1 /*****************************************************************************
2 * mixer.c : audio output mixing operations
3 *****************************************************************************
4 * Copyright (C) 2002 VideoLAN
5 * $Id: mixer.c,v 1.28 2003/11/24 21:47:33 gbazin 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() */
36 #include "audio_output.h"
37 #include "aout_internal.h"
39 /*****************************************************************************
40 * aout_MixerNew: prepare a mixer plug-in
41 *****************************************************************************
42 * Please note that you must hold the mixer lock.
43 *****************************************************************************/
44 int aout_MixerNew( aout_instance_t * p_aout )
46 p_aout->mixer.p_module = module_Need( p_aout, "audio mixer", NULL );
47 if ( p_aout->mixer.p_module == NULL )
49 msg_Err( p_aout, "no suitable aout mixer" );
52 p_aout->mixer.b_error = 0;
56 /*****************************************************************************
57 * aout_MixerDelete: delete the mixer
58 *****************************************************************************
59 * Please note that you must hold the mixer lock.
60 *****************************************************************************/
61 void aout_MixerDelete( aout_instance_t * p_aout )
63 if ( p_aout->mixer.b_error ) return;
64 module_Unneed( p_aout, p_aout->mixer.p_module );
65 p_aout->mixer.b_error = 1;
68 /*****************************************************************************
69 * MixBuffer: try to prepare one output buffer
70 *****************************************************************************
71 * Please note that you must hold the mixer lock.
72 *****************************************************************************/
73 static int MixBuffer( aout_instance_t * p_aout )
75 int i, i_first_input = 0;
76 aout_buffer_t * p_output_buffer;
77 mtime_t start_date, end_date;
78 audio_date_t exact_start_date;
80 if ( p_aout->mixer.b_error )
82 /* Free all incoming buffers. */
83 vlc_mutex_lock( &p_aout->input_fifos_lock );
84 for ( i = 0; i < p_aout->i_nb_inputs; i++ )
86 aout_input_t * p_input = p_aout->pp_inputs[i];
87 aout_buffer_t * p_buffer = p_input->fifo.p_first;
88 if ( p_input->b_error ) continue;
89 while ( p_buffer != NULL )
91 aout_buffer_t * p_next = p_buffer->p_next;
92 aout_BufferFree( p_buffer );
96 vlc_mutex_unlock( &p_aout->input_fifos_lock );
101 vlc_mutex_lock( &p_aout->output_fifo_lock );
102 vlc_mutex_lock( &p_aout->input_fifos_lock );
104 /* Retrieve the date of the next buffer. */
105 memcpy( &exact_start_date, &p_aout->output.fifo.end_date,
106 sizeof(audio_date_t) );
107 start_date = aout_DateGet( &exact_start_date );
109 if ( start_date != 0 && start_date < mdate() )
111 /* The output is _very_ late. This can only happen if the user
112 * pauses the stream (or if the decoder is buggy, which cannot
114 msg_Warn( p_aout, "output PTS is out of range ("I64Fd"), clearing out",
115 mdate() - start_date );
116 aout_FifoSet( p_aout, &p_aout->output.fifo, 0 );
117 aout_DateSet( &exact_start_date, 0 );
121 vlc_mutex_unlock( &p_aout->output_fifo_lock );
123 /* See if we have enough data to prepare a new buffer for the audio
124 * output. First : start date. */
127 /* Find the latest start date available. */
