voicin.f,v

lpc10-15为美军2400bps语音压缩标准的C语音源代码。

*	In the following chart, the decisions marked with a * may be overridden.
*
*   Voicing override of transitions at onsets:
*	If a V/UV or UV/V voicing decision transition occurs within one-half
*	frame of an onset bounding a voicing window, then the transition is
*	moved to occur at the onset.
*
*	P	1F
*	-----	-----
*	0   0   0   0
*	0   0   0*  1	(If there is an onset there)
*	0   0   1*  0*	(Based on 2F and discriminant distance)
*	0   0   1   1
*	0   1*  0   0	(Always)
*	0   1*  0*  1	(Based on discriminant distance)
*	0*  1   1   0*	(Based on past, 2F, and discriminant distance)
*	0   1*  1   1	(If there is an onset there)
*	1   0*  0   0	(If there is an onset there)
*	1   0   0   1
*	1   0*  1*  0	(Based on discriminant distance)
*	1   0*  1   1	(Always)
*	1   1   0   0
*	1   1   0*  1*	(Based on 2F and discriminant distance)
*	1   1   1*  0	(If there is an onset there)
*	1   1   1   1
*
*   Determine if there is an onset transition between P and 1F.
*   OT (Onset Transition) is true if there is an onset between 
*   P and 1F but not after 1F.

	OT = (AND(OBOUND(1), 2) .NE. 0 .OR. OBOUND(2) .EQ. 1)
     1      .AND. AND(OBOUND(3), 1) .EQ. 0

*   Multi-way dispatch on voicing decision history:

	VSTATE = VOIBUF(1,1)*8 + VOIBUF(2,1)*4 + VOIBUF(1,2)*2 + VOIBUF(2,2)
	GOTO (99,1,2,99,4,5,6,7,8,99,10,11,99,13,14,99) VSTATE+1

1	   IF (OT .AND. VOIBUF(1,3) .EQ. 1) VOIBUF(1,2) = 1
	GOTO 99

2	   IF (VOIBUF(1,3) .EQ. 0 .OR.
     1    VOICE(1,2) .LT. -VOICE(2,2)) THEN
	      VOIBUF(1,2) = 0
	   ELSE
	      VOIBUF(2,2) = 1
	   END IF
	GOTO 99

4	   VOIBUF(2,1) = 0
	GOTO 99

5	   IF (VOICE(2,1) .LT. -VOICE(1,2)) THEN
	      VOIBUF(2,1) = 0
	   ELSE
	      VOIBUF(1,2) = 1
	   END IF
	GOTO 99

*   VOIBUF(2,0) must be 0
6	   IF (VOIBUF(1,0) .EQ. 1 .OR.
     1         VOIBUF(1,3) .EQ. 1 .OR.
     1          VOICE(2,2) .GT. VOICE(1,1)) THEN
	      VOIBUF(2,2) = 1
	   ELSE
	      VOIBUF(1,1) = 1
	   END IF
	GOTO 99

7	   IF (OT) VOIBUF(2,1) = 0
	GOTO 99

8	   IF (OT) VOIBUF(2,1) = 1
	GOTO 99

10	   IF (VOICE(1,2) .LT. -VOICE(2,1)) THEN
	      VOIBUF(1,2) = 0
	   ELSE
	      VOIBUF(2,1) = 1
	   END IF
	GOTO 99

11	   VOIBUF(2,1) = 1
	GOTO 99

13	   IF (VOIBUF(1,3) .EQ. 0 .AND. VOICE(2,2) .LT. -VOICE(1,2)) THEN
	      VOIBUF(2,2) = 0
	   ELSE
	      VOIBUF(1,2) = 1
	   END IF
	GOTO 99

14	   IF (OT .AND. VOIBUF(1,3) .EQ. 0) VOIBUF(1,2) = 0
*	GOTO 99

99	CONTINUE

*   Now update parameters:
*   ----------------------
*
*   During unvoiced half-frames, update the low band and full band unvoiced
*   energy estimates (LBUE and FBUE) and also the zero crossing
*   threshold (DITHER).  (The input to the unvoiced energy filters is
*   restricted to be less than 10dB above the previous inputs of the
*   filters.)
*   During voiced half-frames, update the low-pass (LBVE) and all-pass 
*   (FBVE) voiced energy estimates.

