ITU G.726:1990
ITU G.726:1990 40, 32, 24, 16 Kbit/s Adaptive Differential Pulse Code Modulation (adpcm)
Table of Contents
1General1.1ADPCMencoder
1.2ADPCMdecoder
2ADPCMencoderprinciples
2.1InputPCMformatconversion
2.2Differencesignalcomputation
2.3Adaptivequantizer
2.4Inverseadaptivequantizer
2.5Quantizerscalefactoradaptation
2.6Adaptationspeedcontrol
2.7Adaptivepredictorandreconstructedsignal
calculator
2.8Toneandtransitiondetector
3ADPCMdecoderprinciples
3.1Inverseadaptivequantizer
3.2Quantizerscalefactoradaptation
3.3Adaptationspeedcontrol
3.4Adaptivepredictorandreconstructedsignal
calculator
3.5Toneandtransitiondetector
3.6OutputPCMformatconversion
3.7Synchronouscodingadjustment
4Computationaldetails
4.1Inputandoutputsignals
4.2Descriptionofvariablesanddetailed
specificationofsub-blocks
APPENDIXINetworkaspects
I.1Generaltransmissionconsiderations
I.2Interactionwithotherprocesses
I.3InteractionwithcodinglawsotherthanPCM
I.4Encoder/decodersynchronization
I.5Synchronouscodingadjustment
I.6Speechperformance
I.7Voicefrequencytelegraphperformance
I.8Dataperformance
I.9Dualtonemulti-frequency(DTMF)signalling
I.10Facsimile
APPENDIXIIDigitaltestsequencesfortheverification
ofthealgorithmsinRecommendationG.726
II.1Purposeofdigitaltestsequences
II.2Disketteinterfaceandformat