analys.c
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- /*
- $Log: analys.c,v $
- Revision 1.1.1.1 2002/07/28 05:23:15 freeman_yong
- lpc10 codec
- * Revision 1.2 1996/08/20 20:16:01 jaf
- * Removed all static local variables that were SAVE'd in the Fortran
- * code, and put them in struct lpc10_encoder_state that is passed as an
- * argument.
- *
- * Removed init function, since all initialization is now done in
- * init_lpc10_encoder_state().
- *
- * Revision 1.1 1996/08/19 22:29:08 jaf
- * Initial revision
- *
- */
- #ifdef P_R_O_T_O_T_Y_P_E_S
- extern int analys_(real *speech, integer *voice, integer *pitch, real *rms, real *rc, struct lpc10_encoder_state *st);
- /* comlen contrl_ 12 */
- /*:ref: preemp_ 14 5 6 6 4 6 6 */
- /*:ref: onset_ 14 7 6 4 4 4 4 4 4 */
- /*:ref: placev_ 14 11 4 4 4 4 4 4 4 4 4 4 4 */
- /*:ref: lpfilt_ 14 4 6 6 4 4 */
- /*:ref: ivfilt_ 14 5 6 6 4 4 6 */
- /*:ref: tbdm_ 14 8 6 4 4 4 6 4 4 4 */
- /*:ref: voicin_ 14 12 4 6 6 4 4 6 6 4 6 4 4 4 */
- /*:ref: dyptrk_ 14 6 6 4 4 4 4 4 */
- /*:ref: placea_ 14 9 4 4 4 4 4 4 4 4 4 */
- /*:ref: dcbias_ 14 3 4 6 6 */
- /*:ref: energy_ 14 3 4 6 6 */
- /*:ref: mload_ 14 6 4 4 4 6 6 6 */
- /*:ref: invert_ 14 4 4 6 6 6 */
- /*:ref: rcchk_ 14 3 4 6 6 */
- /*:ref: initonset_ 14 0 */
- /*:ref: initvoicin_ 14 0 */
- /*:ref: initdyptrk_ 14 0 */
- /* Rerunning f2c -P may change prototypes or declarations. */
- #endif
- /* -- translated by f2c (version 19951025).
- You must link the resulting object file with the libraries:
- -lf2c -lm (in that order)
- */
- #include "f2c.h"
- /* Common Block Declarations */
- extern struct {
- integer order, lframe;
- logical corrp;
- } contrl_;
- #define contrl_1 contrl_
- /* Table of constant values */
- static integer c__10 = 10;
- static integer c__181 = 181;
- static integer c__720 = 720;
- static integer c__3 = 3;
- static integer c__90 = 90;
- static integer c__156 = 156;
- static integer c__307 = 307;
- static integer c__462 = 462;
- static integer c__312 = 312;
- static integer c__60 = 60;
- static integer c__1 = 1;
- /* ****************************************************************** */
- /* ANALYS Version 55 */
- /* $Log: analys.c,v $
- /* Revision 1.1.1.1 2002/07/28 05:23:15 freeman_yong
- /* lpc10 codec
- /*
- * Revision 1.2 1996/08/20 20:16:01 jaf
- * Removed all static local variables that were SAVE'd in the Fortran
- * code, and put them in struct lpc10_encoder_state that is passed as an
- * argument.
- *
- * Removed init function, since all initialization is now done in
- * init_lpc10_encoder_state().
