1 /*****************************************************************************
2 * audio_output.h : audio output thread interface
3 *****************************************************************************
4 * Copyright (C) 1999, 2000 VideoLAN
7 * 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 * - "common.h" ( boolean_t )
27 * - "mtime.h" ( mtime_t )
28 * - "threads.h" ( vlc_thread_t )
29 *****************************************************************************/
33 * - Créer un flag destroy dans les fifos audio pour indiquer au thread audio
34 * qu'il peut libérer la mémoire occupée par le buffer de la fifo lorsqu'il
35 * le désire (fin du son ou fin du thread)
36 * - Redéplacer les #define dans config.h
41 * Defines => "config.h"
44 /* Default output device. You probably should not change this. */
45 #define AOUT_DEFAULT_DEVICE "/dev/dsp"
47 /* Default audio output format (AOUT_FMT_S16_NE = Native Endianess) */
48 #define AOUT_DEFAULT_FORMAT AOUT_FMT_S16_NE
50 /* #define AOUT_DEFAULT_FORMAT AOUT_FMT_S8 */
51 /* #define AOUT_DEFAULT_FORMAT AOUT_FMT_U8 */
52 /* #define AOUT_DEFAULT_FORMAT AOUT_FMT_S16_BE */
53 /* #define AOUT_DEFAULT_FORMAT AOUT_FMT_S16_LE */
54 /* #define AOUT_DEFAULT_FORMAT AOUT_FMT_U16_BE */
55 /* #define AOUT_DEFAULT_FORMAT AOUT_FMT_U16_LE */
58 /* Default stereo mode (0 stands for mono, 1 for stereo) */
59 #define AOUT_DEFAULT_STEREO 1
60 /* #define AOUT_DEFAULT_STEREO 0 */
62 /* Audio output rate, in Hz */
63 #define AOUT_MIN_RATE 22050 /* XXX?? */
64 #define AOUT_DEFAULT_RATE 44100
65 #define AOUT_MAX_RATE 48000
68 /* Volume (default 100) */
73 /* Number of audio output frames contained in an audio output fifo.
74 * (AOUT_FIFO_SIZE + 1) must be a power of 2, in order to optimise the
75 * %(AOUT_FIFO_SIZE + 1) operation with an &AOUT_FIFO_SIZE.
76 * With 511 we have at least 511*384/2/48000=2 seconds of sound */
77 #define AOUT_FIFO_SIZE 511
79 /* Maximum number of audio fifos. The value of AOUT_MAX_FIFOS should be a power
80 * of two, in order to optimize the '/AOUT_MAX_FIFOS' and '*AOUT_MAX_FIFOS'
81 * operations with '>>' and '<<' (gcc changes this at compilation-time) */
82 #define AOUT_MAX_FIFOS 2
84 /* Duration (in microseconds) of an audio output buffer should be :
85 * - short, in order to be able to play a new song very quickly (especially a
86 * song from the interface)
87 * - long, in order to perform the buffer calculations as few as possible */
88 #define AOUT_BUFFER_DURATION 100000
93 #define AOUT_FIFO_ISEMPTY( fifo ) ( (fifo).l_end_frame == (fifo).i_start_frame )
94 #define AOUT_FIFO_ISFULL( fifo ) ( ((((fifo).l_end_frame + 1) - (fifo).l_start_frame) & AOUT_FIFO_SIZE) == 0 )
96 /*****************************************************************************
98 *****************************************************************************
99 * This structure is used to keep the progression of an index up-to-date, in
100 * order to avoid rounding problems and heavy computations, as the function
101 * that handles this structure only uses additions.
