FreeCalypso > hg > gsm-codec-lib

comparison libtwamr/calc_en.h @ 327:2df212a012af

Find changesets by keywords (author, files, the commit message), revision number or hash, or revset expression.
libtwamr: integrate calc_en.c
author Mychaela Falconia <falcon@freecalypso.org>
date Thu, 18 Apr 2024 20:28:33 +0000
parents
children
comparison
equal deleted inserted replaced
326:bfe74a9edd5a 327:2df212a012af
1 /*
2 ********************************************************************************
3 *
4 * GSM AMR-NB speech codec R98 Version 7.6.0 December 12, 2001
5 * R99 Version 3.3.0
6 * REL-4 Version 4.1.0
7 *
8 ********************************************************************************
9 *
10 * File : calc_en.h
11 * Purpose : calculation of energy coefficients for quantizers
12 *
13 ********************************************************************************
14 */
15 #ifndef calc_en_h
16 #define calc_en_h "$Id $"
17
18 /*
19 ********************************************************************************
20 * INCLUDE FILES
21 ********************************************************************************
22 */
23 #include "tw_amr.h"
24 #include "typedef.h"
25
26 /*
27 ********************************************************************************
28 * DECLARATION OF PROTOTYPES
29 ********************************************************************************
30 */
31
32 /*************************************************************************
33 *
34 * FUNCTION: calc_unfilt_energies
35 *
36 * PURPOSE: calculation of several energy coefficients for unfiltered
37 * excitation signals and the LTP coding gain
38 *
39 * frac_en[0]*2^exp_en[0] = <res res> // LP residual energy
40 * frac_en[1]*2^exp_en[1] = <exc exc> // LTP residual energy
41 * frac_en[2]*2^exp_en[2] = <exc code> // LTP/CB innovation dot product
42 * frac_en[3]*2^exp_en[3] = <lres lres> // LTP residual energy
43 * // (lres = res - gain_pit*exc)
44 * ltpg = log2(LP_res_en / LTP_res_en)
45 *
46 *************************************************************************/
47 void
48 calc_unfilt_energies(
49 Word16 res[], /* i : LP residual, Q0 */
50 Word16 exc[], /* i : LTP excitation (unfiltered), Q0 */
51 Word16 code[], /* i : CB innovation (unfiltered), Q13 */
52 Word16 gain_pit, /* i : pitch gain, Q14 */
53 Word16 L_subfr, /* i : Subframe length */
54
55 Word16 frac_en[], /* o : energy coefficients (3), fraction part, Q15 */
56 Word16 exp_en[], /* o : energy coefficients (3), exponent part, Q0 */
57 Word16 *ltpg /* o : LTP coding gain (log2()), Q13 */
58 );
59
60 /*************************************************************************
61 *
62 * FUNCTION: calc_filt_energies
63 *
64 * PURPOSE: calculation of several energy coefficients for filtered
65 * excitation signals
66 *
67 * Compute coefficients need for the quantization and the optimum
68 * codebook gain gcu (for MR475 only).
69 *
70 * coeff[0] = y1 y1
71 * coeff[1] = -2 xn y1
72 * coeff[2] = y2 y2
73 * coeff[3] = -2 xn y2
74 * coeff[4] = 2 y1 y2
75 *
76 *
77 * gcu = <xn2, y2> / <y2, y2> (0 if <xn2, y2> <= 0)
78 *
79 * Product <y1 y1> and <xn y1> have been computed in G_pitch() and
80 * are in vector g_coeff[].
81 *
82 *************************************************************************/
83 void
84 calc_filt_energies(
85 enum Mode mode, /* i : coder mode */
86 Word16 xn[], /* i : LTP target vector, Q0 */
87 Word16 xn2[], /* i : CB target vector, Q0 */
88 Word16 y1[], /* i : Adaptive codebook, Q0 */
89 Word16 Y2[], /* i : Filtered innovative vector, Q12 */
90 Word16 g_coeff[], /* i : Correlations <xn y1> <y1 y1> */
91 /* computed in G_pitch() */
92
93 Word16 frac_coeff[],/* o : energy coefficients (5), fraction part, Q15 */
94 Word16 exp_coeff[], /* o : energy coefficients (5), exponent part, Q0 */
95 Word16 *cod_gain_frac,/* o: optimum codebook gain (fraction part), Q15 */
96 Word16 *cod_gain_exp /* o: optimum codebook gain (exponent part), Q0 */
97 );
98
99 /*************************************************************************
100 *
101 * FUNCTION: calc_target_energy
102 *
103 * PURPOSE: calculation of target energy
104 *
105 * en = <xn, xn>
106 *
107 *************************************************************************/
108 void
109 calc_target_energy(
110 Word16 xn[], /* i: LTP target vector, Q0 */
111 Word16 *en_exp, /* o: optimum codebook gain (exponent part), Q0 */
112 Word16 *en_frac /* o: optimum codebook gain (fraction part), Q15 */
113 );
114 #endif