- *
- * Revision 1.1 1996/08/19 22:29:08 jaf
- * Initial revision
- * */
- /* Revision 1.9 1996/05/23 19:41:07 jaf */
- /* Commented out some unnecessary lines that were reading uninitialized */
- /* values. */
- /* Revision 1.8 1996/03/27 23:57:55 jaf */
- /* Added some comments about which indices of the local buffers INBUF, */
- /* LPBUF, etc., get read or modified by some of the subroutine calls. I */
- /* just did this while trying to figure out the discrepancy between the */
- /* embedded code compiled with all local variables implicitly saved, and */
- /* without. */
- /* I added some debugging write statements in hopes of finding a problem. */
- /* None of them ever printed anything while running with the long input */
- /* speech file dam9.spd provided in the distribution. */
- /* Revision 1.7 1996/03/27 18:06:20 jaf */
- /* Commented out access to MAXOSP, which is just a debugging variable */
- /* that was defined in the COMMON block CONTRL in contrl.fh. */
- /* Revision 1.6 1996/03/26 19:31:33 jaf */
- /* Commented out trace statements. */
- /* Revision 1.5 1996/03/21 15:19:35 jaf */
- /* Added comments for ENTRY PITDEC. */
- /* Revision 1.4 1996/03/19 20:54:27 jaf */
- /* Added a line to INITANALYS. See comments there. */
- /* Revision 1.3 1996/03/19 20:52:49 jaf */
- /* Rearranged the order of the local variables quite a bit, to separate */
- /* them into groups of "constants", "locals that don't need to be saved */
- /* from one call to the next", and "local that do need to be saved from */
- /* one call to the next". */
- /* Several locals in the last set should have been given initial values, */
- /* but weren't. I gave them all initial values of 0. */
- /* Added a separate ENTRY INITANALYS that initializes all local state */
- /* that should be, and also calls the corresponding entries of the */
- /* subroutines called by ANALYS that also have local state. */
- /* There used to be DATA statements in ANALYS. I got rid of most of */
- /* them, and added a local logical variable FIRST that calls the entry */
- /* INITANALYS on the first call to ANALYS. This is just so that one need */
- /* not remember to call INITANALYS first in order for the state to be */
- /* initialized. */
- /* Revision 1.2 1996/03/11 23:29:32 jaf */
- /* Added several comments with my own personal questions about the */
- /* Fortran 77 meaning of the parameters passed to the subroutine PREEMP. */
- /* Revision 1.1 1996/02/07 14:42:29 jaf */
- /* Initial revision */
- /* ****************************************************************** */
- /* SUBROUTINE ANALYS */
- /* Input: */
- /* SPEECH */
- /* Indices 1 through LFRAME read. */
- /* Output: */
- /* VOICE */
- /* Indices 1 through 2 written. */
- /* PITCH */
- /* Written in subroutine DYPTRK, and then perhaps read and written */
- /* some more. */
- /* RMS */
- /* Written. */
- /* RC */
- /* Indices 1 through ORDER written (ORDER defined in contrl.fh). */
- /* This subroutine maintains local state from one call to the next. If */
- /* you want to switch to using a new audio stream for this filter, or */
- /* reinitialize its state for any other reason, call the ENTRY */
- /* INITANALYS. */
- /* ENTRY PITDEC */
- /* Input: */
- /* PITCH - Encoded pitch index */
- /* Output: */
- /* PTAU - Decoded pitch period */
- /* This entry has no local state. It accesses a "constant" array */
- /* declared in ANALYS. */
- /* Subroutine */ int analys_(real *speech, integer *voice, integer
- *pitch, real *rms, real *rc, struct lpc10_encoder_state *st)