102 *****************************************************************************/
105 /* The remainder is used to keep track of the fractional part of the
110 * The increment structure is initialized with the result of an euclidean
113 * l_euclidean_numerator l_euclidean_remainder
114 * ----------------------- = l_euclidean_integer + -----------------------
115 * l_euclidean_denominator l_euclidean_denominator
118 long l_euclidean_integer;
119 long l_euclidean_remainder;
120 long l_euclidean_denominator;
124 /*****************************************************************************
126 *****************************************************************************/
129 /* See the fifo types below */
137 vlc_mutex_t data_lock;
138 vlc_cond_t data_wait;
143 /* The start frame is the first frame in the buffer that contains decoded
144 * audio data. It it also the first frame in the current timestamped frame
145 * area, ie the first dated frame in the decoded part of the buffer. :-p */
147 boolean_t b_start_frame;
148 /* The next frame is the end frame of the current timestamped frame area,
149 * ie the first dated frame after the start frame. */
151 boolean_t b_next_frame;
152 /* The end frame is the first frame, after the start frame, that doesn't
153 * contain decoded audio data. That's why the end frame is the first frame
154 * where the audio decoder can store its decoded audio frames. */
158 aout_increment_t unit_increment;
159 /* The following variable is used to store the number of remaining audio
160 * units in the current timestamped frame area. */
165 #define AOUT_EMPTY_FIFO 0
166 #define AOUT_INTF_MONO_FIFO 1
167 #define AOUT_INTF_STEREO_FIFO 2
168 #define AOUT_ADEC_MONO_FIFO 3
169 #define AOUT_ADEC_STEREO_FIFO 4
171 /*****************************************************************************
172 * aout_thread_t : audio output thread descriptor
173 *****************************************************************************/
174 typedef int (aout_sys_open_t) ( p_aout_thread_t p_aout );
175 typedef int (aout_sys_reset_t) ( p_aout_thread_t p_aout );
176 typedef int (aout_sys_setformat_t) ( p_aout_thread_t p_aout );
177 typedef int (aout_sys_setchannels_t) ( p_aout_thread_t p_aout );
178 typedef int (aout_sys_setrate_t) ( p_aout_thread_t p_aout );
179 typedef long (aout_sys_getbufinfo_t) ( p_aout_thread_t p_aout,
180 long l_buffer_limit );
181 typedef void (aout_sys_playsamples_t) ( p_aout_thread_t p_aout,
182 byte_t *buffer, int i_size );
183 typedef void (aout_sys_close_t) ( p_aout_thread_t p_aout );
185 typedef struct aout_thread_s
187 vlc_thread_t thread_id;
191 vlc_mutex_t fifos_lock;
192 aout_fifo_t fifo[ AOUT_MAX_FIFOS ];
195 aout_sys_open_t * p_sys_open;
196 aout_sys_reset_t * p_sys_reset;
197 aout_sys_setformat_t * p_sys_setformat;
198 aout_sys_setchannels_t * p_sys_setchannels;
199 aout_sys_setrate_t * p_sys_setrate;
200 aout_sys_getbufinfo_t * p_sys_getbufinfo;
201 aout_sys_playsamples_t * p_sys_playsamples;
202 aout_sys_close_t * p_sys_close;
205 /* The s32 buffer is used to mix all the audio fifos together before
206 * converting them and storing them in the audio output buffer */
209 /* The size of the audio output buffer is kept in audio units, as this is
210 * the only unit that is common with every audio decoder and audio fifo */
214 /* date is the moment where the first audio unit of the output buffer
218 /* Path to the audio output device (default is set to "/dev/dsp") */
222 /* Format of the audio output samples */
224 /* Number of channels */
226 /* Mono or Stereo sound */
228 /* Rate and gain of the audio output sound (in Hz) */
232 /* there might be some useful private structure, such as audio_buf_info
233 * for the OSS output */
237 /* there is the current volume */
242 /* Those are from <linux/soundcard.h> but are needed because of formats
243 * on other platforms */
244 #define AOUT_FMT_U8 0x00000008
245 #define AOUT_FMT_S16_LE 0x00000010 /* Little endian signed 16 */
246 #define AOUT_FMT_S16_BE 0x00000020 /* Big endian signed 16 */
247 #define AOUT_FMT_S8 0x00000040
248 #define AOUT_FMT_U16_LE 0x00000080 /* Little endian U16 */
249 #define AOUT_FMT_U16_BE 0x00000100 /* Big endian U16 */
251 #if __BYTE_ORDER == __LITTLE_ENDIAN
252 #define AOUT_FMT_S16_NE AOUT_FMT_S16_LE
253 #elif __BYTE_ORDER == __BIG_ENDIAN
254 #define AOUT_FMT_S16_NE AOUT_FMT_S16_BE
257 /*****************************************************************************
259 *****************************************************************************/
260 aout_thread_t * aout_CreateThread ( int *pi_status );
261 void aout_DestroyThread ( aout_thread_t *p_aout, int *pi_status );
264 aout_fifo_t * aout_CreateFifo ( aout_thread_t *p_aout, aout_fifo_t *p_fifo );
265 void aout_DestroyFifo ( aout_fifo_t *p_fifo );