1 /*****************************************************************************
2 * audio_output.h : audio output thread interface
3 *****************************************************************************
4 * Copyright (C) 1999, 2000 VideoLAN
5 * $Id: audio_output.h,v 1.33 2001/05/01 04:18:17 sam Exp $
7 * Authors: Michel Kaempf <maxx@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 /*****************************************************************************
26 *****************************************************************************
27 * This structure is used to keep the progression of an index up-to-date, in
28 * order to avoid rounding problems and heavy computations, as the function
29 * that handles this structure only uses additions.
30 *****************************************************************************/
31 typedef struct aout_increment_s
33 /* The remainder is used to keep track of the fractional part of the
38 * The increment structure is initialized with the result of an euclidean
41 * l_euclidean_numerator l_euclidean_remainder
42 * ----------------------- = l_euclidean_integer + -----------------------
43 * l_euclidean_denominator l_euclidean_denominator
46 long l_euclidean_integer;
47 long l_euclidean_remainder;
48 long l_euclidean_denominator;
52 /*****************************************************************************
54 *****************************************************************************/
55 typedef struct aout_fifo_s
57 /* See the fifo types below */
60 int i_fifo; /* Just to keep track of the fifo index */
66 vlc_mutex_t data_lock;
72 /* The start frame is the first frame in the buffer that contains decoded
73 * audio data. It it also the first frame in the current timestamped frame
74 * area, ie the first dated frame in the decoded part of the buffer. :-p */
76 boolean_t b_start_frame;
77 /* The next frame is the end frame of the current timestamped frame area,
78 * ie the first dated frame after the start frame. */
80 boolean_t b_next_frame;
81 /* The end frame is the first frame, after the start frame, that doesn't
82 * contain decoded audio data. That's why the end frame is the first frame
83 * where the audio decoder can store its decoded audio frames. */
87 aout_increment_t unit_increment;
88 /* The following variable is used to store the number of remaining audio
89 * units in the current timestamped frame area. */
94 #define AOUT_FIFO_ISEMPTY( fifo ) \
95 ( (fifo).l_end_frame == (fifo).l_start_frame )
97 #define AOUT_FIFO_ISFULL( fifo ) \
98 ( ((((fifo).l_end_frame + 1) - (fifo).l_start_frame) & AOUT_FIFO_SIZE) == 0 )
100 #define AOUT_EMPTY_FIFO 0
101 #define AOUT_INTF_MONO_FIFO 1
102 #define AOUT_INTF_STEREO_FIFO 2
103 #define AOUT_ADEC_MONO_FIFO 3
104 #define AOUT_ADEC_STEREO_FIFO 4
105 #define AOUT_ADEC_SPDIF_FIFO 5
107 /*****************************************************************************
108 * aout_thread_t : audio output thread descriptor
109 *****************************************************************************/
110 typedef struct aout_thread_s
112 vlc_thread_t thread_id;
116 vlc_mutex_t fifos_lock;
117 aout_fifo_t fifo[ AOUT_MAX_FIFOS ];
119 /* Plugin used and shortcuts to access its capabilities */
120 struct module_s * p_module;
121 int ( *pf_open ) ( p_aout_thread_t );
122 int ( *pf_setformat ) ( p_aout_thread_t );
123 long ( *pf_getbufinfo ) ( p_aout_thread_t, long );
124 void ( *pf_play ) ( p_aout_thread_t, byte_t *, int );
125 void ( *pf_close ) ( p_aout_thread_t );
128 /* The s32 buffer is used to mix all the audio fifos together before
129 * converting them and storing them in the audio output buffer */
132 /* The size of the audio output buffer is kept in audio units, as this is
133 * the only unit that is common with every audio decoder and audio fifo */
137 /* date is the moment where the first audio unit of the output buffer
141 /* Path to the audio output device (default is set to "/dev/dsp") */
145 /* The current volume */
147 /* Format of the audio output samples */
149 /* Number of channels */
151 /* Mono or Stereo sound */
153 /* Rate and gain of the audio output sound (in Hz) */
157 /* there might be some useful private structure, such as audio_buf_info
158 * for the OSS output */
163 /* Those are from <linux/soundcard.h> but are needed because of formats
164 * on other platforms */
165 #define AOUT_FMT_U8 0x00000008
166 #define AOUT_FMT_S16_LE 0x00000010 /* Little endian signed 16 */
167 #define AOUT_FMT_S16_BE 0x00000020 /* Big endian signed 16 */
168 #define AOUT_FMT_S8 0x00000040
169 #define AOUT_FMT_U16_LE 0x00000080 /* Little endian U16 */
170 #define AOUT_FMT_U16_BE 0x00000100 /* Big endian U16 */
171 #define AOUT_FMT_AC3 0x00000400 /* Dolby Digital AC3 */
174 #ifdef WORDS_BIGENDIAN
175 #define AOUT_FMT_S16_NE AOUT_FMT_S16_BE
177 #define AOUT_FMT_S16_NE AOUT_FMT_S16_LE
180 /*****************************************************************************
182 *****************************************************************************/
183 aout_thread_t * aout_CreateThread ( int *pi_status );
184 void aout_DestroyThread ( aout_thread_t *, int * );
186 aout_fifo_t * aout_CreateFifo ( int, int, long, long, long, void * );
187 void aout_DestroyFifo ( aout_fifo_t *p_fifo );
188 void aout_FreeFifo ( aout_fifo_t *p_fifo );