	IF (VOIBUF(HALF,3) .EQ. 0) THEN
	   SFBUE = NINT(( 63*SFBUE + 8*MIN(FBE,3*OFBUE) )/64.)
	   FBUE = SFBUE/8
	   OFBUE = FBE
	   SLBUE = NINT(( 63*SLBUE + 8*MIN(LBE,3*OLBUE) )/64.)
	   LBUE = SLBUE/8
	   OLBUE = LBE
	ELSE
	   LBVE = NINT(( 63*LBVE + LBE )/64.)
	   FBVE = NINT(( 63*FBVE + FBE )/64.)
	END IF

*   Set dither threshold to yield proper zero crossing rates in the
*   presence of low frequency noise and low level signal input.
*   NOTE: The divisor is a function of REF, the expected energies.

	DITHER = MIN(MAX( 64*SQRT(FLOAT(LBUE*LBVE)) / REF,1.),20.)

*   Print Test Data

*	IF( LISTL.GE.3 ) THEN
*	   IF(HALF.EQ.1) WRITE(FDEBUG,930) VWIN,MINAMD,MAXAMD,MINTAU,IVRC
*930	   FORMAT(' Voicing:VWIN     MINA     MAXA  MINTAU  IVRC1  IVRC2'/
*     1    5X,2I4,2F9.1,I8,2F7.3/
*     1    ' HALF  DISCR  MAX/MIN  LE/LVE   ZC    RC1     QS   IVRC2'
*     1    '   aR_B   aR_F : DITH  LBE   FBE  LBVE  FBVE  LBUE  FBUE',
*     1    '     SNR SNRL VS OT')
*	   WRITE(FDEBUG,940) HALF, VOICE(HALF,3), (VALUE(I),I=1,8), DITHER,
*     1    LBE, FBE, LBVE, FBVE, LBUE, FBUE,
*     1    SNR, SNRL, VSTATE, OT
*940	   FORMAT(1X,I3,':',F8.0,F9.1,F7.3,F7.2,5F7.3,F5.1,6I6,F9.1,2I3,L3)
*	END IF

*   Voicing decisions are returned in VOIBUF.

	RETURN


	ENTRY INITVOICIN ()

	FIRST = .TRUE.
	DITHER = 20

	RETURN

	END
@


1.9
log
@Added a few comments about the accesses made to argument array VOIBUF
and the local saved array VOICE.
@
text
@d6 4
d380 1
a380 1
	DO I = 1, 9
@


1.8
log
@Added an assignment to VSTATE that does not affect the function of the
program at all.  The only reason I put it in was so that the tracing
statements at the end, when enabled, will print a consistent value for
VSTATE when HALF .EQ. 1, rather than a garbage value that could change
from one call to the next.
@
text
@d6 7
d113 1
d116 1
a116 1
*                 read (1,3) and write (1,2)
d121 2
a122 1
*              Read (HALF,3)
d138 5
@


1.7
log
@Removed the inclusion of the file "vcomm.fh", and put its contents
into this file.  It was included nowhere else but here.
@
text
@d6 4
d377 7
d531 1
a531 1
*     1    ' SNR SNRL VS OT')
d535 1
a535 1
*940	   FORMAT(1X,I3,':',F8.0,F9.1,F7.3,F7.2,5F7.3,F5.1,6I6,F5.1,2I3,L3)
@


1.6
log
@Commented out trace statements.
@
text
@d6 3
d169 13
a181 1
	INCLUDE 'vcomm.fh'
a260 11
*       The following data statements initialize variables declared in
*       vcomm.fh (which is used nowhere else except this subroutine).
*       They are not Fortran PARAMETER's, but they are initialized with
*       DATA statements, and never modified.

	DATA NVDC/10/, NVDCL/5/
	DATA VDCL/600,450,300,200,6*0/

*       The array VDC is not a Fortran PARAMETER, but it is an array
*       that is initialized with DATA statements, and never modified.

