1 /*****************************************************************************
2 * common.c : audio output management of common data structures
3 *****************************************************************************
4 * Copyright (C) 2002-2007 the VideoLAN team
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., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301, USA.
22 *****************************************************************************/
24 /*****************************************************************************
26 *****************************************************************************/
33 #include <vlc_common.h>
35 #include "aout_internal.h"
39 * Instances management (internal and external)
42 #define AOUT_ASSERT_FIFO_LOCKED aout_assert_fifo_locked(p_aout, p_fifo)
43 static inline void aout_assert_fifo_locked( aout_instance_t * p_aout, aout_fifo_t * p_fifo )
49 if( p_fifo == &p_aout->output.fifo )
50 vlc_assert_locked( &p_aout->output_fifo_lock );
54 for( i = 0; i < p_aout->i_nb_inputs; i++ )
56 if( p_fifo == &p_aout->pp_inputs[i]->mixer.fifo)
58 vlc_assert_locked( &p_aout->input_fifos_lock );
62 if( i == p_aout->i_nb_inputs )
63 vlc_assert_locked( &p_aout->mixer_lock );
72 static void aout_Destructor( vlc_object_t * p_this );
74 /*****************************************************************************
75 * aout_New: initialize aout structure
76 *****************************************************************************/
77 aout_instance_t * __aout_New( vlc_object_t * p_parent )
79 aout_instance_t * p_aout;
81 /* Allocate descriptor. */
82 p_aout = vlc_object_create( p_parent, VLC_OBJECT_AOUT );
88 /* Initialize members. */
89 vlc_mutex_init( &p_aout->input_fifos_lock );
90 vlc_mutex_init( &p_aout->mixer_lock );
91 vlc_mutex_init( &p_aout->output_fifo_lock );
92 p_aout->i_nb_inputs = 0;
93 p_aout->mixer_multiplier = 1.0;
94 p_aout->p_mixer = NULL;
95 p_aout->output.b_error = 1;
96 p_aout->output.b_starving = 1;
98 var_Create( p_aout, "intf-change", VLC_VAR_BOOL );
99 var_SetBool( p_aout, "intf-change", true );
101 vlc_object_set_destructor( p_aout, aout_Destructor );
106 /*****************************************************************************
107 * aout_Destructor: destroy aout structure
108 *****************************************************************************/
109 static void aout_Destructor( vlc_object_t * p_this )
111 aout_instance_t * p_aout = (aout_instance_t *)p_this;
112 vlc_mutex_destroy( &p_aout->input_fifos_lock );
113 vlc_mutex_destroy( &p_aout->mixer_lock );
114 vlc_mutex_destroy( &p_aout->output_fifo_lock );
117 /* Lock ordering rules:
119 * Mixer Input IFIFO OFIFO (< Inner lock)
120 * Mixer No! N/A Yes Yes
121 * Input N/A No! Yes N/A
122 * In FIFOs No! No! No! Yes
123 * Out FIFOs No! N/A No! No!
128 static __thread unsigned aout_locks = 0;
130 void aout_lock (unsigned i)
141 case INPUT_FIFO_LOCK:
142 allowed = MIXER_LOCK|INPUT_LOCK;
144 case OUTPUT_FIFO_LOCK:
145 allowed = MIXER_LOCK|INPUT_FIFO_LOCK;
149 if (aout_locks & ~allowed)
151 fprintf (stderr, "Illegal audio lock transition (%x -> %x)\n",
152 aout_locks, aout_locks|i);
159 void aout_unlock (unsigned i)
161 assert (aout_locks & i);
167 * Formats management (internal and external)
170 /*****************************************************************************
