audio_output.h 8.58 KB
Newer Older
1
/*****************************************************************************
Michel Kaempf's avatar
Michel Kaempf committed
2
 * audio_output.h : audio output thread interface
3
 *****************************************************************************
4 5 6
 * Copyright (C) 1999, 2000 VideoLAN
 *
 * Authors:
7
 * Michel Kaempf <maxx@via.ecp.fr>
8 9 10 11 12
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
13
 * 
14 15
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
16 17
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
18
 *
19 20 21
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111, USA.
22 23 24
 *****************************************************************************/

/*****************************************************************************
Michel Kaempf's avatar
Michel Kaempf committed
25 26 27
 * Required headers:
 * - "common.h"                                                   ( boolean_t )
 * - "mtime.h"                                                      ( mtime_t )
28
 * - "threads.h"                                               ( vlc_thread_t )
29
 *****************************************************************************/
Michel Kaempf's avatar
Michel Kaempf committed
30 31 32 33 34 35 36 37 38 39 40 41 42 43 44

/* TODO :
 *
 * - Créer un flag destroy dans les fifos audio pour indiquer au thread audio
 *   qu'il peut libérer la mémoire occupée par le buffer de la fifo lorsqu'il
 *   le désire (fin du son ou fin du thread)
 *
 */

/*
 * Macros
 */
#define AOUT_FIFO_ISEMPTY( fifo )       ( (fifo).l_end_frame == (fifo).i_start_frame )
#define AOUT_FIFO_ISFULL( fifo )        ( ((((fifo).l_end_frame + 1) - (fifo).l_start_frame) & AOUT_FIFO_SIZE) == 0 )

45
/*****************************************************************************
Michel Kaempf's avatar
Michel Kaempf committed
46
 * aout_increment_t
47
 *****************************************************************************
Michel Kaempf's avatar
Michel Kaempf committed
48 49 50
 * This structure is used to keep the progression of an index up-to-date, in
 * order to avoid rounding problems and heavy computations, as the function
 * that handles this structure only uses additions.
51
 *****************************************************************************/
Michel Kaempf's avatar
Michel Kaempf committed
52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72
typedef struct
{
    /* The remainder is used to keep track of the fractional part of the
     * index. */
    long                l_remainder;

    /*
     * The increment structure is initialized with the result of an euclidean
     * division :
     *
     *  l_euclidean_numerator                           l_euclidean_remainder
     * ----------------------- = l_euclidean_integer + -----------------------
     * l_euclidean_denominator                         l_euclidean_denominator
     *
     */
    long                l_euclidean_integer;
    long                l_euclidean_remainder;
    long                l_euclidean_denominator;

} aout_increment_t;

73
/*****************************************************************************
Michel Kaempf's avatar
Michel Kaempf committed
74
 * aout_fifo_t
75
 *****************************************************************************/
Michel Kaempf's avatar
Michel Kaempf committed
76 77 78 79 80 81
typedef struct
{
    /* See the fifo types below */
    int                 i_type;
    boolean_t           b_die;

82
    int                 i_channels;
83
    boolean_t           b_stereo;
Michel Kaempf's avatar
Michel Kaempf committed
84 85
    long                l_rate;

86 87
    vlc_mutex_t         data_lock;
    vlc_cond_t          data_wait;
Michel Kaempf's avatar
Michel Kaempf committed
88

Michel Kaempf's avatar
Michel Kaempf committed
89
    long                l_frame_size;
Michel Kaempf's avatar
Michel Kaempf committed
90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119
    void *              buffer;
    mtime_t *           date;
    /* The start frame is the first frame in the buffer that contains decoded
     * audio data. It it also the first frame in the current timestamped frame
     * area, ie the first dated frame in the decoded part of the buffer. :-p */
    long                l_start_frame;
    boolean_t           b_start_frame;
    /* The next frame is the end frame of the current timestamped frame area,
     * ie the first dated frame after the start frame. */
    long                l_next_frame;
    boolean_t           b_next_frame;
    /* The end frame is the first frame, after the start frame, that doesn't
     * contain decoded audio data. That's why the end frame is the first frame
     * where the audio decoder can store its decoded audio frames. */
    long                l_end_frame;

    long                l_unit;
    aout_increment_t    unit_increment;
    /* The following variable is used to store the number of remaining audio
     * units in the current timestamped frame area. */
    long                l_units;

} aout_fifo_t;

#define AOUT_EMPTY_FIFO         0
#define AOUT_INTF_MONO_FIFO     1
#define AOUT_INTF_STEREO_FIFO   2
#define AOUT_ADEC_MONO_FIFO     3
#define AOUT_ADEC_STEREO_FIFO   4

