1 /*****************************************************************************
2 * headphone.c : headphone virtual spatialization channel mixer module
3 * -> gives the feeling of a real room with a simple headphone
4 *****************************************************************************
5 * Copyright (C) 2002-2006 the VideoLAN team
8 * Authors: Boris Dorès <babal@via.ecp.fr>
10 * This program is free software; you can redistribute it and/or modify
11 * it under the terms of the GNU General Public License as published by
12 * the Free Software Foundation; either version 2 of the License, or
13 * (at your option) any later version.
15 * This program is distributed in the hope that it will be useful,
16 * but WITHOUT ANY WARRANTY; without even the implied warranty of
17 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
18 * GNU General Public License for more details.
20 * You should have received a copy of the GNU General Public License
21 * along with this program; if not, write to the Free Software
22 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301, USA.
23 *****************************************************************************/
25 /*****************************************************************************
27 *****************************************************************************/
33 #include <math.h> /* sqrt */
35 #include <vlc_common.h>
36 #include <vlc_plugin.h>
38 #include <vlc_filter.h>
39 #include <vlc_block.h>
41 /*****************************************************************************
43 *****************************************************************************/
44 static int Create ( vlc_object_t * );
45 static void Destroy ( vlc_object_t * );
47 static void DoWork ( aout_instance_t *, aout_filter_t *, aout_buffer_t *,
51 static int OpenFilter ( vlc_object_t * );
52 static void CloseFilter( vlc_object_t * );
53 static block_t *Convert( filter_t *, block_t * );
55 /*****************************************************************************
57 *****************************************************************************/
58 #define MODULE_DESCRIPTION N_ ( \
59 "This effect gives you the feeling that you are standing in a room " \
60 "with a complete 7.1 speaker set when using only a headphone, " \
61 "providing a more realistic sound experience. It should also be " \
62 "more comfortable and less tiring when listening to music for " \
63 "long periods of time.\nIt works with any source format from mono " \
66 #define HEADPHONE_DIM_TEXT N_("Characteristic dimension")
67 #define HEADPHONE_DIM_LONGTEXT N_( \
68 "Distance between front left speaker and listener in meters.")
70 #define HEADPHONE_COMPENSATE_TEXT N_("Compensate delay")
71 #define HEADPHONE_COMPENSATE_LONGTEXT N_( \
72 "The delay which is introduced by the physical algorithm may "\
73 "sometimes be disturbing for the synchronization between lips-movement "\
74 "and speech. In case, turn this on to compensate.")
76 #define HEADPHONE_DOLBY_TEXT N_("No decoding of Dolby Surround")
77 #define HEADPHONE_DOLBY_LONGTEXT N_( \
78 "Dolby Surround encoded streams won't be decoded before being " \
79 "processed by this filter. Enabling this setting is not recommended.")
82 set_description( N_("Headphone virtual spatialization effect") )
83 set_shortname( N_("Headphone effect") )
84 set_help( MODULE_DESCRIPTION )
85 set_category( CAT_AUDIO )
86 set_subcategory( SUBCAT_AUDIO_AFILTER )
88 add_integer( "headphone-dim", 10, NULL, HEADPHONE_DIM_TEXT,
89 HEADPHONE_DIM_LONGTEXT, false )