- {
- /* Initialized data */
- static integer tau[60] = { 20,21,22,23,24,25,26,27,28,29,30,31,32,33,34,
- 35,36,37,38,39,40,42,44,46,48,50,52,54,56,58,60,62,64,66,68,70,72,
- 74,76,78,80,84,88,92,96,100,104,108,112,116,120,124,128,132,136,
- 140,144,148,152,156 };
- static integer buflim[4] = { 181,720,25,720 };
- static real precoef = .9375f;
- /* System generated locals */
- integer i__1;
- /* Local variables */
- real amdf[60];
- integer half;
- real abuf[156];
- real *bias;
- extern /* Subroutine */ int tbdm_(real *, integer *, integer *, integer *,
- real *, integer *, integer *, integer *);
- integer *awin;
- integer midx, ewin[6] /* was [2][3] */;
- real ivrc[2], temp;
- real *zpre;
- integer *vwin;
- integer i__, j, lanal;
- extern /* Subroutine */ int rcchk_(integer *, real *, real *), mload_(
- integer *, integer *, integer *, real *, real *, real *);
- real *inbuf, *pebuf;
- real *lpbuf, *ivbuf;
- real *rcbuf;
- integer *osbuf;
- extern /* Subroutine */ int onset_(real *, integer *, integer *, integer *
- , integer *, integer *, integer *, struct lpc10_encoder_state *);
- integer *osptr;
- extern /* Subroutine */ placea_(integer *, integer *
- , integer *, integer *, integer *, integer *, integer *, integer *
- , integer *), dcbias_(integer *, real *, real *), placev_(integer
- *, integer *, integer *, integer *, integer *, integer *, integer
- *, integer *, integer *, integer *, integer *);
- integer ipitch;
- integer *obound;
- extern /* Subroutine */ int preemp_(real *, real *, integer *, real *,
- real *), voicin_(integer *, real *, real *, integer *, integer *,
- real *, real *, integer *, real *, integer *, integer *, integer *,
- struct lpc10_encoder_state *);
- integer *voibuf;
- integer mintau;
- real *rmsbuf;
- extern /* Subroutine */ int lpfilt_(real *, real *, integer *, integer *),
- ivfilt_(real *, real *, integer *, integer *, real *), energy_(
- integer *, real *, real *), invert_(integer *, real *, real *,
- real *);
- integer minptr, maxptr;
- extern /* Subroutine */ int dyptrk_(real *, integer *, integer *, integer
- *, integer *, integer *, struct lpc10_encoder_state *);
- real phi[100] /* was [10][10] */, psi[10];
- /* $Log: analys.c,v $
- /* Revision 1.1.1.1 2002/07/28 05:23:15 freeman_yong
- /* lpc10 codec
- /*
- * Revision 1.2 1996/08/20 20:16:01 jaf
- * Removed all static local variables that were SAVE'd in the Fortran
- * code, and put them in struct lpc10_encoder_state that is passed as an
- * argument.
- *
- * Removed init function, since all initialization is now done in
- * init_lpc10_encoder_state().
- *
- * Revision 1.1 1996/08/19 22:29:08 jaf
- * Initial revision
- * */
- /* Revision 1.3 1996/03/29 22:03:47 jaf */
- /* Removed definitions for any constants that were no longer used. */
- /* Revision 1.2 1996/03/26 19:34:33 jaf */
- /* Added comments indicating which constants are not needed in an */
- /* application that uses the LPC-10 coder. */
- /* Revision 1.1 1996/02/07 14:43:51 jaf */
- /* Initial revision */
- /* LPC Configuration parameters: */
- /* Frame size, Prediction order, Pitch period */
- /* Arguments to ANALYS */
- /* $Log: analys.c,v $
- /* Revision 1.1.1.1 2002/07/28 05:23:15 freeman_yong
- /* lpc10 codec
- /*
- * Revision 1.2 1996/08/20 20:16:01 jaf
- * Removed all static local variables that were SAVE'd in the Fortran
- * code, and put them in struct lpc10_encoder_state that is passed as an
- * argument.
- *
- * Removed init function, since all initialization is now done in
- * init_lpc10_encoder_state().
