Codificador Mp3 en Matlab

ESCUEL MILITAR DE INGENIERIA

CODIFICADOR WAV A MP3 EN MATLAB Nombre: Ariel Ortiz Cer! "3##"#$LP 6to Semestre Ingeniería Electronica

CODIFICACIÓN MP3 1. OB OBE! E!I" I"OS OS a. OBE!I"O OBE!I"O #ENE$A% #ENE$A% Pro%r!m!r &' (oi)(!or e' M!tL!b *&e tr!'+,orme

!r(-i.o+ e !&io /0!. ! MP3/ &. OBE!I"O OBE!I"OS S ESPECIFICOS ESPECIFICOS E+t!ble(er 1!r2metro+ e l! (oi)(!(i' MP3/ Ie'ti)(!r lo+ 1ro(e+o+ *&e 'o+ lle.e ! re!liz!r l! (oi)(!(i' MP3/ E+t!ble(er ,&'(io'e+ i'termei!+ el 1ro(e+o/ '. MA$CO MA$CO !EO$I !EO$ICO CO E% ENCABE(ADO DE %AS !$AMAS

No e4i+te e'(!bez!o 1ri'(i1!l e !r(-i.o e' el ,orm!to e !&io MPEG/ E' 5+te el e'(!bez!o e+ i'i.i&!l 1!r! (!! tr!m! 6,r!%me'to e !r(-i.o7/ C&!'o 'o +e *&iere ere leer eer i',orm!(i' e &' !r( !r(-i.o MP38 &+&!lme'te e+ +&)(ie'te e'(o'tr!r l! 1rimer! tr!m!8 leer +& e'(!bez!o 9 !+&mir *&e l!+ otr!+ tr!m!+ +o' i%&!le+/ Pero 5+te 'o e+ +iem1re el (!+o 1or e;em1lo8 e4i+te' !l%&'o+ !r(-i.o+ (o' t!+!+ e bit+ .!ri!ble+8 o'e (!! tr!m! 1o+ee +& 1ro1i! t!+! e bit+/ E+to +e -!(e (o' el )' e m!'te'er (o'+t!'te l! (!li! el +o'io &r!'te too el !r(-i.o/ Otro m5too &+!o 1!r! m!'te'er (o'+t!'te l! (!li! e +o'io e+ em1le!r m2+ bit+ 6(o' 6(o' !9& !9&! ! el el b$8 Coi)(!(i' A.!'z!! e A&io 6AAC8  Advanced Audio Coding78 ! l! *&e t!mbi5' +e re)ere' (omo MPEG>$ C!1!  o MPEG>$ NBC 6 Non-Backwards Compatible 7 9! *&e e+ i'(om1!tible (o' el MPEG># 9 (o' lo+ otro+ ,orm!to+ el MPEG>$/ L! 1!rte>3 e+t2 or%!'iz!! (omo +e m&e+tr! e' l! +i%&ie'te )%&r!/

E' l! t!bl! *&e +e m&e+tr! ! (o'ti'&!(i'8 +e re+&me' l!+ (!r!(ter@+ti(!+ e (!! 'i.el 1!r! el !&io MPEG>#/

El !&io e lo+ CD=+ 6,re(&e'(i! e /# z8 (oi)(!(i' ! #J bit+8 moo e+t5reo7 re*&iere &'! t!+! e tr!'+,ere'(i! 6!'(-o e b!'!7 m&9 (er(!'o ! #/ Mb1+ )

Slo o(-o +e%&'o+ e !&io (o'+&me' !1ro4im!!me'te #/ MB e e+1!(io e !lm!(e'!mie'to/ Em1le!'o el 1rimer e+*&em! e (oi)(!(i'8 C!1! I8 l! (!li! CD +e !l(!'z! (o' &'! t!+! e !1e'!+ 3" b1+ 5+te ,&e el e+*&em! &+!o e' el DCC 6Digital Compact Cassette8 C!+ete Com1!(to Di%it!l7 e l! )rm! P-ili1+/ El +i%&ie'te e+*&em!8 C!1! II8 lo%r!b! l! (!li! CD (o' !1e'!+ #$ b1+ +& &+o m2+ (om#8 +i' im1ort!r el e+*&em! 6(!1!7 e (oi)(!(i'/

