* all: added a new access_filter module: record + one hotkey to start/stop
[vlc.git] / modules / audio_filter / resampler / linear.c
1 /*****************************************************************************
2  * linear.c : linear interpolation resampler
3  *****************************************************************************
4  * Copyright (C) 2002 VideoLAN
5  * $Id$
6  *
7  * Authors: Gildas Bazin <gbazin@netcourrier.com>
8  *          Sigmund Augdal <sigmunau@idi.ntnu.no>
9  *
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.
14  *
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.
19  *
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., 59 Temple Place - Suite 330, Boston, MA  02111, USA.
23  *****************************************************************************/
24
25 /*****************************************************************************
26  * Preamble
27  *****************************************************************************/
28 #include <stdlib.h>                                      /* malloc(), free() */
29 #include <string.h>
30
31 #include <vlc/vlc.h>
32 #include "audio_output.h"
33 #include "aout_internal.h"
34 #include "vlc_filter.h"
35 #include "vlc_block.h"
36
37 /*****************************************************************************
38  * Local prototypes
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 *,
43                         aout_buffer_t * );
44
45 static int  OpenFilter ( vlc_object_t * );
46 static void CloseFilter( vlc_object_t * );
47 static block_t *Resample( filter_t *, block_t * );
48
49 /*****************************************************************************
50  * Local structures
51  *****************************************************************************/
52 struct filter_sys_t
53 {
54     int32_t *p_prev_sample;       /* this filter introduces a 1 sample delay */
55
56     unsigned int i_remainder;                /* remainder of previous sample */
57
58     audio_date_t end_date;
59 };
60
61 /*****************************************************************************
62  * Module descriptor
63  *****************************************************************************/
64 vlc_module_begin();
65     set_description( _("audio filter for linear interpolation resampling") );
66     set_category( CAT_AUDIO );
67     set_subcategory( SUBCAT_AUDIO_MISC );
68     set_capability( "audio filter", 5 );
69     set_callbacks( Create, Close );
70
71     add_submodule();
72     set_description( _("audio filter for linear interpolation resampling") );
73     set_capability( "audio filter2", 5 );
74     set_callbacks( OpenFilter, CloseFilter );
75 vlc_module_end();
76
77 /*****************************************************************************
78  * Create: allocate linear resampler
79  *****************************************************************************/
80 static int Create( vlc_object_t *p_this )
81 {
82     aout_filter_t * p_filter = (aout_filter_t *)p_this;
83     struct filter_sys_t * p_sys;
84     
85     if ( p_filter->input.i_rate == p_filter->output.i_rate
86           || p_filter->input.i_format != p_filter->output.i_format
87           || p_filter->input.i_physical_channels
88               != p_filter->output.i_physical_channels
89           || p_filter->input.i_original_channels
90               != p_filter->output.i_original_channels
91           || p_filter->input.i_format != VLC_FOURCC('f','l','3','2') )
92     {
93         return VLC_EGENERIC;
94     }
95
96     /* Allocate the memory needed to store the module's structure */
97     p_sys = malloc( sizeof(filter_sys_t) );
98     p_filter->p_sys = (struct aout_filter_sys_t *)p_sys;
99     if( p_sys == NULL )
100     {
101         msg_Err( p_filter, "out of memory" );
102         return VLC_ENOMEM;
103     }
104     p_sys->p_prev_sample = malloc(
105         aout_FormatNbChannels( &p_filter->input ) * sizeof(int32_t) );
106     if( p_sys->p_prev_sample == NULL )
107     {
108         msg_Err( p_filter, "out of memory" );
109         return VLC_ENOMEM;
110     }
111
112     p_filter->pf_do_work = DoWork;
113
114     /* We don't want a new buffer to be created because we're not sure we'll
115      * actually need to resample anything. */
116     p_filter->b_in_place = VLC_TRUE;
117
118     return VLC_SUCCESS;
119 }
120
121 /*****************************************************************************
