1 /*****************************************************************************
2 * linear.c : linear interpolation resampler
3 *****************************************************************************
4 * Copyright (C) 2002, 2006 the VideoLAN team
7 * Authors: Gildas Bazin <gbazin@netcourrier.com>
8 * Sigmund Augdal Helberg <dnumgis@videolan.org>
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 *****************************************************************************/
28 #include <stdlib.h> /* malloc(), free() */
32 #include "audio_output.h"
33 #include "aout_internal.h"
34 #include "vlc_filter.h"
35 #include "vlc_block.h"
37 /*****************************************************************************
39 *****************************************************************************/
40 static int Create ( vlc_object_t * );
41 static void Close ( vlc_object_t * );
42 static void DoWork ( aout_instance_t *, aout_filter_t *, aout_buffer_t *,
44 static void DoWork_inner( aout_instance_t *, aout_filter_t *, aout_buffer_t *,
45 aout_buffer_t *, int );
47 static int OpenFilter ( vlc_object_t * );
48 static void CloseFilter( vlc_object_t * );
49 static block_t *Resample( filter_t *, block_t * );
51 /*****************************************************************************
53 *****************************************************************************/
56 int32_t *p_prev_sample; /* this filter introduces a 1 sample delay */
58 unsigned int i_remainder; /* remainder of previous sample */
60 audio_date_t end_date;
63 /*****************************************************************************
65 *****************************************************************************/
67 set_description( _("Audio filter for linear interpolation resampling") );
68 set_category( CAT_AUDIO );
69 set_subcategory( SUBCAT_AUDIO_MISC );
70 set_capability( "audio filter", 5 );
71 set_callbacks( Create, Close );
74 set_description( _("Audio filter for linear interpolation resampling") );
75 set_capability( "audio filter2", 5 );
76 set_callbacks( OpenFilter, CloseFilter );
79 /*****************************************************************************
80 * Create: allocate linear resampler
81 *****************************************************************************/
82 static int Create( vlc_object_t *p_this )
84 aout_filter_t * p_filter = (aout_filter_t *)p_this;
85 struct filter_sys_t * p_sys;
87 if ( p_filter->input.i_rate == p_filter->output.i_rate
88 || p_filter->input.i_format != p_filter->output.i_format
89 || p_filter->input.i_physical_channels
90 != p_filter->output.i_physical_channels
91 || p_filter->input.i_original_channels
92 != p_filter->output.i_original_channels
93 || p_filter->input.i_format != VLC_FOURCC('f','l','3','2') )
98 /* Allocate the memory needed to store the module's structure */
99 p_sys = malloc( sizeof(filter_sys_t) );
100 p_filter->p_sys = (struct aout_filter_sys_t *)p_sys;
103 msg_Err( p_filter, "out of memory" );
106 p_sys->p_prev_sample = malloc(
107 p_filter->input.i_channels * sizeof(int32_t) );
108 if( p_sys->p_prev_sample == NULL )
110 msg_Err( p_filter, "out of memory" );
114 memset( p_sys->p_prev_sample, 0, aout_FormatNbChannels( &p_filter->input ) * sizeof(int32_t) );
116 p_filter->pf_do_work = DoWork;
118 /* We don't want a new buffer to be created because we're not sure we'll
119 * actually need to resample anything. */
120 p_filter->b_in_place = VLC_TRUE;
125 /*****************************************************************************