90 add_bool( "headphone-compensate", 0, NULL, HEADPHONE_COMPENSATE_TEXT,
91 HEADPHONE_COMPENSATE_LONGTEXT, true )
92 add_bool( "headphone-dolby", 0, NULL, HEADPHONE_DOLBY_TEXT,
93 HEADPHONE_DOLBY_LONGTEXT, true )
95 set_capability( "audio filter", 0 )
96 set_callbacks( Create, Destroy )
97 add_shortcut( "headphone" )
101 set_description( N_("Headphone virtual spatialization effect") )
102 set_capability( "audio filter2", 0 )
103 set_callbacks( OpenFilter, CloseFilter )
107 /*****************************************************************************
108 * Internal data structures
109 *****************************************************************************/
110 struct atomic_operation_t
112 int i_source_channel_offset;
113 int i_dest_channel_offset;
114 unsigned int i_delay;/* in sample unit */
115 double d_amplitude_factor;
118 struct aout_filter_sys_t
120 size_t i_overflow_buffer_size;/* in bytes */
121 uint8_t * p_overflow_buffer;
122 unsigned int i_nb_atomic_operations;
123 struct atomic_operation_t * p_atomic_operations;
128 size_t i_overflow_buffer_size;/* in bytes */
129 uint8_t * p_overflow_buffer;
130 unsigned int i_nb_atomic_operations;
131 struct atomic_operation_t * p_atomic_operations;
134 /*****************************************************************************
135 * Init: initialize internal data structures
136 * and computes the needed atomic operations
137 *****************************************************************************/
138 /* x and z represent the coordinates of the virtual speaker
139 * relatively to the center of the listener's head, measured in meters :
148 * rear left rear right
152 static void ComputeChannelOperations( struct aout_filter_sys_t * p_data
153 , unsigned int i_rate, unsigned int i_next_atomic_operation
154 , int i_source_channel_offset, double d_x, double d_z
155 , double d_compensation_length, double d_channel_amplitude_factor )
157 double d_c = 340; /*sound celerity (unit: m/s)*/
158 double d_compensation_delay = (d_compensation_length-0.1) / d_c * i_rate;
161 p_data->p_atomic_operations[i_next_atomic_operation]
162 .i_source_channel_offset = i_source_channel_offset;
163 p_data->p_atomic_operations[i_next_atomic_operation]
164 .i_dest_channel_offset = 0;/* left */
165 p_data->p_atomic_operations[i_next_atomic_operation]
166 .i_delay = (int)( sqrt( (-0.1-d_x)*(-0.1-d_x) + (0-d_z)*(0-d_z) )
167 / d_c * i_rate - d_compensation_delay );
170 p_data->p_atomic_operations[i_next_atomic_operation]
171 .d_amplitude_factor = d_channel_amplitude_factor * 1.1 / 2;
175 p_data->p_atomic_operations[i_next_atomic_operation]
176 .d_amplitude_factor = d_channel_amplitude_factor * 0.9 / 2;
180 p_data->p_atomic_operations[i_next_atomic_operation]
181 .d_amplitude_factor = d_channel_amplitude_factor / 2;
185 p_data->p_atomic_operations[i_next_atomic_operation + 1]
186 .i_source_channel_offset = i_source_channel_offset;
187 p_data->p_atomic_operations[i_next_atomic_operation + 1]
188 .i_dest_channel_offset = 1;/* right */
189 p_data->p_atomic_operations[i_next_atomic_operation + 1]
190 .i_delay = (int)( sqrt( (0.1-d_x)*(0.1-d_x) + (0-d_z)*(0-d_z) )
191 / d_c * i_rate - d_compensation_delay );
194 p_data->p_atomic_operations[i_next_atomic_operation + 1]
195 .d_amplitude_factor = d_channel_amplitude_factor * 0.9 / 2;
199 p_data->p_atomic_operations[i_next_atomic_operation + 1]
200 .d_amplitude_factor = d_channel_amplitude_factor * 1.1 / 2;
204 p_data->p_atomic_operations[i_next_atomic_operation + 1]
205 .d_amplitude_factor = d_channel_amplitude_factor / 2;