122  * Close: free our resources
123  *****************************************************************************/
124 static void Close( vlc_object_t * p_this )
125 {
126     aout_filter_t * p_filter = (aout_filter_t *)p_this;
127     filter_sys_t *p_sys = (filter_sys_t *)p_filter->p_sys;
128     
129     free( p_sys->p_prev_sample );
130     free( p_sys );
131 }
132
133 /*****************************************************************************
134  * DoWork: convert a buffer
135  *****************************************************************************/
136 static void DoWork( aout_instance_t * p_aout, aout_filter_t * p_filter,
137                     aout_buffer_t * p_in_buf, aout_buffer_t * p_out_buf )
138 {
139     filter_sys_t *p_sys = (filter_sys_t *)p_filter->p_sys;
140     float *p_in, *p_out = (float *)p_out_buf->p_buffer;
141     float *p_prev_sample = (float *)p_sys->p_prev_sample;
142
143     int i_nb_channels = aout_FormatNbChannels( &p_filter->input );
144     int i_in_nb = p_in_buf->i_nb_samples;
145     int i_chan, i_in, i_out = 0;
146
147     /* Check if we really need to run the resampler */
148     if( p_aout->mixer.mixer.i_rate == p_filter->input.i_rate )
149     {
150         if( p_filter->b_continuity &&
151             p_in_buf->i_size >=
152               p_in_buf->i_nb_bytes + sizeof(float) * i_nb_channels )
153         {
154             /* output the whole thing with the last sample from last time */
155             memmove( ((float *)(p_in_buf->p_buffer)) + i_nb_channels,
156                      p_in_buf->p_buffer, p_in_buf->i_nb_bytes );
157             memcpy( p_in_buf->p_buffer, p_prev_sample,
158                     i_nb_channels * sizeof(float) );
159         }
160         p_filter->b_continuity = VLC_FALSE;
161         return;
162     }
163
164 #ifdef HAVE_ALLOCA
165     p_in = (float *)alloca( p_in_buf->i_nb_bytes );
166 #else
167     p_in_orig = p_in = (float *)malloc( p_in_buf->i_nb_bytes );
168 #endif
169     if( p_in == NULL )
170     {
171         return;
172     }
173
174     p_aout->p_vlc->pf_memcpy( p_in, p_in_buf->p_buffer, p_in_buf->i_nb_bytes );
175
176     /* Take care of the previous input sample (if any) */
177     if( !p_filter->b_continuity )
178     {
179         p_filter->b_continuity = VLC_TRUE;
180         p_sys->i_remainder = 0;
181         aout_DateInit( &p_sys->end_date, p_filter->output.i_rate );
182     }
183     else
184     {
185         while( p_sys->i_remainder < p_filter->output.i_rate )
186         {
187             for( i_chan = i_nb_channels ; i_chan ; )
188             {
189                 i_chan--;
190                 p_out[i_chan] = p_prev_sample[i_chan];
191                 p_out[i_chan] += ( (p_prev_sample[i_chan] - p_in[i_chan])
192                                    * p_sys->i_remainder
193                                    / p_filter->output.i_rate );
194             }
195             p_out += i_nb_channels;
196               i_out++;
197
198             p_sys->i_remainder += p_filter->input.i_rate;
199         }
200         p_sys->i_remainder -= p_filter->output.i_rate;
201     }
202
203     /* Take care of the current input samples (minus last one) */
204     for( i_in = 0; i_in < i_in_nb - 1; i_in++ )
205     {
206         while( p_sys->i_remainder < p_filter->output.i_rate )
207         {
208             for( i_chan = i_nb_channels ; i_chan ; )
209             {
210                 i_chan--;
211                 p_out[i_chan] = p_in[i_chan];
212                 p_out[i_chan] += ( (p_in[i_chan] -
213                     p_in[i_chan + i_nb_channels])
214                     * p_sys->i_remainder / p_filter->output.i_rate );
215             }
216             p_out += i_nb_channels;
217               i_out++;
218
219             p_sys->i_remainder += p_filter->input.i_rate;
220         }
221
222         p_in += i_nb_channels;
223         p_sys->i_remainder -= p_filter->output.i_rate;
224     }
225
226     /* Backup the last input sample for next time */
227     for( i_chan = i_nb_channels ; i_chan ; )
228     {
229         i_chan--;
230         p_prev_sample[i_chan] = p_in[i_chan];
231     }
232
233     p_out_buf->i_nb_samples = i_out;
234     p_out_buf->start_date = p_in_buf->start_date;
235
236     if( p_in_buf->start_date !=
237         aout_DateGet( &p_sys->end_date ) )
238     {
239         aout_DateSet( &p_sys->end_date, p_in_buf->start_date );
240     }
241
242     p_out_buf->end_date = aout_DateIncrement( &p_sys->end_date,
