git.sesse.net Git - vlc/blob - modules/audio_filter/converter/a52tofloat32.c

   1 /*****************************************************************************
   2  * a52tofloat32.c: ATSC A/52 aka AC-3 decoder plugin for VLC.
   3  *   This plugin makes use of liba52 to decode A/52 audio
   4  *   (http://liba52.sf.net/).
   5  *****************************************************************************
   6  * Copyright (C) 2001-2009 the VideoLAN team
   7  * $Id$
   8  *
   9  * Authors: Gildas Bazin <gbazin@videolan.org>
  10  *          Christophe Massiot <massiot@via.ecp.fr>
  11  *
  12  * This program is free software; you can redistribute it and/or modify
  13  * it under the terms of the GNU General Public License as published by
  14  * the Free Software Foundation; either version 2 of the License, or
  15  * (at your option) any later version.
  16  *
  17  * This program is distributed in the hope that it will be useful,
  18  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  19  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  20  * GNU General Public License for more details.
  21  *
  22  * You should have received a copy of the GNU General Public License
  23  * along with this program; if not, write to the Free Software
  24  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301, USA.
  25  *****************************************************************************/
  26
  27 /*****************************************************************************
  28  * Preamble
  29  *****************************************************************************/
  30 #ifdef HAVE_CONFIG_H
  31 # include "config.h"
  32 #endif
  33
  34 #include <vlc_common.h>
  35 #include <vlc_plugin.h>
  36
  37 #include <stdint.h>                                         /* int16_t .. */
  38
  39 #ifdef USE_A52DEC_TREE                                 /* liba52 header file */
  40 #   include "include/a52.h"
  41 #else
  42 #   include "a52dec/a52.h"
  43 #endif
  44
  45 #include <vlc_aout.h>
  46 #include <vlc_block.h>
  47 #include <vlc_filter.h>
  48
  49 /*****************************************************************************
  50  * Local prototypes
  51  *****************************************************************************/
  52 static int  OpenFilter ( vlc_object_t * );
  53 static void CloseFilter( vlc_object_t * );
  54 static block_t *Convert( filter_t *, block_t * );
  55
  56 /* liba52 channel order */
  57 static const uint32_t pi_channels_in[] =
  58 { AOUT_CHAN_LFE, AOUT_CHAN_LEFT, AOUT_CHAN_CENTER, AOUT_CHAN_RIGHT,
  59   AOUT_CHAN_REARLEFT, AOUT_CHAN_REARCENTER, AOUT_CHAN_REARRIGHT, 0 };
  60
  61 /*****************************************************************************
  62  * Local structures
  63  *****************************************************************************/
  64 struct filter_sys_t
  65 {
  66     a52_state_t * p_liba52; /* liba52 internal structure */
  67     bool b_dynrng; /* see below */
  68     int i_flags; /* liba52 flags, see a52dec/doc/liba52.txt */
  69     bool b_dontwarn;
  70     int i_nb_channels; /* number of float32 per sample */
  71
  72     int pi_chan_table[AOUT_CHAN_MAX]; /* channel reordering */
  73 };
  74
  75 /*****************************************************************************
  76  * Module descriptor
  77  *****************************************************************************/
  78 #define DYNRNG_TEXT N_("A/52 dynamic range compression")
  79 #define DYNRNG_LONGTEXT N_( \
  80     "Dynamic range compression makes the loud sounds softer, and the soft " \
  81     "sounds louder, so you can more easily listen to the stream in a noisy " \
  82     "environment without disturbing anyone. If you disable the dynamic range "\
  83     "compression the playback will be more adapted to a movie theater or a " \
  84     "listening room.")
  85 #define UPMIX_TEXT N_("Enable internal upmixing")
  86 #define UPMIX_LONGTEXT N_( \
  87     "Enable the internal upmixing algorithm (not recommended).")
