ba6580d39a5fb2e88677b8718e3aa3eae243d25d
[vlc.git] / modules / audio_filter / channel_mixer / simple.c
1 /*****************************************************************************
2  * simple.c : simple channel mixer plug-in (only 7/7.1/5/5.1 -> Stereo for now)
3  *****************************************************************************
4  * Copyright (C) 2002, 2006 the VideoLAN team
5  * $Id$
6  *
7  * Authors: Gildas Bazin <gbazin@videolan.org>
8  *
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.
13  *
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.
18  *
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  *****************************************************************************/
23
24 /*****************************************************************************
25  * Preamble
26  *****************************************************************************/
27 #ifdef HAVE_CONFIG_H
28 # include "config.h"
29 #endif
30
31 #include <vlc_common.h>
32 #include <vlc_plugin.h>
33 #include <vlc_aout.h>
34 #include <vlc_filter.h>
35 #include <vlc_block.h>
36
37 /*****************************************************************************
38  * Module descriptor
39  *****************************************************************************/
40 static int  Create    ( vlc_object_t * );
41 static int  OpenFilter( vlc_object_t * );
42
43 vlc_module_begin();
44     set_description( N_("Audio filter for simple channel mixing") );
45     set_capability( "audio filter", 10 );
46     set_category( CAT_AUDIO );
47     set_subcategory( SUBCAT_AUDIO_MISC );
48     set_callbacks( Create, NULL );
49
50     add_submodule();
51     set_description( N_("audio filter for simple channel mixing") );
52     set_capability( "audio filter2", 10 );
53     set_callbacks( OpenFilter, NULL );
54 vlc_module_end();
55
56 /*****************************************************************************
57  * Local prototypes
58  *****************************************************************************/
59 #define AOUT_CHANS_STEREO_FRONT  ( AOUT_CHAN_LEFT | AOUT_CHAN_RIGHT )
60 #define AOUT_CHANS_STEREO_REAR   ( AOUT_CHAN_REARLEFT | AOUT_CHAN_REARRIGHT )
61 #define AOUT_CHANS_STEREO_MIDDLE (AOUT_CHAN_MIDDLELEFT | AOUT_CHAN_MIDDLERIGHT )
62
63 #define AOUT_CHANS_2_0 AOUT_CHANS_STEREO_FRONT
64 #define AOUT_CHANS_4_0 (AOUT_CHANS_STEREO_FRONT | AOUT_CHANS_STEREO_REAR )
65 #define AOUT_CHANS_5_0 ( AOUT_CHANS_4_0 | AOUT_CHAN_CENTER )
66 #define AOUT_CHANS_6_0 (AOUT_CHANS_STEREO_FRONT | AOUT_CHANS_STEREO_REAR | AOUT_CHANS_STEREO_MIDDLE )
67 #define AOUT_CHANS_7_0 ( AOUT_CHANS_6_0 | AOUT_CHAN_CENTER )
68
69 static bool IsSupported( const audio_format_t *p_input, const audio_format_t *p_output );
70
71 static void DoWork    ( aout_instance_t *, aout_filter_t *, aout_buffer_t *,
72                         aout_buffer_t * );
73
74 static block_t *Filter( filter_t *, block_t * );
75
76 /*****************************************************************************
77  * Create: allocate trivial channel mixer
78  *****************************************************************************/
79 static int Create( vlc_object_t *p_this )
80 {
81     aout_filter_t * p_filter = (aout_filter_t *)p_this;
82
83     if( !IsSupported( &p_filter->input, &p_filter->output ) )
84         return -1;
85
86     p_filter->pf_do_work = DoWork;
87     p_filter->b_in_place = 0;
88
89     return 0;
90 }
91
92 /*****************************************************************************
93  * DoWork: convert a buffer
94  *****************************************************************************/
95 static void DoWork( aout_instance_t * p_aout, aout_filter_t * p_filter,
96                     aout_buffer_t * p_in_buf, aout_buffer_t * p_out_buf )
97 {
98     VLC_UNUSED(p_aout);