CODIFICADO$

PSICOAC/S!ICO

U' (oi)(!or 1+i(o!(#8 +e m&e+tr! e' el +i%&ie'te i!%r!m! e blo*&e+/

MPE#01 Caa I. P!r! l! C!1! I8 el blo*&e MAPEO DEL TIEMPO

A LA FRECUENCIA e+ &' b!'(o e )ltro+ 1oli,2+i(o b!+!o e' l! DCT8 el (&!l i.ie el !&io e' 3$ +&bb!'!+ i%&!lme'te e+1!(i!!+ e' ,re(&e'(i! 6e+ e*&i.!le'te ! im1leme't!r )ltro+ 1!+!b!'!78 (!! &'! !1ort!'o #$ m&e+tr!+ 1!r! &' tot!l e 3" m&e+tr!+8 l!+ (&!le+ +e i'(l&9e' e' lo *&e -! re(ibio el 'ombre e TRAMA/ El MODELO PSICOACSTICO +lo &+! e'm!+(!r!mie'to e' ,re(&e'(i!8 1or meio e &'! FFT e #$ 1&'to+/ L! +!li! e l! FFT +e &+! 1!r! e'(o'tr!r t!'to el e'm!+(!r!mie'to to'!l 6+i'&+oi!l7 (omo el 'o>to'!l 6r&io7 e l! +e!l/ C!! (om1o'e'te e e'm!+(!r!mie'to 1ro&(e &' &mbr!l e e'm!+(!r!mie'to e1e'ie'te e +& ,re(&e'(i!8 i'te'+i! 9 to'!li!/ P!r! (!! +&bb!'!8 lo+ &mbr!le+ e e'm!+(!r!mie'to i'i.i&!le+ +e (ombi'!' 1!r! ,orm!r el &mbr!l

e

e'm!+(!r!mie'to

%lob!l/

El

&mbr!l

e

e'm!+(!r!mie'to +e (om1!r! (o' el m24imo 'i.el e +e!l 1!r! l! +&bb!'!8 1ro&(ie'o &'! rel!(i' +e!l ! m2+(!r! 6SMR8 Si%'!l>to>M!+ R!tio78 *&e e+ l! e'tr!! !l +i%&ie'te

blo*&e

6(&!'tiz!or7/

El CUANTIQADORCODIFICADOR 1rimero e4!mi'! l!+ m&e+tr!+ e (!! +&bb!'!8 e'(o'tr!'o el .!lor m24imo !b+ol&to e e+!+ m&e+tr!+8 9 re!liz!'o l! (&!'tiz!(i' (o' +ei+ bit+/ E+to+ +ei+ bit+ +e ll!m!' FACTOR DE ESCALA PARA LA SUBBANDA/ L&e%o +e etermi'! l! re1!rti(i' e bit+ 1!r! (!! +&bb!'! mi'imiz!'o l! SMR tot!l (o' re+1e(to ! lo+ bit+ re1!rtio+ 1!r! (!! +&bb!'!/ Por #/

Est4n5ar MPE#0'. N&mer!o e m!'er! ,orm!l (omo ISOIEC

MPEG #3"#" 6Coi)(!(i' %e'5ri(! 1!r! i',orm!(i' e im2%e'e+ e' mo.imie'to 9 el !&io !+o(i!o78 ,&e !o ! (o'o(er e' #8 t!' +lo &' !o e+1&5+ el 1rimer e+t2'!r8 9 +e e'(&e'tr! (o'+tit&io 1or m2+ 1!rte+ *&e el e+t2'!r !'terior/

