short_term.c File Reference

#include <stdio.h>
#include <assert.h>
#include "private.h"
#include "gsm.h"
#include "proto.h"

Include dependency graph for short_term.c:

Go to the source code of this file.

Macros
#define	FILTER   Short_term_analysis_filtering
#define	FILTER   Short_term_synthesis_filtering
#define	STEP(B_TIMES_TWO, MIC, INVA)

Functions
static void LARp_to_rp	P1 ((LARp), register word *LARp)
static void Decoding_of_the_coded_Log_Area_Ratios	P2 ((LARc, LARpp), word *LARc, word *LARpp)
static void Coefficients_40_159	P2 ((LARpp_j, LARp), register word *LARpp_j, register word *LARp)
static void Coefficients_0_12	P3 ((LARpp_j_1, LARpp_j, LARp), register word *LARpp_j_1, register word *LARpp_j, register word *LARp)
void Gsm_Short_Term_Analysis_Filter	P3 ((S, LARc, s), struct gsm_state *S, word *LARc, word *s)
static void Short_term_analysis_filtering	P4 ((u0, rp0, k_n, s), register word *u0, register word *rp0, register int k_n, register word *s)
void Gsm_Short_Term_Synthesis_Filter	P4 ((S, LARcr, wt, s), struct gsm_state *S, word *LARcr, word *wt, word *s)
static void Short_term_synthesis_filtering	P5 ((S, rrp, k, wt, sr), struct gsm_state *S, register word *rrp, register int k, register word *wt, register word *sr)

Macro Definition Documentation

FILTER [1/2]

#define FILTER   Short_term_analysis_filtering

Referenced by P3(), and P4().

FILTER [2/2]

#define FILTER   Short_term_synthesis_filtering

STEP

#define STEP	(		B_TIMES_TWO,
			MIC,
			INVA
	)

Value:

temp1    = GSM_ADD( *LARc++, MIC ) << 10; \
      temp1    = GSM_SUB( temp1, B_TIMES_TWO ); \
      temp1    = (word)GSM_MULT_R( INVA, temp1 );     \
      *LARpp++ = GSM_ADD( temp1, temp1 );

Referenced by P2().

Function Documentation

P1()

static void LARp_to_rp P1 ( (LARp)  , register word *  LARp  )

static

Definition at line 145 of file short_term.c.

References GSM_ADD(), MAX_WORD, and MIN_WORD.

{
   register int      i;
   register word     temp;

   for (i = 1; i <= 8; i++, LARp++) {

      /* temp = GSM_ABS( *LARp );
            *
       * if (temp < 11059) temp <<= 1;
       * else if (temp < 20070) temp += 11059;
       * else temp = GSM_ADD( temp >> 2, 26112 );
       *
       * *LARp = *LARp < 0 ? -temp : temp;
       */

      if (*LARp < 0) {
         temp = *LARp == MIN_WORD ? MAX_WORD : -(*LARp);
         *LARp = - ((temp < 11059) ? temp << 1
            : ((temp < 20070) ? temp + 11059
            :  GSM_ADD( temp >> 2, 26112 )));
      } else {
         temp  = *LARp;
         *LARp =    (temp < 11059) ? temp << 1
            : ((temp < 20070) ? temp + 11059
            :  GSM_ADD( temp >> 2, 26112 ));
      }
   }
}

P2() [1/2]

static void Decoding_of_the_coded_Log_Area_Ratios P2 ( (LARc, LARpp)  , word *  LARc, word *  LARpp  )

static

Definition at line 28 of file short_term.c.

References STEP.

