]> git.saurik.com Git - wxWidgets.git/blame - contrib/include/wx/mmedia/internal/g72x.h
More name changes
[wxWidgets.git] / contrib / include / wx / mmedia / internal / g72x.h
CommitLineData
e8482f24
GL
1/*
2 * This source code is a product of Sun Microsystems, Inc. and is provided
3 * for unrestricted use. Users may copy or modify this source code without
4 * charge.
5 *
6 * SUN SOURCE CODE IS PROVIDED AS IS WITH NO WARRANTIES OF ANY KIND INCLUDING
7 * THE WARRANTIES OF DESIGN, MERCHANTIBILITY AND FITNESS FOR A PARTICULAR
8 * PURPOSE, OR ARISING FROM A COURSE OF DEALING, USAGE OR TRADE PRACTICE.
9 *
10 * Sun source code is provided with no support and without any obligation on
11 * the part of Sun Microsystems, Inc. to assist in its use, correction,
12 * modification or enhancement.
13 *
14 * SUN MICROSYSTEMS, INC. SHALL HAVE NO LIABILITY WITH RESPECT TO THE
15 * INFRINGEMENT OF COPYRIGHTS, TRADE SECRETS OR ANY PATENTS BY THIS SOFTWARE
16 * OR ANY PART THEREOF.
17 *
18 * In no event will Sun Microsystems, Inc. be liable for any lost revenue
19 * or profits or other special, indirect and consequential damages, even if
20 * Sun has been advised of the possibility of such damages.
21 *
22 * Sun Microsystems, Inc.
23 * 2550 Garcia Avenue
24 * Mountain View, California 94043
25 */
26
27/*
28 * g72x.h
29 *
30 * Header file for CCITT conversion routines.
31 *
32 */
33#ifndef _G72X_H
34#define _G72X_H
35
36#define AUDIO_ENCODING_ULAW (1) /* ISDN u-law */
37#define AUDIO_ENCODING_ALAW (2) /* ISDN A-law */
38#define AUDIO_ENCODING_LINEAR (3) /* PCM 2's-complement (0-center) */
39
40/*
41 * The following is the definition of the state structure
42 * used by the G.721/G.723 encoder and decoder to preserve their internal
43 * state between successive calls. The meanings of the majority
44 * of the state structure fields are explained in detail in the
45 * CCITT Recommendation G.721. The field names are essentially indentical
46 * to variable names in the bit level description of the coding algorithm
47 * included in this Recommendation.
48 */
49struct g72x_state {
50 long yl; /* Locked or steady state step size multiplier. */
51 short yu; /* Unlocked or non-steady state step size multiplier. */
52 short dms; /* Short term energy estimate. */
53 short dml; /* Long term energy estimate. */
54 short ap; /* Linear weighting coefficient of 'yl' and 'yu'. */
55
56 short a[2]; /* Coefficients of pole portion of prediction filter. */
57 short b[6]; /* Coefficients of zero portion of prediction filter. */
58 short pk[2]; /*
59 * Signs of previous two samples of a partially
60 * reconstructed signal.
61 */
62 short dq[6]; /*
63 * Previous 6 samples of the quantized difference
64 * signal represented in an internal floating point
65 * format.
66 */
67 short sr[2]; /*
68 * Previous 2 samples of the quantized difference
69 * signal represented in an internal floating point
70 * format.
71 */
72 char td; /* delayed tone detect, new in 1988 version */
73};
74
75/* External function definitions. */
76
77extern unsigned char linear2alaw (int pcm_val); /* 2's complement (16-bit range) */
78extern int alaw2linear (unsigned char a_val);
79extern unsigned char linear2ulaw (int pcm_val); /* 2's complement (16-bit range) */
80extern int ulaw2linear (unsigned char u_val);
81extern int predictor_zero (struct g72x_state *state_ptr);
82extern int predictor_pole (struct g72x_state *state_ptr);
83extern int step_size (struct g72x_state *state_ptr);
84extern int quantize (int d, int y, short *table, int size);
85extern int reconstruct (int sign, int dqln, int y);
86
87extern void update
88 ( int code_size, int y, int wi, int fi, int dq
89 , int sr, int dqsez, struct g72x_state *state_ptr);
90
91int tandem_adjust_alaw
92 (int sr, int se, int y, int i, int sign, short *qtab);
93
94int tandem_adjust_ulaw
95 (int sr, int se, int y, int i, int sign, short *qtab);
96
97extern void g72x_init_state (struct g72x_state *);
98extern int g721_encoder(
99 int sample,
100 int in_coding,
101 struct g72x_state *state_ptr);
102extern int g721_decoder(
103 int code,
104 int out_coding,
105 struct g72x_state *state_ptr);
106extern int g723_24_encoder(
107 int sample,
108 int in_coding,
109 struct g72x_state *state_ptr);
110extern int g723_24_decoder(
111 int code,
112 int out_coding,
113 struct g72x_state *state_ptr);
114extern int g723_40_encoder(
115 int sample,
116 int in_coding,
117 struct g72x_state *state_ptr);
118extern int g723_40_decoder(
119 int code,
120 int out_coding,
121 struct g72x_state *state_ptr);
122
123#endif /* !_G72X_H */