lagcount := 0

  for j := 0 to 3 do
  begin
    smallag := maximum(Nj,N{j-1}) mod minimum(Nj,N{j-1})
    if minimum(smallag,minimum(Nj,N{j-1})-smallag) < lthresh
      then increment(lagcount)
  end

  veryoldlagcount := oldlagcount

  oldlagcount := lagcount

	tone := false
	
	den := a[1]*a[1]
	num := 4*a[2] - a[1]*a[1]

	if ( num <= 0 ) 
	  return

	if (( a[1] < 0 ) AND ( num / den < freqth ))
	  return
	            4
	prederr := MULT (1 - RC[i]*RC[i])
	           i=1

	if (prederr < predth)
	  tone := true

	return

	vvad := pvad > thvad

  if vvad then increment(burstcount) else burstcount := 0

  if burstcount >= burstconst then
  begin
    hangcount := hangconst;
    burstcount := burstconst
  end

  vad := vvad or (hangcount >= 0)

  if hangcount >= 0 then decrement(hangcount)

IF ( scalauto < 0 ) THEN scalvad = 0;
ELSE scalvad = scalauto;  / keep scalvad for use in subclause 3.2 /

IF ( L_ACF[0] == 0 ) THEN
						| e_pvad = -32768;
						| m_pvad = 0;
						| e_acf0 = -32768;
						| m_acf0 = 0;
						| EXIT  /continue with subclause 3.2/


normacf = norm( L_ACF[0] );

| FOR i = 0 to 8:
|  sacf[i] = ( L_ACF[i] << normacf ) >> 19;
| NEXT i:


e_acf0 = add( 32, (scalvad << 1 ) );
e_acf0 = sub( e_acf0, normacf);
m_acf0 = sacf[0] << 3;


e_pvad = add( e_acf0, 14 );
e_pvad = sub( e_pvad, normrvad );

L_temp = 0;

| FOR i = 1 to 8:
|  L_temp = L_add( L_temp, L_mult( sacf[i], rvad[i] ) );
| NEXT i:

L_temp = L_add( L_temp, L_mult( sacf[0], rvad[0] ) >> 1 );

IF ( L_temp <= 0 ) THEN L_temp = 1;

normprod = norm( L_temp );
e_pvad = sub( e_pvad, normprod );
m_pvad = ( L_temp << normprod ) >> 16;


scal = sub( 10, (scalvad << 1) );


| FOR i = 0 to 8:
|  L_temp = L_ACF[i] >> scal;
|  L_av0[i] = L_add( L_sacf[i], L_temp );
|  L_av0[i] = L_add( L_sacf[i+9], L_av0[i] );
|  L_av0[i] = L_add( L_sacf[i+18], L_av0[i] );
|  L_sacf[ pt_sacf + i ] = L_temp;
|  L_av1[i] = L_sav0[ pt_sav0 + i ];
|  L_sav0[ pt_sav0 + i] = L_av0[i];
| NEXT i:


IF ( pt_sacf == 18 ) THEN pt_sacf = 0;
ELSE pt_sacf = add( pt_sacf, 9);

IF ( pt_sav0 == 27 ) THEN pt_sav0 = 0;
ELSE pt_sav0 = add( pt_sav0, 9);


IF( L_av1[0] == 0 ) THEN
                         |== FOR i = 1 to 8:
                         |    vpar[i] = 0;
                         |== NEXT i:
                         |    EXIT; /continue with subclause 3.3.2/
temp = norm( L_av1[0] );
|== FOR k=0 to 8:
|    sacf[k] = ( L_av1[k] << temp ) >> 16;
|== NEXT k:


|== FOR i=1 to 7:
|    K[9-i] = sacf[i];
|== NEXT i:

|== FOR i=0 to 8:
|    P[i] = sacf[i];
|== NEXT i:


|== FOR n=1 to 8:
|    IF( P[0] < abs( P[1] ) ) THEN
|                                    |== FOR i = n to 8:
|                                    |    vpar[i] = 0;
|                                    |== NEXT i:
|                                    | EXIT; /continue with
|                                    |        subclause 3.3.2/
|    vpar[n] = div( abs( P[1] ), P[0] );
|    IF ( P[1] > 0 ) THEN vpar[n] = sub( 0, vpar[n] );
|    IF ( n == 8 ) THEN EXIT; /continue with subclause 3.3.2/
|
|  Schur recursion:
|
|    P[0] = add( P[0], mult_r( P[1], vpar[n] ) );
|==== FOR m=1 to 8-n:
|      P[m] = add( P[m+1], mult_r( K[9-m], vpar[n] ) );
|      K[9-m] = add( K[9-m], mult_r( P[m+1], vpar[n] ) );
|==== NEXT m:
|
|== NEXT n:


L_coef[0] = 16384 << 15;
L_coef[1] = vpar[1] << 14;


|= FOR m = 2 to 8:
|== FOR i = 1 to m-1:
|==  temp = L_coef[m-i] >> 16;  / takes the msb /
|==  L_work[i] = L_add( L_coef[i], L_mult( vpar[m], temp ) );
|== NEXT i
|=
|== FOR i = 1 to m-1:
|==  L_coef[i] = L_work[i];
|== NEXT i
|=
|= L_coef[m] = vpar[m] << 14;
|= NEXT m:


| FOR i = 0 to 8:
|  aav1[i] = L_coef[i] >> 19;
| NEXT i:

|= FOR i= 0 to 8:
|= L_work[i] = 0;
|== FOR k = 0 to 8-i:
|==  L_work[i] = L_add( L_work[i], L_mult( aav1[k], aav1[k+i] ) );
|== NEXT k:
|= NEXT i:

IF ( L_work[0] == 0 ) THEN normrav1 =0;
ELSE normrav1 = norm( L_work[0] );

|= FOR i= 0 to 8:
|= rav1[i] = ( L_work[i] << normrav1 ) >> 16;
|= NEXT i:

Keep the normrav1 for use in subclause 3.4 and 3.6.


IF ( L_av0[0] == 0 ) THEN
                          | FOR i = 0 to 8:
                          |  sav0[i] = 4095;
                          | NEXT i:
ELSE
    | shift = norm( L_av0[0] );
    |= FOR i = 0 to 8:
    |=  sav0[i] = ( L_av0[i] << shift-3 ) >> 16;
    |= NEXT i:

L_ S p = 0;
|= FOR i = 1 to 8:
|= L_ S p = L_add( L_ S p, L_mult( rav1[i], sav0[i] ) );
|= NEXT i:


IF ( L_ S p < 0 ) THEN L_temp = L_sub( 0, L_ S p );
ELSE L_temp = L_ S p;

IF ( L_temp == 0 ) THEN
                       | L_dm  = 0;
                       | shift = 0;
ELSE
     | sav0[0] = sav0[0] << 3;
     | shift = norm( L_temp );
     | temp  = ( L_temp << shift ) >> 16;
     | IF ( sav0[0] >= temp ) THEN
     |                            | divshift = 0;
     |                            | temp = div( temp, sav0[0] );
     | ELSE
     |     | divshift = 1;
     |     | temp = sub( temp, sav0[0] );
     |     | temp = div( temp, sav0[0] );
     |
     | IF( divshift == 1 ) THEN L_dm = 32768;
     | ELSE L_dm = 0;
     |
     | L_dm = L_add( L_dm, temp) << 1;
     | IF( L_ S p < 0 ) THEN L_dm = L_sub( 0,  L_dm);


L_dm = ( L_dm << 14 );
L_dm = L_dm >> shift;
L_dm = L_add( L_dm, ( rav1[0] << 11 ) );
L_dm = L_dm >> normrav1;


L_temp   = L_sub( L_dm, L_lastdm );
L_lastdm = L_dm;
IF ( L_temp < 0 ) THEN L_temp = L_sub( 0, L_temp );
L_temp = L_sub( L_temp, 3277 );


IF ( L_temp < 0 ) THEN stat = 1;
ELSE stat = 0;

temp = add( oldlagcount, veryoldlagcount );
IF ( temp >= 4 ) THEN ptch = 1;
ELSE ptch = 0;

comp = 0;
IF ( e_acf0 < E_PTH ) THEN  comp = 1;
IF ( e_acf0 == E_PTH ) THEN  IF ( m_acf0 < M_PTH ) THEN comp =1;
IF ( comp == 1 ) THEN
                      | e_thvad = E_PLEV;
                      | m_thvad = M_PLEV;
                      | EXIT; /continue with subclause 3.7/


comp = 0;
IF ( ptch == 1 ) THEN comp = 1;
IF ( stat == 0 ) THEN comp = 1;
IF ( tone == 1 ) THEN comp = 1;
IF ( comp == 1 ) THEN
                      | adaptcount = 0;
                      | EXIT; /continue with subclause 3.7/


adaptcount = add( adaptcount, 1 );
IF ( adaptcount <= 8 ) THEN EXIT; /continue with subclause 3.7/


m_thvad = sub( m_thvad, (m_thvad >> 5 ) );
IF ( m_thvad < 16384) THEN
                           | m_thvad = m_thvad << 1;
                           | e_thvad = sub( e_thvad, 1 );


