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)
42 #define AOUT_FIFO_ISEMPTY( fifo ) ( (fifo).l_end_frame == (fifo).i_start_frame )
43 #define AOUT_FIFO_ISFULL( fifo ) ( ((((fifo).l_end_frame + 1) - (fifo).l_start_frame) & AOUT_FIFO_SIZE) == 0 )
45 /*****************************************************************************
47 *****************************************************************************
48 * This structure is used to keep the progression of an index up-to-date, in
49 * order to avoid rounding problems and heavy computations, as the function
50 * that handles this structure only uses additions.
51 *****************************************************************************/
52 typedef struct aout_increment_s
54 /* The remainder is used to keep track of the fractional part of the
59 * The increment structure is initialized with the result of an euclidean
62 * l_euclidean_numerator l_euclidean_remainder
63 * ----------------------- = l_euclidean_integer + -----------------------
64 * l_euclidean_denominator l_euclidean_denominator
67 long l_euclidean_integer;
68 long l_euclidean_remainder;
69 long l_euclidean_denominator;
73 /*****************************************************************************
75 *****************************************************************************/
76 typedef struct aout_fifo_s
78 /* See the fifo types below */
81 int i_fifo; /* Just to keep track of the fifo index */
87 vlc_mutex_t data_lock;
93 /* The start frame is the first frame in the buffer that contains decoded
94 * audio data. It it also the first frame in the current timestamped frame
95 * area, ie the first dated frame in the decoded part of the buffer. :-p */
97 boolean_t b_start_frame;
98 /* The next frame is the end frame of the current timestamped frame area,
99 * ie the first dated frame after the start frame. */
101 boolean_t b_next_frame;
102 /* The end frame is the first frame, after the start frame, that doesn't
103 * contain decoded audio data. That's why the end frame is the first frame
104 * where the audio decoder can store its decoded audio frames. */
108 aout_increment_t unit_increment;
109 /* The following variable is used to store the number of remaining audio
110 * units in the current timestamped frame area. */
115 #define AOUT_EMPTY_FIFO 0
116 #define AOUT_INTF_MONO_FIFO 1
117 #define AOUT_INTF_STEREO_FIFO 2
118 #define AOUT_ADEC_MONO_FIFO 3
119 #define AOUT_ADEC_STEREO_FIFO 4
121 /*****************************************************************************
122 * aout_thread_t : audio output thread descriptor
123 *****************************************************************************/
124 typedef int (aout_open_t) ( p_aout_thread_t p_aout );
125 typedef int (aout_setformat_t) ( p_aout_thread_t p_aout );
126 typedef long (aout_getbufinfo_t) ( p_aout_thread_t p_aout,
127 long l_buffer_limit );
128 typedef void (aout_play_t) ( p_aout_thread_t p_aout,
129 byte_t *buffer, int i_size );
130 typedef void (aout_close_t) ( p_aout_thread_t p_aout );
132 typedef struct aout_thread_s
134 vlc_thread_t thread_id;
138 vlc_mutex_t fifos_lock;
139 aout_fifo_t fifo[ AOUT_MAX_FIFOS ];
141 /* Plugin used and shortcuts to access its capabilities */
142 struct module_s * p_module;
143 aout_open_t * pf_open;
144 aout_setformat_t * pf_setformat;
145 aout_getbufinfo_t * pf_getbufinfo;
146 aout_play_t * pf_play;
147 aout_close_t * pf_close;
150 /* The s32 buffer is used to mix all the audio fifos together before
151 * converting them and storing them in the audio output buffer */
154 /* The size of the audio output buffer is kept in audio units, as this is
155 * the only unit that is common with every audio decoder and audio fifo */
159 /* date is the moment where the first audio unit of the output buffer
163 /* Path to the audio output device (default is set to "/dev/dsp") */
167 /* Format of the audio output samples */
169 /* Number of channels */
171 /* Mono or Stereo sound */
173 /* Rate and gain of the audio output sound (in Hz) */
177 /* there might be some useful private structure, such as audio_buf_info
178 * for the OSS output */
182 /* there is the current volume */
187 /* Those are from <linux/soundcard.h> but are needed because of formats
188 * on other platforms */
189 #define AOUT_FMT_U8 0x00000008
190 #define AOUT_FMT_S16_LE 0x00000010 /* Little endian signed 16 */
191 #define AOUT_FMT_S16_BE 0x00000020 /* Big endian signed 16 */
192 #define AOUT_FMT_S8 0x00000040
193 #define AOUT_FMT_U16_LE 0x00000080 /* Little endian U16 */
194 #define AOUT_FMT_U16_BE 0x00000100 /* Big endian U16 */
196 #ifdef WORDS_BIGENDIAN
197 #define AOUT_FMT_S16_NE AOUT_FMT_S16_BE
199 #define AOUT_FMT_S16_NE AOUT_FMT_S16_LE
202 /*****************************************************************************
204 *****************************************************************************/
205 aout_thread_t * aout_CreateThread ( int *pi_status );
206 void aout_DestroyThread ( aout_thread_t *p_aout,
209 aout_fifo_t * aout_CreateFifo ( aout_thread_t *p_aout,
210 aout_fifo_t *p_fifo );
211 void aout_DestroyFifo ( aout_fifo_t *p_fifo );
212 void aout_FreeFifo ( aout_fifo_t *p_fifo );