1 /*****************************************************************************
2 * audio_output.h : audio output interface
3 *****************************************************************************
4 * Copyright (C) 2002 VideoLAN
5 * $Id: audio_output.h,v 1.61 2002/08/21 22:41:59 massiot Exp $
7 * Authors: Christophe Massiot <massiot@via.ecp.fr>
9 * This program is free software; you can redistribute it and/or modify
10 * it under the terms of the GNU General Public License as published by
11 * the Free Software Foundation; either version 2 of the License, or
12 * (at your option) any later version.
14 * This program is distributed in the hope that it will be useful,
15 * but WITHOUT ANY WARRANTY; without even the implied warranty of
16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 * GNU General Public License for more details.
19 * You should have received a copy of the GNU General Public License
20 * along with this program; if not, write to the Free Software
21 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111, USA.
22 *****************************************************************************/
24 /*****************************************************************************
25 * audio_sample_format_t
26 *****************************************************************************
27 * This structure defines a format for audio samples.
28 *****************************************************************************/
29 struct audio_sample_format_t
34 /* Optional - for A52, SPDIF and DTS types */
35 int i_bytes_per_frame;
37 /* Please note that it may be completely arbitrary - buffers are not
38 * obliged to contain a integral number of so-called "frames". It's
39 * just here for the division :
40 * i_nb_samples * i_bytes_per_frame / i_frame_length */
43 #define AOUT_FMT_MU_LAW 0x00000001
44 #define AOUT_FMT_A_LAW 0x00000002
45 #define AOUT_FMT_IMA_ADPCM 0x00000004
46 #define AOUT_FMT_U8 0x00000008
47 #define AOUT_FMT_S16_LE 0x00000010 /* Little endian signed 16 */
48 #define AOUT_FMT_S16_BE 0x00000020 /* Big endian signed 16 */
49 #define AOUT_FMT_S8 0x00000040
50 #define AOUT_FMT_U16_LE 0x00000080 /* Little endian U16 */
51 #define AOUT_FMT_U16_BE 0x00000100 /* Big endian U16 */
52 #define AOUT_FMT_SPDIF 0x00000400 /* S/PDIF hardware support */
53 #define AOUT_FMT_FLOAT32 0x00010000
54 #define AOUT_FMT_FIXED32 0x00020000
55 #define AOUT_FMT_A52 0x00100000
56 #define AOUT_FMT_DTS 0x00200000
58 #define AOUT_FMTS_IDENTICAL( p_first, p_second ) ( \
59 ((p_first)->i_format == (p_second)->i_format) \
60 && ((p_first)->i_rate == (p_second)->i_rate) \
61 && ((p_first)->i_channels == (p_second)->i_channels \
62 || (p_first)->i_channels == -1 || (p_second)->i_channels == -1) )
64 /* Check if i_rate == i_rate and i_channels == i_channels */
65 #define AOUT_FMTS_SIMILAR( p_first, p_second ) ( \
66 ((p_first)->i_rate == (p_second)->i_rate) \
67 && ((p_first)->i_channels == (p_second)->i_channels \
68 || (p_first)->i_channels == -1 || (p_second)->i_channels == -1) )
70 #ifdef WORDS_BIGENDIAN
71 # define AOUT_FMT_S16_NE AOUT_FMT_S16_BE
72 # define AOUT_FMT_U16_NE AOUT_FMT_U16_BE
74 # define AOUT_FMT_S16_NE AOUT_FMT_S16_LE
75 # define AOUT_FMT_U16_NE AOUT_FMT_U16_LE
78 #define AOUT_FMT_NON_LINEAR( p_format ) \
79 ( ((p_format)->i_format == AOUT_FMT_SPDIF) \
80 || ((p_format)->i_format == AOUT_FMT_A52) \
81 || ((p_format)->i_format == AOUT_FMT_DTS) )
83 /* This is heavily borrowed from libmad, by Robert Leslie <rob@mars.org> */
85 * Fixed-point format: 0xABBBBBBB
86 * A == whole part (sign + 3 bits)
87 * B == fractional part (28 bits)
89 * Values are signed two's complement, so the effective range is:
90 * 0x80000000 to 0x7fffffff
91 * -8.0 to +7.9999999962747097015380859375
93 * The smallest representable value is:
94 * 0x00000001 == 0.0000000037252902984619140625 (i.e. about 3.725e-9)
96 * 28 bits of fractional accuracy represent about
97 * 8.6 digits of decimal accuracy.
99 * Fixed-point numbers can be added or subtracted as normal
100 * integers, but multiplication requires shifting the 64-bit result
101 * from 56 fractional bits back to 28 (and rounding.)
103 typedef s32 vlc_fixed_t;
104 #define FIXED32_FRACBITS 28
105 #define FIXED32_MIN ((vlc_fixed_t) -0x80000000L)
106 #define FIXED32_MAX ((vlc_fixed_t) +0x7fffffffL)
107 #define FIXED32_ONE ((vlc_fixed_t) 0x10000000)
110 /*****************************************************************************
111 * aout_buffer_t : audio output buffer
112 *****************************************************************************/
117 /* i_size is the real size of the buffer (used for debug ONLY), i_nb_bytes
118 * is the number of significative bytes in it. */
119 size_t i_size, i_nb_bytes;
121 mtime_t start_date, end_date;
123 struct aout_buffer_t * p_next;
126 /* Size of a frame for S/PDIF output. */
127 #define AOUT_SPDIF_SIZE 6144
129 /*****************************************************************************
130 * audio_date_t : date incrementation without long-term rounding errors
131 *****************************************************************************/
139 /*****************************************************************************
141 *****************************************************************************/
142 /* From audio_output.c : */
143 #define aout_NewInstance(a) __aout_NewInstance(VLC_OBJECT(a))
144 VLC_EXPORT( aout_instance_t *, __aout_NewInstance, ( vlc_object_t * ) );
145 VLC_EXPORT( void, aout_DeleteInstance, ( aout_instance_t * ) );
146 VLC_EXPORT( aout_buffer_t *, aout_BufferNew, ( aout_instance_t *, aout_input_t *, size_t ) );
147 VLC_EXPORT( void, aout_BufferDelete, ( aout_instance_t *, aout_input_t *, aout_buffer_t * ) );
148 VLC_EXPORT( void, aout_BufferPlay, ( aout_instance_t *, aout_input_t *, aout_buffer_t * ) );
149 VLC_EXPORT( void, aout_DateInit, ( audio_date_t *, u32 ) );
150 VLC_EXPORT( void, aout_DateSet, ( audio_date_t *, mtime_t ) );
151 VLC_EXPORT( void, aout_DateMove, ( audio_date_t *, mtime_t ) );
152 VLC_EXPORT( mtime_t, aout_DateGet, ( const audio_date_t * ) );
153 VLC_EXPORT( mtime_t, aout_DateIncrement, ( audio_date_t *, u32 ) );
156 #define aout_InputNew(a,b,c) __aout_InputNew(VLC_OBJECT(a),b,c)
157 VLC_EXPORT( aout_input_t *, __aout_InputNew, ( vlc_object_t *, aout_instance_t **, audio_sample_format_t * ) );
158 VLC_EXPORT( void, aout_InputDelete, ( aout_instance_t *, aout_input_t * ) );