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 )
46 if( p_fifo == &p_aout->output.fifo )
47 vlc_assert_locked( &p_aout->output_fifo_lock );
51 for( i = 0; i < p_aout->i_nb_inputs; i++ )
53 if( p_fifo == &p_aout->pp_inputs[i]->fifo)
55 vlc_assert_locked( &p_aout->input_fifos_lock );
59 if( i == p_aout->i_nb_inputs )
60 vlc_assert_locked( &p_aout->mixer_lock );
69 static void aout_Destructor( vlc_object_t * p_this );
71 /*****************************************************************************
72 * aout_New: initialize aout structure
73 *****************************************************************************/
74 aout_instance_t * __aout_New( vlc_object_t * p_parent )
76 aout_instance_t * p_aout;
79 /* Allocate descriptor. */
80 p_aout = vlc_object_create( p_parent, VLC_OBJECT_AOUT );
86 /* Initialize members. */
87 vlc_mutex_init( &p_aout->input_fifos_lock );
88 vlc_mutex_init( &p_aout->mixer_lock );
89 vlc_mutex_init( &p_aout->output_fifo_lock );
90 p_aout->i_nb_inputs = 0;
91 p_aout->mixer.f_multiplier = 1.0;
92 p_aout->mixer.b_error = 1;
93 p_aout->output.b_error = 1;
94 p_aout->output.b_starving = 1;
96 var_Create( p_aout, "intf-change", VLC_VAR_BOOL );
98 var_Set( p_aout, "intf-change", val );
100 vlc_object_set_destructor( p_aout, aout_Destructor );
105 /*****************************************************************************
106 * aout_Destructor: destroy aout structure
107 *****************************************************************************/
108 static void aout_Destructor( vlc_object_t * p_this )
110 aout_instance_t * p_aout = (aout_instance_t *)p_this;
111 vlc_mutex_destroy( &p_aout->input_fifos_lock );
112 vlc_mutex_destroy( &p_aout->mixer_lock );
113 vlc_mutex_destroy( &p_aout->output_fifo_lock );
118 * Formats management (internal and external)
121 /*****************************************************************************
122 * aout_FormatNbChannels : return the number of channels
123 *****************************************************************************/
124 unsigned int aout_FormatNbChannels( const audio_sample_format_t * p_format )
126 static const uint32_t pi_channels[] =
127 { AOUT_CHAN_CENTER, AOUT_CHAN_LEFT, AOUT_CHAN_RIGHT,
128 AOUT_CHAN_REARCENTER, AOUT_CHAN_REARLEFT, AOUT_CHAN_REARRIGHT,
129 AOUT_CHAN_MIDDLELEFT, AOUT_CHAN_MIDDLERIGHT, AOUT_CHAN_LFE };
130 unsigned int i_nb = 0, i;
132 for ( i = 0; i < sizeof(pi_channels)/sizeof(uint32_t); i++ )
134 if ( p_format->i_physical_channels & pi_channels[i] ) i_nb++;
140 /*****************************************************************************
141 * aout_BitsPerSample : get the number of bits per sample
142 *****************************************************************************/
143 unsigned int aout_BitsPerSample( vlc_fourcc_t i_format )
173 /* For these formats the caller has to indicate the parameters
179 /*****************************************************************************
180 * aout_FormatPrepare : compute the number of bytes per frame & frame length
181 *****************************************************************************/
182 void aout_FormatPrepare( audio_sample_format_t * p_format )
184 p_format->i_bitspersample = aout_BitsPerSample( p_format->i_format );
185 if( p_format->i_bitspersample > 0 )
187 p_format->i_bytes_per_frame = ( p_format->i_bitspersample / 8 )
188 * aout_FormatNbChannels( p_format );
189 p_format->i_frame_length = 1;
