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/*  * Revision 1.2  1996/08/20  20:30:11  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(). * * Changed name of function from lpcenc_ to lpc10_encode, simply to make * all lpc10 functions have more consistent naming with each other. * * Revision 1.1  1996/08/19  22:31:48  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 lpcdec_(integer *bits, real *speech);extern int initlpcdec_(void); /* Common Block Declarations */ extern struct {    integer order, lframe;    logical corrp;} contrl_; #define contrl_1 contrl_ /* Table of constant values */ static integer c__10 = 10; /* ***************************************************************** */ /* * Revision 1.2  1996/08/20  20:30:11  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(). * * Changed name of function from lpcenc_ to lpc10_encode, simply to make * all lpc10 functions have more consistent naming with each other. * * Revision 1.1  1996/08/19  22:31:48  jaf * Initial revision * *//* Revision 1.1  1996/03/28  00:03:00  jaf *//* Initial revision */  /* ***************************************************************** */ /* Decode 54 bits to one frame of 180 speech samples. */ /* Input: *//*  BITS   - 54 encoded bits, stored 1 per array element. *//*           Indices 1 through 53 read (SYNC bit ignored). *//* Output: *//*  SPEECH - Speech encoded as real values in the range [-1,+1]. *//*           Indices 1 through 180 written. */ /* 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 *//* INITLPCDEC. */ /* Subroutine */ int lpc10_decode(integer *bits, real *speech,				  struct lpc10_decoder_state *st){    integer irms, voice[2], pitch, ipitv;    extern /* Subroutine */ int decode_(integer *, integer *, integer *, 	    integer *, integer *, real *, real *, struct lpc10_decoder_state *);    real rc[10];    extern /* Subroutine */ int chanrd_(integer *, integer *, integer *, 	    integer *, integer *), synths_(integer *, 	    integer *, real *, real *, real *, integer *,					   struct lpc10_decoder_state *);    integer irc[10], len;    real rms;  /*   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 *//*       Local variables that need not be saved *//*       Uncoded speech parameters *//*       Coded speech parameters *//*       Others *//*       Local state *//*       None */    /* Parameter adjustments */    if (bits) {	--bits;	}    if (speech) {	--speech;	}     /* Function Body */     chanrd_(&c__10, &ipitv, &irms, irc, &bits[1]);    decode_(&ipitv, &irms, irc, voice, &pitch, &rms, rc, st);    synths_(voice, &pitch, &rms, rc, &speech[1], &len, st);    return 0;} /* lpcdec_ */

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