1 /*****************************************************************************
2 * mixer.c : audio output mixing operations
3 *****************************************************************************
4 * Copyright (C) 2002 VideoLAN
5 * $Id: mixer.c,v 1.24 2003/01/23 17:13:28 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() */
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;
146 if ( p_buffer == NULL )
151 if ( !start_date || start_date < p_buffer->start_date )
153 aout_DateSet( &exact_start_date, p_buffer->start_date );
154 start_date = p_buffer->start_date;
158 if ( i < p_aout->i_nb_inputs )
160 /* Interrupted before the end... We can't run. */
161 vlc_mutex_unlock( &p_aout->input_fifos_lock );
165 aout_DateIncrement( &exact_start_date, p_aout->output.i_nb_samples );
166 end_date = aout_DateGet( &exact_start_date );
168 /* Check that start_date and end_date are available for all input
170 for ( i = 0; i < p_aout->i_nb_inputs; i++ )
172 aout_input_t * p_input = p_aout->pp_inputs[i];
173 aout_fifo_t * p_fifo = &p_input->fifo;
174 aout_buffer_t * p_buffer;
176 vlc_bool_t b_drop_buffers;
178 if ( p_input->b_error )
180 if ( i_first_input == i ) i_first_input++;
184 p_buffer = p_fifo->p_first;
185 if ( p_buffer == NULL )
190 /* Check for the continuity of start_date */
191 while ( p_buffer != NULL && p_buffer->end_date < start_date )
193 aout_buffer_t * p_next = p_buffer->p_next;
194 msg_Warn( p_aout, "the mixer got a packet in the past ("I64Fd")",
195 start_date - p_buffer->end_date );
196 aout_BufferFree( p_buffer );
197 p_fifo->p_first = p_buffer = p_next;
198 p_input->p_first_byte_to_mix = NULL;
200 if ( p_buffer == NULL )
202 p_fifo->pp_last = &p_fifo->p_first;
206 if ( !AOUT_FMT_NON_LINEAR( &p_aout->mixer.mixer ) )
208 /* Additionally check that p_first_byte_to_mix is well
210 mtime_t i_nb_bytes = (start_date - p_buffer->start_date)
211 * p_aout->mixer.mixer.i_bytes_per_frame
212 * p_aout->mixer.mixer.i_rate
213 / p_aout->mixer.mixer.i_frame_length
215 ptrdiff_t mixer_nb_bytes;
217 if ( p_input->p_first_byte_to_mix == NULL )
219 p_input->p_first_byte_to_mix = p_buffer->p_buffer;
221 mixer_nb_bytes = p_input->p_first_byte_to_mix
222 - p_buffer->p_buffer;
224 if ( !((i_nb_bytes + p_aout->mixer.mixer.i_bytes_per_frame
226 (i_nb_bytes < p_aout->mixer.mixer.i_bytes_per_frame
230 "mixer start isn't output start ("I64Fd,
231 i_nb_bytes - mixer_nb_bytes );
233 /* Round to the nearest multiple */
234 i_nb_bytes /= p_aout->mixer.mixer.i_bytes_per_frame;
235 i_nb_bytes *= p_aout->mixer.mixer.i_bytes_per_frame;
236 p_input->p_first_byte_to_mix = p_buffer->p_buffer
241 /* Check that we have enough samples. */
244 p_buffer = p_fifo->p_first;
245 if ( p_buffer == NULL ) break;
246 if ( p_buffer->end_date >= end_date ) break;
248 /* Check that all buffers are contiguous. */
249 prev_date = p_fifo->p_first->end_date;
250 p_buffer = p_buffer->p_next;
252 for ( ; p_buffer != NULL; p_buffer = p_buffer->p_next )
254 if ( prev_date != p_buffer->start_date )
257 "buffer hole, dropping packets ("I64Fd")",
258 p_buffer->start_date - prev_date );
262 if ( p_buffer->end_date >= end_date ) break;
263 prev_date = p_buffer->end_date;
265 if ( b_drop_buffers )
267 aout_buffer_t * p_deleted = p_fifo->p_first;
268 while ( p_deleted != NULL && p_deleted != p_buffer )
270 aout_buffer_t * p_next = p_deleted->p_next;
271 aout_BufferFree( p_deleted );
274 p_fifo->p_first = p_deleted; /* == p_buffer */
278 if ( p_buffer == NULL ) break;
281 if ( i < p_aout->i_nb_inputs || i_first_input == p_aout->i_nb_inputs )
283 /* Interrupted before the end... We can't run. */
284 vlc_mutex_unlock( &p_aout->input_fifos_lock );
289 aout_BufferAlloc( &p_aout->mixer.output_alloc,
290 ((uint64_t)p_aout->output.i_nb_samples * 1000000)
291 / p_aout->output.output.i_rate,
292 /* This is a bit kludgy, but is actually only used
293 * for the S/PDIF dummy mixer : */
294 p_aout->pp_inputs[i_first_input]->fifo.p_first,
296 if ( p_output_buffer == NULL )
298 msg_Err( p_aout, "out of memory" );
299 vlc_mutex_unlock( &p_aout->input_fifos_lock );
302 /* This is again a bit kludgy - for the S/PDIF mixer. */
303 if ( p_aout->mixer.output_alloc.i_alloc_type != AOUT_ALLOC_NONE )
305 p_output_buffer->i_nb_samples = p_aout->output.i_nb_samples;
306 p_output_buffer->i_nb_bytes = p_aout->output.i_nb_samples
307 * p_aout->mixer.mixer.i_bytes_per_frame
308 / p_aout->mixer.mixer.i_frame_length;
310 p_output_buffer->start_date = start_date;
311 p_output_buffer->end_date = end_date;
313 p_aout->mixer.pf_do_work( p_aout, p_output_buffer );
315 vlc_mutex_unlock( &p_aout->input_fifos_lock );
317 aout_OutputPlay( p_aout, p_output_buffer );
322 /*****************************************************************************
323 * aout_MixerRun: entry point for the mixer & post-filters processing
324 *****************************************************************************
325 * Please note that you must hold the mixer lock.
326 *****************************************************************************/
327 void aout_MixerRun( aout_instance_t * p_aout )
329 while( MixBuffer( p_aout ) != -1 );
332 /*****************************************************************************
333 * aout_MixerMultiplierSet: set p_aout->mixer.f_multiplier
334 *****************************************************************************
335 * Please note that we assume that you own the mixer lock when entering this
336 * function. This function returns -1 on error.
337 *****************************************************************************/
338 int aout_MixerMultiplierSet( aout_instance_t * p_aout, float f_multiplier )
340 float f_old = p_aout->mixer.f_multiplier;
341 vlc_bool_t b_new_mixer = 0;
343 if ( !p_aout->mixer.b_error )
345 aout_MixerDelete( p_aout );
349 p_aout->mixer.f_multiplier = f_multiplier;
351 if ( b_new_mixer && aout_MixerNew( p_aout ) )
353 p_aout->mixer.f_multiplier = f_old;
354 aout_MixerNew( p_aout );
361 /*****************************************************************************
362 * aout_MixerMultiplierGet: get p_aout->mixer.f_multiplier
363 *****************************************************************************
364 * Please note that we assume that you own the mixer lock when entering this
365 * function. This function returns -1 on error.
366 *****************************************************************************/
367 int aout_MixerMultiplierGet( aout_instance_t * p_aout, float * pf_multiplier )
369 *pf_multiplier = p_aout->mixer.f_multiplier;