193 /*****************************************************************************
194 * aout_FormatPrintChannels : print a channel in a human-readable form
195 *****************************************************************************/
196 const char * aout_FormatPrintChannels( const audio_sample_format_t * p_format )
198 switch ( p_format->i_physical_channels & AOUT_CHAN_PHYSMASK )
200 case AOUT_CHAN_CENTER:
201 if ( (p_format->i_original_channels & AOUT_CHAN_CENTER)
202 || (p_format->i_original_channels
203 & (AOUT_CHAN_LEFT | AOUT_CHAN_RIGHT)) )
205 else if ( p_format->i_original_channels & AOUT_CHAN_LEFT )
208 case AOUT_CHAN_LEFT | AOUT_CHAN_RIGHT:
209 if ( p_format->i_original_channels & AOUT_CHAN_REVERSESTEREO )
211 if ( p_format->i_original_channels & AOUT_CHAN_DOLBYSTEREO )
212 return "Dolby/Reverse";
213 return "Stereo/Reverse";
217 if ( p_format->i_original_channels & AOUT_CHAN_DOLBYSTEREO )
219 else if ( p_format->i_original_channels & AOUT_CHAN_DUALMONO )
221 else if ( p_format->i_original_channels == AOUT_CHAN_CENTER )
222 return "Stereo/Mono";
223 else if ( !(p_format->i_original_channels & AOUT_CHAN_RIGHT) )
224 return "Stereo/Left";
225 else if ( !(p_format->i_original_channels & AOUT_CHAN_LEFT) )
226 return "Stereo/Right";
229 case AOUT_CHAN_LEFT | AOUT_CHAN_RIGHT | AOUT_CHAN_CENTER:
231 case AOUT_CHAN_LEFT | AOUT_CHAN_RIGHT | AOUT_CHAN_REARCENTER:
233 case AOUT_CHAN_LEFT | AOUT_CHAN_RIGHT | AOUT_CHAN_CENTER
234 | AOUT_CHAN_REARCENTER:
236 case AOUT_CHAN_LEFT | AOUT_CHAN_RIGHT
237 | AOUT_CHAN_REARLEFT | AOUT_CHAN_REARRIGHT:
239 case AOUT_CHAN_LEFT | AOUT_CHAN_RIGHT
240 | AOUT_CHAN_MIDDLELEFT | AOUT_CHAN_MIDDLERIGHT:
242 case AOUT_CHAN_LEFT | AOUT_CHAN_RIGHT | AOUT_CHAN_CENTER
243 | AOUT_CHAN_REARLEFT | AOUT_CHAN_REARRIGHT:
245 case AOUT_CHAN_LEFT | AOUT_CHAN_RIGHT | AOUT_CHAN_CENTER
246 | AOUT_CHAN_MIDDLELEFT | AOUT_CHAN_MIDDLERIGHT:
249 case AOUT_CHAN_CENTER | AOUT_CHAN_LFE:
250 if ( (p_format->i_original_channels & AOUT_CHAN_CENTER)
251 || (p_format->i_original_channels
252 & (AOUT_CHAN_LEFT | AOUT_CHAN_RIGHT)) )
254 else if ( p_format->i_original_channels & AOUT_CHAN_LEFT )
257 case AOUT_CHAN_LEFT | AOUT_CHAN_RIGHT | AOUT_CHAN_LFE:
258 if ( p_format->i_original_channels & AOUT_CHAN_DOLBYSTEREO )
260 else if ( p_format->i_original_channels & AOUT_CHAN_DUALMONO )
261 return "Dual-mono/LFE";
262 else if ( p_format->i_original_channels == AOUT_CHAN_CENTER )
264 else if ( !(p_format->i_original_channels & AOUT_CHAN_RIGHT) )
265 return "Stereo/Left/LFE";
266 else if ( !(p_format->i_original_channels & AOUT_CHAN_LEFT) )
267 return "Stereo/Right/LFE";
269 case AOUT_CHAN_LEFT | AOUT_CHAN_RIGHT | AOUT_CHAN_CENTER | AOUT_CHAN_LFE:
271 case AOUT_CHAN_LEFT | AOUT_CHAN_RIGHT | AOUT_CHAN_REARCENTER
274 case AOUT_CHAN_LEFT | AOUT_CHAN_RIGHT | AOUT_CHAN_CENTER
275 | AOUT_CHAN_REARCENTER | AOUT_CHAN_LFE:
277 case AOUT_CHAN_LEFT | AOUT_CHAN_RIGHT
278 | AOUT_CHAN_REARLEFT | AOUT_CHAN_REARRIGHT | AOUT_CHAN_LFE:
280 case AOUT_CHAN_LEFT | AOUT_CHAN_RIGHT
281 | AOUT_CHAN_MIDDLELEFT | AOUT_CHAN_MIDDLERIGHT | AOUT_CHAN_LFE:
283 case AOUT_CHAN_LEFT | AOUT_CHAN_RIGHT | AOUT_CHAN_CENTER
284 | AOUT_CHAN_REARLEFT | AOUT_CHAN_REARRIGHT | AOUT_CHAN_LFE:
286 case AOUT_CHAN_LEFT | AOUT_CHAN_RIGHT | AOUT_CHAN_CENTER
287 | AOUT_CHAN_MIDDLELEFT | AOUT_CHAN_MIDDLERIGHT | AOUT_CHAN_LFE:
289 case AOUT_CHAN_LEFT | AOUT_CHAN_RIGHT | AOUT_CHAN_CENTER
290 | AOUT_CHAN_REARLEFT | AOUT_CHAN_REARRIGHT | AOUT_CHAN_MIDDLELEFT
