.1(2000-06)EuropeanStandard(Telecommunicationsseries)Digitalcellulartelecommunicationssystem(Phase2+);AdaptiveMultiRate(AMR)speech;ANSI-CcodefortheAMRspeechcodec(GSM06.73version7.3.1Release1998)GLOBALSYSTEMFORMOBILECOMMUNICATIONSRSIST EN 301 712 V7.3.1:2003
ETSIETSIEN301712V7.3.1(2000-06)2(GSM06.73version7.3.1Release1998)ReferenceREN/SMG-110673Q7R2KeywordsDigitalcellulartelecommunicationssystem,GlobalSystemforMobilecommunications(GSM)AMR,ANSICCodeETSI650RoutedesLuciolesF-06921SophiaAntipolisCedex-FRANCETel.:+33492944200Fax:+33493654716SiretN°34862356200017-NAF742CAssociationàbutnonlucratifenregistréeàlaSous-PréfecturedeGrasse(06)N°7803/88ImportantnoticeIndividualcopiesofthepresentdocumentcanbedownloadedfrom:http://www.etsi.orgThepresentdocumentmaybemadeavailableinmorethanoneelectronicversionorinprint.Inanycaseofexistingorperceiveddifferenceincontentsbetweensuchversions,thereferenceversionisthePortableDocumentFormat(PDF).Incaseofdispute,thereferenceshallbetheprintingonETSIprintersofthePDFversionkeptonaspecificnetworkdrivewithinETSISecretariat.Usersofthepresentdocumentshouldbeawarethatthedocumentmaybesubjecttorevisionorchangeofstatus.InformationonthecurrentstatusofthisandotherETSIdocumentsisavailableathttp://www.etsi.org/tb/status/Ifyoufinderrorsinthepresentdocument,sendyourcommentto:editor@etsi.frCopyrightNotificationNopartmaybereproducedexceptasauthorizedbywrittenpermission.Thecopyrightandtheforegoingrestrictionextendtoreproductioninallmedia.©EuropeanTelecommunicationsStandardsInstitute2000.Allrightsreserved.SIST EN 301 712 V7.3.1:2003
ETSIETSIEN301712V7.3.1(2000-06)3(GSM06.73version7.3.1Release1998)ContentsIntellectualPropertyRights.4Foreword.41Scope.52References.53Definitionsandabbreviations.63.1Definitions.63.2Abbreviations.64Ccodestructure.64.1ContentsoftheCsourcecode.64.2Programexecution.74.3Codingstyle.74.4Codehierarchy.74.5Variables,constantsandtables.114.5.1DescriptionofconstantsusedintheC-code.114.5.2DescriptionoffixedtablesusedintheC-code.114.5.3StaticvariablesusedintheC-code.135Homingprocedure.176Fileformats.236.1Speechfile(encoderinput/decoderoutput).236.2Modecontrolfile(encoderinput).236.3Parameterbitstreamfile(encoderoutput/decoderinput).23AnnexA(informative):ChangeRequestHistory.24History.25SIST EN 301 712 V7.3.1:2003
ETSIETSIEN301712V7.3.1(2000-06)4(GSM06.73version7.3.1Release1998)IntellectualPropertyRightsIPRsessentialorpotentiallyessentialtothepresentdocumentmayhavebeendeclaredtoETSI.TheinformationpertainingtotheseessentialIPRs,ifany,ispubliclyavailableforETSImembersandnon-members,andcanbefoundinETSISR000314:"IntellectualPropertyRights(IPRs);Essential,orpotentiallyEssential,IPRsnotifiedtoETSIinrespectofETSIstandards",whichisavailablefromtheETSISecretariat.LatestupdatesareavailableontheETSIWebserver(http://www.etsi.org/ipr).PursuanttotheETSIIPRPolicy,noinvestigation,includingIPRsearches,hasbeencarriedoutbyETSI.NoguaranteecanbegivenastotheexistenceofotherIPRsnotreferencedinETSISR000314(ortheupdatesontheETSIWebserver)whichare,ormaybe,ormaybecome,essentialtothepresentdocument.ForewordThisEuropeanStandard(Telecommunicationsseries)hasbeenproducedbytheSpecialMobileGroup(SMG).ThepresentdocumentprovidesthebitexactdefinitionoftheAdaptiveMultiRate(AMR)speechtrafficcodecforthedigitalcellulartelecommunicationssystem.ThepresentdocumentcontainsanelectroniccopyoftheANSI-CcodefortheGSMAdaptiveMulti-Ratecodec,givenintheassociatedfile"en_301712v070301p0.zip".TheANSI-CcodeisnecessaryforabitexactimplementationoftheAdaptiveMultiRatespeechtranscoder(GSM06.90[3]),VoiceActivityDetection(GSM06.94[7]),comfortnoise(GSM06.92[5]),DiscontinuousTransmission(GSM06.93[6])andexamplesolutionsforsubstitutingandmutingoflostframes(GSM06.91[4]).Theassociatedfile"en_301712v070301p0.zip"containsa"readme.txt"file,whichexplainstheprocedureforinstallationandusageoftheANSI-Ccodefiles.ThecontentsofthepresentdocumentissubjecttocontinuingworkwithinSMGandmaychangefollowingformalSMGapproval.ShouldSMGmodifythecontentsofthepresentdocumentitwillbere-releasedwithanidentifyingchangeofreleasedateandanincreaseinversionnumberasfollows:Version7.x.ywhere:7indicatesRelease1998ofGSMPhase2+.xtheseconddigitisincrementedforallchangesofsubstance,i.e.technicalenhancements,corrections,updates,etc.ythethirddigitisincrementedwheneditorialonlychangeshavebeenincorporatedinthespecification.NationaltranspositiondatesDateofadoptionofthisEN:19May2000DateoflatestannouncementofthisEN(doa):31August2000DateoflatestpublicationofnewNationalStandardorendorsementofthisEN(dop/e):28February2001DateofwithdrawalofanyconflictingNationalStandard(dow):28February2001SIST EN 301 712 V7.3.1:2003
ETSIETSIEN301712V7.3.1(2000-06)5(GSM06.73version7.3.1Release1998)1ScopeThepresentdocumentcontainsanelectroniccopyoftheANSI-CcodefortheGSMAdaptiveMulti-Ratecodec.TheANSI-CcodeisnecessaryforabitexactimplementationoftheAdaptiveMultiRatespeechtranscoder(GSM06.90[3]),VoiceActivityDetection(GSM06.94[7]),comfortnoise(GSM06.92[5]),DiscontinuousTransmission(GSM06.93[6])andexamplesolutionsforsubstitutingandmutingoflostframes(GSM06.91[4]).2ReferencesThefollowingdocumentscontainprovisionswhich,throughreferenceinthistext,constituteprovisionsofthepresentdocument.• Referencesareeitherspecific(identifiedbydateofpublication,editionnumber,versionnumber,etc.)ornon-specific.• Foraspecificreference,subsequentrevisionsdonotapply.• Foranon-specificreference,thelatestversionapplies.• Anon-specificreferencetoanETSshallalsobetakentorefertolaterversionspublishedasanENwiththesamenumber.• ForthisRelease1998document,referencestoGSMdocumentsareforRelease1998versions(version7.x.y).[1]GSM01.04:"Digitalcellulartelecommunicationssystem(Phase2+);Abbreviationsandacronyms".[2]GSM06.74:"Digitalcellulartelecommunicationssystem(Phase2+);TestsequencesfortheGSMAdaptiveMulti-Rate(AMR)speechcodec".[3]GSM06.90:"Digitalcellulartelecommunicationssystem(Phase2+);AdaptiveMulti-Rate(AMR)speechtranscoding".[4]GSM06.91:"Digitalcellulartelecommunicationssystem(Phase2+);SubstitutionandmutingoflostframeforAdaptiveMulti-Rate(AMR)speechtrafficchannels".[5]GSM06.92:"Digitalcellulartelecommunicationssystem(Phase2+);ComfortnoiseaspectsforAdaptiveMulti-Rate(AMR)speechtrafficchannels".[6]GSM06.93:"Digitalcellulartelecommunicationssystem(Phase2+);Discontinuoustransmission(DTX)forAdaptiveMulti-Rate(AMR)speechtrafficchannels".[7]GSM06.94:"Digitalcellulartelecommunicationssystem(Phase2+);VoiceActivityDetector(VAD)forAdaptiveMulti-Rate(AMR)speechtrafficchannels".SIST EN 301 712 V7.3.1:2003
