1 /*****************************************************************************
2 * audio_output.h : audio output thread interface
4 *****************************************************************************
6 * - <sys/soundcard.h> ( audio_buf_info )
7 * - "common.h" ( boolean_t )
8 * - "mtime.h" ( mtime_t )
9 * - "vlc_thread.h" ( vlc_thread_t )
10 *****************************************************************************/
14 * - Créer un flag destroy dans les fifos audio pour indiquer au thread audio
15 * qu'il peut libérer la mémoire occupée par le buffer de la fifo lorsqu'il
16 * le désire (fin du son ou fin du thread)
17 * - Redéplacer les #define dans config.h
22 * Defines => "config.h"
25 /* Default output device. You probably should not change this. */
26 #define AOUT_DEFAULT_DEVICE "/dev/dsp"
28 /* Default audio output format (AOUT_FMT_S16_NE = Native Endianess) */
29 #define AOUT_DEFAULT_FORMAT AOUT_FMT_S16_NE
31 /* Default stereo mode (0 stands for mono, 1 for stereo) */
32 #define AOUT_DEFAULT_STEREO 1
34 /* Audio output rate, in Hz */
35 #define AOUT_MIN_RATE 22050 /* ?? */
36 #define AOUT_DEFAULT_RATE 44100
37 #define AOUT_MAX_RATE 48000
39 /* Number of audio output frames contained in an audio output fifo.
40 * (AOUT_FIFO_SIZE + 1) must be a power of 2, in order to optimise the
41 * %(AOUT_FIFO_SIZE + 1) operation with an &AOUT_FIFO_SIZE.
42 * With 511 we have at least 511*384/2/48000=2 seconds of sound */
43 #define AOUT_FIFO_SIZE 511
45 /* Maximum number of audio fifos. The value of AOUT_MAX_FIFOS should be a power
46 * of two, in order to optimize the '/AOUT_MAX_FIFOS' and '*AOUT_MAX_FIFOS'
47 * operations with '>>' and '<<' (gcc changes this at compilation-time) */
48 #define AOUT_MAX_FIFOS 2
50 /* Duration (in microseconds) of an audio output buffer should be :
51 * - short, in order to be able to play a new song very quickly (especially a
52 * song from the interface)
53 * - long, in order to perform the buffer calculations as few as possible */
54 #define AOUT_BUFFER_DURATION 100000
59 #define AOUT_FIFO_ISEMPTY( fifo ) ( (fifo).l_end_frame == (fifo).i_start_frame )
60 #define AOUT_FIFO_ISFULL( fifo ) ( ((((fifo).l_end_frame + 1) - (fifo).l_start_frame) & AOUT_FIFO_SIZE) == 0 )
62 /*****************************************************************************
64 *****************************************************************************
65 * This structure is used to keep the progression of an index up-to-date, in
66 * order to avoid rounding problems and heavy computations, as the function
67 * that handles this structure only uses additions.
68 *****************************************************************************/
71 /* The remainder is used to keep track of the fractional part of the
76 * The increment structure is initialized with the result of an euclidean
79 * l_euclidean_numerator l_euclidean_remainder
80 * ----------------------- = l_euclidean_integer + -----------------------
81 * l_euclidean_denominator l_euclidean_denominator
84 long l_euclidean_integer;
85 long l_euclidean_remainder;
86 long l_euclidean_denominator;
90 /*****************************************************************************
92 *****************************************************************************/
95 /* See the fifo types below */
103 vlc_mutex_t data_lock;
104 vlc_cond_t data_wait;
109 /* The start frame is the first frame in the buffer that contains decoded
110 * audio data. It it also the first frame in the current timestamped frame
111 * area, ie the first dated frame in the decoded part of the buffer. :-p */
113 boolean_t b_start_frame;
114 /* The next frame is the end frame of the current timestamped frame area,
115 * ie the first dated frame after the start frame. */
117 boolean_t b_next_frame;