291 | AOUT_CHAN_MIDDLERIGHT:
293 case AOUT_CHAN_LEFT | AOUT_CHAN_RIGHT | AOUT_CHAN_CENTER
294 | AOUT_CHAN_REARLEFT | AOUT_CHAN_REARRIGHT | AOUT_CHAN_MIDDLELEFT
295 | AOUT_CHAN_MIDDLERIGHT | AOUT_CHAN_LFE:
302 /*****************************************************************************
303 * aout_FormatPrint : print a format in a human-readable form
304 *****************************************************************************/
305 void aout_FormatPrint( aout_instance_t * p_aout, const char * psz_text,
306 const audio_sample_format_t * p_format )
308 msg_Dbg( p_aout, "%s '%4.4s' %d Hz %s frame=%d samples/%d bytes", psz_text,
309 (char *)&p_format->i_format, p_format->i_rate,
310 aout_FormatPrintChannels( p_format ),
311 p_format->i_frame_length, p_format->i_bytes_per_frame );
314 /*****************************************************************************
315 * aout_FormatsPrint : print two formats in a human-readable form
316 *****************************************************************************/
317 void aout_FormatsPrint( aout_instance_t * p_aout, const char * psz_text,
318 const audio_sample_format_t * p_format1,
319 const audio_sample_format_t * p_format2 )
321 msg_Dbg( p_aout, "%s '%4.4s'->'%4.4s' %d Hz->%d Hz %s->%s",
323 (char *)&p_format1->i_format, (char *)&p_format2->i_format,
324 p_format1->i_rate, p_format2->i_rate,
325 aout_FormatPrintChannels( p_format1 ),
326 aout_FormatPrintChannels( p_format2 ) );
331 * FIFO management (internal) - please understand that solving race conditions
332 * is _your_ job, ie. in the audio output you should own the mixer lock
333 * before calling any of these functions.
336 /*****************************************************************************
337 * aout_FifoInit : initialize the members of a FIFO
338 *****************************************************************************/
339 void aout_FifoInit( aout_instance_t * p_aout, aout_fifo_t * p_fifo,
342 AOUT_ASSERT_FIFO_LOCKED;
346 msg_Err( p_aout, "initialising fifo with zero divider" );
349 p_fifo->p_first = NULL;
350 p_fifo->pp_last = &p_fifo->p_first;
351 aout_DateInit( &p_fifo->end_date, i_rate );
354 /*****************************************************************************
355 * aout_FifoPush : push a packet into the FIFO
356 *****************************************************************************/
357 void aout_FifoPush( aout_instance_t * p_aout, aout_fifo_t * p_fifo,
358 aout_buffer_t * p_buffer )
361 AOUT_ASSERT_FIFO_LOCKED;
363 *p_fifo->pp_last = p_buffer;
364 p_fifo->pp_last = &p_buffer->p_next;
365 *p_fifo->pp_last = NULL;
366 /* Enforce the continuity of the stream. */
367 if ( aout_DateGet( &p_fifo->end_date ) )
369 p_buffer->start_date = aout_DateGet( &p_fifo->end_date );
370 p_buffer->end_date = aout_DateIncrement( &p_fifo->end_date,
371 p_buffer->i_nb_samples );
375 aout_DateSet( &p_fifo->end_date, p_buffer->end_date );
379 /*****************************************************************************
380 * aout_FifoSet : set end_date and trash all buffers (because they aren't
382 *****************************************************************************/
383 void aout_FifoSet( aout_instance_t * p_aout, aout_fifo_t * p_fifo,
386 aout_buffer_t * p_buffer;
388 AOUT_ASSERT_FIFO_LOCKED;
390 aout_DateSet( &p_fifo->end_date, date );
391 p_buffer = p_fifo->p_first;
392 while ( p_buffer != NULL )
394 aout_buffer_t * p_next = p_buffer->p_next;