{
   register word  temp1 /* , temp2 */;

   /*  This procedure requires for efficient implementation
    *  two tables.
    *
    *  INVA[1..8] = integer( (32768 * 8) / real_A[1..8])
    *  MIC[1..8]  = minimum value of the LARc[1..8]
    */

   /*  Compute the LARpp[1..8]
    */

   /*    for (i = 1; i <= 8; i++, B++, MIC++, INVA++, LARc++, LARpp++) {
    *
    *    temp1  = GSM_ADD( *LARc, *MIC ) << 10;
    *    temp2  = *B << 1;
    *    temp1  = GSM_SUB( temp1, temp2 );
    *
    *    assert(*INVA != MIN_WORD);
    *
    *    temp1  = GSM_MULT_R( *INVA, temp1 );
    *    *LARpp = GSM_ADD( temp1, temp1 );
    * }
    */

#undef   STEP
#define  STEP( B_TIMES_TWO, MIC, INVA )   \
      temp1    = GSM_ADD( *LARc++, MIC ) << 10; \
      temp1    = GSM_SUB( temp1, B_TIMES_TWO ); \
      temp1    = (word)GSM_MULT_R( INVA, temp1 );     \
      *LARpp++ = GSM_ADD( temp1, temp1 );

   STEP(      0,  -32,  13107 );
   STEP(      0,  -32,  13107 );
   STEP(   4096,  -16,  13107 );
   STEP(  -5120,  -16,  13107 );

   STEP(    188,   -8,  19223 );
   STEP(  -3584,   -8,  17476 );
   STEP(   -682,   -4,  31454 );
   STEP(  -2288,   -4,  29708 );

   /* NOTE: the addition of *MIC is used to restore
    *     the sign of *LARc.
    */
}

P2() [2/2]

static void Coefficients_40_159 P2 ( (LARpp_j, LARp)  , register word *  LARpp_j, register word *  LARp  )

static

Definition at line 133 of file short_term.c.

{
   register int i;

   for (i = 1; i <= 8; i++, LARp++, LARpp_j++)
      *LARp = *LARpp_j;
}

P3() [1/2]

static void Coefficients_27_39 P3 ( (LARpp_j_1, LARpp_j, LARp)  , register word *  LARpp_j_1, register word *  LARpp_j, register word *  LARp  )

static

Definition at line 95 of file short_term.c.

References GSM_ADD(), and SASR.

{
   register int   i;

   for (i = 1; i <= 8; i++, LARp++, LARpp_j_1++, LARpp_j++) {
      *LARp = GSM_ADD( SASR( *LARpp_j_1, 2 ), SASR( *LARpp_j, 2 ));
      *LARp = GSM_ADD( *LARp,  SASR( *LARpp_j_1, 1));
   }
}

P3() [2/2]

void Gsm_Short_Term_Analysis_Filter P3	(	(S, LARc, s)	,
		struct gsm_state *	S,
		word *	LARc,
		word *	s
	)

Definition at line 364 of file short_term.c.

References FILTER, gsm_state::j, gsm_state::LARpp, and gsm_state::u.

{
   word     * LARpp_j   = S->LARpp[ S->j      ];
   word     * LARpp_j_1 = S->LARpp[ S->j ^= 1 ];

   word     LARp[8];

#undef   FILTER
#if   defined(FAST) && defined(USE_FLOAT_MUL)
#  define   FILTER   (* (S->fast       \
            ? Fast_Short_term_analysis_filtering   \
               : Short_term_analysis_filtering  ))

#else
#  define   FILTER   Short_term_analysis_filtering
#endif

   Decoding_of_the_coded_Log_Area_Ratios( LARc, LARpp_j );

   Coefficients_0_12(  LARpp_j_1, LARpp_j, LARp );
   LARp_to_rp( LARp );
   FILTER( S->u, LARp, 13, s);

   Coefficients_13_26( LARpp_j_1, LARpp_j, LARp);
   LARp_to_rp( LARp );
   FILTER( S->u, LARp, 14, s + 13);

   Coefficients_27_39( LARpp_j_1, LARpp_j, LARp);
   LARp_to_rp( LARp );
   FILTER( S->u, LARp, 13, s + 27);

   Coefficients_40_159( LARpp_j, LARp);
   LARp_to_rp( LARp );
   FILTER( S->u, LARp, 120, s + 40);

}

P4() [1/2]

static void Short_term_analysis_filtering P4 ( (u0, rp0, k_n, s)  , register word *  u0, register word *  rp0, register int  k_n, register word *  s  )

static

Definition at line 190 of file short_term.c.

References di, MAX_WORD, and MIN_WORD.

