1 /*****************************************************************************
2 * common.c : audio output management of common data structures
3 *****************************************************************************
4 * Copyright (C) 2002 VideoLAN
5 * $Id: common.c,v 1.2 2002/09/30 21:32:33 massiot Exp $
7 * Authors: Christophe Massiot <massiot@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 *****************************************************************************/
27 #include <stdlib.h> /* calloc(), malloc(), free() */
32 #include "audio_output.h"
33 #include "aout_internal.h"
37 * Instances management (internal and external)
40 /*****************************************************************************
41 * aout_New: initialize aout structure
42 *****************************************************************************/
43 aout_instance_t * __aout_New( vlc_object_t * p_parent )
45 aout_instance_t * p_aout;
47 /* Allocate descriptor. */
48 p_aout = vlc_object_create( p_parent, VLC_OBJECT_AOUT );
54 /* Initialize members. */
55 vlc_mutex_init( p_parent, &p_aout->input_fifos_lock );
56 vlc_mutex_init( p_parent, &p_aout->mixer_lock );
57 vlc_mutex_init( p_parent, &p_aout->output_fifo_lock );
58 p_aout->i_nb_inputs = 0;
59 p_aout->mixer.f_multiplier = 1.0;
60 p_aout->mixer.b_error = 1;
62 vlc_object_attach( p_aout, p_parent->p_vlc );
67 /*****************************************************************************
68 * aout_Delete: destroy aout structure
69 *****************************************************************************/
70 void aout_Delete( aout_instance_t * p_aout )
72 vlc_mutex_destroy( &p_aout->input_fifos_lock );
73 vlc_mutex_destroy( &p_aout->mixer_lock );
74 vlc_mutex_destroy( &p_aout->output_fifo_lock );
77 vlc_object_destroy( p_aout );
82 * Formats management (internal and external)
85 /*****************************************************************************
86 * aout_FormatNbChannels : return the number of channels
87 *****************************************************************************/
88 int aout_FormatNbChannels( audio_sample_format_t * p_format )
92 switch ( p_format->i_channels & AOUT_CHAN_MASK )
94 case AOUT_CHAN_CHANNEL1:
95 case AOUT_CHAN_CHANNEL2:
100 case AOUT_CHAN_CHANNEL:
101 case AOUT_CHAN_STEREO:
102 case AOUT_CHAN_DOLBY:
124 if ( p_format->i_channels & AOUT_CHAN_LFE )
130 /*****************************************************************************
131 * aout_FormatPrepare : compute the number of bytes per frame & frame length
132 *****************************************************************************/
133 void aout_FormatPrepare( audio_sample_format_t * p_format )
137 switch ( p_format->i_format )
139 case VLC_FOURCC('u','8',' ',' '):
140 case VLC_FOURCC('s','8',' ',' '):
144 case VLC_FOURCC('u','1','6','l'):
145 case VLC_FOURCC('s','1','6','l'):
146 case VLC_FOURCC('u','1','6','b'):
147 case VLC_FOURCC('s','1','6','b'):
151 case VLC_FOURCC('f','l','3','2'):
152 case VLC_FOURCC('f','i','3','2'):
156 case VLC_FOURCC('s','p','d','i'):
157 case VLC_FOURCC('a','5','2',' '):
158 case VLC_FOURCC('d','t','s',' '):
160 /* For these formats the caller has to indicate the parameters
165 p_format->i_bytes_per_frame = i_result * aout_FormatNbChannels( p_format );
166 p_format->i_frame_length = 1;
171 * FIFO management (internal) - please understand that solving race conditions
172 * is _your_ job, ie. in the audio output you should own the mixer lock
173 * before calling any of these functions.