395 aout_BufferFree( p_buffer );
398 p_fifo->p_first = NULL;
399 p_fifo->pp_last = &p_fifo->p_first;
402 /*****************************************************************************
403 * aout_FifoMoveDates : Move forwards or backwards all dates in the FIFO
404 *****************************************************************************/
405 void aout_FifoMoveDates( aout_instance_t * p_aout, aout_fifo_t * p_fifo,
408 aout_buffer_t * p_buffer;
410 AOUT_ASSERT_FIFO_LOCKED;
412 aout_DateMove( &p_fifo->end_date, difference );
413 p_buffer = p_fifo->p_first;
414 while ( p_buffer != NULL )
416 p_buffer->start_date += difference;
417 p_buffer->end_date += difference;
418 p_buffer = p_buffer->p_next;
422 /*****************************************************************************
423 * aout_FifoNextStart : return the current end_date
424 *****************************************************************************/
425 mtime_t aout_FifoNextStart( aout_instance_t * p_aout, aout_fifo_t * p_fifo )
428 AOUT_ASSERT_FIFO_LOCKED;
429 return aout_DateGet( &p_fifo->end_date );
432 /*****************************************************************************
433 * aout_FifoFirstDate : return the playing date of the first buffer in the
435 *****************************************************************************/
436 mtime_t aout_FifoFirstDate( aout_instance_t * p_aout, aout_fifo_t * p_fifo )
439 AOUT_ASSERT_FIFO_LOCKED;
440 return p_fifo->p_first ? p_fifo->p_first->start_date : 0;
443 /*****************************************************************************
444 * aout_FifoPop : get the next buffer out of the FIFO
445 *****************************************************************************/
446 aout_buffer_t * aout_FifoPop( aout_instance_t * p_aout, aout_fifo_t * p_fifo )
448 aout_buffer_t * p_buffer;
450 AOUT_ASSERT_FIFO_LOCKED;
452 p_buffer = p_fifo->p_first;
453 if ( p_buffer == NULL ) return NULL;
454 p_fifo->p_first = p_buffer->p_next;
455 if ( p_fifo->p_first == NULL )
457 p_fifo->pp_last = &p_fifo->p_first;
463 /*****************************************************************************
464 * aout_FifoDestroy : destroy a FIFO and its buffers
465 *****************************************************************************/
466 void aout_FifoDestroy( aout_instance_t * p_aout, aout_fifo_t * p_fifo )
468 aout_buffer_t * p_buffer;
470 AOUT_ASSERT_FIFO_LOCKED;
472 p_buffer = p_fifo->p_first;
473 while ( p_buffer != NULL )
475 aout_buffer_t * p_next = p_buffer->p_next;
476 aout_BufferFree( p_buffer );
480 p_fifo->p_first = NULL;
481 p_fifo->pp_last = &p_fifo->p_first;
486 * Date management (internal and external)
489 /*****************************************************************************
490 * aout_DateInit : set the divider of an audio_date_t
491 *****************************************************************************/
492 void aout_DateInit( audio_date_t * p_date, uint32_t i_divider )
495 p_date->i_divider = i_divider;
496 p_date->i_remainder = 0;
499 /*****************************************************************************
500 * aout_DateSet : set the date of an audio_date_t
501 *****************************************************************************/
502 void aout_DateSet( audio_date_t * p_date, mtime_t new_date )
504 p_date->date = new_date;
505 p_date->i_remainder = 0;
508 /*****************************************************************************