171 * aout_FormatNbChannels : return the number of channels
172 *****************************************************************************/
173 unsigned int aout_FormatNbChannels( const audio_sample_format_t * p_format )
175 static const uint32_t pi_channels[] =
176 { AOUT_CHAN_CENTER, AOUT_CHAN_LEFT, AOUT_CHAN_RIGHT,
177 AOUT_CHAN_REARCENTER, AOUT_CHAN_REARLEFT, AOUT_CHAN_REARRIGHT,
178 AOUT_CHAN_MIDDLELEFT, AOUT_CHAN_MIDDLERIGHT, AOUT_CHAN_LFE };
179 unsigned int i_nb = 0, i;
181 for ( i = 0; i < sizeof(pi_channels)/sizeof(uint32_t); i++ )
183 if ( p_format->i_physical_channels & pi_channels[i] ) i_nb++;
189 /*****************************************************************************
190 * aout_BitsPerSample : get the number of bits per sample
191 *****************************************************************************/
192 unsigned int aout_BitsPerSample( vlc_fourcc_t i_format )
222 /* For these formats the caller has to indicate the parameters
228 /*****************************************************************************
229 * aout_FormatPrepare : compute the number of bytes per frame & frame length
230 *****************************************************************************/
231 void aout_FormatPrepare( audio_sample_format_t * p_format )
233 p_format->i_bitspersample = aout_BitsPerSample( p_format->i_format );
234 if( p_format->i_bitspersample > 0 )
236 p_format->i_bytes_per_frame = ( p_format->i_bitspersample / 8 )
237 * aout_FormatNbChannels( p_format );
238 p_format->i_frame_length = 1;
242 /*****************************************************************************
243 * aout_FormatPrintChannels : print a channel in a human-readable form
244 *****************************************************************************/
245 const char * aout_FormatPrintChannels( const audio_sample_format_t * p_format )
247 switch ( p_format->i_physical_channels & AOUT_CHAN_PHYSMASK )
250 case AOUT_CHAN_RIGHT:
251 case AOUT_CHAN_CENTER:
252 if ( (p_format->i_original_channels & AOUT_CHAN_CENTER)
253 || (p_format->i_original_channels
254 & (AOUT_CHAN_LEFT | AOUT_CHAN_RIGHT)) )
256 else if ( p_format->i_original_channels & AOUT_CHAN_LEFT )
259 case AOUT_CHAN_LEFT | AOUT_CHAN_RIGHT:
260 if ( p_format->i_original_channels & AOUT_CHAN_REVERSESTEREO )
262 if ( p_format->i_original_channels & AOUT_CHAN_DOLBYSTEREO )
263 return "Dolby/Reverse";
264 return "Stereo/Reverse";
268 if ( p_format->i_original_channels & AOUT_CHAN_DOLBYSTEREO )
270 else if ( p_format->i_original_channels & AOUT_CHAN_DUALMONO )
272 else if ( p_format->i_original_channels == AOUT_CHAN_CENTER )
273 return "Stereo/Mono";
274 else if ( !(p_format->i_original_channels & AOUT_CHAN_RIGHT) )
275 return "Stereo/Left";
276 else if ( !(p_format->i_original_channels & AOUT_CHAN_LEFT) )
277 return "Stereo/Right";
280 case AOUT_CHAN_LEFT | AOUT_CHAN_RIGHT | AOUT_CHAN_CENTER:
282 case AOUT_CHAN_LEFT | AOUT_CHAN_RIGHT | AOUT_CHAN_REARCENTER:
284 case AOUT_CHAN_LEFT | AOUT_CHAN_RIGHT | AOUT_CHAN_CENTER
285 | AOUT_CHAN_REARCENTER:
287 case AOUT_CHAN_LEFT | AOUT_CHAN_RIGHT
288 | AOUT_CHAN_REARLEFT | AOUT_CHAN_REARRIGHT:
290 case AOUT_CHAN_LEFT | AOUT_CHAN_RIGHT
291 | AOUT_CHAN_MIDDLELEFT | AOUT_CHAN_MIDDLERIGHT:
293 case AOUT_CHAN_LEFT | AOUT_CHAN_RIGHT | AOUT_CHAN_CENTER
294 | AOUT_CHAN_REARLEFT | AOUT_CHAN_REARRIGHT:
296 case AOUT_CHAN_LEFT | AOUT_CHAN_RIGHT | AOUT_CHAN_CENTER
297 | AOUT_CHAN_MIDDLELEFT | AOUT_CHAN_MIDDLERIGHT:
300 case AOUT_CHAN_CENTER | AOUT_CHAN_LFE:
301 if ( (p_format->i_original_channels & AOUT_CHAN_CENTER)
302 || (p_format->i_original_channels
303 & (AOUT_CHAN_LEFT | AOUT_CHAN_RIGHT)) )
305 else if ( p_format->i_original_channels & AOUT_CHAN_LEFT )
308 case AOUT_CHAN_LEFT | AOUT_CHAN_RIGHT | AOUT_CHAN_LFE:
309 if ( p_format->i_original_channels & AOUT_CHAN_DOLBYSTEREO )
311 else if ( p_format->i_original_channels & AOUT_CHAN_DUALMONO )
312 return "Dual-mono/LFE";
313 else if ( p_format->i_original_channels == AOUT_CHAN_CENTER )
315 else if ( !(p_format->i_original_channels & AOUT_CHAN_RIGHT) )
316 return "Stereo/Left/LFE";
317 else if ( !(p_format->i_original_channels & AOUT_CHAN_LEFT) )
318 return "Stereo/Right/LFE";
320 case AOUT_CHAN_LEFT | AOUT_CHAN_RIGHT | AOUT_CHAN_CENTER | AOUT_CHAN_LFE:
322 case AOUT_CHAN_LEFT | AOUT_CHAN_RIGHT | AOUT_CHAN_REARCENTER
325 case AOUT_CHAN_LEFT | AOUT_CHAN_RIGHT | AOUT_CHAN_CENTER
326 | AOUT_CHAN_REARCENTER | AOUT_CHAN_LFE:
328 case AOUT_CHAN_LEFT | AOUT_CHAN_RIGHT
329 | AOUT_CHAN_REARLEFT | AOUT_CHAN_REARRIGHT | AOUT_CHAN_LFE:
331 case AOUT_CHAN_LEFT | AOUT_CHAN_RIGHT
332 | AOUT_CHAN_MIDDLELEFT | AOUT_CHAN_MIDDLERIGHT | AOUT_CHAN_LFE:
334 case AOUT_CHAN_LEFT | AOUT_CHAN_RIGHT | AOUT_CHAN_CENTER
335 | AOUT_CHAN_REARLEFT | AOUT_CHAN_REARRIGHT | AOUT_CHAN_LFE:
337 case AOUT_CHAN_LEFT | AOUT_CHAN_RIGHT | AOUT_CHAN_CENTER
338 | AOUT_CHAN_MIDDLELEFT | AOUT_CHAN_MIDDLERIGHT | AOUT_CHAN_LFE:
340 case AOUT_CHAN_LEFT | AOUT_CHAN_RIGHT | AOUT_CHAN_CENTER
341 | AOUT_CHAN_REARLEFT | AOUT_CHAN_REARRIGHT | AOUT_CHAN_MIDDLELEFT
342 | AOUT_CHAN_MIDDLERIGHT:
344 case AOUT_CHAN_LEFT | AOUT_CHAN_RIGHT | AOUT_CHAN_CENTER
345 | AOUT_CHAN_REARLEFT | AOUT_CHAN_REARRIGHT | AOUT_CHAN_MIDDLELEFT
346 | AOUT_CHAN_MIDDLERIGHT | AOUT_CHAN_LFE:
353 /*****************************************************************************
354 * aout_FormatPrint : print a format in a human-readable form
355 *****************************************************************************/
356 void aout_FormatPrint( aout_instance_t * p_aout, const char * psz_text,
357 const audio_sample_format_t * p_format )
359 msg_Dbg( p_aout, "%s '%4.4s' %d Hz %s frame=%d samples/%d bytes", psz_text,
360 (char *)&p_format->i_format, p_format->i_rate,
361 aout_FormatPrintChannels( p_format ),
362 p_format->i_frame_length, p_format->i_bytes_per_frame );
365 /*****************************************************************************
366 * aout_FormatsPrint : print two formats in a human-readable form
367 *****************************************************************************/
368 void aout_FormatsPrint( aout_instance_t * p_aout, const char * psz_text,
369 const audio_sample_format_t * p_format1,
370 const audio_sample_format_t * p_format2 )
372 msg_Dbg( p_aout, "%s '%4.4s'->'%4.4s' %d Hz->%d Hz %s->%s",
374 (char *)&p_format1->i_format, (char *)&p_format2->i_format,
375 p_format1->i_rate, p_format2->i_rate,
376 aout_FormatPrintChannels( p_format1 ),
377 aout_FormatPrintChannels( p_format2 ) );
382 * FIFO management (internal) - please understand that solving race conditions
383 * is _your_ job, ie. in the audio output you should own the mixer lock
384 * before calling any of these functions.
