1 /*****************************************************************************
2 * audio_output.h : audio output thread interface
3 *****************************************************************************
4 * Copyright (C) 1999, 2000 VideoLAN
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License as published by
10 * the Free Software Foundation; either version 2 of the License, or
11 * (at your option) any later version.
13 * This program is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16 * General Public License for more details.
18 * You should have received a copy of the GNU General Public
19 * License along with this program; if not, write to the
20 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
21 * Boston, MA 02111-1307, USA.
22 *****************************************************************************/
24 /*****************************************************************************
26 * - <sys/soundcard.h> ( audio_buf_info )
27 * - "common.h" ( boolean_t )
28 * - "mtime.h" ( mtime_t )
29 * - "threads.h" ( vlc_thread_t )
30 *****************************************************************************/
34 * - Créer un flag destroy dans les fifos audio pour indiquer au thread audio
35 * qu'il peut libérer la mémoire occupée par le buffer de la fifo lorsqu'il
36 * le désire (fin du son ou fin du thread)
37 * - Redéplacer les #define dans config.h
42 * Defines => "config.h"
45 /* Default output device. You probably should not change this. */
46 #define AOUT_DEFAULT_DEVICE "/dev/dsp"
48 /* Default audio output format (AOUT_FMT_S16_NE = Native Endianess) */
49 #define AOUT_DEFAULT_FORMAT AOUT_FMT_S16_NE
51 /* #define AOUT_DEFAULT_FORMAT AOUT_FMT_S8 */
52 /* #define AOUT_DEFAULT_FORMAT AOUT_FMT_U8 */
53 /* #define AOUT_DEFAULT_FORMAT AOUT_FMT_S16_BE */
54 /* #define AOUT_DEFAULT_FORMAT AOUT_FMT_S16_LE */
55 /* #define AOUT_DEFAULT_FORMAT AOUT_FMT_U16_BE */
56 /* #define AOUT_DEFAULT_FORMAT AOUT_FMT_U16_LE */
59 /* Default stereo mode (0 stands for mono, 1 for stereo) */
60 #define AOUT_DEFAULT_STEREO 1
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
67 /* Number of audio output frames contained in an audio output fifo.
68 * (AOUT_FIFO_SIZE + 1) must be a power of 2, in order to optimise the
69 * %(AOUT_FIFO_SIZE + 1) operation with an &AOUT_FIFO_SIZE.
70 * With 511 we have at least 511*384/2/48000=2 seconds of sound */
71 #define AOUT_FIFO_SIZE 511
73 /* Maximum number of audio fifos. The value of AOUT_MAX_FIFOS should be a power
74 * of two, in order to optimize the '/AOUT_MAX_FIFOS' and '*AOUT_MAX_FIFOS'
75 * operations with '>>' and '<<' (gcc changes this at compilation-time) */
76 #define AOUT_MAX_FIFOS 2
78 /* Duration (in microseconds) of an audio output buffer should be :
79 * - short, in order to be able to play a new song very quickly (especially a
80 * song from the interface)
81 * - long, in order to perform the buffer calculations as few as possible */
82 #define AOUT_BUFFER_DURATION 100000
87 #define AOUT_FIFO_ISEMPTY( fifo ) ( (fifo).l_end_frame == (fifo).i_start_frame )
88 #define AOUT_FIFO_ISFULL( fifo ) ( ((((fifo).l_end_frame + 1) - (fifo).l_start_frame) & AOUT_FIFO_SIZE) == 0 )
90 /*****************************************************************************
92 *****************************************************************************
93 * This structure is used to keep the progression of an index up-to-date, in
94 * order to avoid rounding problems and heavy computations, as the function
95 * that handles this structure only uses additions.
