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 #include <vlc/vlc.h>
  28 #include <vlc_aout.h>
  29 #include <vlc_filter.h>
  30 #include <vlc_block.h>
  31
  32 /*****************************************************************************
  33  * Local prototypes
  34  *****************************************************************************/
  35 static int  Create    ( vlc_object_t * );
  36
  37 static void DoWork    ( aout_instance_t *, aout_filter_t *, aout_buffer_t *,
  38                         aout_buffer_t * );
  39
  40 static int  OpenFilter ( vlc_object_t * );
  41 static block_t *Filter( filter_t *, block_t * );
  42
  43 /*****************************************************************************
  44  * Module descriptor
  45  *****************************************************************************/
  46 vlc_module_begin();
  47     set_description( _("Audio filter for simple channel mixing") );
  48     set_capability( "audio filter", 10 );
  49     set_category( CAT_AUDIO );
  50     set_subcategory( SUBCAT_AUDIO_MISC );
  51     set_callbacks( Create, NULL );
  52
  53     add_submodule();
  54     set_description( _("audio filter for simple channel mixing") );
  55     set_capability( "audio filter2", 10 );
  56     set_callbacks( OpenFilter, NULL );
  57 vlc_module_end();
  58
  59 /*****************************************************************************
  60  * Create: allocate trivial channel mixer
  61  *****************************************************************************/
  62 static int Create( vlc_object_t *p_this )
  63 {
  64     aout_filter_t * p_filter = (aout_filter_t *)p_this;
  65
  66     if ( (p_filter->input.i_physical_channels
  67            == p_filter->output.i_physical_channels
  68            && p_filter->input.i_original_channels
  69                == p_filter->output.i_original_channels)
  70           || p_filter->input.i_format != p_filter->output.i_format
  71           || p_filter->input.i_rate != p_filter->output.i_rate
  72           || p_filter->input.i_format != VLC_FOURCC('f','l','3','2') )
  73     {
  74         return -1;
  75     }
  76
  77     /* Only conversion to Mono, Stereo and 4.0 right now */
  78     if( p_filter->output.i_physical_channels !=
  79         (AOUT_CHAN_LEFT | AOUT_CHAN_RIGHT)
  80         && p_filter->output.i_physical_channels !=
  81         ( AOUT_CHAN_LEFT | AOUT_CHAN_RIGHT |
  82         AOUT_CHAN_REARLEFT | AOUT_CHAN_REARRIGHT)
  83         && p_filter->output.i_physical_channels != AOUT_CHAN_CENTER )
  84     {
  85         return -1;
  86     }
  87
  88     /* Only from 7/7.1/5/5.1/2.0 */
  89     if( (p_filter->input.i_physical_channels & ~AOUT_CHAN_LFE) !=
  90         (AOUT_CHAN_LEFT | AOUT_CHAN_RIGHT | AOUT_CHAN_CENTER |
  91          AOUT_CHAN_REARLEFT | AOUT_CHAN_REARRIGHT) &&
  92         (p_filter->input.i_physical_channels & ~AOUT_CHAN_LFE) !=
  93         (AOUT_CHAN_LEFT | AOUT_CHAN_RIGHT | AOUT_CHAN_CENTER |
  94          AOUT_CHAN_MIDDLELEFT | AOUT_CHAN_MIDDLERIGHT |
  95          AOUT_CHAN_REARLEFT | AOUT_CHAN_REARRIGHT) &&
  96         p_filter->input.i_physical_channels !=
  97         (AOUT_CHAN_LEFT | AOUT_CHAN_RIGHT) )
  98     {
  99         return -1;
 100     }
 101
 102     p_filter->pf_do_work = DoWork;
 103     p_filter->b_in_place = 0;
 104
 105     return 0;
 106 }
 107
 108 /*****************************************************************************
 109  * DoWork: convert a buffer
 110  *****************************************************************************/
 111 static void DoWork( aout_instance_t * p_aout, aout_filter_t * p_filter,
 112                     aout_buffer_t * p_in_buf, aout_buffer_t * p_out_buf )
 113 {
 114     int i_input_nb = aout_FormatNbChannels( &p_filter->input );
 115     int i_output_nb = aout_FormatNbChannels( &p_filter->output );