118 /* The end frame is the first frame, after the start frame, that doesn't
119 * contain decoded audio data. That's why the end frame is the first frame
120 * where the audio decoder can store its decoded audio frames. */
124 aout_increment_t unit_increment;
125 /* The following variable is used to store the number of remaining audio
126 * units in the current timestamped frame area. */
131 #define AOUT_EMPTY_FIFO 0
132 #define AOUT_INTF_MONO_FIFO 1
133 #define AOUT_INTF_STEREO_FIFO 2
134 #define AOUT_ADEC_MONO_FIFO 3
135 #define AOUT_ADEC_STEREO_FIFO 4
137 /*****************************************************************************
138 * aout_thread_t : audio output thread descriptor
139 *****************************************************************************/
140 typedef int (aout_sys_open_t) ( p_aout_thread_t p_aout );
141 typedef int (aout_sys_reset_t) ( p_aout_thread_t p_aout );
142 typedef int (aout_sys_setformat_t) ( p_aout_thread_t p_aout );
143 typedef int (aout_sys_setchannels_t) ( p_aout_thread_t p_aout );
144 typedef int (aout_sys_setrate_t) ( p_aout_thread_t p_aout );
145 typedef long (aout_sys_getbufinfo_t) ( p_aout_thread_t p_aout,
146 long l_buffer_limit );
147 typedef void (aout_sys_playsamples_t) ( p_aout_thread_t p_aout,
148 byte_t *buffer, int i_size );
149 typedef void (aout_sys_close_t) ( p_aout_thread_t p_aout );
151 typedef struct aout_thread_s
153 vlc_thread_t thread_id;
156 vlc_mutex_t fifos_lock;
157 aout_fifo_t fifo[ AOUT_MAX_FIFOS ];
159 /* method-dependant functions */
160 aout_sys_open_t * p_sys_open;
161 aout_sys_reset_t * p_sys_reset;
162 aout_sys_setformat_t * p_sys_setformat;
163 aout_sys_setchannels_t * p_sys_setchannels;
164 aout_sys_setrate_t * p_sys_setrate;
165 aout_sys_getbufinfo_t * p_sys_getbufinfo;
166 aout_sys_playsamples_t * p_sys_playsamples;
167 aout_sys_close_t * p_sys_close;
170 /* The s32 buffer is used to mix all the audio fifos together before
171 * converting them and storing them in the audio output buffer */
174 /* The size of the audio output buffer is kept in audio units, as this is
175 * the only unit that is common with every audio decoder and audio fifo */
179 /* date is the moment where the first audio unit of the output buffer
183 /* Path to the audio output device (default is set to "/dev/dsp") */
187 /* Format of the audio output samples */
189 /* Number of channels */
191 /* Mono or Stereo sound */
193 /* Rate and gain of the audio output sound (in Hz) */
197 /* there might be some useful private structure, such as audio_buf_info
198 * for the OSS output */
204 #define AOUT_DUMMY_METHOD 0x0000 /* dummy video output */
205 #define AOUT_DSP_METHOD 0x0001 /* linux /dev/dsp */
207 /* Get the fallback method */
209 #define AOUT_DEFAULT_METHOD "dsp"
211 #define AOUT_DEFAULT_METHOD "dummy"
214 /* Those are from <linux/soundcard.h> but are needed because of formats
215 * on other platforms */
216 #define AOUT_FMT_U8 0x00000008
217 #define AOUT_FMT_S16_LE 0x00000010 /* Little endian signed 16 */
218 #define AOUT_FMT_S16_BE 0x00000020 /* Big endian signed 16 */
219 #define AOUT_FMT_S8 0x00000040
220 #define AOUT_FMT_U16_LE 0x00000080 /* Little endian U16 */
221 #define AOUT_FMT_U16_BE 0x00000100 /* Big endian U16 */
223 #if __BYTE_ORDER == __LITTLE_ENDIAN
224 #define AOUT_FMT_S16_NE AOUT_FMT_S16_LE
225 #elif __BYTE_ORDER == __BIG_ENDIAN
226 #define AOUT_FMT_S16_NE AOUT_FMT_S16_BE
229 /*****************************************************************************
231 *****************************************************************************/
232 aout_thread_t * aout_CreateThread ( int *pi_status );
233 void aout_DestroyThread ( aout_thread_t *p_aout, int *pi_status );
236 aout_fifo_t * aout_CreateFifo ( aout_thread_t *p_aout, aout_fifo_t *p_fifo );
237 void aout_DestroyFifo ( aout_fifo_t *p_fifo );