120
/*****************************************************************************
121
 * aout_thread_t : audio output thread descriptor
122
 *****************************************************************************/
123 124 125 126 127
typedef int  (aout_sys_open_t)           ( p_aout_thread_t p_aout );
typedef int  (aout_sys_reset_t)          ( p_aout_thread_t p_aout );
typedef int  (aout_sys_setformat_t)      ( p_aout_thread_t p_aout );
typedef int  (aout_sys_setchannels_t)    ( p_aout_thread_t p_aout );
typedef int  (aout_sys_setrate_t)        ( p_aout_thread_t p_aout );
128 129
typedef long (aout_sys_getbufinfo_t)     ( p_aout_thread_t p_aout,
                                           long l_buffer_limit );
130
typedef void (aout_sys_playsamples_t)    ( p_aout_thread_t p_aout,
131
                                           byte_t *buffer, int i_size );
132
typedef void (aout_sys_close_t)          ( p_aout_thread_t p_aout );
133

Michel Kaempf's avatar
Michel Kaempf committed
134 135
typedef struct aout_thread_s
{
136
    vlc_thread_t        thread_id;
Michel Kaempf's avatar
Michel Kaempf committed
137
    boolean_t           b_die;
Sam Hocevar's avatar
Sam Hocevar committed
138
    boolean_t           b_active;
Michel Kaempf's avatar
Michel Kaempf committed
139

140
    vlc_mutex_t         fifos_lock;
Michel Kaempf's avatar
Michel Kaempf committed
141 142
    aout_fifo_t         fifo[ AOUT_MAX_FIFOS ];

143
    /* Plugins */
144 145 146 147 148 149 150 151 152
    aout_sys_open_t *           p_sys_open;
    aout_sys_reset_t *          p_sys_reset;
    aout_sys_setformat_t *      p_sys_setformat;
    aout_sys_setchannels_t *    p_sys_setchannels;
    aout_sys_setrate_t *        p_sys_setrate;
    aout_sys_getbufinfo_t *     p_sys_getbufinfo;
    aout_sys_playsamples_t *    p_sys_playsamples;
    aout_sys_close_t *          p_sys_close;

Michel Kaempf's avatar
Michel Kaempf committed
153 154 155 156 157 158 159 160
    void *              buffer;
    /* The s32 buffer is used to mix all the audio fifos together before
     * converting them and storing them in the audio output buffer */
    s32 *               s32_buffer;

    /* The size of the audio output buffer is kept in audio units, as this is
     * the only unit that is common with every audio decoder and audio fifo */
    long                l_units;
Michel Kaempf's avatar
Michel Kaempf committed
161
    long                l_msleep;
Michel Kaempf's avatar
Michel Kaempf committed
162 163

    /* date is the moment where the first audio unit of the output buffer
Michel Kaempf's avatar
Michel Kaempf committed
164 165
     * will be played */
    mtime_t             date;
Michel Kaempf's avatar
Michel Kaempf committed
166

167 168 169 170 171 172 173 174
    /* Path to the audio output device (default is set to "/dev/dsp") */
    char *              psz_device;
    int                 i_fd;

    /* Format of the audio output samples */
    int                 i_format;
    /* Number of channels */
    int                 i_channels;
175 176
    /* Mono or Stereo sound */
    boolean_t           b_stereo;
177 178 179 180 181 182 183 184
    /* Rate and gain of the audio output sound (in Hz) */
    long                l_rate;
    long                l_gain;

    /* there might be some useful private structure, such as audio_buf_info
     * for the OSS output */
    p_aout_sys_t        p_sys;

Renaud Dartus's avatar
 
Renaud Dartus committed
185 186 187 188

    /* there is the current volume */
    int                 vol;

Michel Kaempf's avatar
Michel Kaempf committed
189 190
} aout_thread_t;

191 192 193 194 195 196 197 198 199 200 201 202 203 204 205
/* Those are from <linux/soundcard.h> but are needed because of formats
 * on other platforms */
#define AOUT_FMT_U8          0x00000008
#define AOUT_FMT_S16_LE      0x00000010           /* Little endian signed 16 */
#define AOUT_FMT_S16_BE      0x00000020              /* Big endian signed 16 */
#define AOUT_FMT_S8          0x00000040
#define AOUT_FMT_U16_LE      0x00000080                 /* Little endian U16 */
#define AOUT_FMT_U16_BE      0x00000100                    /* Big endian U16 */

#if __BYTE_ORDER == __LITTLE_ENDIAN
#define AOUT_FMT_S16_NE      AOUT_FMT_S16_LE
#elif __BYTE_ORDER == __BIG_ENDIAN
#define AOUT_FMT_S16_NE      AOUT_FMT_S16_BE
#endif

206
/*****************************************************************************
Michel Kaempf's avatar
Michel Kaempf committed
207
 * Prototypes
208
 *****************************************************************************/
Vincent Seguin's avatar
Vincent Seguin committed
209 210 211
aout_thread_t * aout_CreateThread       ( int *pi_status );
void            aout_DestroyThread      ( aout_thread_t *p_aout, int *pi_status );

Michel Kaempf's avatar
Michel Kaempf committed
212 213 214

aout_fifo_t *   aout_CreateFifo         ( aout_thread_t *p_aout, aout_fifo_t *p_fifo );
void            aout_DestroyFifo        ( aout_fifo_t *p_fifo );