509 * aout_DateMove : move forwards or backwards the date of an audio_date_t
510 *****************************************************************************/
511 void aout_DateMove( audio_date_t * p_date, mtime_t difference )
513 p_date->date += difference;
516 /*****************************************************************************
517 * aout_DateGet : get the date of an audio_date_t
518 *****************************************************************************/
519 mtime_t aout_DateGet( const audio_date_t * p_date )
524 /*****************************************************************************
525 * aout_DateIncrement : increment the date and return the result, taking
526 * into account rounding errors
527 *****************************************************************************/
528 mtime_t aout_DateIncrement( audio_date_t * p_date, uint32_t i_nb_samples )
530 mtime_t i_dividend = INT64_C(1000000) * i_nb_samples;
531 assert( p_date->i_divider > 0 ); /* uninitialized audio_data_t ? */
532 p_date->date += i_dividend / p_date->i_divider;
533 p_date->i_remainder += (int)(i_dividend % p_date->i_divider);
534 if ( p_date->i_remainder >= p_date->i_divider )
536 /* This is Bresenham algorithm. */
538 p_date->i_remainder -= p_date->i_divider;
543 /*****************************************************************************
544 * aout_CheckChannelReorder : Check if we need to do some channel re-ordering
545 *****************************************************************************/
546 int aout_CheckChannelReorder( const uint32_t *pi_chan_order_in,
547 const uint32_t *pi_chan_order_out,
548 uint32_t i_channel_mask,
549 int i_channels, int *pi_chan_table )
551 bool b_chan_reorder = false;
554 if( i_channels > AOUT_CHAN_MAX )
557 if( pi_chan_order_in == NULL )
558 pi_chan_order_in = pi_vlc_chan_order_wg4;
559 if( pi_chan_order_out == NULL )
560 pi_chan_order_out = pi_vlc_chan_order_wg4;
562 for( i = 0, j = 0; pi_chan_order_in[i]; i++ )
564 if( !(i_channel_mask & pi_chan_order_in[i]) ) continue;
566 for( k = 0, l = 0; pi_chan_order_in[i] != pi_chan_order_out[k]; k++ )
568 if( i_channel_mask & pi_chan_order_out[k] ) l++;
571 pi_chan_table[j++] = l;
574 for( i = 0; i < i_channels; i++ )
576 if( pi_chan_table[i] != i ) b_chan_reorder = true;
579 return b_chan_reorder;
582 /*****************************************************************************
583 * aout_ChannelReorder :
584 *****************************************************************************/
585 void aout_ChannelReorder( uint8_t *p_buf, int i_buffer,
586 int i_channels, const int *pi_chan_table,
587 int i_bits_per_sample )
589 uint8_t p_tmp[AOUT_CHAN_MAX * 4];
592 if( i_bits_per_sample == 8 )
594 for( i = 0; i < i_buffer / i_channels; i++ )
596 for( j = 0; j < i_channels; j++ )
598 p_tmp[pi_chan_table[j]] = p_buf[j];
601 memcpy( p_buf, p_tmp, i_channels );
605 else if( i_bits_per_sample == 16 )
607 for( i = 0; i < i_buffer / i_channels / 2; i++ )
609 for( j = 0; j < i_channels; j++ )
611 p_tmp[2 * pi_chan_table[j]] = p_buf[2 * j];
612 p_tmp[2 * pi_chan_table[j] + 1] = p_buf[2 * j + 1];
615 memcpy( p_buf, p_tmp, 2 * i_channels );
616 p_buf += 2 * i_channels;
619 else if( i_bits_per_sample == 24 )
621 for( i = 0; i < i_buffer / i_channels / 3; i++ )
623 for( j = 0; j < i_channels; j++ )
625 p_tmp[3 * pi_chan_table[j]] = p_buf[3 * j];
626 p_tmp[3 * pi_chan_table[j] + 1] = p_buf[3 * j + 1];
627 p_tmp[3 * pi_chan_table[j] + 2] = p_buf[3 * j + 2];