126 * Close: free our resources
127 *****************************************************************************/
128 static void Close( vlc_object_t * p_this )
130 aout_filter_t * p_filter = (aout_filter_t *)p_this;
131 filter_sys_t *p_sys = (filter_sys_t *)p_filter->p_sys;
133 free( p_sys->p_prev_sample );
137 /*****************************************************************************
138 * DoWork: convert a buffer
139 *****************************************************************************/
140 static void DoWork( aout_instance_t * p_aout, aout_filter_t * p_filter,
141 aout_buffer_t * p_in_buf, aout_buffer_t * p_out_buf )
143 DoWork_inner( p_aout, p_filter, p_in_buf, p_out_buf, p_aout->mixer.mixer.i_rate );
146 static void DoWork_inner( aout_instance_t * p_aout, aout_filter_t * p_filter,
147 aout_buffer_t * p_in_buf, aout_buffer_t * p_out_buf,
150 filter_sys_t *p_sys = (filter_sys_t *)p_filter->p_sys;
154 float *p_in, *p_out = (float *)p_out_buf->p_buffer;
155 float *p_prev_sample = (float *)p_sys->p_prev_sample;
157 int i_nb_channels = p_filter->input.i_channels;
158 int i_in_nb = p_in_buf->i_nb_samples;
159 int i_chan, i_in, i_out = 0;
162 /* Check if we really need to run the resampler */
163 //if( p_aout->mixer.mixer.i_rate == p_filter->input.i_rate )
164 if( i_output_rate == p_filter->input.i_rate )
166 if( p_filter->b_continuity &&
168 p_in_buf->i_nb_bytes + sizeof(float) * i_nb_channels )
170 /* output the whole thing with the last sample from last time */
171 memmove( ((float *)(p_in_buf->p_buffer)) + i_nb_channels,
172 p_in_buf->p_buffer, p_in_buf->i_nb_bytes );
173 memcpy( p_in_buf->p_buffer, p_prev_sample,
174 i_nb_channels * sizeof(float) );
176 p_filter->b_continuity = VLC_FALSE;
181 p_in = (float *)alloca( p_in_buf->i_nb_bytes );
183 p_in_orig = p_in = (float *)malloc( p_in_buf->i_nb_bytes );
190 p_aout->p_libvlc->pf_memcpy( p_in, p_in_buf->p_buffer, p_in_buf->i_nb_bytes );
192 /* Take care of the previous input sample (if any) */
193 if( !p_filter->b_continuity )
195 p_filter->b_continuity = VLC_TRUE;
196 p_sys->i_remainder = 0;
197 aout_DateInit( &p_sys->end_date, p_filter->output.i_rate );
201 while( p_sys->i_remainder < p_filter->output.i_rate )
203 for( i_chan = i_nb_channels ; i_chan ; )
206 p_out[i_chan] = p_prev_sample[i_chan];
207 p_out[i_chan] += ( ( p_in[i_chan] - p_prev_sample[i_chan] )
209 / p_filter->output.i_rate );
211 p_out += i_nb_channels;
214 p_sys->i_remainder += p_filter->input.i_rate;
216 p_sys->i_remainder -= p_filter->output.i_rate;
219 /* Take care of the current input samples (minus last one) */
220 for( i_in = 0; i_in < i_in_nb - 1; i_in++ )
222 while( p_sys->i_remainder < p_filter->output.i_rate )
224 for( i_chan = i_nb_channels ; i_chan ; )
227 p_out[i_chan] = p_in[i_chan];
228 p_out[i_chan] += ( ( p_in[i_chan + i_nb_channels]
230 * p_sys->i_remainder / p_filter->output.i_rate );
232 p_out += i_nb_channels;
235 p_sys->i_remainder += p_filter->input.i_rate;
238 p_in += i_nb_channels;
239 p_sys->i_remainder -= p_filter->output.i_rate;
242 /* Backup the last input sample for next time */
243 for( i_chan = i_nb_channels ; i_chan ; )
246 p_prev_sample[i_chan] = p_in[i_chan];
249 p_out_buf->i_nb_samples = i_out;
250 p_out_buf->start_date = p_in_buf->start_date;
252 if( p_in_buf->start_date !=
253 aout_DateGet( &p_sys->end_date ) )
255 aout_DateSet( &p_sys->end_date, p_in_buf->start_date );
258 p_out_buf->end_date = aout_DateIncrement( &p_sys->end_date,