96 *****************************************************************************/
99 /* The remainder is used to keep track of the fractional part of the
104 * The increment structure is initialized with the result of an euclidean
107 * l_euclidean_numerator l_euclidean_remainder
108 * ----------------------- = l_euclidean_integer + -----------------------
109 * l_euclidean_denominator l_euclidean_denominator
112 long l_euclidean_integer;
113 long l_euclidean_remainder;
114 long l_euclidean_denominator;
118 /*****************************************************************************
120 *****************************************************************************/
123 /* See the fifo types below */
131 vlc_mutex_t data_lock;
132 vlc_cond_t data_wait;
137 /* The start frame is the first frame in the buffer that contains decoded
138 * audio data. It it also the first frame in the current timestamped frame
139 * area, ie the first dated frame in the decoded part of the buffer. :-p */
141 boolean_t b_start_frame;
142 /* The next frame is the end frame of the current timestamped frame area,
143 * ie the first dated frame after the start frame. */
145 boolean_t b_next_frame;
146 /* The end frame is the first frame, after the start frame, that doesn't
147 * contain decoded audio data. That's why the end frame is the first frame
148 * where the audio decoder can store its decoded audio frames. */
152 aout_increment_t unit_increment;
153 /* The following variable is used to store the number of remaining audio
154 * units in the current timestamped frame area. */
159 #define AOUT_EMPTY_FIFO 0
160 #define AOUT_INTF_MONO_FIFO 1
161 #define AOUT_INTF_STEREO_FIFO 2
162 #define AOUT_ADEC_MONO_FIFO 3
163 #define AOUT_ADEC_STEREO_FIFO 4
165 /*****************************************************************************
166 * aout_thread_t : audio output thread descriptor
167 *****************************************************************************/
168 typedef int (aout_sys_open_t) ( p_aout_thread_t p_aout );
169 typedef int (aout_sys_reset_t) ( p_aout_thread_t p_aout );
170 typedef int (aout_sys_setformat_t) ( p_aout_thread_t p_aout );
171 typedef int (aout_sys_setchannels_t) ( p_aout_thread_t p_aout );
172 typedef int (aout_sys_setrate_t) ( p_aout_thread_t p_aout );
173 typedef long (aout_sys_getbufinfo_t) ( p_aout_thread_t p_aout,
174 long l_buffer_limit );
175 typedef void (aout_sys_playsamples_t) ( p_aout_thread_t p_aout,
176 byte_t *buffer, int i_size );
177 typedef void (aout_sys_close_t) ( p_aout_thread_t p_aout );
179 typedef struct aout_thread_s
181 vlc_thread_t thread_id;
184 vlc_mutex_t fifos_lock;
185 aout_fifo_t fifo[ AOUT_MAX_FIFOS ];
188 void * p_aout_plugin; /* video output plugin */
189 aout_sys_open_t * p_sys_open;
190 aout_sys_reset_t * p_sys_reset;
191 aout_sys_setformat_t * p_sys_setformat;
192 aout_sys_setchannels_t * p_sys_setchannels;
193 aout_sys_setrate_t * p_sys_setrate;
194 aout_sys_getbufinfo_t * p_sys_getbufinfo;
195 aout_sys_playsamples_t * p_sys_playsamples;
196 aout_sys_close_t * p_sys_close;
199 /* The s32 buffer is used to mix all the audio fifos together before
200 * converting them and storing them in the audio output buffer */
203 /* The size of the audio output buffer is kept in audio units, as this is
204 * the only unit that is common with every audio decoder and audio fifo */
208 /* date is the moment where the first audio unit of the output buffer
212 /* Path to the audio output device (default is set to "/dev/dsp") */
216 /* Format of the audio output samples */
218 /* Number of channels */
220 /* Mono or Stereo sound */
222 /* Rate and gain of the audio output sound (in Hz) */
226 /* there might be some useful private structure, such as audio_buf_info
227 * for the OSS output */
232 /* Those are from <linux/soundcard.h> but are needed because of formats
233 * on other platforms */
234 #define AOUT_FMT_U8 0x00000008
235 #define AOUT_FMT_S16_LE 0x00000010 /* Little endian signed 16 */
236 #define AOUT_FMT_S16_BE 0x00000020 /* Big endian signed 16 */
237 #define AOUT_FMT_S8 0x00000040
238 #define AOUT_FMT_U16_LE 0x00000080 /* Little endian U16 */
239 #define AOUT_FMT_U16_BE 0x00000100 /* Big endian U16 */
241 #if __BYTE_ORDER == __LITTLE_ENDIAN
242 #define AOUT_FMT_S16_NE AOUT_FMT_S16_LE
243 #elif __BYTE_ORDER == __BIG_ENDIAN
244 #define AOUT_FMT_S16_NE AOUT_FMT_S16_BE
247 /*****************************************************************************
249 *****************************************************************************/
250 aout_thread_t * aout_CreateThread ( int *pi_status );
251 void aout_DestroyThread ( aout_thread_t *p_aout, int *pi_status );
254 aout_fifo_t * aout_CreateFifo ( aout_thread_t *p_aout, aout_fifo_t *p_fifo );
255 void aout_DestroyFifo ( aout_fifo_t *p_fifo );