387 /*****************************************************************************
388 * aout_FifoInit : initialize the members of a FIFO
389 *****************************************************************************/
390 void aout_FifoInit( aout_instance_t * p_aout, aout_fifo_t * p_fifo,
393 AOUT_ASSERT_FIFO_LOCKED;
397 msg_Err( p_aout, "initialising fifo with zero divider" );
400 p_fifo->p_first = NULL;
401 p_fifo->pp_last = &p_fifo->p_first;
402 date_Init( &p_fifo->end_date, i_rate, 1 );
405 /*****************************************************************************
406 * aout_FifoPush : push a packet into the FIFO
407 *****************************************************************************/
408 void aout_FifoPush( aout_instance_t * p_aout, aout_fifo_t * p_fifo,
409 aout_buffer_t * p_buffer )
412 AOUT_ASSERT_FIFO_LOCKED;
414 *p_fifo->pp_last = p_buffer;
415 p_fifo->pp_last = &p_buffer->p_next;
416 *p_fifo->pp_last = NULL;
417 /* Enforce the continuity of the stream. */
418 if ( date_Get( &p_fifo->end_date ) )
420 p_buffer->i_pts = date_Get( &p_fifo->end_date );
421 p_buffer->i_length = date_Increment( &p_fifo->end_date,
422 p_buffer->i_nb_samples );
423 p_buffer->i_length -= p_buffer->i_pts;
427 date_Set( &p_fifo->end_date, p_buffer->i_pts + p_buffer->i_length );
431 /*****************************************************************************
432 * aout_FifoSet : set end_date and trash all buffers (because they aren't
434 *****************************************************************************/
435 void aout_FifoSet( aout_instance_t * p_aout, aout_fifo_t * p_fifo,
438 aout_buffer_t * p_buffer;
440 AOUT_ASSERT_FIFO_LOCKED;
442 date_Set( &p_fifo->end_date, date );
443 p_buffer = p_fifo->p_first;
444 while ( p_buffer != NULL )
446 aout_buffer_t * p_next = p_buffer->p_next;
447 aout_BufferFree( p_buffer );
450 p_fifo->p_first = NULL;
451 p_fifo->pp_last = &p_fifo->p_first;
454 /*****************************************************************************
455 * aout_FifoMoveDates : Move forwards or backwards all dates in the FIFO
456 *****************************************************************************/
457 void aout_FifoMoveDates( aout_instance_t * p_aout, aout_fifo_t * p_fifo,
460 aout_buffer_t * p_buffer;
462 AOUT_ASSERT_FIFO_LOCKED;
464 date_Move( &p_fifo->end_date, difference );
465 p_buffer = p_fifo->p_first;
466 while ( p_buffer != NULL )
468 p_buffer->i_pts += difference;
469 p_buffer = p_buffer->p_next;
473 /*****************************************************************************
474 * aout_FifoNextStart : return the current end_date
475 *****************************************************************************/
476 mtime_t aout_FifoNextStart( aout_instance_t * p_aout, aout_fifo_t * p_fifo )
479 AOUT_ASSERT_FIFO_LOCKED;
480 return date_Get( &p_fifo->end_date );
483 /*****************************************************************************
484 * aout_FifoFirstDate : return the playing date of the first buffer in the
486 *****************************************************************************/
487 mtime_t aout_FifoFirstDate( aout_instance_t * p_aout, aout_fifo_t * p_fifo )
490 AOUT_ASSERT_FIFO_LOCKED;
491 return p_fifo->p_first ? p_fifo->p_first->i_pts : 0;
494 /*****************************************************************************
495 * aout_FifoPop : get the next buffer out of the FIFO
496 *****************************************************************************/