209 static int Init( vlc_object_t *p_this, struct aout_filter_sys_t * p_data
210 , unsigned int i_nb_channels, uint32_t i_physical_channels
211 , unsigned int i_rate )
213 double d_x = config_GetInt( p_this, "headphone-dim" );
215 double d_z_rear = -d_x/3;
217 unsigned int i_next_atomic_operation;
218 int i_source_channel_offset;
221 if( config_GetInt( p_this, "headphone-compensate" ) )
223 /* minimal distance to any speaker */
224 if( i_physical_channels & AOUT_CHAN_REARCENTER )
234 /* Number of elementary operations */
235 p_data->i_nb_atomic_operations = i_nb_channels * 2;
236 if( i_physical_channels & AOUT_CHAN_CENTER )
238 p_data->i_nb_atomic_operations += 2;
240 p_data->p_atomic_operations = malloc( sizeof(struct atomic_operation_t)
241 * p_data->i_nb_atomic_operations );
242 if( p_data->p_atomic_operations == NULL )
245 /* For each virtual speaker, computes elementary wave propagation time
247 i_next_atomic_operation = 0;
248 i_source_channel_offset = 0;
249 if( i_physical_channels & AOUT_CHAN_LEFT )
251 ComputeChannelOperations( p_data , i_rate
252 , i_next_atomic_operation , i_source_channel_offset
253 , -d_x , d_z , d_min , 2.0 / i_nb_channels );
254 i_next_atomic_operation += 2;
255 i_source_channel_offset++;
257 if( i_physical_channels & AOUT_CHAN_RIGHT )
259 ComputeChannelOperations( p_data , i_rate
260 , i_next_atomic_operation , i_source_channel_offset
261 , d_x , d_z , d_min , 2.0 / i_nb_channels );
262 i_next_atomic_operation += 2;
263 i_source_channel_offset++;
265 if( i_physical_channels & AOUT_CHAN_MIDDLELEFT )
267 ComputeChannelOperations( p_data , i_rate
268 , i_next_atomic_operation , i_source_channel_offset
269 , -d_x , 0 , d_min , 1.5 / i_nb_channels );
270 i_next_atomic_operation += 2;
271 i_source_channel_offset++;
273 if( i_physical_channels & AOUT_CHAN_MIDDLERIGHT )
275 ComputeChannelOperations( p_data , i_rate
276 , i_next_atomic_operation , i_source_channel_offset
277 , d_x , 0 , d_min , 1.5 / i_nb_channels );
278 i_next_atomic_operation += 2;
279 i_source_channel_offset++;
281 if( i_physical_channels & AOUT_CHAN_REARLEFT )
283 ComputeChannelOperations( p_data , i_rate
284 , i_next_atomic_operation , i_source_channel_offset
285 , -d_x , d_z_rear , d_min , 1.5 / i_nb_channels );
286 i_next_atomic_operation += 2;
287 i_source_channel_offset++;
289 if( i_physical_channels & AOUT_CHAN_REARRIGHT )
291 ComputeChannelOperations( p_data , i_rate
292 , i_next_atomic_operation , i_source_channel_offset
293 , d_x , d_z_rear , d_min , 1.5 / i_nb_channels );
294 i_next_atomic_operation += 2;
295 i_source_channel_offset++;
297 if( i_physical_channels & AOUT_CHAN_REARCENTER )
299 ComputeChannelOperations( p_data , i_rate
300 , i_next_atomic_operation , i_source_channel_offset
301 , 0 , -d_z , d_min , 1.5 / i_nb_channels );
302 i_next_atomic_operation += 2;
303 i_source_channel_offset++;
305 if( i_physical_channels & AOUT_CHAN_CENTER )
307 /* having two center channels increases the spatialization effect */
308 ComputeChannelOperations( p_data , i_rate
309 , i_next_atomic_operation , i_source_channel_offset
310 , d_x / 5.0 , d_z , d_min , 0.75 / i_nb_channels );
311 i_next_atomic_operation += 2;
312 ComputeChannelOperations( p_data , i_rate
313 , i_next_atomic_operation , i_source_channel_offset
314 , -d_x / 5.0 , d_z , d_min , 0.75 / i_nb_channels );
315 i_next_atomic_operation += 2;
316 i_source_channel_offset++;
318 if( i_physical_channels & AOUT_CHAN_LFE )
320 ComputeChannelOperations( p_data , i_rate
321 , i_next_atomic_operation , i_source_channel_offset
322 , 0 , d_z_rear , d_min , 5.0 / i_nb_channels );