  88
  89 vlc_module_begin ()
  90     set_shortname( "A/52" )
  91     set_description( N_("ATSC A/52 (AC-3) audio decoder") )
  92     set_category( CAT_INPUT )
  93     set_subcategory( SUBCAT_INPUT_ACODEC )
  94     add_bool( "a52-dynrng", true, NULL, DYNRNG_TEXT, DYNRNG_LONGTEXT, false )
  95     add_bool( "a52-upmix", false, NULL, UPMIX_TEXT, UPMIX_LONGTEXT, true )
  96     set_capability( "audio filter2", 100 )
  97     set_callbacks( OpenFilter, CloseFilter )
  98 vlc_module_end ()
  99
 100 /*****************************************************************************
 101  * Open:
 102  *****************************************************************************/
 103 static int Open( vlc_object_t *p_this, filter_sys_t *p_sys,
 104                  audio_format_t input, audio_format_t output )
 105 {
 106     p_sys->b_dynrng = config_GetInt( p_this, "a52-dynrng" );
 107     p_sys->b_dontwarn = 0;
 108
 109     /* No upmixing: it's not necessary and some other filters may want to do
 110      * it themselves. */
 111     if ( aout_FormatNbChannels( &output ) > aout_FormatNbChannels( &input ) )
 112     {
 113         if ( ! config_GetInt( p_this, "a52-upmix" ) )
 114         {
 115             return VLC_EGENERIC;
 116         }
 117     }
 118
 119     /* We'll do our own downmixing, thanks. */
 120     p_sys->i_nb_channels = aout_FormatNbChannels( &output );
 121     switch ( (output.i_physical_channels & AOUT_CHAN_PHYSMASK)
 122               & ~AOUT_CHAN_LFE )
 123     {
 124     case AOUT_CHAN_CENTER:
 125         if ( (output.i_original_channels & AOUT_CHAN_CENTER)
 126               || (output.i_original_channels
 127                    & (AOUT_CHAN_LEFT | AOUT_CHAN_RIGHT)) )
 128         {
 129             p_sys->i_flags = A52_MONO;
 130         }
 131         else if ( output.i_original_channels & AOUT_CHAN_LEFT )
 132         {
 133             p_sys->i_flags = A52_CHANNEL1;
 134         }
 135         else
 136         {
 137             p_sys->i_flags = A52_CHANNEL2;
 138         }
 139         break;
 140
 141     case AOUT_CHAN_LEFT | AOUT_CHAN_RIGHT:
 142         if ( output.i_original_channels & AOUT_CHAN_DOLBYSTEREO )
 143         {
 144             p_sys->i_flags = A52_DOLBY;
 145         }
 146         else if ( input.i_original_channels == AOUT_CHAN_CENTER )
 147         {
 148             p_sys->i_flags = A52_MONO;
 149         }
 150         else if ( input.i_original_channels & AOUT_CHAN_DUALMONO )
 151         {
 152             p_sys->i_flags = A52_CHANNEL;
 153         }
 154         else if ( !(output.i_original_channels & AOUT_CHAN_RIGHT) )
 155         {
 156             p_sys->i_flags = A52_CHANNEL1;
 157         }
 158         else if ( !(output.i_original_channels & AOUT_CHAN_LEFT) )
 159         {
 160             p_sys->i_flags = A52_CHANNEL2;
 161         }
 162         else
 163         {
 164             p_sys->i_flags = A52_STEREO;
 165         }
 166         break;
 167
 168     case AOUT_CHAN_LEFT | AOUT_CHAN_RIGHT | AOUT_CHAN_CENTER:
 169         p_sys->i_flags = A52_3F;
 170         break;
 171
 172     case AOUT_CHAN_LEFT | AOUT_CHAN_RIGHT | AOUT_CHAN_REARCENTER:
 173         p_sys->i_flags = A52_2F1R;
 174         break;
 175
 176     case AOUT_CHAN_LEFT | AOUT_CHAN_RIGHT | AOUT_CHAN_CENTER
 177           | AOUT_CHAN_REARCENTER:
 178         p_sys->i_flags = A52_3F1R;
 179         break;
 180
 181     case AOUT_CHAN_LEFT | AOUT_CHAN_RIGHT
 182           | AOUT_CHAN_REARLEFT | AOUT_CHAN_REARRIGHT:
 183         p_sys->i_flags = A52_2F2R;
 184         break;
 185
 186     case AOUT_CHAN_LEFT | AOUT_CHAN_RIGHT | AOUT_CHAN_CENTER
 187           | AOUT_CHAN_REARLEFT | AOUT_CHAN_REARRIGHT:
 188         p_sys->i_flags = A52_3F2R;
 189         break;
 190
 191     default:
 192         msg_Warn( p_this, "unknown sample format!" );
 193         free( p_sys );
 194         return VLC_EGENERIC;
 195     }
 196     if ( output.i_physical_channels & AOUT_CHAN_LFE )
 197     {
 198         p_sys->i_flags |= A52_LFE;