{
   register word     * u_top = u0 + 8;
   register word     * s_top = s + k_n;

   while (s < s_top) {
      register word     *u, *rp ;
      register longword    di, u_out;
      di = u_out = *s;
      for (rp=rp0, u=u0; u<u_top;) {
         register longword ui, rpi;
         ui    = *u;
         *u++  = (word)u_out;
         rpi   = *rp++;
         u_out = ui + (((rpi*di)+0x4000)>>15);
         di    = di + (((rpi*ui)+0x4000)>>15);
         /* make the common case fastest: */
         if ((u_out == (word)u_out) && (di == (word)di)) continue;
         /* otherwise do slower fixup (saturation) */
         if (u_out>MAX_WORD) u_out=MAX_WORD;
         else if (u_out<MIN_WORD) u_out=MIN_WORD;
         if (di>MAX_WORD) di=MAX_WORD;
         else if (di<MIN_WORD) di=MIN_WORD;
      }
      *s++ = (word)di;
   }
}

P4() [2/2]

void Gsm_Short_Term_Synthesis_Filter P4	(	(S, LARcr, wt, s)	,
		struct gsm_state *	S,
		word *	LARcr,
		word *	wt,
		word *	s
	)

Definition at line 407 of file short_term.c.

References FILTER, gsm_state::j, and gsm_state::LARpp.

{
   word     * LARpp_j   = S->LARpp[ S->j     ];
   word     * LARpp_j_1 = S->LARpp[ S->j ^=1 ];

   word     LARp[8];

#undef   FILTER
#if   defined(FAST) && defined(USE_FLOAT_MUL)

#  define   FILTER   (* (S->fast       \
            ? Fast_Short_term_synthesis_filtering  \
               : Short_term_synthesis_filtering ))
#else
#  define   FILTER   Short_term_synthesis_filtering
#endif

   Decoding_of_the_coded_Log_Area_Ratios( LARcr, LARpp_j );

   Coefficients_0_12( LARpp_j_1, LARpp_j, LARp );
   LARp_to_rp( LARp );
   FILTER( S, LARp, 13, wt, s );

   Coefficients_13_26( LARpp_j_1, LARpp_j, LARp);
   LARp_to_rp( LARp );
   FILTER( S, LARp, 14, wt + 13, s + 13 );

   Coefficients_27_39( LARpp_j_1, LARpp_j, LARp);
   LARp_to_rp( LARp );
   FILTER( S, LARp, 13, wt + 27, s + 27 );

   Coefficients_40_159( LARpp_j, LARp );
   LARp_to_rp( LARp );
   FILTER(S, LARp, 120, wt + 40, s + 40);
}

P5()

static void Short_term_synthesis_filtering P5 ( (S, rrp, k, wt, sr)  , struct gsm_state *  S, register word *  rrp, register int  k, register word *  wt, register word *  sr  )

static

Definition at line 281 of file short_term.c.

References MAX_WORD, MIN_WORD, S, and gsm_state::v.

{
   register word     * v = S->v;
   register int      i;
   register longword    sri;

   while (k--) {
      sri = *wt++;
      for (i = 8; i--;) {
         register longword    tmp1, tmp2;

         /* sri = GSM_SUB( sri, gsm_mult_r( rrp[i], v[i] ) );
          */
         tmp1 = rrp[i];
         tmp2 = v[i];

         tmp2 = (( tmp1 * tmp2 + 16384) >> 15) ;
         /* saturation done below */
         sri  -= tmp2;
         if (sri != (word)sri) {
            sri = (sri<0)? MIN_WORD:MAX_WORD;
         }
         /* v[i+1] = GSM_ADD( v[i], gsm_mult_r( rrp[i], sri ) );
          */

         tmp1 = (( tmp1 * sri + 16384) >> 15) ;
         /* saturation done below */
         tmp1 += v[i];
         if (tmp1 != (word)tmp1) {
            tmp1 = (tmp1<0)? MIN_WORD:MAX_WORD;
         }
         v[i+1] = (word)tmp1;
      }
      *sr++ = v[0] = (word)sri;
   }
}