323 i_next_atomic_operation += 2;
324 i_source_channel_offset++;
327 /* Initialize the overflow buffer
328 * we need it because the process induce a delay in the samples */
329 p_data->i_overflow_buffer_size = 0;
330 for( i = 0 ; i < p_data->i_nb_atomic_operations ; i++ )
332 if( p_data->i_overflow_buffer_size
333 < p_data->p_atomic_operations[i].i_delay * 2 * sizeof (float) )
335 p_data->i_overflow_buffer_size
336 = p_data->p_atomic_operations[i].i_delay * 2 * sizeof (float);
339 p_data->p_overflow_buffer = malloc( p_data->i_overflow_buffer_size );
340 if( p_data->p_overflow_buffer == NULL )
342 free( p_data->p_atomic_operations );
345 memset( p_data->p_overflow_buffer, 0 , p_data->i_overflow_buffer_size );
350 /*****************************************************************************
351 * Create: allocate headphone downmixer
352 *****************************************************************************/
353 static int Create( vlc_object_t *p_this )
355 aout_filter_t * p_filter = (aout_filter_t *)p_this;
358 /* Activate this filter only with stereo devices */
359 if( p_filter->output.i_physical_channels
360 != (AOUT_CHAN_LEFT|AOUT_CHAN_RIGHT) )
362 msg_Dbg( p_filter, "filter discarded (incompatible format)" );
366 /* Request a specific format if not already compatible */
367 if( p_filter->input.i_original_channels
368 != p_filter->output.i_original_channels )
371 p_filter->input.i_original_channels =
372 p_filter->output.i_original_channels;
374 if( p_filter->input.i_format != VLC_FOURCC('f','l','3','2')
375 || p_filter->output.i_format != VLC_FOURCC('f','l','3','2') )
378 p_filter->input.i_format = VLC_FOURCC('f','l','3','2');
379 p_filter->output.i_format = VLC_FOURCC('f','l','3','2');
381 if( p_filter->input.i_rate != p_filter->output.i_rate )
384 p_filter->input.i_rate = p_filter->output.i_rate;
386 if( p_filter->input.i_physical_channels == (AOUT_CHAN_LEFT|AOUT_CHAN_RIGHT)
387 && ( p_filter->input.i_original_channels & AOUT_CHAN_DOLBYSTEREO )
388 && ! config_GetInt ( p_filter , "headphone-dolby" ) )
391 p_filter->input.i_physical_channels = AOUT_CHAN_LEFT | AOUT_CHAN_RIGHT |
399 msg_Dbg( p_filter, "requesting specific format" );
403 /* Allocate the memory needed to store the module's structure */
404 p_filter->p_sys = malloc( sizeof(struct aout_filter_sys_t) );
405 if( p_filter->p_sys == NULL )
407 p_filter->p_sys->i_overflow_buffer_size = 0;
408 p_filter->p_sys->p_overflow_buffer = NULL;
409 p_filter->p_sys->i_nb_atomic_operations = 0;
410 p_filter->p_sys->p_atomic_operations = NULL;
412 if( Init( VLC_OBJECT(p_filter), p_filter->p_sys
413 , aout_FormatNbChannels ( &p_filter->input )
414 , p_filter->input.i_physical_channels
415 , p_filter->input.i_rate ) < 0 )
417 free( p_filter->p_sys );
421 p_filter->pf_do_work = DoWork;
422 p_filter->b_in_place = 0;
427 /*****************************************************************************
428 * Destroy: deallocate resources associated with headphone downmixer
429 *****************************************************************************/
430 static void Destroy( vlc_object_t *p_this )
432 aout_filter_t * p_filter = (aout_filter_t *)p_this;
434 if( p_filter->p_sys != NULL )
436 free( p_filter->p_sys->p_overflow_buffer );
437 free( p_filter->p_sys->p_atomic_operations );
438 free( p_filter->p_sys );
439 p_filter->p_sys = NULL;
443 /*****************************************************************************
444 * DoWork: convert a buffer
445 *****************************************************************************/