 199     }
 200     p_sys->i_flags |= A52_ADJUST_LEVEL;
 201
 202     /* Initialize liba52 */
 203     p_sys->p_liba52 = a52_init( 0 );
 204     if( p_sys->p_liba52 == NULL )
 205     {
 206         msg_Err( p_this, "unable to initialize liba52" );
 207         free( p_sys );
 208         return VLC_EGENERIC;
 209     }
 210
 211     aout_CheckChannelReorder( pi_channels_in, NULL,
 212                               output.i_physical_channels & AOUT_CHAN_PHYSMASK,
 213                               p_sys->i_nb_channels,
 214                               p_sys->pi_chan_table );
 215
 216     return VLC_SUCCESS;
 217 }
 218
 219 /*****************************************************************************
 220  * Interleave: helper function to interleave channels
 221  *****************************************************************************/
 222 static void Interleave( sample_t * p_out, const sample_t * p_in,
 223                         int i_nb_channels, int *pi_chan_table )
 224 {
 225     /* We do not only have to interleave, but also reorder the channels */
 226
 227     int i, j;
 228     for ( j = 0; j < i_nb_channels; j++ )
 229     {
 230         for ( i = 0; i < 256; i++ )
 231         {
 232             p_out[i * i_nb_channels + pi_chan_table[j]] = p_in[j * 256 + i];
 233         }
 234     }
 235 }
 236
 237 /*****************************************************************************
 238  * Duplicate: helper function to duplicate a unique channel
 239  *****************************************************************************/
 240 static void Duplicate( sample_t * p_out, const sample_t * p_in )
 241 {
 242     int i;
 243
 244     for ( i = 256; i--; )
 245     {
 246         *p_out++ = *p_in;
 247         *p_out++ = *p_in;
 248         p_in++;
 249     }
 250 }
 251
 252 /*****************************************************************************
 253  * Exchange: helper function to exchange left & right channels
 254  *****************************************************************************/
 255 static void Exchange( sample_t * p_out, const sample_t * p_in )
 256 {
 257     int i;
 258     const sample_t * p_first = p_in + 256;
 259     const sample_t * p_second = p_in;
 260
 261     for ( i = 0; i < 256; i++ )
 262     {
 263         *p_out++ = *p_first++;
 264         *p_out++ = *p_second++;
 265     }
 266 }
 267
 268 /*****************************************************************************
 269  * DoWork: decode an ATSC A/52 frame.
 270  *****************************************************************************/
 271 static void DoWork( filter_t * p_filter,
 272                     aout_buffer_t * p_in_buf, aout_buffer_t * p_out_buf )
 273 {
 274     filter_sys_t    *p_sys = p_filter->p_sys;
 275 #ifdef LIBA52_FIXED
 276     sample_t        i_sample_level = (1 << 24);
 277 #else
 278     sample_t        i_sample_level = 1;
 279 #endif
 280     int             i_flags = p_sys->i_flags;
 281     int             i_bytes_per_block = 256 * p_sys->i_nb_channels
 282                       * sizeof(sample_t);
 283     int             i;
 284
 285     /* Do the actual decoding now. */
 286     a52_frame( p_sys->p_liba52, p_in_buf->p_buffer,
 287                &i_flags, &i_sample_level, 0 );
 288
 289     if ( (i_flags & A52_CHANNEL_MASK) != (p_sys->i_flags & A52_CHANNEL_MASK)
 290           && !p_sys->b_dontwarn )
 291     {
 292         msg_Warn( p_filter,
 293                   "liba52 couldn't do the requested downmix 0x%x->0x%x",
 294                   p_sys->i_flags  & A52_CHANNEL_MASK,
 295                   i_flags & A52_CHANNEL_MASK );
 296
 297         p_sys->b_dontwarn = 1;
 298     }
 299
 300     if( !p_sys->b_dynrng )
 301     {
 302         a52_dynrng( p_sys->p_liba52, NULL, NULL );
 303     }
 304
 305     for ( i = 0; i < 6; i++ )
 306     {
 307         sample_t * p_samples;
 308
 309         if( a52_block( p_sys->p_liba52 ) )
 310         {
 311             msg_Warn( p_filter, "a52_block failed for block %d", i );
