git.sesse.net Git - vlc/blob - 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/vlc.h>
  32 #include <vlc_aout.h>
  33 #include <vlc_filter.h>
  34 #include <vlc_block.h>
  35
  36 /*****************************************************************************
  37  * Local prototypes
  38  *****************************************************************************/
  39 static int  Create    ( vlc_object_t * );
  40
  41 static void DoWork    ( aout_instance_t *, aout_filter_t *, aout_buffer_t *,
  42                         aout_buffer_t * );
  43
  44 static int  OpenFilter ( vlc_object_t * );
  45 static block_t *Filter( filter_t *, block_t * );
  46
  47 /*****************************************************************************
  48  * Module descriptor
  49  *****************************************************************************/
  50 vlc_module_begin();
  51     set_description( _("Audio filter for simple channel mixing") );
  52     set_capability( "audio filter", 10 );
  53     set_category( CAT_AUDIO );
  54     set_subcategory( SUBCAT_AUDIO_MISC );
  55     set_callbacks( Create, NULL );
  56
  57     add_submodule();
  58     set_description( _("audio filter for simple channel mixing") );
  59     set_capability( "audio filter2", 10 );
  60     set_callbacks( OpenFilter, NULL );
  61 vlc_module_end();
  62
  63 /*****************************************************************************
  64  * Create: allocate trivial channel mixer
  65  *****************************************************************************/
  66 static int Create( vlc_object_t *p_this )
  67 {
  68     aout_filter_t * p_filter = (aout_filter_t *)p_this;
  69
  70     if ( (p_filter->input.i_physical_channels
  71            == p_filter->output.i_physical_channels
  72            && p_filter->input.i_original_channels
  73                == p_filter->output.i_original_channels)
  74           || p_filter->input.i_format != p_filter->output.i_format
  75           || p_filter->input.i_rate != p_filter->output.i_rate
  76           || p_filter->input.i_format != VLC_FOURCC('f','l','3','2') )
  77     {
  78         return -1;
  79     }
  80
  81     /* Only conversion to Mono, Stereo and 4.0 right now */
  82     if( p_filter->output.i_physical_channels !=
  83         (AOUT_CHAN_LEFT | AOUT_CHAN_RIGHT)
  84         && p_filter->output.i_physical_channels !=
  85         ( AOUT_CHAN_LEFT | AOUT_CHAN_RIGHT |
  86         AOUT_CHAN_REARLEFT | AOUT_CHAN_REARRIGHT)
  87         && p_filter->output.i_physical_channels != AOUT_CHAN_CENTER )
  88     {
  89         return -1;
  90     }
  91
  92     /* Only from 7/7.1/5/5.1/2.0 */
  93     if( (p_filter->input.i_physical_channels & ~AOUT_CHAN_LFE) !=
  94         (AOUT_CHAN_LEFT | AOUT_CHAN_RIGHT | AOUT_CHAN_CENTER |
  95          AOUT_CHAN_REARLEFT | AOUT_CHAN_REARRIGHT) &&
  96         (p_filter->input.i_physical_channels & ~AOUT_CHAN_LFE) !=
  97         (AOUT_CHAN_LEFT | AOUT_CHAN_RIGHT | AOUT_CHAN_CENTER |
  98          AOUT_CHAN_MIDDLELEFT | AOUT_CHAN_MIDDLERIGHT |
  99          AOUT_CHAN_REARLEFT | AOUT_CHAN_REARRIGHT) &&
 100         p_filter->input.i_physical_channels !=
 101         (AOUT_CHAN_LEFT | AOUT_CHAN_RIGHT) )
 102     {
 103         return -1;
 104     }
 105
 106     p_filter->pf_do_work = DoWork;
 107     p_filter->b_in_place = 0;
 108
 109     return 0;
 110 }
 111
 112 /*****************************************************************************
 113  * DoWork: convert a buffer
 114  *****************************************************************************/
 115 static void DoWork( aout_instance_t * p_aout, aout_filter_t * p_filter,
 116                     aout_buffer_t * p_in_buf, aout_buffer_t * p_out_buf )
 117 {
 118     VLC_UNUSED(p_aout);
 119     int i_input_nb = aout_FormatNbChannels( &p_filter->input );