99     int i_input_nb = aout_FormatNbChannels( &p_filter->input );
100     int i_output_nb = aout_FormatNbChannels( &p_filter->output );
101     float *p_dest = (float *)p_out_buf->p_buffer;
102     const float *p_src = (const float *)p_in_buf->p_buffer;
103     int i;
104
105     p_out_buf->i_nb_samples = p_in_buf->i_nb_samples;
106     p_out_buf->i_nb_bytes = p_in_buf->i_nb_bytes * i_output_nb / i_input_nb;
107
108     if( p_filter->output.i_physical_channels == AOUT_CHANS_2_0 )
109     {
110         if( p_filter->input.i_physical_channels & AOUT_CHAN_MIDDLELEFT )
111         for( i = p_in_buf->i_nb_samples; i--; )
112         {
113             *p_dest = p_src[6] + 0.5 * p_src[0] + p_src[2] / 4 + p_src[4] / 4;
114             p_dest++;
115             *p_dest = p_src[6] + 0.5 * p_src[1] + p_src[3] / 4 + p_src[5] / 4;
116             p_dest++;
117
118             p_src += 7;
119
120             if( p_filter->input.i_physical_channels & AOUT_CHAN_LFE ) p_src++;
121         }
122         else
123         for( i = p_in_buf->i_nb_samples; i--; )
124         {
125             *p_dest = p_src[4] + 0.5 * p_src[0] + 0.33 * p_src[2];
126             p_dest++;
127             *p_dest = p_src[4] + 0.5 * p_src[1] + 0.33 * p_src[3];
128             p_dest++;
129
130             p_src += 5;
131
132             if( p_filter->input.i_physical_channels & AOUT_CHAN_LFE ) p_src++;
133         }
134     }
135     else if( p_filter->output.i_physical_channels == AOUT_CHAN_CENTER )
136     {
137         if( p_filter->input.i_physical_channels & AOUT_CHAN_MIDDLELEFT )
138         for( i = p_in_buf->i_nb_samples; i--; )
139         {
140             *p_dest = p_src[6] + p_src[0] / 4 + p_src[1] / 4 + p_src[2] / 8 + p_src[3] / 8 + p_src[4] / 8 + p_src[5] / 8;
141             p_dest++;
142
143             p_src += 7;
144
145             if( p_filter->input.i_physical_channels & AOUT_CHAN_LFE ) p_src++;
146         }
147         else if( p_filter->input.i_physical_channels & AOUT_CHAN_REARLEFT )
148         for( i = p_in_buf->i_nb_samples; i--; )
149         {
150             *p_dest = p_src[4] + p_src[0] / 4 + p_src[1] / 4 + p_src[2] / 6 + p_src[3] / 6;
151             p_dest++;
152
153             p_src += 5;
154
155             if( p_filter->input.i_physical_channels & AOUT_CHAN_LFE ) p_src++;
156         }
157         else
158         for( i = p_in_buf->i_nb_samples; i--; )
159         {
160             *p_dest = p_src[0] / 2 + p_src[1] / 2;
161             p_dest++;
162
163             p_src += 2;
164         }
165     }
166     else
167     {
168         if( p_filter->input.i_physical_channels & AOUT_CHAN_MIDDLELEFT )
169         for( i = p_in_buf->i_nb_samples; i--; )
170         {
171             *p_dest = p_src[6] + 0.5 * p_src[0] + p_src[2] / 6;
172             p_dest++;
173             *p_dest = p_src[6] + 0.5 * p_src[1] + p_src[3] / 6;
174             p_dest++;
175             *p_dest = p_src[2] / 6 +  p_src[4];
176             p_dest++;
177             *p_dest = p_src[3] / 6 +  p_src[5];
178             p_dest++;
179
180             p_src += 7;
181
182             if( p_filter->input.i_physical_channels & AOUT_CHAN_LFE ) p_src++;
183         }
184         else
185         for( i = p_in_buf->i_nb_samples; i--; )
186         {
187             *p_dest = p_src[4] + 0.5 * p_src[0];
188             p_dest++;
189             *p_dest = p_src[4] + 0.5 * p_src[1];
190             p_dest++;
191             *p_dest = p_src[2];
192             p_dest++;
193             *p_dest = p_src[3];
194             p_dest++;
195
196             p_src += 5;
197
198             if( p_filter->input.i_physical_channels & AOUT_CHAN_LFE ) p_src++;
199         }
200     }
201 }
202
203 /*****************************************************************************
204  * OpenFilter:
205  *****************************************************************************/
206 static int OpenFilter( vlc_object_t *p_this )
207 {
208     filter_t *p_filter = (filter_t *)p_this;
209
210     audio_format_t fmt_in  = p_filter->fmt_in.audio;
211     audio_format_t fmt_out = p_filter->fmt_out.audio;
212
213     fmt_in.i_format = p_filter->fmt_in.i_codec;
214     fmt_out.i_format = p_filter->fmt_out.i_codec;
215
216     if( !IsSupported( &fmt_in, &fmt_out ) )
217         return -1;
218
219     p_filter->pf_audio_filter = Filter;
220
221     return 0;
222 }
223
224 /*****************************************************************************
225  * Filter:
226  *****************************************************************************/
227 static block_t *Filter( filter_t *p_filter, block_t *p_block )
228 {
229     aout_filter_t aout_filter;
230     aout_buffer_t in_buf, out_buf;
231     block_t *p_out;
232     int i_out_size;
233
234     if( !p_block || !p_block->i_samples )
235     {
236         if( p_block ) p_block->pf_release( p_block );
237         return NULL;
238     }
239
240     i_out_size = p_block->i_samples *
241       p_filter->fmt_out.audio.i_bitspersample *
242         p_filter->fmt_out.audio.i_channels / 8;
243
244     p_out = p_filter->pf_audio_buffer_new( p_filter, i_out_size );
245     if( !p_out )
246     {
247         msg_Warn( p_filter, "can't get output buffer" );
248         p_block->pf_release( p_block );
249         return NULL;
250     }
251
252     p_out->i_samples = p_block->i_samples;
253     p_out->i_dts = p_block->i_dts;
254     p_out->i_pts = p_block->i_pts;
255     p_out->i_length = p_block->i_length;
256
257     aout_filter.p_sys = (struct aout_filter_sys_t *)p_filter->p_sys;
258     aout_filter.input = p_filter->fmt_in.audio;
259     aout_filter.input.i_format = p_filter->fmt_in.i_codec;
260     aout_filter.output = p_filter->fmt_out.audio;
261     aout_filter.output.i_format = p_filter->fmt_out.i_codec;
262
263     in_buf.p_buffer = p_block->p_buffer;
264     in_buf.i_nb_bytes = p_block->i_buffer;
265     in_buf.i_nb_samples = p_block->i_samples;
266     out_buf.p_buffer = p_out->p_buffer;
267     out_buf.i_nb_bytes = p_out->i_buffer;
268     out_buf.i_nb_samples = p_out->i_samples;
269
270     DoWork( (aout_instance_t *)p_filter, &aout_filter, &in_buf, &out_buf );
271
272     p_block->pf_release( p_block );
273
274     p_out->i_buffer = out_buf.i_nb_bytes;
275     p_out->i_samples = out_buf.i_nb_samples;
276
277     return p_out;
278 }
279
280 /*****************************************************************************
281  * Helpers:
282  *****************************************************************************/
283 static bool IsSupported( const audio_format_t *p_input, const audio_format_t *p_output )
284 {
285     if ( (p_input->i_physical_channels
286            == p_output->i_physical_channels
287            && p_input->i_original_channels
288                == p_output->i_original_channels)
289           || p_input->i_format != p_output->i_format
290           || p_input->i_rate != p_output->i_rate
291           || p_input->i_format != VLC_FOURCC('f','l','3','2') )
292     {
293         return false;
294     }
295
296     /* Only conversion to Mono, Stereo and 4.0 right now */
297     if( p_output->i_physical_channels != AOUT_CHAN_CENTER &&
298         p_output->i_physical_channels != AOUT_CHANS_2_0 &&
299         p_output->i_physical_channels != AOUT_CHANS_4_0 )
300     {
301         return false;
302     }
303
304     /* Only from 7/7.1/5/5.1/2.0 */
305     if( (p_input->i_physical_channels & ~AOUT_CHAN_LFE) != AOUT_CHANS_7_0 &&
306         (p_input->i_physical_channels & ~AOUT_CHAN_LFE) != AOUT_CHANS_5_0 &&
307          p_input->i_physical_channels != AOUT_CHANS_2_0 )
308     {
309         return false;
310     }
311     return true;
312 }