ref: 45b161d73ec087a8e003747b1aed07cd33589bca
dir: /lpc10/encode.c/
/*
* Revision 1.1 1996/08/19 22:32:21 jaf
* Initial revision
*
*/
/* -- translated by f2c (version 19951025).
You must link the resulting object file with the libraries:
-lf2c -lm (in that order)
*/
#include "f2c.h"
extern int encode_(integer *voice, integer *pitch, real *rms, real *rc, integer *ipitch, integer *irms, integer *irc);
/* Common Block Declarations */
extern struct {
integer order, lframe;
logical corrp;
} contrl_;
#define contrl_1 contrl_
/* Table of constant values */
static integer c__2 = 2;
/* ***************************************************************** */
/* ENCODE Version 54 */
/*
* Revision 1.1 1996/08/19 22:32:21 jaf
* Initial revision
* */
/* Revision 1.5 1996/03/26 19:35:50 jaf */
/* Commented out trace statements. */
/* Revision 1.4 1996/03/21 00:26:29 jaf */
/* Added the comment that this subroutine has no local state. */
/* In the last check-in, I forgot to mention that I had added comments */
/* explaining which indices of array arguments are read or written. */
/* Revision 1.3 1996/03/21 00:22:39 jaf */
/* Added comments explaining that all local arrays are effectively */
/* constants. */
/* Revision 1.2 1996/03/13 18:48:33 jaf */
/* Comments added explaining that none of the local variables of this */
/* subroutine need to be saved from one invocation to the next. */
/* Revision 1.1 1996/02/07 14:45:29 jaf */
/* Initial revision */
/* ***************************************************************** */
/* Quantize LPC parameters for transmission */
/* INPUTS: */
/* VOICE - Half frame voicing decisions */
/* Indices 1 through 2 read. */
/* PITCH - Pitch */
/* RMS - Energy */
/* RC - Reflection coefficients */
/* Indices 1 through ORDER read. */
/* CORRP - Error Correction: TRUE = yes, FALSE = none */
/* (this is defined in file control.fh) */
/* OUTPUTS: */
/* IPITCH - Coded pitch and voicing */
/* IRMS - Quantized energy */
/* IRC - Quantized reflection coefficients */
/* Indices 1 through MAX(ORDER,2) written. */
/* If CORRP is .TRUE., then indices 1 through 10 written */
/* for unvoiced frames. */
/* This subroutine has no local state. */
/* Subroutine */ int encode_(integer *voice, integer *pitch, real *rms, real *
rc, integer *ipitch, integer *irms, integer *irc)
{
/* Initialized data */
static integer enctab[16] = { 0,7,11,12,13,10,6,1,14,9,5,2,3,4,8,15 };
static integer entau[60] = { 19,11,27,25,29,21,23,22,30,14,15,7,39,38,46,
42,43,41,45,37,53,49,51,50,54,52,60,56,58,26,90,88,92,84,86,82,83,
81,85,69,77,73,75,74,78,70,71,67,99,97,113,112,114,98,106,104,108,
100,101,76 };
static integer enadd[8] = { 1920,-768,2432,1280,3584,1536,2816,-1152 };
static real enscl[8] = { .0204f,.0167f,.0145f,.0147f,.0143f,.0135f,.0125f,
.0112f };
static integer enbits[8] = { 6,5,4,4,4,4,3,3 };
static integer entab6[64] = { 0,0,0,0,0,0,1,1,1,1,1,1,1,2,2,2,2,2,2,2,3,3,
3,3,3,3,3,4,4,4,4,4,4,4,5,5,5,5,5,6,6,6,6,6,7,7,7,7,7,8,8,8,8,9,9,
9,10,10,11,11,12,13,14,15 };
static integer rmst[64] = { 1024,936,856,784,718,656,600,550,502,460,420,
384,352,328,294,270,246,226,206,188,172,158,144,132,120,110,102,
92,84,78,70,64,60,54,50,46,42,38,34,32,30,26,24,22,20,18,17,16,15,
14,13,12,11,10,9,8,7,6,5,4,3,2,1,0 };
/* System generated locals */
integer i__1, i__2;
/* Builtin functions */
integer pow_ii(integer *, integer *);
/* Local variables */
integer idel, nbit, i__, j, i2, i3, mrk;
/* LPC Configuration parameters: */
/* Frame size, Prediction order, Pitch period */
/* Arguments */
/* 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 */
/* Parameters/constants */
/* These arrays are not Fortran PARAMETER's, but they are defined */
/* by DATA statements below, and their contents are never altered.
