FreeCalypso > hg > gsm-codec-lib
view libtwamr/set_sign.c @ 457:9bcf65088006
doc/AMR-EFR-philosophy: document implemented solution
author | Mychaela Falconia <falcon@freecalypso.org> |
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date | Fri, 10 May 2024 18:20:06 +0000 |
parents | 15c354f75110 |
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/* ******************************************************************************** * * GSM AMR-NB speech codec R98 Version 7.6.0 December 12, 2001 * R99 Version 3.3.0 * REL-4 Version 4.1.0 * ******************************************************************************** * * File : set_sign.c * Purpose : Builds sign vector according to "dn[]" and "cn[]". * ******************************************************************************** */ /* ******************************************************************************** * MODULE INCLUDE FILE AND VERSION ID ******************************************************************************** */ #include "namespace.h" #include "set_sign.h" /* ******************************************************************************** * INCLUDE FILES ******************************************************************************** */ #include "typedef.h" #include "basic_op.h" #include "no_count.h" #include "inv_sqrt.h" #include "cnst.h" /* ******************************************************************************** * PUBLIC PROGRAM CODE ******************************************************************************** */ /************************************************************************* * * FUNCTION set_sign() * * PURPOSE: Builds sign[] vector according to "dn[]" and "cn[]". * Also finds the position of maximum of correlation in each track * and the starting position for each pulse. * *************************************************************************/ void set_sign(Word16 dn[], /* i/o : correlation between target and h[] */ Word16 sign[], /* o : sign of dn[] */ Word16 dn2[], /* o : maximum of correlation in each track. */ Word16 n /* i : # of maximum correlations in dn2[] */ ) { Word16 i, j, k; Word16 val, min; Word16 pos = 0; /* initialization only needed to keep gcc silent */ /* set sign according to dn[] */ for (i = 0; i < L_CODE; i++) { val = dn[i]; move16 (); test (); if (val >= 0) { sign[i] = 32767; move16 (); } else { sign[i] = -32767; move16 (); val = negate(val); } dn[i] = val; move16 (); /* modify dn[] according to the fixed sign */ dn2[i] = val; move16 (); } /* keep 8-n maximum positions/8 of each track and store it in dn2[] */ for (i = 0; i < NB_TRACK; i++) { for (k = 0; k < (8-n); k++) { min = 0x7fff; move16 (); for (j = i; j < L_CODE; j += STEP) { test (); move16 (); if (dn2[j] >= 0) { val = sub(dn2[j], min); test (); if (val < 0) { min = dn2[j]; move16 (); pos = j; move16 (); } } } dn2[pos] = -1; move16 (); } } return; } /************************************************************************* * * FUNCTION set_sign12k2() * * PURPOSE: Builds sign[] vector according to "dn[]" and "cn[]", and modifies * dn[] to include the sign information (dn[i]=sign[i]*dn[i]). * Also finds the position of maximum of correlation in each track * and the starting position for each pulse. * *************************************************************************/ void set_sign12k2 ( Word16 dn[], /* i/o : correlation between target and h[] */ Word16 cn[], /* i : residual after long term prediction */ Word16 sign[], /* o : sign of d[n] */ Word16 pos_max[], /* o : position of maximum correlation */ Word16 nb_track, /* i : number of tracks tracks */ Word16 ipos[], /* o : starting position for each pulse */ Word16 step /* i : the step size in the tracks */ ) { Word16 i, j; Word16 val, cor, k_cn, k_dn, max, max_of_all; Word16 pos = 0; /* initialization only needed to keep gcc silent */ Word16 en[L_CODE]; /* correlation vector */ Word32 s; /* calculate energy for normalization of cn[] and dn[] */ s = 256; move32 (); for (i = 0; i < L_CODE; i++) { s = L_mac (s, cn[i], cn[i]); } s = Inv_sqrt (s); move32 (); k_cn = extract_h (L_shl (s, 5)); s = 256; move32 (); for (i = 0; i < L_CODE; i++) { s = L_mac (s, dn[i], dn[i]); } s = Inv_sqrt (s); move32 (); k_dn = extract_h (L_shl (s, 5)); for (i = 0; i < L_CODE; i++) { val = dn[i]; move16 (); cor = round (L_shl (L_mac (L_mult (k_cn, cn[i]), k_dn, val), 10)); test (); if (cor >= 0) { sign[i] = 32767; move16 (); /* sign = +1 */ } else { sign[i] = -32767; move16 (); /* sign = -1 */ cor = negate (cor); val = negate (val); } /* modify dn[] according to the fixed sign */ dn[i] = val; move16 (); en[i] = cor; move16 (); } max_of_all = -1; move16 (); for (i = 0; i < nb_track; i++) { max = -1; move16 (); for (j = i; j < L_CODE; j += step) { cor = en[j]; move16 (); val = sub (cor, max); test (); if (val > 0) { max = cor; move16 (); pos = j; move16 (); } } /* store maximum correlation position */ pos_max[i] = pos; move16 (); val = sub (max, max_of_all); test (); if (val > 0) { max_of_all = max; move16 (); /* starting position for i0 */ ipos[0] = i; move16 (); } } /*----------------------------------------------------------------* * Set starting position of each pulse. * *----------------------------------------------------------------*/ pos = ipos[0]; move16 (); ipos[nb_track] = pos; move16 (); for (i = 1; i < nb_track; i++) { pos = add (pos, 1); test (); if (sub (pos, nb_track) >= 0) { pos = 0; move16 (); } ipos[i] = pos; move16 (); ipos[add(i, nb_track)] = pos; move16 (); } }