 120     int i_output_nb = aout_FormatNbChannels( &p_filter->output );
 121     float *p_dest = (float *)p_out_buf->p_buffer;
 122     float *p_src = (float *)p_in_buf->p_buffer;
 123     int i;
 124
 125     p_out_buf->i_nb_samples = p_in_buf->i_nb_samples;
 126     p_out_buf->i_nb_bytes = p_in_buf->i_nb_bytes * i_output_nb / i_input_nb;
 127
 128     if( p_filter->output.i_physical_channels ==
 129                             (AOUT_CHAN_LEFT | AOUT_CHAN_RIGHT) )
 130     {
 131         if( p_filter->input.i_physical_channels & AOUT_CHAN_MIDDLELEFT )
 132         for( i = p_in_buf->i_nb_samples; i--; )
 133         {
 134             *p_dest = p_src[6] + 0.5 * p_src[0] + p_src[2] / 4 + p_src[4] / 4;
 135             p_dest++;
 136             *p_dest = p_src[6] + 0.5 * p_src[1] + p_src[3] / 4 + p_src[5] / 4;
 137             p_dest++;
 138
 139             p_src += 7;
 140
 141             if( p_filter->input.i_physical_channels & AOUT_CHAN_LFE ) p_src++;
 142         }
 143         else
 144         for( i = p_in_buf->i_nb_samples; i--; )
 145         {
 146             *p_dest = p_src[4] + 0.5 * p_src[0] + 0.33 * p_src[2];
 147             p_dest++;
 148             *p_dest = p_src[4] + 0.5 * p_src[1] + 0.33 * p_src[3];
 149             p_dest++;
 150
 151             p_src += 5;
 152
 153             if( p_filter->input.i_physical_channels & AOUT_CHAN_LFE ) p_src++;
 154         }
 155     }
 156     else if( p_filter->output.i_physical_channels == AOUT_CHAN_CENTER )
 157     {
 158         if( p_filter->input.i_physical_channels & AOUT_CHAN_MIDDLELEFT )
 159         for( i = p_in_buf->i_nb_samples; i--; )
 160         {
 161             *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;
 162             p_dest++;
 163
 164             p_src += 7;
 165
 166             if( p_filter->input.i_physical_channels & AOUT_CHAN_LFE ) p_src++;
 167         }
 168         else if( p_filter->input.i_physical_channels & AOUT_CHAN_REARLEFT )
 169         for( i = p_in_buf->i_nb_samples; i--; )
 170         {
 171             *p_dest = p_src[4] + p_src[0] / 4 + p_src[1] / 4 + p_src[2] / 6 + p_src[3] / 6;
 172             p_dest++;
 173
 174             p_src += 5;
 175
 176             if( p_filter->input.i_physical_channels & AOUT_CHAN_LFE ) p_src++;
 177         }
 178         else
 179         for( i = p_in_buf->i_nb_samples; i--; )
 180         {
 181             *p_dest = p_src[0] / 2 + p_src[1] / 2;
 182             p_dest++;
 183
 184             p_src += 2;
 185         }
 186     }
 187     else
 188     {
 189         if( p_filter->input.i_physical_channels & AOUT_CHAN_MIDDLELEFT )
 190         for( i = p_in_buf->i_nb_samples; i--; )
 191         {
 192             *p_dest = p_src[6] + 0.5 * p_src[0] + p_src[2] / 6;
 193             p_dest++;
 194             *p_dest = p_src[6] + 0.5 * p_src[1] + p_src[3] / 6;
 195             p_dest++;
 196             *p_dest = p_src[2] / 6 +  p_src[4];
 197             p_dest++;
 198             *p_dest = p_src[3] / 6 +  p_src[5];
 199             p_dest++;
 200
 201             p_src += 7;
 202
 203             if( p_filter->input.i_physical_channels & AOUT_CHAN_LFE ) p_src++;
 204         }
 205         else
 206         for( i = p_in_buf->i_nb_samples; i--; )
 207         {
 208             *p_dest = p_src[4] + 0.5 * p_src[0];
 209             p_dest++;
 210             *p_dest = p_src[4] + 0.5 * p_src[1];
 211             p_dest++;
 212             *p_dest = p_src[2];
 213             p_dest++;
 214             *p_dest = p_src[3];
 215             p_dest++;
 216
 217             p_src += 5;
 218
 219             if( p_filter->input.i_physical_channels & AOUT_CHAN_LFE ) p_src++;
 220         }
 221
 222     }
 223 }
 224
 225 /*****************************************************************************
 226  * OpenFilter:
 227  *****************************************************************************/