El e+t2'!r e' +& 1rimer! ,!+e ,&e &'! +im1le e4te'+i' e' l!+ (!1!(i!e+ e (om1re+i' 9 (oi)(!(i' el 1rimer e+t2'!r8 mie'tr!+ *&e e' l! +e%&'! +e e+!rroll!ro' '&e.o+ !l%oritmo+ *&e im1li(!b!' i,ere'te+ m5too+ 1!r! re!liz!r l! (om1re+i' t!'to e .ieo (omo e !&io8 1ero e' e+te 1&'to +e +!(ri)( l! (om1!tibili! (o' el e+t2'!r !'terior e' !l%&'!+ 2re!+/ L! +i%&ie'te t!bl! ! &'! .i+i' %e'er!l e l!+ i,ere'te+ 1!rte+/

Parte 1 Sistema) e+ +imil!r !l 1rimer e+t2'!r8 re!liz! l!

mi+m! ,&'(i'8 1ero !*&@ l! re!liz! e o+ m!'er!+ i,ere'te+8 el &;o e 1ro%r!m! 9 el &;o e tr!'+1orte8 (!! &'o o1timiz!o 1!r! i,ere'te+ (o';&'to+ e !1li(!(io'e+/ El &;o e 1ro%r!m! +e 1e'+ 1!r! !mbie'te+ libre+ e errore+ 9 e+ !1ro1i!o 1!r! !1li(!(io'e+ *&e i'.ol&(re' 1ro(e+!mie'to 1or +o,t0!re8 mie'tr!+ *&e el &;o e tr!'+1orte +e &+! 1!r! !lm!(e'!mie'to o tr!'+mi+i' e' meio+ *&e 1re+e'te' r&io 9 15ri!+/

Parte ' "i5eo) me;or! l!+ (!1!(i!e+ 1!r! (om1re+i' e

.ieo

el

e+t2'!r

!'terior/

Parte 3 A75io) !em2+ e !%re%!r (!1!(i! m<i(!'!l8

t!mbi5' 1ro1or(io'! (!1!(i! 1!r! m# 9 MPEG>$/ Parte CC8 Meio+ e Alm!(e'!mie'to Di%it!l> Com!'o 9 Co'trol7/

CODIFICACIÓN MP3 %A CAPA III

El i'+tit&to Fr!&'-o,er IIS 6 !nstitut "r !ntegrierte Schaltungen8 I'+tit&to 1!r! el Cir(&ito I'te%r!o78 e Alem!'i!8 e' &'o e +&+ %r&1o+ e tr!b!;o +e (o'(e'tr! e' l! tr!'+mi+i' i'!l2mbri(! e !to+ 9 e' l! (oi)(!(i' e l!+ +e!le+ e !&io 9 .ieo/ E' #"8 e+te i'+tit&to ,orm! 1!rte el 1ro9e(to EUREA EU#8 RADIODIFUSIN DE AUDIO DIGITAL8 9 em1iez! ! e+!rroll!r i'.e+ti%!(io'e+ +obre (oi)(!(i' e !&io 1er(e1t&!l/ E' (oo1er!(i' (o';&'t! (o' l! U'i.er+i! e Erl!'%e' 6el 1ro,e+or Dieter Seitzer78 el i'+tit&to Fr!&'-o,er )'!lme'te ie &' !l%oritmo m&9 1oero+o *&e +e (o'.irti e' e+t2'!r i'ter'!(io'!l (omo ISOIEC MPEG A&io8 C!1! III 6ISOIEC ###$> 38 C!1! III7/ E' l! +i%&ie'te t!bl! +e m&e+tr!' !l%&'o+ !to+ el e+em1eo e e+te !l%oritmo )

 ! *&e 5+t! e+ l! (!1! *&e (orre+1o'e !l ,orm!to MP38 +e i'te't!r2 !r &'! me;or e+(ri1(i' e l! m!'er! e' *&e +e re!liz! el 1ro(e+o 1!r! %e'er!r &;o+ e !&io MP3 .2lio+/ E' l! +i%&ie'te )%&r! +e m&e+tr! &' i!%r!m! e' blo*&e+ m2+ et!ll!o el (oi)(!or 1+i(o!(,9>,98>  >educcion:9,98,?S,A,MAP  +, scalefacscale:)r<  +F scalefacl:1,)r<  -eros:2#,#