259 p_out_buf->i_nb_samples );
261 p_out_buf->i_nb_bytes = p_out_buf->i_nb_samples *
262 i_nb_channels * sizeof(int32_t);
270 /*****************************************************************************
272 *****************************************************************************/
273 static int OpenFilter( vlc_object_t *p_this )
275 filter_t *p_filter = (filter_t *)p_this;
277 int i_out_rate = p_filter->fmt_out.audio.i_rate;
279 if( p_filter->fmt_in.audio.i_rate == p_filter->fmt_out.audio.i_rate ||
280 p_filter->fmt_in.i_codec != VLC_FOURCC('f','l','3','2') )
285 /* Allocate the memory needed to store the module's structure */
286 p_filter->p_sys = p_sys = malloc( sizeof(struct filter_sys_t) );
289 msg_Err( p_filter, "out of memory" );
293 p_sys->p_prev_sample = malloc(
294 p_filter->fmt_in.audio.i_channels * sizeof(int32_t) );
295 if( p_sys->p_prev_sample == NULL )
297 msg_Err( p_filter, "out of memory" );
302 memset( p_sys->p_prev_sample, 0, p_filter->fmt_in.audio.i_channels * sizeof(int32_t) );
304 p_filter->pf_audio_filter = Resample;
306 msg_Dbg( p_this, "%4.4s/%iKHz/%i->%4.4s/%iKHz/%i",
307 (char *)&p_filter->fmt_in.i_codec,
308 p_filter->fmt_in.audio.i_rate,
309 p_filter->fmt_in.audio.i_channels,
310 (char *)&p_filter->fmt_out.i_codec,
311 p_filter->fmt_out.audio.i_rate,
312 p_filter->fmt_out.audio.i_channels);
314 p_filter->fmt_out = p_filter->fmt_in;
315 p_filter->fmt_out.audio.i_rate = i_out_rate;
320 /*****************************************************************************
321 * CloseFilter : deallocate data structures
322 *****************************************************************************/
323 static void CloseFilter( vlc_object_t *p_this )
325 filter_t *p_filter = (filter_t *)p_this;
326 free( p_filter->p_sys->p_prev_sample );
327 free( p_filter->p_sys );
330 /*****************************************************************************
332 *****************************************************************************/
333 static block_t *Resample( filter_t *p_filter, block_t *p_block )
335 aout_filter_t aout_filter;
336 aout_buffer_t in_buf, out_buf;
339 int i_bytes_per_frame;
341 if( !p_block || !p_block->i_samples )
343 if( p_block ) p_block->pf_release( p_block );
347 i_bytes_per_frame = p_filter->fmt_out.audio.i_channels *
348 p_filter->fmt_out.audio.i_bitspersample / 8;
350 i_out_size = i_bytes_per_frame * ( 1 + (p_block->i_samples *
351 p_filter->fmt_out.audio.i_rate / p_filter->fmt_in.audio.i_rate));
353 p_out = p_filter->pf_audio_buffer_new( p_filter, i_out_size );
356 msg_Warn( p_filter, "can't get output buffer" );
357 p_block->pf_release( p_block );
361 p_out->i_samples = i_out_size / i_bytes_per_frame;
362 p_out->i_dts = p_block->i_dts;
363 p_out->i_pts = p_block->i_pts;
364 p_out->i_length = p_block->i_length;
366 aout_filter.p_sys = (struct aout_filter_sys_t *)p_filter->p_sys;
367 aout_filter.input = p_filter->fmt_in.audio;
368 aout_filter.output = p_filter->fmt_out.audio;
369 aout_filter.b_continuity = VLC_FALSE;
371 in_buf.p_buffer = p_block->p_buffer;
372 in_buf.i_nb_bytes = p_block->i_buffer;
373 in_buf.i_nb_samples = p_block->i_samples;
374 out_buf.p_buffer = p_out->p_buffer;
375 out_buf.i_nb_bytes = p_out->i_buffer;
376 out_buf.i_nb_samples = p_out->i_samples;
378 DoWork_inner( (aout_instance_t *)p_filter, &aout_filter, &in_buf, &out_buf,
379 p_filter->fmt_out.audio.i_rate );
381 p_block->pf_release( p_block );
383 p_out->i_buffer = out_buf.i_nb_bytes;
384 p_out->i_samples = out_buf.i_nb_samples;