 312         }
 313
 314         p_samples = a52_samples( p_sys->p_liba52 );
 315
 316         if ( ((p_sys->i_flags & A52_CHANNEL_MASK) == A52_CHANNEL1
 317                || (p_sys->i_flags & A52_CHANNEL_MASK) == A52_CHANNEL2
 318                || (p_sys->i_flags & A52_CHANNEL_MASK) == A52_MONO)
 319               && (p_filter->fmt_out.audio.i_physical_channels
 320                    & (AOUT_CHAN_LEFT | AOUT_CHAN_RIGHT)) )
 321         {
 322             Duplicate( (sample_t *)(p_out_buf->p_buffer + i * i_bytes_per_block),
 323                        p_samples );
 324         }
 325         else if ( p_filter->fmt_out.audio.i_original_channels
 326                     & AOUT_CHAN_REVERSESTEREO )
 327         {
 328             Exchange( (sample_t *)(p_out_buf->p_buffer + i * i_bytes_per_block),
 329                       p_samples );
 330         }
 331         else
 332         {
 333             /* Interleave the *$£%ù samples. */
 334             Interleave( (sample_t *)(p_out_buf->p_buffer + i * i_bytes_per_block),
 335                         p_samples, p_sys->i_nb_channels, p_sys->pi_chan_table);
 336         }
 337     }
 338
 339     p_out_buf->i_nb_samples = p_in_buf->i_nb_samples;
 340     p_out_buf->i_buffer = i_bytes_per_block * 6;
 341 }
 342
 343 /*****************************************************************************
 344  * OpenFilter:
 345  *****************************************************************************/
 346 static int OpenFilter( vlc_object_t *p_this )
 347 {
 348     filter_t *p_filter = (filter_t *)p_this;
 349     filter_sys_t *p_sys;
 350     int i_ret;
 351
 352     if( p_filter->fmt_in.i_codec != VLC_CODEC_A52  )
 353     {
 354         return VLC_EGENERIC;
 355     }
 356
 357     p_filter->fmt_out.audio.i_format =
 358 #ifdef LIBA52_FIXED
 359         p_filter->fmt_out.i_codec = VLC_CODEC_FI32;
 360 #else
 361         p_filter->fmt_out.i_codec = VLC_CODEC_FL32;
 362 #endif
 363     p_filter->fmt_out.audio.i_bitspersample =
 364         aout_BitsPerSample( p_filter->fmt_out.i_codec );
 365
 366     /* Allocate the memory needed to store the module's structure */
 367     p_filter->p_sys = p_sys = malloc( sizeof(filter_sys_t) );
 368     if( p_sys == NULL )
 369         return VLC_ENOMEM;
 370
 371     i_ret = Open( VLC_OBJECT(p_filter), p_sys,
 372                   p_filter->fmt_in.audio, p_filter->fmt_out.audio );
 373
 374     p_filter->pf_audio_filter = Convert;
 375     p_filter->fmt_out.audio.i_rate = p_filter->fmt_in.audio.i_rate;
 376
 377     return i_ret;
 378 }
 379
 380 /*****************************************************************************
 381  * CloseFilter : deallocate data structures
 382  *****************************************************************************/
 383 static void CloseFilter( vlc_object_t *p_this )
 384 {
 385     filter_t *p_filter = (filter_t *)p_this;
 386     filter_sys_t *p_sys = p_filter->p_sys;
 387
 388     a52_free( p_sys->p_liba52 );
 389     free( p_sys );
 390 }
 391
 392 static block_t *Convert( filter_t *p_filter, block_t *p_block )
 393 {
 394     if( !p_block || !p_block->i_nb_samples )
 395     {
 396         if( p_block )
 397             block_Release( p_block );
 398         return NULL;
 399     }
 400
 401     size_t i_out_size = p_block->i_nb_samples *
 402       p_filter->fmt_out.audio.i_bitspersample *
 403         p_filter->fmt_out.audio.i_channels / 8;
 404
 405     block_t *p_out = filter_NewAudioBuffer( p_filter, i_out_size );
 406     if( !p_out )
 407     {
 408         msg_Warn( p_filter, "can't get output buffer" );
 409         block_Release( p_block );
 410         return NULL;
 411     }
 412
 413     p_out->i_nb_samples = p_block->i_nb_samples;
 414     p_out->i_dts = p_block->i_dts;
 415     p_out->i_pts = p_block->i_pts;
 416     p_out->i_length = p_block->i_length;
 417
 418     DoWork( p_filter, p_block, p_out );
 419
 420     block_Release( p_block );
 421
 422     return p_out;
 423 }