- *
- * Revision 1.1 1996/08/19 22:29:08 jaf
- * Initial revision
- * */
- /* Revision 1.3 1996/03/29 22:05:55 jaf */
- /* Commented out the common block variables that are not needed by the */
- /* embedded version. */
- /* Revision 1.2 1996/03/26 19:34:50 jaf */
- /* Added comments indicating which constants are not needed in an */
- /* application that uses the LPC-10 coder. */
- /* Revision 1.1 1996/02/07 14:44:09 jaf */
- /* Initial revision */
- /* LPC Processing control variables: */
- /* *** Read-only: initialized in setup */
- /* Files for Speech, Parameter, and Bitstream Input & Output, */
- /* and message and debug outputs. */
- /* Here are the only files which use these variables: */
- /* lpcsim.f setup.f trans.f error.f vqsetup.f */
- /* Many files which use fdebug are not listed, since it is only used in */
- /* those other files conditionally, to print trace statements. */
- /* integer fsi, fso, fpi, fpo, fbi, fbo, pbin, fmsg, fdebug */
- /* LPC order, Frame size, Quantization rate, Bits per frame, */
- /* Error correction */
- /* Subroutine SETUP is the only place where order is assigned a value, */
- /* and that value is 10. It could increase efficiency 1% or so to */
- /* declare order as a constant (i.e., a Fortran PARAMETER) instead of as
- */
- /* a variable in a COMMON block, since it is used in many places in the */
- /* core of the coding and decoding routines. Actually, I take that back.
- */
- /* At least when compiling with f2c, the upper bound of DO loops is */
- /* stored in a local variable before the DO loop begins, and then that is
- */
- /* compared against on each iteration. */
- /* Similarly for lframe, which is given a value of MAXFRM in SETUP. */
- /* Similarly for quant, which is given a value of 2400 in SETUP. quant */
- /* is used in only a few places, and never in the core coding and */
- /* decoding routines, so it could be eliminated entirely. */
- /* nbits is similar to quant, and is given a value of 54 in SETUP. */
- /* corrp is given a value of .TRUE. in SETUP, and is only used in the */
- /* subroutines ENCODE and DECODE. It doesn't affect the speed of the */
- /* coder significantly whether it is .TRUE. or .FALSE., or whether it is
- */
- /* a constant or a variable, since it is only examined once per frame. */
- /* Leaving it as a variable that is set to .TRUE. seems like a good */
- /* idea, since it does enable some error-correction capability for */
- /* unvoiced frames, with no change in the coding rate, and no noticeable
- */
- /* quality difference in the decoded speech. */
- /* integer quant, nbits */
- /* *** Read/write: variables for debugging, not needed for LPC algorithm
- */
- /* Current frame, Unstable frames, Output clip count, Max onset buffer,
- */
- /* Debug listing detail level, Line count on listing page */
- /* nframe is not needed for an embedded LPC10 at all. */
- /* nunsfm is initialized to 0 in SETUP, and incremented in subroutine */
- /* ERROR, which is only called from RCCHK. When LPC10 is embedded into */
- /* an application, I would recommend removing the call to ERROR in RCCHK,
- */
- /* and remove ERROR and nunsfm completely. */
- /* iclip is initialized to 0 in SETUP, and incremented in entry SWRITE in
- */
- /* sread.f. When LPC10 is embedded into an application, one might want */
- /* to cause it to be incremented in a routine that takes the output of */
- /* SYNTHS and sends it to an audio device. It could be optionally */
- /* displayed, for those that might want to know what it is. */
- /* maxosp is never initialized to 0 in SETUP, although it probably should
- */
- /* be, and it is updated in subroutine ANALYS. I doubt that its value */
- /* would be of much interest to an application in which LPC10 is */
- /* embedded. */
- /* listl and lincnt are not needed for an embedded LPC10 at all. */
- /* integer nframe, nunsfm, iclip, maxosp, listl, lincnt */