ETSIETSIEN301712V7.3.1(2000-06)6(GSM06.73version7.3.1Release1998)3Definitionsandabbreviations3.1DefinitionsDefinitionoftermsusedinthepresentdocument,canbefoundinGSM06.90[3],GSM06.91[4],GSM06.92[5],GSM06.93[6]andGSM06.94[7].3.2AbbreviationsForthepurposesofthepresentdocument,thefollowingabbreviationsapply:ANSIAmericanNationalStandardsInstituteETSEuropeanTelecommunicationStandardGSMGlobalSystemforMobilecommunicationsI/OInput/OutputRAMRandomAccessMemoryROMReadOnlyMemoryForabbreviationsnotgiveninthissubclauseseeGSM01.04[1].4CcodestructureThisclausegivesanoverviewofthestructureofthebit-exactCcodeandprovidesanoverviewofthecontentsandorganizationoftheCcodeattachedtothepresentdocument.TheCcodehasbeenverifiedonthefollowingsystems:-SunMicrosystemsworkstationsandGNUgcccompiler;-DECAlphaworkstationsandGNUgcccompiler;-IBMPC/ATcompatiblecomputerswithLinuxoperatingsystemandGNUgcccompiler;ANSI-C9899wasselectedastheprogramminglanguagebecauseportabilitywasdesirable.4.1ContentsoftheCsourcecodeTheCcodedistributionhasallfilesintherootlevel.Thedistributedfileswithsuffix"c"containthesourcecodeandthefileswithsuffix"h"aretheheaderfiles.TheROMdataiscontainedmostlyinfileswithsuffix"tab".TheCcodedistributionalsocontainsonespeechcoderinstallationverificationdatafile,"spch_dos.inp".Thereferenceencoderoutputfileisnamed"spch_dos.cod",thereferencedecoderinputfileisnamed"spch_dos.dec"andthereferencedecoderoutputfileisnamed"spch_dos.out".ThesefourfilesareformattedsuchthattheyarecorrectforanIBMPC/ATcompatiblecomputer.Thesamefileswithreversedbyteorderofthe16bitwordsarenamed"spch_unx.inp","spch_unx.cod","spch_unx."dec"and"spch_unx.out",respectively.FinalverificationistobeperformedusingtheGSMAdaptiveMulti-RatetestsequencesdescribedinGSM06.74[2].MakefilesareprovidedfortheplatformsinwhichtheCcodehasbeenverified(listedabove).Oncethesoftwareisinstalled,thisdirectorywillhaveacompiledversionofencoderanddecoder(thebit-exactCexecutablesofthespeechcodec)andalltheobjectfiles.SIST EN 301 712 V7.3.1:2003
ETSIETSIEN301712V7.3.1(2000-06)7(GSM06.73version7.3.1Release1998)4.2ProgramexecutionTheGSMAdaptiveMulti-Ratecodecisimplementedintwoprograms:-(encoder)speechencoder;-(decoder)speechdecoder.Theprogramsshouldbecalledlike:-encoder[encoderoptions];-decoder[decoderoptions].Thespeechfilescontain16-bitlinearencodedPCMspeechsamplesandtheparameterfilescontainencodedspeechdataandsomeadditionalflags.Theencoderanddecoderoptionswillbeexplainedbyrunningtheapplicationswithoption–h.Seethefilereadme.txtformoreinformationonhowtoruntheencoderanddecoderprograms.4.3CodingstyleTheCcodeiswrittenaccordingtothefollowingstructuringconventions.Eachfunctionfunc()thatneedsstaticvariablesisconsideredamodule.Amoduleconsistsof:-a'statestructure'(struct)combiningthestaticvariablesofthemodule-threeauxiliaryfunctionsfunc_init(),func_reset(),andfunc_exit().