d285 3
@


1.5
log
@Added comments about which indices of OBOUND and VOIBUF can be
accessed, and whether they are read or written.  VOIBUF is fairly
messy.
@
text
@d6 5
d507 12
a518 12
	IF( LISTL.GE.3 ) THEN
	   IF(HALF.EQ.1) WRITE(FDEBUG,930) VWIN,MINAMD,MAXAMD,MINTAU,IVRC
930	   FORMAT(' Voicing:VWIN     MINA     MAXA  MINTAU  IVRC1  IVRC2'/
     1    5X,2I4,2F9.1,I8,2F7.3/
     1    ' HALF  DISCR  MAX/MIN  LE/LVE   ZC    RC1     QS   IVRC2'
     1    '   aR_B   aR_F : DITH  LBE   FBE  LBVE  FBVE  LBUE  FBUE',
     1    ' SNR SNRL VS OT')
	   WRITE(FDEBUG,940) HALF, VOICE(HALF,3), (VALUE(I),I=1,8), DITHER,
     1    LBE, FBE, LBVE, FBVE, LBUE, FBUE,
     1    SNR, SNRL, VSTATE, OT
940	   FORMAT(1X,I3,':',F8.0,F9.1,F7.3,F7.2,5F7.3,F5.1,6I6,F5.1,2I3,L3)
	END IF
@


1.4
log
@Moved the DATA statements for the *VDC* variables later, as it is
apparently illegal to have DATA statements before local variable
declarations.
@
text
@d6 5
d89 1
d93 9
@


1.3
log
@Heavily commented the local variables that are saved from one
invocation to the next, and how the local variable FIRST is used to
avoid the need to assign most of them initial values with DATA
statements.

A few should be initialized, but aren't.  I've guessed initial values
for two of these, SFBUE and SLBUE, and I've convinced myself that for
VOICE, the effects of uninitialized values will die out after 2 or 3
frame times.  It would still be good to choose initial values for
these, but I don't know what reasonable values would be (0 comes to
mind).
@
text
@d6 13
a147 36
*       The following data statements initialize variables declared in
*       vcomm.fh (which is used nowhere else except this subroutine).
*       They are not Fortran PARAMETER's, but they are initialized with
*       DATA statements, and never modified.

	DATA NVDC/10/, NVDCL/5/
	DATA VDCL/600,450,300,200,6*0/

*       The array VDC is not a Fortran PARAMETER, but it is an array
*       that is initialized with DATA statements, and never modified.

*   Voicing Decision Parameter vector (* denotes zero coefficient):
*
*	* MAXMIN
*	  LBE/LBVE
*	  ZC
*	  RC1
*	  QS
*	  IVRC2
*	  aR_B
*	  aR_F
*	* LOG(LBE/LBVE)

*   Define 2-D voicing decision coefficient vector according to the voicing
*   parameter order above.  Each row (VDC vector) is optimized for a specific
*   SNR.  The last element of the vector is the constant.

*	         E    ZC    RC1    Qs   IVRC2  aRb   aRf        c
	DATA VDC/
     1     0, 1714, -110,  334, -4096,  -654, 3752, 3769, 0,  1181,
     1     0,  874,  -97,  300, -4096, -1021, 2451, 2527, 0,  -500,
     1     0,  510,  -70,  250, -4096, -1270, 2194, 2491, 0, -1500,
     1     0,  500,  -10,  200, -4096, -1300, 2000, 2000, 0, -2000,
     1     0,  500,    0,    0, -4096, -1300, 2000, 2000, 0, -2500,
     1     50*0/

d225 36
@


1.2
log
@Comments added explaining which of the local variables of this
subroutine need to be saved from one invocation to the next, and which
do not.

WARNING!  Some of them that should are never given initial values in
this code.  Hopefully, Fortran 77 defines initial values for them, but
even so, giving them explicit initial values is preferable.

