lpc10/lpcenc.c

   1 /*
   2
   3  * Revision 1.2  1996/08/20  20:31:21  jaf
   4  * Removed all static local variables that were SAVE'd in the Fortran
   5  * code, and put them in struct lpc10_encoder_state that is passed as an
   6  * argument.
   7  *
   8  * Removed init function, since all initialization is now done in
   9  * init_lpc10_encoder_state().
  10  *
  11  * Changed name of function from lpcenc_ to lpc10_encode, simply to make
  12  * all lpc10 functions have more consistent naming with each other.
  13  *
  14  * Revision 1.1  1996/08/19  22:31:44  jaf
  15  * Initial revision
  16  *
  17
  18 */
  19
  20 /*  -- translated by f2c (version 19951025).
  21    You must link the resulting object file with the libraries:
  22         -lf2c -lm   (in that order)
  23 */
  24
  25 #include "f2c.h"
  26
  27 extern int lpcenc_(real *speech, integer *bits);
  28 extern int initlpcenc_(void);
  29
  30 /* Table of constant values */
  31
  32 static integer c__180 = 180;
  33 static integer c__10 = 10;
  34
  35 /* ***************************************************************** */
  36
  37 /*
  38  * Revision 1.2  1996/08/20  20:31:21  jaf
  39  * Removed all static local variables that were SAVE'd in the Fortran
  40  * code, and put them in struct lpc10_encoder_state that is passed as an
  41  * argument.
  42  *
  43  * Removed init function, since all initialization is now done in
  44  * init_lpc10_encoder_state().
  45  *
  46  * Changed name of function from lpcenc_ to lpc10_encode, simply to make
  47  * all lpc10 functions have more consistent naming with each other.
  48  *
  49  * Revision 1.1  1996/08/19  22:31:44  jaf
  50  * Initial revision
  51  * */
  52 /* Revision 1.2  1996/03/28  00:01:22  jaf */
  53 /* Commented out some trace statements. */
  54
  55 /* Revision 1.1  1996/03/28  00:00:27  jaf */
  56 /* Initial revision */
  57
  58
  59 /* ***************************************************************** */
  60
  61 /* Encode one frame of 180 speech samples to 54 bits. */
  62
  63 /* Input: */
  64 /*  SPEECH - Speech encoded as real values in the range [-1,+1]. */
  65 /*           Indices 1 through 180 read, and modified (by PREPRO). */
  66 /* Output: */
  67 /*  BITS   - 54 encoded bits, stored 1 per array element. */
  68 /*           Indices 1 through 54 written. */
  69
  70 /* This subroutine maintains local state from one call to the next.  If */
  71 /* you want to switch to using a new audio stream for this filter, or */
  72 /* reinitialize its state for any other reason, call the ENTRY */
  73 /* INITLPCENC. */
  74
  75 /* Subroutine */ int lpc10_encode(real *speech, integer *bits,
  76                                   struct lpc10_encoder_state *st)
  77 {
  78     integer irms, voice[2], pitch, ipitv;
  79     real rc[10];
  80     extern /* Subroutine */ int encode_(integer *, integer *, real *, real *,
  81             integer *, integer *, integer *), chanwr_(integer *, integer *,
  82             integer *, integer *, integer *, struct lpc10_encoder_state *),
  83             analys_(real *, integer *,
  84             integer *, real *, real *, struct lpc10_encoder_state *),
  85             prepro_(real *, integer *, struct lpc10_encoder_state *);
  86     integer irc[10];
  87     real rms;
  88
  89 /*       Arguments */
  90
  91 /*   LPC Configuration parameters: */
  92 /* Frame size, Prediction order, Pitch period */
  93 /*       Local variables that need not be saved */
  94 /*       Uncoded speech parameters */
  95 /*       Coded speech parameters */
  96 /*       Local state */
  97 /*       None */
  98     /* Parameter adjustments */
  99     if (speech) {
 100         --speech;
 101         }
 102     if (bits) {
 103         --bits;
 104         }
 105
 106     /* Function Body */
 107     prepro_(&speech[1], &c__180, st);
 108     analys_(&speech[1], voice, &pitch, &rms, rc, st);
 109     encode_(voice, &pitch, &rms, rc, &ipitv, &irms, irc);
 110     chanwr_(&c__10, &ipitv, &irms, irc, &bits[1], st);
 111     return 0;
 112 } /* lpcenc_ */