497 aout_buffer_t * aout_FifoPop( aout_instance_t * p_aout, aout_fifo_t * p_fifo )
499 aout_buffer_t * p_buffer;
501 AOUT_ASSERT_FIFO_LOCKED;
503 p_buffer = p_fifo->p_first;
504 if ( p_buffer == NULL ) return NULL;
505 p_fifo->p_first = p_buffer->p_next;
506 if ( p_fifo->p_first == NULL )
508 p_fifo->pp_last = &p_fifo->p_first;
514 /*****************************************************************************
515 * aout_FifoDestroy : destroy a FIFO and its buffers
516 *****************************************************************************/
517 void aout_FifoDestroy( aout_instance_t * p_aout, aout_fifo_t * p_fifo )
519 aout_buffer_t * p_buffer;
521 AOUT_ASSERT_FIFO_LOCKED;
523 p_buffer = p_fifo->p_first;
524 while ( p_buffer != NULL )
526 aout_buffer_t * p_next = p_buffer->p_next;
527 aout_BufferFree( p_buffer );
531 p_fifo->p_first = NULL;
532 p_fifo->pp_last = &p_fifo->p_first;
535 /*****************************************************************************
536 * aout_CheckChannelReorder : Check if we need to do some channel re-ordering
537 *****************************************************************************/
538 int aout_CheckChannelReorder( const uint32_t *pi_chan_order_in,
539 const uint32_t *pi_chan_order_out,
540 uint32_t i_channel_mask,
541 int i_channels, int *pi_chan_table )
543 bool b_chan_reorder = false;
546 if( i_channels > AOUT_CHAN_MAX )
549 if( pi_chan_order_in == NULL )
550 pi_chan_order_in = pi_vlc_chan_order_wg4;
551 if( pi_chan_order_out == NULL )
552 pi_chan_order_out = pi_vlc_chan_order_wg4;
554 for( i = 0, j = 0; pi_chan_order_in[i]; i++ )
556 if( !(i_channel_mask & pi_chan_order_in[i]) ) continue;
558 for( k = 0, l = 0; pi_chan_order_in[i] != pi_chan_order_out[k]; k++ )
560 if( i_channel_mask & pi_chan_order_out[k] ) l++;
563 pi_chan_table[j++] = l;
566 for( i = 0; i < i_channels; i++ )
568 if( pi_chan_table[i] != i ) b_chan_reorder = true;
571 return b_chan_reorder;
574 /*****************************************************************************
575 * aout_ChannelReorder :
576 *****************************************************************************/
577 void aout_ChannelReorder( uint8_t *p_buf, int i_buffer,
578 int i_channels, const int *pi_chan_table,
579 int i_bits_per_sample )
581 uint8_t p_tmp[AOUT_CHAN_MAX * 4];
584 if( i_bits_per_sample == 8 )
586 for( i = 0; i < i_buffer / i_channels; i++ )
588 for( j = 0; j < i_channels; j++ )
590 p_tmp[pi_chan_table[j]] = p_buf[j];
593 memcpy( p_buf, p_tmp, i_channels );
597 else if( i_bits_per_sample == 16 )
599 for( i = 0; i < i_buffer / i_channels / 2; i++ )
601 for( j = 0; j < i_channels; j++ )
603 p_tmp[2 * pi_chan_table[j]] = p_buf[2 * j];
604 p_tmp[2 * pi_chan_table[j] + 1] = p_buf[2 * j + 1];
607 memcpy( p_buf, p_tmp, 2 * i_channels );
608 p_buf += 2 * i_channels;
611 else if( i_bits_per_sample == 24 )
613 for( i = 0; i < i_buffer / i_channels / 3; i++ )
615 for( j = 0; j < i_channels; j++ )
617 p_tmp[3 * pi_chan_table[j]] = p_buf[3 * j];
618 p_tmp[3 * pi_chan_table[j] + 1] = p_buf[3 * j + 1];
619 p_tmp[3 * pi_chan_table[j] + 2] = p_buf[3 * j + 2];
622 memcpy( p_buf, p_tmp, 3 * i_channels );
623 p_buf += 3 * i_channels;
626 else if( i_bits_per_sample == 32 )
628 for( i = 0; i < i_buffer / i_channels / 4; i++ )
630 for( j = 0; j < i_channels; j++ )
632 p_tmp[4 * pi_chan_table[j]] = p_buf[4 * j];
633 p_tmp[4 * pi_chan_table[j] + 1] = p_buf[4 * j + 1];
634 p_tmp[4 * pi_chan_table[j] + 2] = p_buf[4 * j + 2];
635 p_tmp[4 * pi_chan_table[j] + 3] = p_buf[4 * j + 3];
