1 /*****************************************************************************
2 * mixer.c : audio output mixing operations
3 *****************************************************************************
4 * Copyright (C) 2002 VideoLAN
5 * $Id: mixer.c,v 1.23 2003/01/06 22:07:47 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 int aout_MixerDelete( aout_instance_t * p_aout )
63 if ( p_aout->mixer.b_error ) return 0;
64 module_Unneed( p_aout, p_aout->mixer.p_module );
65 p_aout->mixer.b_error = 1;
70 /*****************************************************************************
71 * MixBuffer: try to prepare one output buffer
72 *****************************************************************************
73 * Please note that you must hold the mixer lock.
74 *****************************************************************************/
75 static int MixBuffer( aout_instance_t * p_aout )
77 int i, i_first_input = 0;
78 aout_buffer_t * p_output_buffer;
79 mtime_t start_date, end_date;
80 audio_date_t exact_start_date;
82 if ( p_aout->mixer.b_error )
84 /* Free all incoming buffers. */
85 vlc_mutex_lock( &p_aout->input_fifos_lock );
86 for ( i = 0; i < p_aout->i_nb_inputs; i++ )
88 aout_input_t * p_input = p_aout->pp_inputs[i];
89 aout_buffer_t * p_buffer = p_input->fifo.p_first;
90 if ( p_input->b_error ) continue;
91 while ( p_buffer != NULL )
93 aout_buffer_t * p_next = p_buffer->p_next;
94 aout_BufferFree( p_buffer );
98 vlc_mutex_unlock( &p_aout->input_fifos_lock );
103 vlc_mutex_lock( &p_aout->output_fifo_lock );
104 vlc_mutex_lock( &p_aout->input_fifos_lock );
106 /* Retrieve the date of the next buffer. */
107 memcpy( &exact_start_date, &p_aout->output.fifo.end_date,
108 sizeof(audio_date_t) );
109 start_date = aout_DateGet( &exact_start_date );
111 if ( start_date != 0 && start_date < mdate() )
113 /* The output is _very_ late. This can only happen if the user
114 * pauses the stream (or if the decoder is buggy, which cannot
116 msg_Warn( p_aout, "output PTS is out of range ("I64Fd"), clearing out",
117 mdate() - start_date );
118 aout_FifoSet( p_aout, &p_aout->output.fifo, 0 );
119 aout_DateSet( &exact_start_date, 0 );
123 vlc_mutex_unlock( &p_aout->output_fifo_lock );
125 /* See if we have enough data to prepare a new buffer for the audio
126 * output. First : start date. */
129 /* Find the latest start date available. */
130 for ( i = 0; i < p_aout->i_nb_inputs; i++ )
132 aout_input_t * p_input = p_aout->pp_inputs[i];
133 aout_fifo_t * p_fifo = &p_input->fifo;
134 aout_buffer_t * p_buffer;
136 if ( p_input->b_error ) continue;
138 p_buffer = p_fifo->p_first;
139 while ( p_buffer != NULL && p_buffer->start_date < mdate() )
141 msg_Warn( p_aout, "input PTS is out of range ("I64Fd"), "
142 "trashing", mdate() - p_buffer->start_date );
143 p_buffer = aout_FifoPop( p_aout, p_fifo );
144 aout_BufferFree( p_buffer );
145 p_buffer = p_fifo->p_first;
148 if ( p_buffer == NULL )
153 if ( !start_date || start_date < p_buffer->start_date )
155 aout_DateSet( &exact_start_date, p_buffer->start_date );
156 start_date = p_buffer->start_date;
160 if ( i < p_aout->i_nb_inputs )
162 /* Interrupted before the end... We can't run. */
163 vlc_mutex_unlock( &p_aout->input_fifos_lock );
167 aout_DateIncrement( &exact_start_date, p_aout->output.i_nb_samples );
168 end_date = aout_DateGet( &exact_start_date );
170 /* Check that start_date and end_date are available for all input
172 for ( i = 0; i < p_aout->i_nb_inputs; i++ )
174 aout_input_t * p_input = p_aout->pp_inputs[i];
175 aout_fifo_t * p_fifo = &p_input->fifo;
176 aout_buffer_t * p_buffer;
178 vlc_bool_t b_drop_buffers;
180 if ( p_input->b_error )
182 if ( i_first_input == i ) i_first_input++;
186 p_buffer = p_fifo->p_first;
187 if ( p_buffer == NULL )
192 /* Check for the continuity of start_date */
193 while ( p_buffer != NULL && p_buffer->end_date < start_date )
195 aout_buffer_t * p_next = p_buffer->p_next;
196 msg_Warn( p_aout, "the mixer got a packet in the past ("I64Fd")",
197 start_date - p_buffer->end_date );
198 aout_BufferFree( p_buffer );
199 p_fifo->p_first = p_buffer = p_next;
200 p_input->p_first_byte_to_mix = NULL;
202 if ( p_buffer == NULL )
204 p_fifo->pp_last = &p_fifo->p_first;
208 if ( !AOUT_FMT_NON_LINEAR( &p_aout->mixer.mixer ) )
210 /* Additionally check that p_first_byte_to_mix is well
212 mtime_t i_nb_bytes = (start_date - p_buffer->start_date)
213 * p_aout->mixer.mixer.i_bytes_per_frame
214 * p_aout->mixer.mixer.i_rate
215 / p_aout->mixer.mixer.i_frame_length