 228 static int OpenFilter( vlc_object_t *p_this )
 229 {
 230     filter_t *p_filter = (filter_t *)p_this;
 231
 232     if ( (p_filter->fmt_in.audio.i_physical_channels
 233            == p_filter->fmt_out.audio.i_physical_channels
 234            && p_filter->fmt_in.audio.i_original_channels
 235                == p_filter->fmt_out.audio.i_original_channels)
 236           || p_filter->fmt_in.i_codec != p_filter->fmt_out.i_codec
 237           || p_filter->fmt_in.audio.i_rate != p_filter->fmt_out.audio.i_rate
 238           || p_filter->fmt_in.i_codec != VLC_FOURCC('f','l','3','2') )
 239     {
 240         return -1;
 241     }
 242
 243     /* Only conversion to Mono, Stereo and 4.0 right now */
 244     if( p_filter->fmt_out.audio.i_physical_channels !=
 245         (AOUT_CHAN_LEFT | AOUT_CHAN_RIGHT)
 246         && p_filter->fmt_out.audio.i_physical_channels !=
 247         ( AOUT_CHAN_LEFT | AOUT_CHAN_RIGHT |
 248         AOUT_CHAN_REARLEFT | AOUT_CHAN_REARRIGHT)
 249         && p_filter->fmt_out.audio.i_physical_channels != AOUT_CHAN_CENTER )
 250     {
 251         return -1;
 252     }
 253
 254     /* Only from 7/7.1/5/5.1/2.0 */
 255     if( (p_filter->fmt_in.audio.i_physical_channels & ~AOUT_CHAN_LFE) !=
 256         (AOUT_CHAN_LEFT | AOUT_CHAN_RIGHT | AOUT_CHAN_CENTER |
 257          AOUT_CHAN_REARLEFT | AOUT_CHAN_REARRIGHT) &&
 258         (p_filter->fmt_in.audio.i_physical_channels & ~AOUT_CHAN_LFE) !=
 259         (AOUT_CHAN_LEFT | AOUT_CHAN_RIGHT | AOUT_CHAN_CENTER |
 260          AOUT_CHAN_MIDDLELEFT | AOUT_CHAN_MIDDLERIGHT |
 261          AOUT_CHAN_REARLEFT | AOUT_CHAN_REARRIGHT) &&
 262         p_filter->fmt_in.audio.i_physical_channels !=
 263         (AOUT_CHAN_LEFT | AOUT_CHAN_RIGHT) )
 264     {
 265         return -1;
 266     }
 267
 268     p_filter->pf_audio_filter = Filter;
 269
 270     return 0;
 271 }
 272
 273 /*****************************************************************************
 274  * Filter:
 275  *****************************************************************************/
 276 static block_t *Filter( filter_t *p_filter, block_t *p_block )
 277 {
 278     aout_filter_t aout_filter;
 279     aout_buffer_t in_buf, out_buf;
 280     block_t *p_out;
 281     int i_out_size;
 282
 283     if( !p_block || !p_block->i_samples )
 284     {
 285         if( p_block ) p_block->pf_release( p_block );
 286         return NULL;
 287     }
 288
 289     i_out_size = p_block->i_samples *
 290       p_filter->fmt_out.audio.i_bitspersample *
 291         p_filter->fmt_out.audio.i_channels / 8;
 292
 293     p_out = p_filter->pf_audio_buffer_new( p_filter, i_out_size );
 294     if( !p_out )
 295     {
 296         msg_Warn( p_filter, "can't get output buffer" );
 297         p_block->pf_release( p_block );
 298         return NULL;
 299     }
 300
 301     p_out->i_samples = p_block->i_samples;
 302     p_out->i_dts = p_block->i_dts;
 303     p_out->i_pts = p_block->i_pts;
 304     p_out->i_length = p_block->i_length;
 305
 306     aout_filter.p_sys = (struct aout_filter_sys_t *)p_filter->p_sys;
 307     aout_filter.input = p_filter->fmt_in.audio;
 308     aout_filter.input.i_format = p_filter->fmt_in.i_codec;
 309     aout_filter.output = p_filter->fmt_out.audio;
 310     aout_filter.output.i_format = p_filter->fmt_out.i_codec;
 311
 312     in_buf.p_buffer = p_block->p_buffer;
 313     in_buf.i_nb_bytes = p_block->i_buffer;
 314     in_buf.i_nb_samples = p_block->i_samples;
 315     out_buf.p_buffer = p_out->p_buffer;
 316     out_buf.i_nb_bytes = p_out->i_buffer;
 317     out_buf.i_nb_samples = p_out->i_samples;
 318
 319     DoWork( (aout_instance_t *)p_filter, &aout_filter, &in_buf, &out_buf );
 320
 321     p_block->pf_release( p_block );
 322
 323     p_out->i_buffer = out_buf.i_nb_bytes;
 324     p_out->i_samples = out_buf.i_nb_samples;
 325
 326     return p_out;
 327 }
 328