638 memcpy( p_buf, p_tmp, 4 * i_channels );
639 p_buf += 4 * i_channels;
644 /*****************************************************************************
645 * aout_ChannelExtract:
646 *****************************************************************************/
647 static inline void ExtractChannel( uint8_t *pi_dst, int i_dst_channels,
648 const uint8_t *pi_src, int i_src_channels,
650 const int *pi_selection, int i_bytes )
652 for( int i = 0; i < i_sample_count; i++ )
654 for( int j = 0; j < i_dst_channels; j++ )
655 memcpy( &pi_dst[j * i_bytes], &pi_src[pi_selection[j] * i_bytes], i_bytes );
656 pi_dst += i_dst_channels * i_bytes;
657 pi_src += i_src_channels * i_bytes;
661 void aout_ChannelExtract( void *p_dst, int i_dst_channels,
662 const void *p_src, int i_src_channels,
663 int i_sample_count, const int *pi_selection, int i_bits_per_sample )
665 /* It does not work in place */
666 assert( p_dst != p_src );
668 /* Force the compiler to inline for the specific cases so it can optimize */
669 if( i_bits_per_sample == 8 )
670 ExtractChannel( p_dst, i_dst_channels, p_src, i_src_channels, i_sample_count, pi_selection, 1 );
671 else if( i_bits_per_sample == 16 )
672 ExtractChannel( p_dst, i_dst_channels, p_src, i_src_channels, i_sample_count, pi_selection, 2 );
673 else if( i_bits_per_sample == 24 )
674 ExtractChannel( p_dst, i_dst_channels, p_src, i_src_channels, i_sample_count, pi_selection, 3 );
675 else if( i_bits_per_sample == 32 )
676 ExtractChannel( p_dst, i_dst_channels, p_src, i_src_channels, i_sample_count, pi_selection, 4 );
677 else if( i_bits_per_sample == 64 )
678 ExtractChannel( p_dst, i_dst_channels, p_src, i_src_channels, i_sample_count, pi_selection, 8 );
681 bool aout_CheckChannelExtraction( int *pi_selection,
682 uint32_t *pi_layout, int *pi_channels,
683 const uint32_t pi_order_dst[AOUT_CHAN_MAX],
684 const uint32_t *pi_order_src, int i_channels )
686 const uint32_t pi_order_dual_mono[] = { AOUT_CHAN_LEFT, AOUT_CHAN_RIGHT };
687 uint32_t i_layout = 0;
689 int pi_index[AOUT_CHAN_MAX];
693 pi_order_dst = pi_vlc_chan_order_wg4;
695 /* Detect special dual mono case */
696 if( i_channels == 2 &&
697 pi_order_src[0] == AOUT_CHAN_CENTER && pi_order_src[1] == AOUT_CHAN_CENTER )
699 i_layout |= AOUT_CHAN_DUALMONO;
700 pi_order_src = pi_order_dual_mono;
704 for( int i = 0; i < i_channels; i++ )
706 /* Ignore unknown or duplicated channels or not present in output */
707 if( !pi_order_src[i] || (i_layout & pi_order_src[i]) )
710 for( int j = 0; j < AOUT_CHAN_MAX; j++ )
712 if( pi_order_dst[j] == pi_order_src[i] )
714 assert( i_out < AOUT_CHAN_MAX );
715 pi_index[i_out++] = i;
716 i_layout |= pi_order_src[i];
723 for( int i = 0, j = 0; i < AOUT_CHAN_MAX; i++ )
725 for( int k = 0; k < i_out; k++ )
727 if( pi_order_dst[i] == pi_order_src[pi_index[k]] )
729 pi_selection[j++] = pi_index[k];
735 *pi_layout = i_layout;
736 *pi_channels = i_out;
738 for( int i = 0; i < i_out; i++ )
740 if( pi_selection[i] != i )
743 return i_out == i_channels;
746 /*****************************************************************************
748 *****************************************************************************/
750 aout_buffer_t *aout_BufferAlloc(aout_alloc_t *allocation, mtime_t microseconds,
751 aout_buffer_t *old_buffer)
753 if ( !allocation->b_alloc )
758 size_t i_alloc_size = (int)( (uint64_t)allocation->i_bytes_per_sec
759 * (microseconds) / 1000000 + 1 );
761 return block_Alloc( i_alloc_size );