128 for ( i = 0; i < p_aout->i_nb_inputs; i++ )
130 aout_input_t * p_input = p_aout->pp_inputs[i];
131 aout_fifo_t * p_fifo = &p_input->fifo;
132 aout_buffer_t * p_buffer;
134 if ( p_input->b_error ) continue;
136 p_buffer = p_fifo->p_first;
137 while ( p_buffer != NULL && p_buffer->start_date < mdate() )
139 msg_Warn( p_aout, "input PTS is out of range ("I64Fd"), "
140 "trashing", mdate() - p_buffer->start_date );
141 p_buffer = aout_FifoPop( p_aout, p_fifo );
142 aout_BufferFree( p_buffer );
143 p_buffer = p_fifo->p_first;
144 p_input->p_first_byte_to_mix = NULL;
147 if ( p_buffer == NULL )
152 if ( !start_date || start_date < p_buffer->start_date )
154 aout_DateSet( &exact_start_date, p_buffer->start_date );
155 start_date = p_buffer->start_date;
159 if ( i < p_aout->i_nb_inputs )
161 /* Interrupted before the end... We can't run. */
162 vlc_mutex_unlock( &p_aout->input_fifos_lock );
166 aout_DateIncrement( &exact_start_date, p_aout->output.i_nb_samples );
167 end_date = aout_DateGet( &exact_start_date );
169 /* Check that start_date and end_date are available for all input
171 for ( i = 0; i < p_aout->i_nb_inputs; i++ )
173 aout_input_t * p_input = p_aout->pp_inputs[i];
174 aout_fifo_t * p_fifo = &p_input->fifo;
175 aout_buffer_t * p_buffer;
177 vlc_bool_t b_drop_buffers;
179 if ( p_input->b_error )
181 if ( i_first_input == i ) i_first_input++;
185 p_buffer = p_fifo->p_first;
186 if ( p_buffer == NULL )
191 /* Check for the continuity of start_date */
192 while ( p_buffer != NULL && p_buffer->end_date < start_date - 1 )
194 /* We authorize a +-1 because rounding errors get compensated
196 aout_buffer_t * p_next = p_buffer->p_next;
197 msg_Warn( p_aout, "the mixer got a packet in the past ("I64Fd")",
198 start_date - p_buffer->end_date );
199 aout_BufferFree( p_buffer );
200 p_fifo->p_first = p_buffer = p_next;
201 p_input->p_first_byte_to_mix = NULL;
203 if ( p_buffer == NULL )
205 p_fifo->pp_last = &p_fifo->p_first;
209 /* Check that we have enough samples. */
212 p_buffer = p_fifo->p_first;
213 if ( p_buffer == NULL ) break;
214 if ( p_buffer->end_date >= end_date ) break;
216 /* Check that all buffers are contiguous. */
217 prev_date = p_fifo->p_first->end_date;
218 p_buffer = p_buffer->p_next;
220 for ( ; p_buffer != NULL; p_buffer = p_buffer->p_next )
222 if ( prev_date != p_buffer->start_date )
225 "buffer hole, dropping packets ("I64Fd")",
226 p_buffer->start_date - prev_date );
230 if ( p_buffer->end_date >= end_date ) break;
231 prev_date = p_buffer->end_date;
233 if ( b_drop_buffers )
235 aout_buffer_t * p_deleted = p_fifo->p_first;
236 while ( p_deleted != NULL && p_deleted != p_buffer )
238 aout_buffer_t * p_next = p_deleted->p_next;
239 aout_BufferFree( p_deleted );
242 p_fifo->p_first = p_deleted; /* == p_buffer */
246 if ( p_buffer == NULL ) break;
248 p_buffer = p_fifo->p_first;
249 if ( !AOUT_FMT_NON_LINEAR( &p_aout->mixer.mixer ) )
251 /* Additionally check that p_first_byte_to_mix is well
253 mtime_t i_nb_bytes = (start_date - p_buffer->start_date)
254 * p_aout->mixer.mixer.i_bytes_per_frame
255 * p_aout->mixer.mixer.i_rate
256 / p_aout->mixer.mixer.i_frame_length
258 ptrdiff_t mixer_nb_bytes;
260 if ( p_input->p_first_byte_to_mix == NULL )
262 p_input->p_first_byte_to_mix = p_buffer->p_buffer;
264 mixer_nb_bytes = p_input->p_first_byte_to_mix
265 - p_buffer->p_buffer;
267 if ( !((i_nb_bytes + p_aout->mixer.mixer.i_bytes_per_frame