L_temp = L_add( m_pvad, m_pvad );
L_temp = L_add( L_temp, m_pvad );
L_temp = L_temp >> 1;
e_temp = add( e_pvad, 1 );
IF ( L_temp > 32767 ) THEN
                          | L_temp = L_temp >> 1;
                          | e_temp = add( e_temp, 1 );
m_temp = L_temp;


comp = 0;
IF ( e_thvad < e_temp) THEN comp = 1;
IF (e_thvad == e_temp) THEN  IF (m_thvad < m_temp) THEN comp =1;


IF ( comp == 1 ) THEN
|  Compute thvad +(thvad/inc).
| L_temp = L_add( m_thvad, (m_thvad >> 4 ) );
| IF ( L_temp > 32767 ) THEN
|                           | m_thvad = L_temp >> 1;
|                           | e_thvad = add( e_thvad,1 );
| ELSE m_thvad = L_temp;
| comp2 = 0;
| IF ( e_temp < e_thvad) THEN comp2 = 1;
| IF (e_temp == e__hvad) THEN IF (m_temp<m_thvad) THEN comp2 = 1;
| IF ( comp2 == 1 ) THEN
|                        | e_thvad = e_temp;
|                        | m_thvad = m_temp;


IF ( e_pvad == E_MARGIN ) THEN
                               | L_temp = L_add(m_pvad, M_MARGIN);
                               | m_temp = L_temp >> 1;
                               | e_temp = add( e_pvad, 1 );
ELSE
    | IF ( e_pvad > E_MARGIN ) THEN
    |     | temp = sub( e_pvad, E_MARGIN );
    |     | temp = M_MARGIN >> temp;
    |     | L_temp = L_add( m_pvad, temp );
    |     | IF ( L_temp > 32767) THEN
    |     |                           | e_temp = add( e_pvad, 1 );
    |     |                           | m_temp = L_temp >> 1;
    |     | ELSE
    |     |    | e_temp = e_pvad;
    |     |    | m_temp = L_temp;
    | ELSE
    |     | temp = sub( E_MARGIN, e_pvad );
    |     | temp = m_pvad >> temp;
    |     | L_temp = L_add( M_MARGIN, temp );
    |     | IF (L_temp > 32767) THEN
    |     |                          | e_temp = add( E_MARGIN, 1);
    |     |                          | m_temp = L_temp >> 1;
    |     | ELSE
    |     |    | e_temp = E_MARGIN;
    |     |    | m_temp = L_temp;


comp = 0;
IF ( e_thvad > e_temp) THEN comp = 1;
IF (e_thvad == e_temp) THEN  IF (m_thvad > m_temp) THEN comp =1;

IF ( comp == 1 ) THEN
                      | e_thvad = e_temp;
                      | m_thvad = m_temp;


normrvad  = normrav1;

|= FOR i = 0 to 8:
|= rvad[i] = rav1[i];
|= NEXT i:


adaptcount = 9;

vvad = 0;
IF (e_pvad >  e_thvad) THEN vvad = 1;
IF (e_pvad == e_thvad) THEN IF (m_pvad > m_thvad) THEN vvad =1;

IF ( vvad == 1 ) THEN burstcount = add( burstcount, 1 );
ELSE burstcount = 0;

IF ( burstcount >= 3 ) THEN 
                            | hangcount =  5;
                            | burstcount = 3;

vad = vvad;
IF ( hangcount >= 0 ) THEN
                           | vad = 1;
                           | hangcount = sub( hangcount, 1 );


lagcount = 0;

|= FOR i = 0 to 3:
|=  Search the maximum and minimum of consecutive lags.
|= IF ( oldlag > lags[i] ) THEN
|=                              | minlag = lags[i];
|=                              | maxlag = oldlag;
|= ELSE
|=      | minlag = oldlag;
|=      | maxlag = lags[i] ;
|=
|= Compute smallag (modulo operation not defined ):
|=
|= smallag = maxlag;
|== | FOR j = 0 to 2:
|== |  IF (smallag >= minlag) THEN smallag =sub( smallag, minlag);
|== | NEXT j;
|=
|= Minimum of smallag and minlag - smallag:
|=
|= temp = sub( minlag, smallag );
|= IF ( temp < smallag ) THEN smallag = temp;
|= IF ( smallag < 2 ) THEN lagcount = add( lagcount, 1 );
|= Save the current LTP lag.
|= oldlag = lags[i];
|= NEXT i:


veryoldlagcount = oldlagcount;
oldlagcount     = lagcount;

|== FOR i = 0 to 79:
|    sofh[i] = mult_r( sof[i], hann[i] );
|    sofh[159-i] = mult_r( sof[159-i], hann[i] );
|== NEXT i;


smax = 0;

|== FOR k = 0 to 159:
|    temp = abs( sofh[k] );
|    IF ( temp > smax ) THEN smax = temp;
|== NEXT k;