217 ptrdiff_t mixer_nb_bytes;
219 if ( p_input->p_first_byte_to_mix == NULL )
221 p_input->p_first_byte_to_mix = p_buffer->p_buffer;
223 mixer_nb_bytes = p_input->p_first_byte_to_mix
224 - p_buffer->p_buffer;
226 if ( !((i_nb_bytes + p_aout->mixer.mixer.i_bytes_per_frame
228 (i_nb_bytes < p_aout->mixer.mixer.i_bytes_per_frame
232 "mixer start isn't output start ("I64Fd,
233 i_nb_bytes - mixer_nb_bytes );
235 /* Round to the nearest multiple */
236 i_nb_bytes /= p_aout->mixer.mixer.i_bytes_per_frame;
237 i_nb_bytes *= p_aout->mixer.mixer.i_bytes_per_frame;
238 p_input->p_first_byte_to_mix = p_buffer->p_buffer
243 /* Check that we have enough samples. */
246 p_buffer = p_fifo->p_first;
247 if ( p_buffer == NULL ) break;
248 if ( p_buffer->end_date >= end_date ) break;
250 /* Check that all buffers are contiguous. */
251 prev_date = p_fifo->p_first->end_date;
252 p_buffer = p_buffer->p_next;
254 for ( ; p_buffer != NULL; p_buffer = p_buffer->p_next )
256 if ( prev_date != p_buffer->start_date )
259 "buffer hole, dropping packets ("I64Fd")",
260 p_buffer->start_date - prev_date );
264 if ( p_buffer->end_date >= end_date ) break;
265 prev_date = p_buffer->end_date;
267 if ( b_drop_buffers )
269 aout_buffer_t * p_deleted = p_fifo->p_first;
270 while ( p_deleted != NULL && p_deleted != p_buffer )
272 aout_buffer_t * p_next = p_deleted->p_next;
273 aout_BufferFree( p_deleted );
276 p_fifo->p_first = p_deleted; /* == p_buffer */
280 if ( p_buffer == NULL ) break;
283 if ( i < p_aout->i_nb_inputs || i_first_input == p_aout->i_nb_inputs )
285 /* Interrupted before the end... We can't run. */
286 vlc_mutex_unlock( &p_aout->input_fifos_lock );
291 aout_BufferAlloc( &p_aout->mixer.output_alloc,
292 ((uint64_t)p_aout->output.i_nb_samples * 1000000)
293 / p_aout->output.output.i_rate,
294 /* This is a bit kludgy, but is actually only used
295 * for the S/PDIF dummy mixer : */
296 p_aout->pp_inputs[i_first_input]->fifo.p_first,
298 if ( p_output_buffer == NULL )
300 msg_Err( p_aout, "out of memory" );
301 vlc_mutex_unlock( &p_aout->input_fifos_lock );
304 /* This is again a bit kludgy - for the S/PDIF mixer. */
305 if ( p_aout->mixer.output_alloc.i_alloc_type != AOUT_ALLOC_NONE )
307 p_output_buffer->i_nb_samples = p_aout->output.i_nb_samples;
308 p_output_buffer->i_nb_bytes = p_aout->output.i_nb_samples
309 * p_aout->mixer.mixer.i_bytes_per_frame
310 / p_aout->mixer.mixer.i_frame_length;
312 p_output_buffer->start_date = start_date;
313 p_output_buffer->end_date = end_date;
315 p_aout->mixer.pf_do_work( p_aout, p_output_buffer );
317 vlc_mutex_unlock( &p_aout->input_fifos_lock );
319 aout_OutputPlay( p_aout, p_output_buffer );
324 /*****************************************************************************
325 * aout_MixerRun: entry point for the mixer & post-filters processing
326 *****************************************************************************
327 * Please note that you must hold the mixer lock.
328 *****************************************************************************/
329 void aout_MixerRun( aout_instance_t * p_aout )
331 while( MixBuffer( p_aout ) != -1 );
334 /*****************************************************************************
335 * aout_MixerMultiplierSet: set p_aout->mixer.f_multiplier
336 *****************************************************************************
337 * Please note that we assume that you own the mixer lock when entering this
338 * function. This function returns -1 on error.
339 *****************************************************************************/
340 int aout_MixerMultiplierSet( aout_instance_t * p_aout, float f_multiplier )
342 float f_old = p_aout->mixer.f_multiplier;
343 vlc_bool_t b_new_mixer = 0;
345 if ( !p_aout->mixer.b_error )
347 aout_MixerDelete( p_aout );
351 p_aout->mixer.f_multiplier = f_multiplier;
353 if ( b_new_mixer && aout_MixerNew( p_aout ) )
355 p_aout->mixer.f_multiplier = f_old;
356 aout_MixerNew( p_aout );
363 /*****************************************************************************
364 * aout_MixerMultiplierGet: get p_aout->mixer.f_multiplier
365 *****************************************************************************
366 * Please note that we assume that you own the mixer lock when entering this
367 * function. This function returns -1 on error.
368 *****************************************************************************/
369 int aout_MixerMultiplierGet( aout_instance_t * p_aout, float * pf_multiplier )
371 *pf_multiplier = p_aout->mixer.f_multiplier;