FFmpeg
mpegaudio.h
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1 /*
2  * copyright (c) 2001 Fabrice Bellard
3  *
4  * This file is part of FFmpeg.
5  *
6  * FFmpeg is free software; you can redistribute it and/or
7  * modify it under the terms of the GNU Lesser General Public
8  * License as published by the Free Software Foundation; either
9  * version 2.1 of the License, or (at your option) any later version.
10  *
11  * FFmpeg is distributed in the hope that it will be useful,
12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14  * Lesser General Public License for more details.
15  *
16  * You should have received a copy of the GNU Lesser General Public
17  * License along with FFmpeg; if not, write to the Free Software
18  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
19  */
20 
21 /**
22  * @file
23  * mpeg audio declarations for both encoder and decoder.
24  */
25 
26 #ifndef AVCODEC_MPEGAUDIO_H
27 #define AVCODEC_MPEGAUDIO_H
28 
29 #ifndef USE_FLOATS
30 # define USE_FLOATS 0
31 #endif
32 
33 #include <stdint.h>
34 #include "libavutil/internal.h"
35 
36 /* max frame size, in samples */
37 #define MPA_FRAME_SIZE 1152
38 
39 /* max compressed frame size */
40 #define MPA_MAX_CODED_FRAME_SIZE 1792
41 
42 #define MPA_MAX_CHANNELS 2
43 
44 #define SBLIMIT 32 /* number of subbands */
45 
46 #define MPA_STEREO 0
47 #define MPA_JSTEREO 1
48 #define MPA_DUAL 2
49 #define MPA_MONO 3
50 
51 #ifndef FRAC_BITS
52 #define FRAC_BITS 23 /* fractional bits for sb_samples and dct */
53 #define WFRAC_BITS 16 /* fractional bits for window */
54 #endif
55 
56 #define IMDCT_SCALAR 1.759
57 
58 #define FRAC_ONE (1 << FRAC_BITS)
59 
60 #define FIX(a) ((int)((a) * FRAC_ONE))
61 
62 #if USE_FLOATS
63 # define INTFLOAT float
64 # define SUINTFLOAT float
65 typedef float MPA_INT;
66 typedef float OUT_INT;
67 #elif FRAC_BITS <= 15
68 # define INTFLOAT int
69 # define SUINTFLOAT SUINT
70 typedef int16_t MPA_INT;
71 typedef int16_t OUT_INT;
72 #else
73 # define INTFLOAT int
74 # define SUINTFLOAT SUINT
75 typedef int32_t MPA_INT;
76 typedef int16_t OUT_INT;
77 #endif
78 
79 int ff_mpa_l2_select_table(int bitrate, int nb_channels, int freq, int lsf);
80 
81 #endif /* AVCODEC_MPEGAUDIO_H */
int32_t MPA_INT
Definition: mpegaudio.h:75
int16_t OUT_INT
Definition: mpegaudio.h:76
int ff_mpa_l2_select_table(int bitrate, int nb_channels, int freq, int lsf)
Definition: mpegaudio.c:31
common internal API header
int32_t
int64_t bitrate
Definition: h264_levels.c:131
int nb_channels