 116     float *p_dest = (float *)p_out_buf->p_buffer;
 117     float *p_src = (float *)p_in_buf->p_buffer;
 118     int i;
 119
 120     p_out_buf->i_nb_samples = p_in_buf->i_nb_samples;
 121     p_out_buf->i_nb_bytes = p_in_buf->i_nb_bytes * i_output_nb / i_input_nb;
 122
 123     if( p_filter->output.i_physical_channels ==
 124                             (AOUT_CHAN_LEFT | AOUT_CHAN_RIGHT) )
 125     {
 126         if( p_filter->input.i_physical_channels & AOUT_CHAN_MIDDLELEFT )
 127         for( i = p_in_buf->i_nb_samples; i--; )
 128         {
 129             *p_dest = p_src[6] + 0.5 * p_src[0] + p_src[2] / 4 + p_src[4] / 4;
 130             p_dest++;
 131             *p_dest = p_src[6] + 0.5 * p_src[1] + p_src[3] / 4 + p_src[5] / 4;
 132             p_dest++;
 133
 134             p_src += 7;
 135
 136             if( p_filter->input.i_physical_channels & AOUT_CHAN_LFE ) p_src++;
 137         }
 138         else
 139         for( i = p_in_buf->i_nb_samples; i--; )
 140         {
 141             *p_dest = p_src[4] + 0.5 * p_src[0] + 0.33 * p_src[2];
 142             p_dest++;
 143             *p_dest = p_src[4] + 0.5 * p_src[1] + 0.33 * p_src[3];
 144             p_dest++;
 145
 146             p_src += 5;
 147
 148             if( p_filter->input.i_physical_channels & AOUT_CHAN_LFE ) p_src++;
 149         }
 150     }
 151     else if( p_filter->output.i_physical_channels == AOUT_CHAN_CENTER )
 152     {
 153         if( p_filter->input.i_physical_channels & AOUT_CHAN_MIDDLELEFT )
 154         for( i = p_in_buf->i_nb_samples; i--; )
 155         {
 156             *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;
 157             p_dest++;
 158
 159             p_src += 7;
 160
 161             if( p_filter->input.i_physical_channels & AOUT_CHAN_LFE ) p_src++;
 162         }
 163         else if( p_filter->input.i_physical_channels & AOUT_CHAN_REARLEFT )
 164         for( i = p_in_buf->i_nb_samples; i--; )
 165         {
 166             *p_dest = p_src[4] + p_src[0] / 4 + p_src[1] / 4 + p_src[2] / 6 + p_src[3] / 6;
 167             p_dest++;
 168
 169             p_src += 5;
 170
 171             if( p_filter->input.i_physical_channels & AOUT_CHAN_LFE ) p_src++;
 172         }
 173         else
 174         for( i = p_in_buf->i_nb_samples; i--; )
 175         {
 176             *p_dest = p_src[0] / 2 + p_src[1] / 2;
 177             p_dest++;
 178
 179             p_src += 2;
 180         }
 181     }
 182     else
 183     {
 184         if( p_filter->input.i_physical_channels & AOUT_CHAN_MIDDLELEFT )
 185         for( i = p_in_buf->i_nb_samples; i--; )
 186         {
 187             *p_dest = p_src[6] + 0.5 * p_src[0] + p_src[2] / 6;
 188             p_dest++;
 189             *p_dest = p_src[6] + 0.5 * p_src[1] + p_src[3] / 6;
 190             p_dest++;
 191             *p_dest = p_src[2] / 6 +  p_src[4];
 192             p_dest++;
 193             *p_dest = p_src[3] / 6 +  p_src[5];
 194             p_dest++;
 195
 196             p_src += 7;
 197
 198             if( p_filter->input.i_physical_channels & AOUT_CHAN_LFE ) p_src++;
 199         }
 200         else
 201         for( i = p_in_buf->i_nb_samples; i--; )
 202         {
 203             *p_dest = p_src[4] + 0.5 * p_src[0];
 204             p_dest++;
 205             *p_dest = p_src[4] + 0.5 * p_src[1];
 206             p_dest++;
 207             *p_dest = p_src[2];
 208             p_dest++;
 209             *p_dest = p_src[3];
 210             p_dest++;
 211
 212             p_src += 5;
 213
 214             if( p_filter->input.i_physical_channels & AOUT_CHAN_LFE ) p_src++;
 215         }
 216
 217     }
 218 }
 219
 220 /*****************************************************************************
 221  * OpenFilter:
 222  *****************************************************************************/
