Exfo EXpert IPTV Test Tools (FTB-200v2) Uživatelský manuál stáhnout pdf (Strana 60)

60



VQmon/HDcalculatesqualitymetricsintheseburstandgapstates,andthencombinesthem

togeneratetheoverallqualityscoreonuserexperi ence.Thesecalculationsarebasedonthe

resultsofnumerouss ubjectivevoice/videoqualityanalysisteststhatindicatethereisnotan

instantaneouschangeinperceivedqualitywhenatransitionbetw

eenthegapandburststates

occurs,butratherthattheperceivedqualityexponentially“decays”fromonelevelto

another.Forexample,a100‐millisecondburstof“noise”ismuchlessannoyingthana10

secondburstof“noise”.

Figure2‐8illustratestheVQmon4‐stateMarkovmodel.TheVQmon4‐stateMarkovmodelis

define

dashavingthefollowingstatesandassociatedtransitions:

Table2‐1.VQmon4‐stateMarkovmodelstatetransitiondescriptions



1 2 ... 55 56 57 58 59 60 61 62 63 64 65 ... 81 82

Žádné komentáře

Exfo EXpert IPTV Test Tools (FTB-200v2) Uživatelský manuál Strana 60