- /* common /contrl/ fsi, fso, fpi, fpo, fbi, fbo, pbin, fmsg, fdebug */
- /* common /contrl/ quant, nbits */
- /* common /contrl/ nframe, nunsfm, iclip, maxosp, listl, lincnt */
- /* Arguments to entry PITDEC (below) */
- /* Parameters/constants */
- /* Constants */
- /* NF = Number of frames */
- /* AF = Frame in which analysis is done */
- /* OSLEN = Length of the onset buffer */
- /* LTAU = Number of pitch lags */
- /* SBUFL, SBUFH = Start and end index of speech buffers */
- /* LBUFL, LBUFH = Start and end index of LPF speech buffer */
- /* MINWIN, MAXWIN = Min and Max length of voicing (and analysis) windows
- */
- /* PWLEN, PWINH, PWINL = Length, upper and lower limits of pitch window
- */
- /* DVWINL, DVWINH = Default lower and upper limits of voicing window */
- /* The tables TAU and BUFLIM, and the variable PRECOEF, are not */
- /* Fortran PARAMETER's, but they are initialized with DATA */
- /* statements, and never modified. Thus, they need not have SAVE */
- /* statements for them to keep their values from one invocation to
- */
- /* the next. */
- /* Local variables that need not be saved */
- /* Local state */
- /* Data Buffers */
- /* INBUF Raw speech (with DC bias removed each frame) */
- /* PEBUF Preemphasized speech */
- /* LPBUF Low pass speech buffer */
- /* IVBUF Inverse filtered speech */
- /* OSBUF Indexes of onsets in speech buffers */
- /* VWIN Voicing window indices */
- /* AWIN Analysis window indices */
- /* EWIN Energy window indices */
- /* VOIBUF Voicing decisions on windows in VWIN */
- /* RMSBUF RMS energy */
- /* RCBUF Reflection Coefficients */
- /* Pitch is handled separately from the above parameters. */
- /* The following variables deal with pitch: */
- /* MIDX Encoded initial pitch estimate for analysis frame */
- /* IPITCH Initial pitch computed for frame AF (decoded from MIDX) */
- /* PITCH The encoded pitch value (index into TAU) for the present */
- /* frame (delayed and smoothed by Dyptrack) */
- /* Parameter adjustments */
- if (speech) {
- --speech;
- }
- if (voice) {
- --voice;
- }
- if (rc) {
- --rc;
- }
- /* Function Body */
- /* Calculations are done on future frame due to requirements */
- /* of the pitch tracker. Delay RMS and RC's 2 frames to give */
- /* current frame parameters on return. */
- /* Update all buffers */
- inbuf = &(st->inbuf[0]);
- pebuf = &(st->pebuf[0]);
- lpbuf = &(st->lpbuf[0]);
- ivbuf = &(st->ivbuf[0]);
- bias = &(st->bias);
- osbuf = &(st->osbuf[0]);
- osptr = &(st->osptr);
- obound = &(st->obound[0]);
- vwin = &(st->vwin[0]);
- awin = &(st->awin[0]);
- voibuf = &(st->voibuf[0]);
- rmsbuf = &(st->rmsbuf[0]);
- rcbuf = &(st->rcbuf[0]);
- zpre = &(st->zpre);
- i__1 = 720 - contrl_1.lframe;
- for (i__ = 181; i__ <= i__1; ++i__) {
- inbuf[i__ - 181] = inbuf[contrl_1.lframe + i__ - 181];
- pebuf[i__ - 181] = pebuf[contrl_1.lframe + i__ - 181];
- }
- i__1 = 540 - contrl_1.lframe;
- for (i__ = 229; i__ <= i__1; ++i__) {
- ivbuf[i__ - 229] = ivbuf[contrl_1.lframe + i__ - 229];
- }
- i__1 = 720 - contrl_1.lframe;
- for (i__ = 25; i__ <= i__1; ++i__) {
- lpbuf[i__ - 25] = lpbuf[contrl_1.lframe + i__ - 25];
- }
- j = 1;
- i__1 = (*osptr) - 1;
- for (i__ = 1; i__ <= i__1; ++i__) {
- if (osbuf[i__ - 1] > contrl_1.lframe) {
- osbuf[j - 1] = osbuf[i__ - 1] - contrl_1.lframe;
- ++j;
- }
- }
- *osptr = j;
- voibuf[0] = voibuf[2];
- voibuf[1] = voibuf[3];
- for (i__ = 1; i__ <= 2; ++i__) {
- vwin[(i__ << 1) - 2] = vwin[(i__ + 1 << 1) - 2] - contrl_1.lframe;
- vwin[(i__ << 1) - 1] = vwin[(i__ + 1 << 1) - 1] - contrl_1.lframe;
- awin[(i__ << 1) - 2] = awin[(i__ + 1 << 1) - 2] - contrl_1.lframe;
- awin[(i__ << 1) - 1] = awin[(i__ + 1 << 1) - 1] - contrl_1.lframe;
- /* EWIN(*,J) is unused for J .NE. AF, so the following shift is
- */
- /* unnecessary. It also causes error messages when the C versio
- n */
- /* of the code created from this by f2c is run with Purify. It
- */
- /* correctly complains that uninitialized memory is being read.