243                                               p_out_buf->i_nb_samples );
244
245     p_out_buf->i_nb_bytes = p_out_buf->i_nb_samples *
246         i_nb_channels * sizeof(int32_t);
247
248 #ifndef HAVE_ALLOCA
249     free( p_in_orig );
250 #endif
251
252 }
253
254 /*****************************************************************************
255  * OpenFilter:
256  *****************************************************************************/
257 static int OpenFilter( vlc_object_t *p_this )
258 {
259     filter_t *p_filter = (filter_t *)p_this;
260     filter_sys_t *p_sys;
261     int i_out_rate  = p_filter->fmt_out.audio.i_rate;
262
263     if( p_filter->fmt_in.audio.i_rate == p_filter->fmt_out.audio.i_rate ||
264         p_filter->fmt_in.i_codec != VLC_FOURCC('f','l','3','2') )
265     {
266         return VLC_EGENERIC;
267     }
268     
269     /* Allocate the memory needed to store the module's structure */
270     p_filter->p_sys = p_sys = malloc( sizeof(struct filter_sys_t) );
271     if( p_sys == NULL )
272     {
273         msg_Err( p_filter, "out of memory" );
274         return VLC_ENOMEM;
275     }
276
277     p_sys->p_prev_sample = malloc(
278         p_filter->fmt_in.audio.i_channels * sizeof(int32_t) );
279     if( p_sys->p_prev_sample == NULL )
280     {
281         msg_Err( p_filter, "out of memory" );
282         free( p_sys );
283         return VLC_ENOMEM;
284     }
285
286     p_filter->pf_audio_filter = Resample;
287
288     msg_Dbg( p_this, "%4.4s/%iKHz/%i->%4.4s/%iKHz/%i",
289              (char *)&p_filter->fmt_in.i_codec,
290              p_filter->fmt_in.audio.i_rate,
291              p_filter->fmt_in.audio.i_channels,
292              (char *)&p_filter->fmt_out.i_codec,
293              p_filter->fmt_out.audio.i_rate,
294              p_filter->fmt_out.audio.i_channels);
295
296     p_filter->fmt_out = p_filter->fmt_in;
297     p_filter->fmt_out.audio.i_rate = i_out_rate;
298
299     return 0;
300 }
301
302 /*****************************************************************************
303  * CloseFilter : deallocate data structures
304  *****************************************************************************/
305 static void CloseFilter( vlc_object_t *p_this )
306 {
307     filter_t *p_filter = (filter_t *)p_this;
308     free( p_filter->p_sys->p_prev_sample );
309     free( p_filter->p_sys );
310 }
311
312 /*****************************************************************************
313  * Resample
314  *****************************************************************************/
315 static block_t *Resample( filter_t *p_filter, block_t *p_block )
316 {
317     aout_filter_t aout_filter;
318     aout_buffer_t in_buf, out_buf;
319     block_t *p_out;
320     int i_out_size;
321     int i_bytes_per_frame;
322
323     if( !p_block || !p_block->i_samples )
324     {
325         if( p_block ) p_block->pf_release( p_block );
326         return NULL;
327     }
328     
329     i_bytes_per_frame = p_filter->fmt_out.audio.i_channels *
330                   p_filter->fmt_out.audio.i_bitspersample / 8;
331     
332     i_out_size = i_bytes_per_frame * ( 1 + (p_block->i_samples * 
333         p_filter->fmt_out.audio.i_rate / p_filter->fmt_in.audio.i_rate));
334
335     p_out = p_filter->pf_audio_buffer_new( p_filter, i_out_size );
336     if( !p_out )
337     {
338         msg_Warn( p_filter, "can't get output buffer" );
339         p_block->pf_release( p_block );
340         return NULL;
341     }
342
343     p_out->i_samples = i_out_size / i_bytes_per_frame;
344     p_out->i_dts = p_block->i_dts;
345     p_out->i_pts = p_block->i_pts;
346     p_out->i_length = p_block->i_length;
347
348     aout_filter.p_sys = (struct aout_filter_sys_t *)p_filter->p_sys;
349     aout_filter.input = p_filter->fmt_in.audio;
350     aout_filter.output = p_filter->fmt_out.audio;
351     aout_filter.b_continuity = VLC_FALSE;
352
353     in_buf.p_buffer = p_block->p_buffer;
354     in_buf.i_nb_bytes = p_block->i_buffer;
355     in_buf.i_nb_samples = p_block->i_samples;
356     out_buf.p_buffer = p_out->p_buffer;
357     out_buf.i_nb_bytes = p_out->i_buffer;
358     out_buf.i_nb_samples = p_out->i_samples;
359
360     DoWork( (aout_instance_t *)p_filter, &aout_filter, &in_buf, &out_buf );
361
362     p_block->pf_release( p_block );
363     
364     p_out->i_buffer = out_buf.i_nb_bytes;
365     p_out->i_samples = out_buf.i_nb_samples;
366
367     return p_out;
368 }