FreeCalypso > hg > gsm-codec-lib
changeset 326:bfe74a9edd5a
libtwamr: integrate log2.c
| author | Mychaela Falconia <falcon@freecalypso.org> |
|---|---|
| date | Thu, 18 Apr 2024 20:21:04 +0000 |
| parents | 67c31802392b |
| children | 2df212a012af |
| files | libtwamr/Makefile libtwamr/log2.c libtwamr/log2.h libtwamr/log2.tab libtwamr/namespace.h |
| diffstat | 5 files changed, 196 insertions(+), 1 deletions(-) [+] |
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--- a/libtwamr/Makefile Thu Apr 18 20:12:48 2024 +0000 +++ b/libtwamr/Makefile Thu Apr 18 20:21:04 2024 +0000 @@ -3,7 +3,8 @@ OBJS= a_refl.o agc.o autocorr.o az_lsp.o b_cn_cod.o basicop2.o bgnscd.o \ bitno.o bits2prm.o c1035pf.o c2_11pf.o c2_9pf.o c3_14pf.o c4_17pf.o \ c8_31pf.o c_g_aver.o calc_cor.o cor_h.o gmed_n.o graytab.o inv_sqrt.o \ - oper_32b.o prmno.o s10_8pf.o set_sign.o sqrt_l.o tls_flags.o window.o + log2.o oper_32b.o prmno.o s10_8pf.o set_sign.o sqrt_l.o tls_flags.o \ + window.o LIB= libtwamr.a INSTALL_PREFIX= /usr/local
--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/libtwamr/log2.c Thu Apr 18 20:21:04 2024 +0000 @@ -0,0 +1,122 @@ +/* +******************************************************************************** +* +* 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 : log2.c +* Purpose : Computes log2(L_x) +* +******************************************************************************** +*/ +/* +******************************************************************************** +* MODULE INCLUDE FILE AND VERSION ID +******************************************************************************** +*/ +#include "namespace.h" +#include "log2.h" + +/* +******************************************************************************** +* INCLUDE FILES +******************************************************************************** +*/ +#include "typedef.h" +#include "basic_op.h" +#include "no_count.h" + +/* +******************************************************************************** +* LOCAL VARIABLES AND TABLES +******************************************************************************** +*/ +#include "log2.tab" /* Table for Log2() */ + +/* +******************************************************************************** +* PUBLIC PROGRAM CODE +******************************************************************************** +*/ + +/************************************************************************* + * + * FUNCTION: Log2_norm() + * + * PURPOSE: Computes log2(L_x, exp), where L_x is positive and + * normalized, and exp is the normalisation exponent + * If L_x is negative or zero, the result is 0. + * + * DESCRIPTION: + * The function Log2(L_x) is approximated by a table and linear + * interpolation. The following steps are used to compute Log2(L_x) + * + * 1- exponent = 30-norm_exponent + * 2- i = bit25-b31 of L_x; 32<=i<=63 (because of normalization). + * 3- a = bit10-b24 + * 4- i -=32 + * 5- fraction = table[i]<<16 - (table[i] - table[i+1]) * a * 2 + * + *************************************************************************/ +void Log2_norm ( + Word32 L_x, /* (i) : input value (normalized) */ + Word16 exp, /* (i) : norm_l (L_x) */ + Word16 *exponent, /* (o) : Integer part of Log2. (range: 0<=val<=30) */ + Word16 *fraction /* (o) : Fractional part of Log2. (range: 0<=val<1) */ +) +{ + Word16 i, a, tmp; + Word32 L_y; + + test (); + if (L_x <= (Word32) 0) + { + *exponent = 0; move16 (); + *fraction = 0; move16 (); + return; + } + + *exponent = sub (30, exp); move16 (); + + L_x = L_shr (L_x, 9); + i = extract_h (L_x); /* Extract b25-b31 */ + L_x = L_shr (L_x, 1); + a = extract_l (L_x); /* Extract b10-b24 of fraction */ + a = a & (Word16) 0x7fff; logic16 (); + + i = sub (i, 32); + + L_y = L_deposit_h (table[i]); /* table[i] << 16 */ + tmp = sub (table[i], table[i + 1]); /* table[i] - table[i+1] */ + L_y = L_msu (L_y, tmp, a); /* L_y -= tmp*a*2 */ + + *fraction = extract_h (L_y);move16 (); + + return; +} + +/************************************************************************* + * + * FUNCTION: Log2() + * + * PURPOSE: Computes log2(L_x), where L_x is positive. + * If L_x is negative or zero, the result is 0. + * + * DESCRIPTION: + * normalizes L_x and then calls Log2_norm(). + * + *************************************************************************/ +void Log2 ( + Word32 L_x, /* (i) : input value */ + Word16 *exponent, /* (o) : Integer part of Log2. (range: 0<=val<=30) */ + Word16 *fraction /* (o) : Fractional part of Log2. (range: 0<=val<1) */ +) +{ + Word16 exp; + + exp = norm_l (L_x); + Log2_norm (L_shl (L_x, exp), exp, exponent, fraction); +}
--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/libtwamr/log2.h Thu Apr 18 20:21:04 2024 +0000 @@ -0,0 +1,49 @@ +/* +******************************************************************************** +* +* 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 : log2.h +* Purpose : Computes log2(L_x) +* +******************************************************************************** +*/ +#ifndef log2_h +#define log2_h "$Id $" + +/* +******************************************************************************** +* INCLUDE FILES +******************************************************************************** +*/ +#include "typedef.h" + +/* +******************************************************************************** +* DEFINITION OF DATA TYPES +******************************************************************************** +*/ + +/* +******************************************************************************** +* DECLARATION OF PROTOTYPES +******************************************************************************** +*/ +void Log2 ( + Word32 L_x, /* (i) : input value */ + Word16 *exponent, /* (o) : Integer part of Log2. (range: 0<=val<=30) */ + Word16 *fraction /* (o) : Fractional part of Log2. (range: 0<=val<1)*/ +); + +void Log2_norm ( + Word32 L_x, /* (i) : input value (normalized) */ + Word16 exp, /* (i) : norm_l (L_x) */ + Word16 *exponent, /* (o) : Integer part of Log2. (range: 0<=val<=30) */ + Word16 *fraction /* (o) : Fractional part of Log2. (range: 0<=val<1) */ +); + +#endif
--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/libtwamr/log2.tab Thu Apr 18 20:21:04 2024 +0000 @@ -0,0 +1,22 @@ +/* +******************************************************************************** +* +* 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 : log2.tab +* Purpose : Table for routine Log2(). +* $Id $ +* +******************************************************************************** +*/ +static const Word16 table[33] = +{ + 0, 1455, 2866, 4236, 5568, 6863, 8124, 9352, 10549, 11716, + 12855, 13967, 15054, 16117, 17156, 18172, 19167, 20142, 21097, 22033, + 22951, 23852, 24735, 25603, 26455, 27291, 28113, 28922, 29716, 30497, + 31266, 32023, 32767 +};