446 static void DoWork( aout_instance_t * p_aout, aout_filter_t * p_filter,
447 aout_buffer_t * p_in_buf, aout_buffer_t * p_out_buf )
450 int i_input_nb = aout_FormatNbChannels( &p_filter->input );
451 int i_output_nb = aout_FormatNbChannels( &p_filter->output );
453 float * p_in = (float*) p_in_buf->p_buffer;
455 uint8_t * p_overflow;
458 size_t i_overflow_size; /* in bytes */
459 size_t i_out_size; /* in bytes */
463 int i_source_channel_offset;
464 int i_dest_channel_offset;
465 unsigned int i_delay;
466 double d_amplitude_factor;
468 /* out buffer characterisitcs */
469 p_out_buf->i_nb_samples = p_in_buf->i_nb_samples;
470 p_out_buf->i_nb_bytes = p_in_buf->i_nb_bytes * i_output_nb / i_input_nb;
471 p_out = p_out_buf->p_buffer;
472 i_out_size = p_out_buf->i_nb_bytes;
474 if( p_filter->p_sys != NULL )
476 /* Slide the overflow buffer */
477 p_overflow = p_filter->p_sys->p_overflow_buffer;
478 i_overflow_size = p_filter->p_sys->i_overflow_buffer_size;
480 memset( p_out, 0, i_out_size );
481 if ( i_out_size > i_overflow_size )
482 memcpy( p_out, p_overflow, i_overflow_size );
484 memcpy( p_out, p_overflow, i_out_size );
486 p_slide = p_filter->p_sys->p_overflow_buffer;
487 while( p_slide < p_overflow + i_overflow_size )
489 if( p_slide + i_out_size < p_overflow + i_overflow_size )
491 memset( p_slide, 0, i_out_size );
492 if( p_slide + 2 * i_out_size < p_overflow + i_overflow_size )
493 memcpy( p_slide, p_slide + i_out_size, i_out_size );
495 memcpy( p_slide, p_slide + i_out_size,
496 p_overflow + i_overflow_size - ( p_slide + i_out_size ) );
500 memset( p_slide, 0, p_overflow + i_overflow_size - p_slide );
502 p_slide += i_out_size;
505 /* apply the atomic operations */
506 for( i = 0; i < p_filter->p_sys->i_nb_atomic_operations; i++ )
508 /* shorter variable names */
509 i_source_channel_offset
510 = p_filter->p_sys->p_atomic_operations[i].i_source_channel_offset;
511 i_dest_channel_offset
512 = p_filter->p_sys->p_atomic_operations[i].i_dest_channel_offset;
513 i_delay = p_filter->p_sys->p_atomic_operations[i].i_delay;
515 = p_filter->p_sys->p_atomic_operations[i].d_amplitude_factor;
517 if( p_out_buf->i_nb_samples > i_delay )
519 /* current buffer coefficients */
520 for( j = 0; j < p_out_buf->i_nb_samples - i_delay; j++ )
522 ((float*)p_out)[ (i_delay+j)*i_output_nb + i_dest_channel_offset ]
523 += p_in[ j * i_input_nb + i_source_channel_offset ]
524 * d_amplitude_factor;
527 /* overflow buffer coefficients */
528 for( j = 0; j < i_delay; j++ )
530 ((float*)p_overflow)[ j*i_output_nb + i_dest_channel_offset ]
531 += p_in[ (p_out_buf->i_nb_samples - i_delay + j)
532 * i_input_nb + i_source_channel_offset ]
533 * d_amplitude_factor;
538 /* overflow buffer coefficients only */
539 for( j = 0; j < p_out_buf->i_nb_samples; j++ )
541 ((float*)p_overflow)[ (i_delay - p_out_buf->i_nb_samples + j)
542 * i_output_nb + i_dest_channel_offset ]
543 += p_in[ j * i_input_nb + i_source_channel_offset ]
544 * d_amplitude_factor;
551 memset( p_out, 0, i_out_size );
558 /*****************************************************************************
560 *****************************************************************************/
561 static int OpenFilter( vlc_object_t *p_this )
563 filter_t *p_filter = (filter_t *)p_this;
566 /* Activate this filter only with stereo devices */
567 if( p_filter->fmt_out.audio.i_physical_channels
568 != (AOUT_CHAN_LEFT|AOUT_CHAN_RIGHT) )
570 msg_Dbg( p_filter, "filter discarded (incompatible format)" );
574 /* Request a specific format if not already compatible */
575 if( p_filter->fmt_in.audio.i_original_channels