*/
/* Local variables that need not be saved */
/* Parameter adjustments */
--irc;
--rc;
--voice;
/* Function Body */
/* Scale RMS and RC's to integers */
*irms = *rms;
i__1 = contrl_1.order;
for (i__ = 1; i__ <= i__1; ++i__) {
irc[i__] = rc[i__] * 32768.f;
}
/* IF(LISTL.GE.3)WRITE(FDEBUG,800)VOICE,PITCH,IRMS,(IRC(I),I=1,ORDER) */
/* 800 FORMAT(1X,/,' <<ENCODE IN>>',T32,2I3,I6,I5,T50,10I8) */
/* Encode pitch and voicing */
if (voice[1] != 0 && voice[2] != 0) {
*ipitch = entau[*pitch - 1];
} else {
if (contrl_1.corrp) {
*ipitch = 0;
if (voice[1] != voice[2]) {
*ipitch = 127;
}
} else {
*ipitch = (voice[1] << 1) + voice[2];
}
}
/* Encode RMS by binary table search */
j = 32;
idel = 16;
*irms = min(*irms,1023);
while(idel > 0) {
if (*irms > rmst[j - 1]) {
j -= idel;
}
if (*irms < rmst[j - 1]) {
j += idel;
}
idel /= 2;
}
if (*irms > rmst[j - 1]) {
--j;
}
*irms = 31 - j / 2;
/* Encode RC(1) and (2) as log-area-ratios */
for (i__ = 1; i__ <= 2; ++i__) {
i2 = irc[i__];
mrk = 0;
if (i2 < 0) {
i2 = -i2;
mrk = 1;
}
i2 /= 512;
i2 = min(i2,63);
i2 = entab6[i2];
if (mrk != 0) {
i2 = -i2;
}
irc[i__] = i2;
}
/* Encode RC(3) - (10) linearly, remove bias then scale */
i__1 = contrl_1.order;
for (i__ = 3; i__ <= i__1; ++i__) {
i2 = irc[i__] / 2;
i2 = (i2 + enadd[contrl_1.order + 1 - i__ - 1]) * enscl[
contrl_1.order + 1 - i__ - 1];
/* Computing MIN */
i__2 = max(i2,-127);
i2 = min(i__2,127);
nbit = enbits[contrl_1.order + 1 - i__ - 1];
i3 = 0;
if (i2 < 0) {
i3 = -1;
}
i2 /= pow_ii(&c__2, &nbit);
if (i3 == -1) {
--i2;
}
irc[i__] = i2;
}
/* Protect the most significant bits of the most */
/* important parameters during non-voiced frames. */
/* RC(1) - RC(4) are protected using 20 parity bits */
/* replacing RC(5) - RC(10). */
if (contrl_1.corrp) {
if (*ipitch == 0 || *ipitch == 127) {
irc[5] = enctab[(irc[1] & 30) / 2];
irc[6] = enctab[(irc[2] & 30) / 2];
irc[7] = enctab[(irc[3] & 30) / 2];
irc[8] = enctab[(*irms & 30) / 2];
irc[9] = enctab[(irc[4] & 30) / 2] / 2;
irc[10] = enctab[(irc[4] & 30) / 2] & 1;
}
}
/* IF(LISTL.GE.3)WRITE(FDEBUG,801)VOICE,IPITCH,IRMS,(IRC(J),J=1,ORDER) */
/* 801 FORMAT(1X,'<<ENCODE OUT>>',T32,2I3,I6,I5,T50,10I8) */
return 0;
} /* encode_ */