-theprocessingfunctionfunc()itselfTheinitializationfunctionfunc_init()allocates(fromtheheap)anewstatestructure,callsthefunc_reset()function,storesthepointertothenewlyallocatedstructureinitsfirstfunctionparameter,andreturnswithavalueof0ifcompletedsuccessfuloravalueof1otherwise.Theresetfunctionfunc_reset()takesapointertothestatestructureandresetsallmembersofthestructuretoapredefinedvalue('homing').Theexitfunctionfunc_exit()performsanynecessarycleanupandfreesthestatestructurememory.Theprocessingfunctionfunc()alsotakesapointertothestatestructureaswellasallothernecessaryparametersandperformsitstaskusing(andpossiblymodifying)thevaluesinthestatestructure.Ifamodulecallsothermodules,thehigherlevelstatestructurecontainsapointertothelowerlevelstatestructures,andtheinit,reset,andexitfunctionsrecursivelycallthecorrespondinglowerlevelfunctions.Bythisconvention,thecodebecomes"instantiable"(morethanonecopyofamodulecanbeusedinthesameprogram)andthestaticdatahierarchyisclearlyvisibleinthecode.4.4CodehierarchyFigures1to4arecallgraphsthatshowthefunctionsusedinthespeechcodec,includingthefunctionsofVAD,DTX,andcomfortnoisegeneration.Eachcolumnrepresentsacalllevelandeachcellafunction.Thefunctionscontaincallstothefunctionsinrightwardsneighbouringcells.Thetimeorderinthecallgraphsisfromthetopdownwardsastheprocessingofaframeadvances.AllstandardCfunctions:printf(),fwrite(),etc.havebeenomitted.Also,nobasicoperations(add(),L_add(),mac(),etc.)ordoubleprecisionextendedoperations(e.g.L_Extract())appearinthegraphs.TheinitialisationofthestaticRAM(i.e.callingthe_initfunctions)isalsoomitted.Thebasicoperationsarenotcountedasextendingthedepth,thereforethedeepestlevelinthissoftwareislevel7.Theencodercallgraphisbrokendownintothreeseparatecallgraphs,Table1to3.SIST EN 301 712 V7.3.1:2003
ETSIETSIEN301712V7.3.1(2000-06)8(GSM06.73version7.3.1Release1998)Table1:SpeechencodercallstructureSpeech_Encode_FramePre_Processcod_amrCopyVad11filter_bankfirst_filter_stagefilter5filter3level_calculationvad_decisioncomplex_estimate_adaptcomplex_vadnoise_estimate_updateupdate_cntrlhangover_additionVad21block_normr_fftc_fftfn10Log10Log2Log2_normPow2tx_dtx_handlerlpcAutocorrLag_windowLevinsonlspAz_lspChebpsQ_plsf_5Lsp_lsfLsf_wtVq_subvecVq_subvec_sReorder_lsfLsf_lspInt_lpc_1and3_2Lsp_azGet_lsp_polInt_lpc_1and3Lsp_azGet_lsp_polQ_plsf_3Lsp_lsfLsf_wtCopyVq_subvec3Vq_subvec4Reorder_lsfLsf_lspInt_lpc_1to3_2Lsp_azGet_lsp_polInt_lpc_1to3Lsp_azGet_lsp_polCopydtx_bufferCopyLog2Log2_normdtx_encLsp_lsfReorder_lsfLsf_lspSet_zerolsp_resetCopyQ_plsf_resetcl_ltp_resetPitch_fr_resetcheck_lsppre_bigWeight_AiResiduSyn_filtol_ltpPitch_olvad_tone_detection_update2Lag_maxvad_tone_detection2Inv_sqrtcomp_corr2hp_max2vad_complex_detection_update2Pitch_ol_wghcomp_corr2Lag_max2vad_tone_detection_update2vad_tone_detection2gmed_nhp_max2vad_complex_detection_update2vad_pitch_detectionLTP_flag_update3subframePreProcWeight_AiSyn_filtResiduCopycl_ltpPitch_frgetRangeNorm_CorrConvolveInv_sqrtsearchFracInterpol_3or6Enc_lag3Enc_lag6(continued)1OptiontocalloneortheotherVADoption2SpecifictoVADoption13SpecifictoVADoption2SIST EN 301 712 V7.3.1:2003