 223 static int OpenFilter( vlc_object_t *p_this )
 224 {
 225     filter_t *p_filter = (filter_t *)p_this;
 226
 227     if ( (p_filter->fmt_in.audio.i_physical_channels
 228            == p_filter->fmt_out.audio.i_physical_channels
 229            && p_filter->fmt_in.audio.i_original_channels
 230                == p_filter->fmt_out.audio.i_original_channels)
 231           || p_filter->fmt_in.i_codec != p_filter->fmt_out.i_codec
 232           || p_filter->fmt_in.audio.i_rate != p_filter->fmt_out.audio.i_rate
 233           || p_filter->fmt_in.i_codec != VLC_FOURCC('f','l','3','2') )
 234     {
 235         return -1;
 236     }
 237
 238     /* Only conversion to Mono, Stereo and 4.0 right now */
 239     if( p_filter->fmt_out.audio.i_physical_channels !=
 240         (AOUT_CHAN_LEFT | AOUT_CHAN_RIGHT)
 241         && p_filter->fmt_out.audio.i_physical_channels !=
 242         ( AOUT_CHAN_LEFT | AOUT_CHAN_RIGHT |
 243         AOUT_CHAN_REARLEFT | AOUT_CHAN_REARRIGHT)
 244         && p_filter->fmt_out.audio.i_physical_channels != AOUT_CHAN_CENTER )
 245     {
 246         return -1;
 247     }
 248
 249     /* Only from 7/7.1/5/5.1/2.0 */
 250     if( (p_filter->fmt_in.audio.i_physical_channels & ~AOUT_CHAN_LFE) !=
 251         (AOUT_CHAN_LEFT | AOUT_CHAN_RIGHT | AOUT_CHAN_CENTER |
 252          AOUT_CHAN_REARLEFT | AOUT_CHAN_REARRIGHT) &&
 253         (p_filter->fmt_in.audio.i_physical_channels & ~AOUT_CHAN_LFE) !=
 254         (AOUT_CHAN_LEFT | AOUT_CHAN_RIGHT | AOUT_CHAN_CENTER |
 255          AOUT_CHAN_MIDDLELEFT | AOUT_CHAN_MIDDLERIGHT |
 256          AOUT_CHAN_REARLEFT | AOUT_CHAN_REARRIGHT) &&
 257         p_filter->fmt_in.audio.i_physical_channels !=
 258         (AOUT_CHAN_LEFT | AOUT_CHAN_RIGHT) )
 259     {
 260         return -1;
 261     }
 262
 263     p_filter->pf_audio_filter = Filter;
 264
 265     return 0;
 266 }
 267
 268 /*****************************************************************************
 269  * Filter:
 270  *****************************************************************************/
 271 static block_t *Filter( filter_t *p_filter, block_t *p_block )
 272 {
 273     aout_filter_t aout_filter;
 274     aout_buffer_t in_buf, out_buf;
 275     block_t *p_out;
 276     int i_out_size;
 277
 278     if( !p_block || !p_block->i_samples )
 279     {
 280         if( p_block ) p_block->pf_release( p_block );
 281         return NULL;
 282     }
 283
 284     i_out_size = p_block->i_samples *
 285       p_filter->fmt_out.audio.i_bitspersample *
 286         p_filter->fmt_out.audio.i_channels / 8;
 287
 288     p_out = p_filter->pf_audio_buffer_new( p_filter, i_out_size );
 289     if( !p_out )
 290     {
 291         msg_Warn( p_filter, "can't get output buffer" );
 292         p_block->pf_release( p_block );
 293         return NULL;
 294     }
 295
 296     p_out->i_samples = p_block->i_samples;
 297     p_out->i_dts = p_block->i_dts;
 298     p_out->i_pts = p_block->i_pts;
 299     p_out->i_length = p_block->i_length;
 300
 301     aout_filter.p_sys = (struct aout_filter_sys_t *)p_filter->p_sys;
 302     aout_filter.input = p_filter->fmt_in.audio;
 303     aout_filter.input.i_format = p_filter->fmt_in.i_codec;
 304     aout_filter.output = p_filter->fmt_out.audio;
 305     aout_filter.output.i_format = p_filter->fmt_out.i_codec;
 306
 307     in_buf.p_buffer = p_block->p_buffer;
 308     in_buf.i_nb_bytes = p_block->i_buffer;
 309     in_buf.i_nb_samples = p_block->i_samples;
 310     out_buf.p_buffer = p_out->p_buffer;
 311     out_buf.i_nb_bytes = p_out->i_buffer;
 312     out_buf.i_nb_samples = p_out->i_samples;
 313
 314     DoWork( (aout_instance_t *)p_filter, &aout_filter, &in_buf, &out_buf );
 315
 316     p_block->pf_release( p_block );
 317
 318     p_out->i_buffer = out_buf.i_nb_bytes;
 319     p_out->i_samples = out_buf.i_nb_samples;
 320
 321     return p_out;
 322 }
 323