IF ( smax == 0 ) THEN scalauto = 0;
ELSE scalauto = sub( 4, norm( smax << 16));


IF ( scalauto > 0 ) THEN
                        | temp = 16384 >> sub( scalauto,1);
                        |== FOR k = 0 to 159:
                        |    sofh[k] = mult_r( sofh[k], temp);
                        |== NEXT k:


|== FOR k=0 to 4:
|    L_acfh[k] = 0;
|==== FOR i=k to 159:
|      L_temp = L_mult( sofh[i], sofh[i-k] );
|      L_acfh[k] = L_add( L_acfh[k], L_temp );
|==== NEXT i:
|== NEXT k:


IF( L_acfh[0] == 0 ) THEN
                         |== FOR i = 1 to 4:
                         |    rc[i] = 0;
                         |== NEXT i:
                         | EXIT; /continue with subclause 3.10.4/
temp = norm( L_acfh[0] );
|== FOR k=0 to 4:
|    sacf[k] = ( L_acfh[k] << temp ) >> 16;
|== NEXT k:


|== FOR i=1 to 3:
|    K[5-i] = sacf[i];
|== NEXT i:

|== FOR i=0 to 4:
|    P[i] = sacf[i];
|== NEXT i:

|== FOR n=1 to 4:
|    IF( P[0] < abs( P[1] ) ) THEN
|                                    |== FOR i = n to 4:
|                                    |    rc[i] = 0;
|                                    |== NEXT i:
|                                    | EXIT; /continue with subclause 3.10.4/
|    rc[n] = div( abs( P[1] ), P[0] );
|    IF ( P[1] > 0 ) THEN rc[n] = sub( 0, rc[n] );
|    IF ( n == 4 ) THEN EXIT; /continue with subclause 3.10.4/
|
|
|    P[0] = add( P[0], mult_r( P[1], rc[n] ) );
|==== FOR m=1 to 4-n:
|      P[m] = add( P[m+1], mult_r( K[5-m], rc[n] ) );
|      K[5-m] = add( K[5-m], mult_r( P[m+1], rc[n] ) );
|==== NEXT m:
|
|== NEXT n:


temp = rc[1] >> 2;  
a[1] = add( temp, mult_r( rc[2], temp ) );
a[2] = rc[2] >> 2;

L_den = L_mult ( a[1], a[1] );

L_temp = a[2] << 16;
L_num = L_sub ( L_temp, L_den );


IF ( L_num <= 0 ) THEN 
                      | tone = 0;
                      | EXIT; /clause 3 complete/


IF ( a[1] < 0) THEN
                     | temp = L_den >> 16;
                     | L_den = L_mult ( temp, 3189 );
                     | L_temp = L_sub ( L_num, L_den );
                     | IF ( L_temp < 0 ) THEN
                                             | tone = 0;
                                             | EXIT; /clause 3 complete/


prederr = 32767;

|== FOR i=1 to 4
|    temp = mult ( rc[i], rc[i] );
|    temp = sub ( 32767, temp);
|    prederr = mult( prederr, temp );
|== NEXT i;


temp = sub ( prederr, 1464 );

IF ( temp < 0 ) THEN tone = 1;
 ELSE tone = 0;

    LAR(1): bit 15 := 1 if VAD on
            bit 15 := 0 if VAD 0ff


    LAR(2): bit 15 := 1 if SP on
            bit 15 := 0 if SP off


| FOR i = 1 to 8:
|  L_Temp = 2;	/* const. for rounding*/
|  | FOR n = 1 to 4:
|  |  L_Temp1 = LAR[j-n](i);	/*conversion 16 --> 32 bit*/
|  |  L_Temp  = L_Add( L_Temp , L_Temp1 );
|  | NEXT n
|  L_Temp = L_temp >> 2; 
|  mean (LAR(i)) = L_Temp;	/*conversion 32 --> 16 bit*/
| NEXT i;



L_Temp = 8;	/* const. for rounding*/

| FOR n = 1 to 4:
|  | FOR i = 1 to 4:
|  |  L_Temp1 = xmax[j-n](i);	/*conversion 16 --> 32 bit*/
|  |  L_Temp  = L_Add( L_Temp , L_Temp1 );
|  | NEXT i
| NEXT n

L_Temp = L_Temp >> 4;

mean (xmax) = L_Temp;	/*conversion 32 --> 16 bit*/


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ETS 300 965 (GSM 06.32 version 5.0.3): March 1998

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ETS 300 965 (GSM 06.32 version 5.0.3): March 1998