ETSIETSIEN301712V7.3.1(2000-06)9(GSM06.73version7.3.1Release1998)Table1(concluded):SpeechencodercallstructurePred_lt_3or6ConvolveG_pitchcheck_gp_clippingq_gain_pitchcbsearchseeTable2gainQuantseeTable3update_gp_clippingCopysubframePostProcSyn_filtPred_lt_3or6ConvolvePrm2bitsInt2binTable2:cbsearchcallstructurecbsearchcode_2i40_9bitscor_h_xset_signcor_hInv_sqrtsearch_2i40build_codecode_2i40_11bitscor_h_xset_signcor_hInv_sqrtsearch_2i40build_codecode_3i40_14bitscor_h_xset_signcor_hInv_sqrtsearch_3i40build_codecode_4i40_17bitscor_h_xset_signcor_hInv_sqrtsearch_4i40build_codecode_8i40_31bitscor_h_xset_sign12k2Inv_sqrtcor_hInv_sqrtsearch_10and8i40build_codecompress_codecompress10code_10i40_35bitscor_h_xset_sign12k2Inv_sqrtcor_hInv_sqrtsearch_10and8i40build_codeq_pTable3:gainQuantcallstructuregainQuantgc_pred_copyCopygc_predLog2Log2_normLog2_normcalc_filt_energiescalc_target_energyMR475_update_unq_predgc_pred_updateMR475_gain_quantMR475_quant_store_resultsLog2Log2_normgc_pred_updategc_predLog2Log2_normLog2_normG_codeq_gain_codePow2MR795_gain_quantq_gain_pitchMR795_gain_code_quant3calc_unfilt_energiesLog2Log2_normgain_adaptgmed_nMR795_gain_code_quant_modsqrt_l_expQua_gainPow2gc_pred_updateSIST EN 301 712 V7.3.1:2003
ETSIETSIEN301712V7.3.1(2000-06)10(GSM06.73version7.3.1Release1998)Table4:SpeechdecodercallstructureSpeech_Decode_FrameBits2prmBin2intDecoder_amrrx_dtx_handlerDecoder_amr_resetlsp_avg_resetD_plsf_resetec_gain_pitch_resetec_gain_code_resetgc_pred_resetBgn_scd_resetSet_zeroph_disp_resetdtx_dec_resetCopySet_zerodtx_decCopyLsf_lspInit_D_plsf_3CopyD_plsf_3Reorder_lsfCopyLsf_lsppseudonoiseLsp_lsfReorder_lsfLsp_AzGet_lsp_polA_ReflLog2Log2_normBuild_CN_codepseudonoiseSyn_filtLsf_lsplsp_avgCopyD_plsf_3Reorder_lsfCopyLsf_lspInt_lpc_1to3Lsp_AzGet_lsp_polD_plsf_5Reorder_lsfCopyLsf_lspInt_lpc_1and3Lsp_AzGet_lsp_polDec_lag3Pred_lt_3or6Dec_lag6decode_2i40_9bitsdecode_2i40_11bitsdecode_3i40_14bitsdecode_4i40_17bitsdecode_8i40_31bitsdecompress_codedecompress10ec_gain_pitchgmed_nd_gain_pitchec_gain_pitch_updatedecode_10i40_35bitsDec_gainLog2Log2_normgc_predLog2Log2_normLog2_normPow2gc_pred_updateec_gain_codegmed_ngc_pred_average_limetedgc_pred_updateec_gain_code_updated_gain_codegc_predLog2Log2_normLog2_normPow2gc_pred_updateInt_lsfCb_gain_averageph_disp_releaseph_disp_lockph_dispsqrt_l_expEx_ctrlgmed_nagc2Inv_sqrtSyn_filtBgn_scdgmed_ndtx_dec_activity_updateCopyLog2Log2_normlsp_avgPost_FilterCopyWeight_AiResiduSet_zeroSyn_filtPreemphasisagcenergy_oldenergy_newenergy_oldInv_sqrtPost_ProcessSIST EN 301 712 V7.3.1:2003
ETSIETSIEN301712V7.3.1(2000-06)11(GSM06.73version7.3.1Release1998)4.5Variables,constantsandtablesThedatatypesofvariablesandtablesusedinthefixedpointimplementationaresignedintegersin2'scomplementrepresentation,definedby:-Word1616bitvariable;-Word3232bitvariable.Furthermoresomeenumtypesareused,allpossibletorepresentwithonebyte,andabooleanFlag.4.5.1DescriptionofconstantsusedintheC-codeThissectioncontainsalistingofallglobalconstantsdefinedincnst.h.Table5:GlobalconstantsConstantValueDescriptionL_TOTAL320totalsizeofspeechbuffer.L_WINDOW240windowsizeinLPanalysisL_FRAME160framesizeL_FRAME_BY280framesizedividedby2L_SUBFR40subframesizeL_CODE40codevectorlengthNB_TRACK5numberoftracksSTEP5codebookstepsizeNB_TRACK_MR1024numberoftracksmodemr102STEP_MR1024codebookstepsizemodemr102M10orderofLPfilterMP1(M+1)orderofLPfilter+1LSF_GAP205minimumdistancebetweenLSFafterquantization;50Hz=205LSP_PRED_FAC_MR12221299MR122LSPpredictionfactor(0.65Q15)AZ_SIZE44sizeofarrayofLPfiltersin4subframes(4*M+4)PIT_MIN_MR12218minimumpitchlag(MR122mode)PIT_MIN20minimumpitchlag(allothermodes)PIT_MAX143maximumpitchlagL_INTERPOL(10+1)lengthoffilterforinterpolationL_INTER_SRCH4lengthoffilterforCLLTPsearchinterpolationMU26214factorfortiltcompensationfilter0.8AGC_FAC29491factorforautomaticgaincontrol0.9L_NEXT40overheadinLPanalysisSHARPMAX13017maximumvalueofpitchsharpeningSHARPMIN0minimumvalueofpitchsharpeningMAX_PRM_SIZE57max.num.ofparamsMAX_SERIAL_SIZE244max.num.ofserialbitsGP_CLIP15565pitchgainclipping=0.95N_FRAME7oldpitchgainsinaveragecalculationEHF_MASK816bitrepresentationofallsamplesintheencoderhomingframe(leftjustification)4.5.2DescriptionoffixedtablesusedintheC-codeThissectioncontainsalistingofallfixedtablessortedbysourcefilenameandtablename.AlltabledataisdeclaredasWord16.SIST EN 301 712 V7.3.1:2003
ETSIETSIEN301712V7.3.1(2000-06)12(GSM06.73version7.3.1Release1998)Table6:FixedtablesFileTablenameLengthDescriptionc2_9pf.ctrackTable4*5tracktableforalgebraiccodebooksearch(MR475,MR515)cod_amr.cgamma110spectralexpansionfactorscod_amr.cgamma1_12k210spectralexpansionfactorscod_amr.cgamma210spectralexpansionfactorsdtx_dec.clsf_hist_mean_scale10initializationvaluesforDTXlsfparametersdtx_dec.cdtx_log_en_adjust9leveladjustmentsforechmodeec_gains.ccdown7attenuationfactorsforcodebookgainec_gains.cpdown7attenuationfactorsforadaptivecodebookgaingc_pred.cpred4algebraiccodebookgainMApredictorcoefficientsgc_pred.cpred_MR1224algebraiccodebookgainMApredictorcoefficients(MR122)pitch_fr.cmode_dep_parm72parametersdefiningtheadaptivecodebooksearchpermodepost_pro.ca3HPfiltercoefficients(denominator)inPost_Processpost_pro.cb3HPfiltercoefficients(numerator)inPost_Processpre_proc.ca3HPfiltercoefficients(denominator)inPre_Processpre_proc.cb3HPfiltercoefficients(numerator)inPre_Processpred_lt.cinter_661interpolationfiltercoefficientspstfilt.cgamma3_MR12210spectralexpansionfactorspstfilt.cgamma310spectralexpansionfactorspstfilt.cgamma4_MR12210spectralexpansionfactorspstfilt.cgamma410spectralexpansionfactorsbitno.tabprmno9numberofbitsforeachmodebitno.tabprmnofsf8numberofparametersforLPCandfirstsubframeforeachmode(usedfordecoderhomingprocedure)bitno.tabbitno9pointerstothebitno_MR.tablesbitno.tabbitno_MR47517numberofbitsperparametertotransmit(MR475)bitno.tabbitno_MR51519numberofbitsperparametertotransmit(MR515)bitno.tabbitno_MR5919numberofbitsperparametertotransmit(MR59)bitno.tabbitno_MR6719numberofbitsperparametertotransmit(MR67)bitno.tabbitno_MR7419numberofbitsperparametertotransmit(MR74)bitno.tabbitno_MR79523numberofbitsperparametertotransmit(MR795)bitno.tabbitno_MR10239numberofbitsperparametertotransmit(MR102)bitno.tabbitno_MR12257numberofbitsperparametertotransmit(MR122)bitno.tabbitno_MRDTX5numberofbitsperparametertotransmit(MRDTX)c2_11pf.tabstartPos12trackstartsearchpositionforfirstpulsec2_11pf.tabstartPos24trackstartsearchpositionforsecondpulsec2_9pf.tabstartPos16trackstartsearchpositioncorrwght.tabcorrweight251weightingofthecorrelationfunctioninopenloopLTPsearch(MR102)d_homing.tabdhf8pointerstothedhf_MR…tablesd_homing.tabdhf_MR47517parametervaluesforthedecoderhomingframe(MR475)d_homing.tabdhf_MR51519parametervalu
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