- */
- /* EWIN(1,I) = EWIN(1,I+1) - LFRAME */
- /* EWIN(2,I) = EWIN(2,I+1) - LFRAME */
- obound[i__ - 1] = obound[i__];
- voibuf[i__ * 2] = voibuf[(i__ + 1) * 2];
- voibuf[(i__ << 1) + 1] = voibuf[(i__ + 1 << 1) + 1];
- rmsbuf[i__ - 1] = rmsbuf[i__];
- i__1 = contrl_1.order;
- for (j = 1; j <= i__1; ++j) {
- rcbuf[j + i__ * 10 - 11] = rcbuf[j + (i__ + 1) * 10 - 11];
- }
- }
- /* Copy input speech, scale to sign+12 bit integers */
- /* Remove long term DC bias. */
- /* If the average value in the frame was over 1/4096 (after current
- */
- /* BIAS correction), then subtract that much more from samples in */
- /* next frame. If the average value in the frame was under */
- /* -1/4096, add 1/4096 more to samples in next frame. In all other
- */
- /* cases, keep BIAS the same. */
- temp = 0.f;
- i__1 = contrl_1.lframe;
- for (i__ = 1; i__ <= i__1; ++i__) {
- inbuf[720 - contrl_1.lframe + i__ - 181] = speech[i__] * 4096.f -
- (*bias);
- temp += inbuf[720 - contrl_1.lframe + i__ - 181];
- }
- if (temp > (real) contrl_1.lframe) {
- *bias += 1;
- }
- if (temp < (real) (-contrl_1.lframe)) {
- *bias += -1;
- }
- /* Place Voicing Window */
- i__ = 721 - contrl_1.lframe;
- preemp_(&inbuf[i__ - 181], &pebuf[i__ - 181], &contrl_1.lframe, &precoef,
- zpre);
- onset_(pebuf, osbuf, osptr, &c__10, &c__181, &c__720, &contrl_1.lframe, st);
- /* MAXOSP is just a debugging variable. */
- /* MAXOSP = MAX( MAXOSP, OSPTR ) */
- placev_(osbuf, osptr, &c__10, &obound[2], vwin, &c__3, &contrl_1.lframe,
- &c__90, &c__156, &c__307, &c__462);
- /* The Pitch Extraction algorithm estimates the pitch for a frame
- */
- /* of speech by locating the minimum of the average magnitude difference
- */
- /* function (AMDF). The AMDF operates on low-pass, inverse filtered */
- /* speech. (The low-pass filter is an 800 Hz, 19 tap, equiripple, FIR
- */
- /* filter and the inverse filter is a 2nd-order LPC filter.) The pitch
- */
- /* estimate is later refined by dynamic programming (DYPTRK). However,
- */
- /* since some of DYPTRK's parameters are a function of the voicing */
- /* decisions, a voicing decision must precede the final pitch estimation.