WARNING!  VALUE(9) is used, but never assigned a value.  It should
probably be eliminated from the code.
@
text
@d6 12
d56 54
a109 46
*  Inputs:
*   VWIN      - Voicing window limits
*   INBUF     - Input speech buffer
*   LPBUF     - Low-pass filtered speech buffer
*   BUFLIM    - INBUF and LPBUF limits
*   HALF      - Present analysis half frame number
*   MINAMD    - Minimum value of the AMDF
*   MAXAMD    - Maximum value of the AMDF
*   MINTAU    - Pointer to the lag of the minimum AMDF value
*   IVRC(2)   - Inverse filter's RC's
*   OBOUND    - Onset boundary descriptions
*   AF        - The analysis frame number
*  Output:
*   VOIBUF(2,0:AF) - Buffer of voicing decisions
*  Internal:
*   QS        - Ratio of preemphasized to full-band energies
*   RC1       - First reflection coefficient
*   AR_B      - Product of the causal forward and reverse pitch prediction gains
*   AR_F      - Product of the noncausal forward and rev. pitch prediction gains
*   ZC        - Zero crossing rate
*   DITHER    - Zero crossing threshold level
*   MAXMIN    - AMDF's 1 octave windowed maximum-to-minimum ratio
*   MINPTR    - Location  of minimum AMDF value
*   NVDC      - Number of elements in each VDC vector
*   NVDCL     - Number of VDC vectors
*   VDCL      - SNR values corresponding to the set of VDC's
*   VDC       - 2-D voicing decision coefficient vector
*   VALUE(9)  - Voicing Parameters
*   VOICE(2,3)- History of LDA results
*   LBE       - Ratio of low-band instantaneous to average energies
*   FBE       - Ratio of full-band instantaneous to average energies
*   LBVE      - Low band voiced energy
*   LBUE      - Low band unvoiced energy
*   FBVE      - Full band voiced energy
*   FBUE      - Full band unvoiced energy
*   OFBUE     - Previous full-band unvoiced energy
*   OLBUE     - Previous low-band unvoiced energy
*   REF       - Reference energy for initialization and DITHER threshold
*   SNR       - Estimate of signal-to-noise ratio
*   SNR2      - Estimate of low-band signal-to-noise ratio
*   SNRL      - SNR level number
*   OT        - Onset transition present
*   VSTATE    - Decimal interpretation of binary voicing classifications
*   FIRST     - First call flag


a115 1
	INCLUDE 'vcomm.fh'
d117 1
a117 1
*       Parameters
d128 1
a128 1
*       Local variables
d130 2
a131 7
	INTEGER ZC, LBE, FBE
	INTEGER I, SNRL, VSTATE
	REAL DITHER, SNR, SNR2
	REAL MAXMIN, QS, RC1, AR_B, AR_F
	REAL VOICE(2,3)
	REAL VALUE(9)
	LOGICAL OT
d133 1
a133 6
*       NO SAVE NECESSARY  ZC, LBE, FBE
*       NO SAVE NECESSARY  I, SNRL, VSTATE
*       NO SAVE NECESSARY  SNR2
*       NO SAVE NECESSARY  QS, RC1, AR_B, AR_F
*       NO SAVE NECESSARY  VALUE
*       NO SAVE NECESSARY  OT
d135 4
a138 3
	SAVE DITHER, SNR
	SAVE MAXMIN
	SAVE VOICE
d140 1
a140 26
*       WARNING!
*       
*       VOICE, SFBUE, and SLBUE should be saved from one invocation to
*       the next, but they are never given an initial value, like all of
*       the other local variables that should similarly be saved.
*       
*       Does Fortran 77 specify some default initial value, like 0, or
*       is it undefined?  If it is undefined, then this code should be
*       corrected to specify an initial value.
*       
*       Also, while VALUE(1) through VALUE(8) are assigned values,
*       VALUE(9) never is.  Yet, VALUE(9) is read in the loop that
*       begins "DO I = 1, 9" below.  If this value is automatically
*       initialized to 0, then it has no detrimental effect, but if it
*       is undefined, it could have an unpredictable and detrimental
*       effect on the behavior of this code.  I would recommend changing
*       the loop to "DO I = 1, 8".

*   Declare and initialize filters:

	INTEGER LBVE, LBUE, FBVE, FBUE, OFBUE, OLBUE, SFBUE, SLBUE
	INTEGER REF
	PARAMETER (REF = 3000)

	LOGICAL FIRST
	DATA FIRST /.TRUE./, DITHER/20/, NVDC/10/, NVDCL/5/
d143 2
a144 2
	SAVE LBVE, LBUE, FBVE, FBUE, OFBUE, OLBUE, SFBUE, SLBUE
	SAVE FIRST
d171 79
d255 1
d258 1
d490 9
@


1.1
log
@Initial revision
@
text
@d5 4
a8 1
* $Log$
d98 3
a100 3
	REAL MINAMD, MAXAMD
	INTEGER VWIN(2), BUFLIM(4), HALF, MINTAU
	INTEGER AF, OBOUND(AF)
d103 8
a110 1
	INTEGER VOIBUF(2,0:AF)
d113 2
a114 3
	REAL DITHER, SNR, SNR2, IVRC(2)
	REAL MAXMIN, QS, RC1, AR_B
	REAL AR_F
d119 29
d157 3
@