630 memcpy( p_buf, p_tmp, 3 * i_channels );
631 p_buf += 3 * i_channels;
634 else if( i_bits_per_sample == 32 )
636 for( i = 0; i < i_buffer / i_channels / 4; i++ )
638 for( j = 0; j < i_channels; j++ )
640 p_tmp[4 * pi_chan_table[j]] = p_buf[4 * j];
641 p_tmp[4 * pi_chan_table[j] + 1] = p_buf[4 * j + 1];
642 p_tmp[4 * pi_chan_table[j] + 2] = p_buf[4 * j + 2];
643 p_tmp[4 * pi_chan_table[j] + 3] = p_buf[4 * j + 3];
646 memcpy( p_buf, p_tmp, 4 * i_channels );
647 p_buf += 4 * i_channels;
652 /*****************************************************************************
653 * aout_ChannelExtract:
654 *****************************************************************************/
655 static inline void ExtractChannel( uint8_t *pi_dst, int i_dst_channels,
656 const uint8_t *pi_src, int i_src_channels,
658 const int *pi_selection, int i_bytes )
660 for( int i = 0; i < i_sample_count; i++ )
662 for( int j = 0; j < i_dst_channels; j++ )
663 memcpy( &pi_dst[j * i_bytes], &pi_src[pi_selection[j] * i_bytes], i_bytes );
664 pi_dst += i_dst_channels * i_bytes;
665 pi_src += i_src_channels * i_bytes;
669 void aout_ChannelExtract( void *p_dst, int i_dst_channels,
670 const void *p_src, int i_src_channels,
671 int i_sample_count, const int *pi_selection, int i_bits_per_sample )
673 /* It does not work in place */
674 assert( p_dst != p_src );
676 /* Force the compiler to inline for the specific cases so it can optimize */
677 if( i_bits_per_sample == 8 )
678 ExtractChannel( p_dst, i_dst_channels, p_src, i_src_channels, i_sample_count, pi_selection, 1 );
679 else if( i_bits_per_sample == 16 )
680 ExtractChannel( p_dst, i_dst_channels, p_src, i_src_channels, i_sample_count, pi_selection, 2 );
681 else if( i_bits_per_sample == 24 )
682 ExtractChannel( p_dst, i_dst_channels, p_src, i_src_channels, i_sample_count, pi_selection, 3 );
683 else if( i_bits_per_sample == 32 )
684 ExtractChannel( p_dst, i_dst_channels, p_src, i_src_channels, i_sample_count, pi_selection, 4 );
685 else if( i_bits_per_sample == 64 )
686 ExtractChannel( p_dst, i_dst_channels, p_src, i_src_channels, i_sample_count, pi_selection, 8 );
689 bool aout_CheckChannelExtraction( int *pi_selection,
690 uint32_t *pi_layout, int *pi_channels,
691 const uint32_t pi_order_dst[AOUT_CHAN_MAX],
692 const uint32_t *pi_order_src, int i_channels )
694 const uint32_t pi_order_dual_mono[] = { AOUT_CHAN_LEFT, AOUT_CHAN_RIGHT };
695 uint32_t i_layout = 0;
697 int pi_index[AOUT_CHAN_MAX];
701 pi_order_dst = pi_vlc_chan_order_wg4;
703 /* Detect special dual mono case */
704 if( i_channels == 2 &&
705 pi_order_src[0] == AOUT_CHAN_CENTER && pi_order_src[1] == AOUT_CHAN_CENTER )
707 i_layout |= AOUT_CHAN_DUALMONO;
708 pi_order_src = pi_order_dual_mono;
712 for( int i = 0; i < i_channels; i++ )
714 /* Ignore unknown or duplicated channels or not present in output */
715 if( !pi_order_src[i] || (i_layout & pi_order_src[i]) )
718 for( int j = 0; j < AOUT_CHAN_MAX; j++ )
720 if( pi_order_dst[j] == pi_order_src[i] )
722 assert( i_out < AOUT_CHAN_MAX );
723 pi_index[i_out++] = i;
724 i_layout |= pi_order_src[i];
731 for( int i = 0, j = 0; i < AOUT_CHAN_MAX; i++ )
733 for( int k = 0; k < i_out; k++ )
735 if( pi_order_dst[i] == pi_order_src[pi_index[k]] )
737 pi_selection[j++] = pi_index[k];
743 *pi_layout = i_layout;
744 *pi_channels = i_out;
746 for( int i = 0; i < i_out; i++ )
748 if( pi_selection[i] != i )
751 return i_out == i_channels;