- */
- /* See subroutines LPFILT, IVFILT, and TBDM. */
- /* LPFILT reads indices LBUFH-LFRAME-29 = 511 through LBUFH = 720 */
- /* of INBUF, and writes indices LBUFH+1-LFRAME = 541 through LBUFH
- */
- /* = 720 of LPBUF. */
- lpfilt_(&inbuf[228], &lpbuf[384], &c__312, &contrl_1.lframe);
- /* IVFILT reads indices (PWINH-LFRAME-7) = 353 through PWINH = 540
- */
- /* of LPBUF, and writes indices (PWINH-LFRAME+1) = 361 through */
- /* PWINH = 540 of IVBUF. */
- ivfilt_(&lpbuf[204], ivbuf, &c__312, &contrl_1.lframe, ivrc);
- /* TBDM reads indices PWINL = 229 through */
- /* (PWINL-1)+MAXWIN+(TAU(LTAU)-TAU(1))/2 = 452 of IVBUF, and writes
- */
- /* indices 1 through LTAU = 60 of AMDF. */
- tbdm_(ivbuf, &c__156, tau, &c__60, amdf, &minptr, &maxptr, &mintau);
- /* Voicing decisions are made for each half frame of input speech.
- */
- /* An initial voicing classification is made for each half of the */
- /* analysis frame, and the voicing decisions for the present frame */
- /* are finalized. See subroutine VOICIN. */
- /* The voicing detector (VOICIN) classifies the input signal as */
- /* unvoiced (including silence) or voiced using the AMDF windowed */
- /* maximum-to-minimum ratio, the zero crossing rate, energy measures, */
- /* reflection coefficients, and prediction gains. */
- /* The pitch and voicing rules apply smoothing and isolated */
- /* corrections to the pitch and voicing estimates and, in the process,
- */
- /* introduce two frames of delay into the corrected pitch estimates and
- */
- /* voicing decisions. */
- for (half = 1; half <= 2; ++half) {
- voicin_(&vwin[4], inbuf, lpbuf, buflim, &half, &amdf[minptr - 1], &
- amdf[maxptr - 1], &mintau, ivrc, obound, voibuf, &c__3, st);
- }
- /* Find the minimum cost pitch decision over several frames */
- /* given the current voicing decision and the AMDF array */
- dyptrk_(amdf, &c__60, &minptr, &voibuf[7], pitch, &midx, st);
- ipitch = tau[midx - 1];
- /* Place spectrum analysis and energy windows */
- placea_(&ipitch, voibuf, &obound[2], &c__3, vwin, awin, ewin, &
- contrl_1.lframe, &c__156);
- /* Remove short term DC bias over the analysis window, Put result in ABUF
- */
- lanal = awin[5] + 1 - awin[4];
- dcbias_(&lanal, &pebuf[awin[4] - 181], abuf);
- /* ABUF(1:LANAL) is now defined. It is equal to */
- /* PEBUF(AWIN(1,AF):AWIN(2,AF)) corrected for short term DC bias. */
- /* Compute RMS over integer number of pitch periods within the */
- /* analysis window. */
- /* Note that in a hardware implementation this computation may be */
- /* simplified by using diagonal elements of PHI computed by MLOAD. */
- i__1 = ewin[5] - ewin[4] + 1;
- energy_(&i__1, &abuf[ewin[4] - awin[4]], &rmsbuf[2]);
- /* Matrix load and invert, check RC's for stability */
- mload_(&contrl_1.order, &c__1, &lanal, abuf, phi, psi);
- invert_(&contrl_1.order, phi, psi, &rcbuf[20]);
- rcchk_(&contrl_1.order, &rcbuf[10], &rcbuf[20]);
- /* Set return parameters */
- voice[1] = voibuf[2];
- voice[2] = voibuf[3];
- *rms = rmsbuf[0];
- i__1 = contrl_1.order;
- for (i__ = 1; i__ <= i__1; ++i__) {
- rc[i__] = rcbuf[i__ - 1];
- }
- return 0;
- } /* analys_ */