176 /*****************************************************************************
177 * aout_FifoInit : initialize the members of a FIFO
178 *****************************************************************************/
179 void aout_FifoInit( aout_instance_t * p_aout, aout_fifo_t * p_fifo,
182 p_fifo->p_first = NULL;
183 p_fifo->pp_last = &p_fifo->p_first;
184 aout_DateInit( &p_fifo->end_date, i_rate );
187 /*****************************************************************************
188 * aout_FifoPush : push a packet into the FIFO
189 *****************************************************************************/
190 void aout_FifoPush( aout_instance_t * p_aout, aout_fifo_t * p_fifo,
191 aout_buffer_t * p_buffer )
193 *p_fifo->pp_last = p_buffer;
194 p_fifo->pp_last = &p_buffer->p_next;
195 *p_fifo->pp_last = NULL;
196 /* Enforce the continuity of the stream. */
197 if ( aout_DateGet( &p_fifo->end_date ) )
199 p_buffer->start_date = aout_DateGet( &p_fifo->end_date );
200 p_buffer->end_date = aout_DateIncrement( &p_fifo->end_date,
201 p_buffer->i_nb_samples );
205 aout_DateSet( &p_fifo->end_date, p_buffer->end_date );
209 /*****************************************************************************
210 * aout_FifoSet : set end_date and trash all buffers (because they aren't
212 *****************************************************************************/
213 void aout_FifoSet( aout_instance_t * p_aout, aout_fifo_t * p_fifo,
216 aout_buffer_t * p_buffer;
218 aout_DateSet( &p_fifo->end_date, date );
219 p_buffer = p_fifo->p_first;
220 while ( p_buffer != NULL )
222 aout_buffer_t * p_next = p_buffer->p_next;
223 aout_BufferFree( p_buffer );
226 p_fifo->p_first = NULL;
227 p_fifo->pp_last = &p_fifo->p_first;
230 /*****************************************************************************
231 * aout_FifoMoveDates : Move forwards or backwards all dates in the FIFO
232 *****************************************************************************/
233 void aout_FifoMoveDates( aout_instance_t * p_aout, aout_fifo_t * p_fifo,
236 aout_buffer_t * p_buffer;
238 aout_DateMove( &p_fifo->end_date, difference );
239 p_buffer = p_fifo->p_first;
240 while ( p_buffer != NULL )
242 p_buffer->start_date += difference;
243 p_buffer->end_date += difference;
244 p_buffer = p_buffer->p_next;
248 /*****************************************************************************
249 * aout_FifoNextStart : return the current end_date
250 *****************************************************************************/
251 mtime_t aout_FifoNextStart( aout_instance_t * p_aout, aout_fifo_t * p_fifo )
253 return aout_DateGet( &p_fifo->end_date );
256 /*****************************************************************************
257 * aout_FifoPop : get the next buffer out of the FIFO
258 *****************************************************************************/
259 aout_buffer_t * aout_FifoPop( aout_instance_t * p_aout, aout_fifo_t * p_fifo )
261 aout_buffer_t * p_buffer;
262 p_buffer = p_fifo->p_first;
263 if ( p_buffer == NULL ) return NULL;
264 p_fifo->p_first = p_buffer->p_next;
265 if ( p_fifo->p_first == NULL )
267 p_fifo->pp_last = &p_fifo->p_first;
273 /*****************************************************************************
274 * aout_FifoDestroy : destroy a FIFO and its buffers
275 *****************************************************************************/
276 void aout_FifoDestroy( aout_instance_t * p_aout, aout_fifo_t * p_fifo )
278 aout_buffer_t * p_buffer;
280 p_buffer = p_fifo->p_first;
281 while ( p_buffer != NULL )
283 aout_buffer_t * p_next = p_buffer->p_next;
284 aout_BufferFree( p_buffer );
291 * Date management (internal and external)
294 /*****************************************************************************
295 * aout_DateInit : set the divider of an audio_date_t
296 *****************************************************************************/
297 void aout_DateInit( audio_date_t * p_date, u32 i_divider )
300 p_date->i_divider = i_divider;
301 p_date->i_remainder = 0;
304 /*****************************************************************************
305 * aout_DateSet : set the date of an audio_date_t
306 *****************************************************************************/
307 void aout_DateSet( audio_date_t * p_date, mtime_t new_date )
309 p_date->date = new_date;
310 p_date->i_remainder = 0;
313 /*****************************************************************************
314 * aout_DateMove : move forwards or backwards the date of an audio_date_t
315 *****************************************************************************/
316 void aout_DateMove( audio_date_t * p_date, mtime_t difference )
318 p_date->date += difference;
321 /*****************************************************************************
322 * aout_DateGet : get the date of an audio_date_t
323 *****************************************************************************/
324 mtime_t aout_DateGet( const audio_date_t * p_date )
329 /*****************************************************************************
330 * aout_DateIncrement : increment the date and return the result, taking
331 * into account rounding errors
332 *****************************************************************************/
333 mtime_t aout_DateIncrement( audio_date_t * p_date, u32 i_nb_samples )
335 mtime_t i_dividend = (mtime_t)i_nb_samples * 1000000;
336 p_date->date += i_dividend / p_date->i_divider;
337 p_date->i_remainder += i_dividend % p_date->i_divider;
338 if ( p_date->i_remainder >= p_date->i_divider )
340 /* This is Bresenham algorithm. */
342 p_date->i_remainder -= p_date->i_divider;