576 != p_filter->fmt_out.audio.i_original_channels )
579 p_filter->fmt_in.audio.i_original_channels =
580 p_filter->fmt_out.audio.i_original_channels;
582 if( p_filter->fmt_in.audio.i_format != VLC_FOURCC('f','l','3','2')
583 || p_filter->fmt_out.audio.i_format != VLC_FOURCC('f','l','3','2') )
586 p_filter->fmt_in.audio.i_format = VLC_FOURCC('f','l','3','2');
587 p_filter->fmt_out.audio.i_format = VLC_FOURCC('f','l','3','2');
589 if( p_filter->fmt_in.audio.i_rate != p_filter->fmt_out.audio.i_rate )
592 p_filter->fmt_in.audio.i_rate = p_filter->fmt_out.audio.i_rate;
594 if( p_filter->fmt_in.audio.i_physical_channels == (AOUT_CHAN_LEFT|AOUT_CHAN_RIGHT)
595 && ( p_filter->fmt_in.audio.i_original_channels & AOUT_CHAN_DOLBYSTEREO )
596 && !config_GetInt( p_filter, "headphone-dolby" ) )
599 p_filter->fmt_in.audio.i_physical_channels = AOUT_CHAN_LEFT | AOUT_CHAN_RIGHT |
606 msg_Dbg( p_filter, "requesting specific format" );
610 /* Allocate the memory needed to store the module's structure */
611 p_filter->p_sys = malloc( sizeof(struct filter_sys_t) );
612 if( p_filter->p_sys == NULL )
614 p_filter->p_sys->i_overflow_buffer_size = 0;
615 p_filter->p_sys->p_overflow_buffer = NULL;
616 p_filter->p_sys->i_nb_atomic_operations = 0;
617 p_filter->p_sys->p_atomic_operations = NULL;
619 if( Init( VLC_OBJECT(p_filter), (struct aout_filter_sys_t *)p_filter->p_sys
620 , aout_FormatNbChannels ( &(p_filter->fmt_in.audio) )
621 , p_filter->fmt_in.audio.i_physical_channels
622 , p_filter->fmt_in.audio.i_rate ) < 0 )
624 free( p_filter->p_sys );
628 p_filter->pf_audio_filter = Convert;
629 p_filter->fmt_out.audio.i_rate = p_filter->fmt_in.audio.i_rate;
634 /*****************************************************************************
635 * CloseFilter : deallocate data structures
636 *****************************************************************************/
637 static void CloseFilter( vlc_object_t *p_this )
639 filter_t *p_filter = (filter_t *)p_this;
641 if( p_filter->p_sys != NULL )
643 free( p_filter->p_sys->p_overflow_buffer );
644 free( p_filter->p_sys->p_atomic_operations );
645 free( p_filter->p_sys );
646 p_filter->p_sys = NULL;
650 static block_t *Convert( filter_t *p_filter, block_t *p_block )
652 aout_filter_t aout_filter;
653 aout_buffer_t in_buf, out_buf;
657 if( !p_block || !p_block->i_samples )
660 block_Release( p_block );
664 i_out_size = p_block->i_samples *
665 p_filter->fmt_out.audio.i_bitspersample/8 *
666 aout_FormatNbChannels( &(p_filter->fmt_out.audio) );
668 p_out = p_filter->pf_audio_buffer_new( p_filter, i_out_size );
671 msg_Warn( p_filter, "can't get output buffer" );
672 block_Release( p_block );
676 p_out->i_samples = p_block->i_samples;
677 p_out->i_dts = p_block->i_dts;
678 p_out->i_pts = p_block->i_pts;
679 p_out->i_length = p_block->i_length;
681 aout_filter.p_sys = (struct aout_filter_sys_t *)p_filter->p_sys;
682 aout_filter.input = p_filter->fmt_in.audio;
683 aout_filter.input.i_format = p_filter->fmt_in.i_codec;
684 aout_filter.output = p_filter->fmt_out.audio;
685 aout_filter.output.i_format = p_filter->fmt_out.i_codec;
686 aout_filter.b_in_place = 0;
688 in_buf.p_buffer = p_block->p_buffer;
689 in_buf.i_nb_bytes = p_block->i_buffer;
690 in_buf.i_nb_samples = p_block->i_samples;
691 out_buf.p_buffer = p_out->p_buffer;
692 out_buf.i_nb_bytes = p_out->i_buffer;
693 out_buf.i_nb_samples = p_out->i_samples;
695 DoWork( (aout_instance_t *)p_filter, &aout_filter, &in_buf, &out_buf );
697 p_out->i_buffer = out_buf.i_nb_bytes;
698 p_out->i_samples = out_buf.i_nb_samples;
700 block_Release( p_block );