269 (i_nb_bytes < p_aout->mixer.mixer.i_bytes_per_frame
273 "mixer start isn't output start ("I64Fd")",
274 i_nb_bytes - mixer_nb_bytes );
276 /* Round to the nearest multiple */
277 i_nb_bytes /= p_aout->mixer.mixer.i_bytes_per_frame;
278 i_nb_bytes *= p_aout->mixer.mixer.i_bytes_per_frame;
279 p_input->p_first_byte_to_mix = p_buffer->p_buffer
285 if ( i < p_aout->i_nb_inputs || i_first_input == p_aout->i_nb_inputs )
287 /* Interrupted before the end... We can't run. */
288 vlc_mutex_unlock( &p_aout->input_fifos_lock );
293 aout_BufferAlloc( &p_aout->mixer.output_alloc,
294 ((uint64_t)p_aout->output.i_nb_samples * 1000000)
295 / p_aout->output.output.i_rate,
296 /* This is a bit kludgy, but is actually only used
297 * for the S/PDIF dummy mixer : */
298 p_aout->pp_inputs[i_first_input]->fifo.p_first,
300 if ( p_output_buffer == NULL )
302 msg_Err( p_aout, "out of memory" );
303 vlc_mutex_unlock( &p_aout->input_fifos_lock );
306 /* This is again a bit kludgy - for the S/PDIF mixer. */
307 if ( p_aout->mixer.output_alloc.i_alloc_type != AOUT_ALLOC_NONE )
309 p_output_buffer->i_nb_samples = p_aout->output.i_nb_samples;
310 p_output_buffer->i_nb_bytes = p_aout->output.i_nb_samples
311 * p_aout->mixer.mixer.i_bytes_per_frame
312 / p_aout->mixer.mixer.i_frame_length;
314 p_output_buffer->start_date = start_date;
315 p_output_buffer->end_date = end_date;
317 p_aout->mixer.pf_do_work( p_aout, p_output_buffer );
319 vlc_mutex_unlock( &p_aout->input_fifos_lock );
321 aout_OutputPlay( p_aout, p_output_buffer );
326 /*****************************************************************************
327 * aout_MixerRun: entry point for the mixer & post-filters processing
328 *****************************************************************************
329 * Please note that you must hold the mixer lock.
330 *****************************************************************************/
331 void aout_MixerRun( aout_instance_t * p_aout )
333 while( MixBuffer( p_aout ) != -1 );
336 /*****************************************************************************
337 * aout_MixerMultiplierSet: set p_aout->mixer.f_multiplier
338 *****************************************************************************
339 * Please note that we assume that you own the mixer lock when entering this
340 * function. This function returns -1 on error.
341 *****************************************************************************/
342 int aout_MixerMultiplierSet( aout_instance_t * p_aout, float f_multiplier )
344 float f_old = p_aout->mixer.f_multiplier;
345 vlc_bool_t b_new_mixer = 0;
347 if ( !p_aout->mixer.b_error )
349 aout_MixerDelete( p_aout );
353 p_aout->mixer.f_multiplier = f_multiplier;
355 if ( b_new_mixer && aout_MixerNew( p_aout ) )
357 p_aout->mixer.f_multiplier = f_old;
358 aout_MixerNew( p_aout );
365 /*****************************************************************************
366 * aout_MixerMultiplierGet: get p_aout->mixer.f_multiplier
367 *****************************************************************************
368 * Please note that we assume that you own the mixer lock when entering this
369 * function. This function returns -1 on error.
370 *****************************************************************************/
371 int aout_MixerMultiplierGet( aout_instance_t * p_aout, float * pf_multiplier )
373 *pf_multiplier = p_aout->mixer.f_multiplier;