git.sesse.net Git - vlc/blob - modules/demux/mpeg/es.c

   1 /*****************************************************************************
   2  * es.c : Generic audio ES input module for vlc
   3  *****************************************************************************
   4  * Copyright (C) 2001-2008 VLC authors and VideoLAN
   5  * $Id$
   6  *
   7  * Authors: Laurent Aimar <fenrir@via.ecp.fr>
   8  *          Gildas Bazin <gbazin@videolan.org>
   9  *
  10  * This program is free software; you can redistribute it and/or modify it
  11  * under the terms of the GNU Lesser General Public License as published by
  12  * the Free Software Foundation; either version 2.1 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 Lesser General Public License for more details.
  19  *
  20  * You should have received a copy of the GNU Lesser General Public License
  21  * along with this program; if not, write to the Free Software Foundation,
  22  * Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301, USA.
  23  *****************************************************************************/
  24
  25 /*****************************************************************************
  26  * Preamble
  27  *****************************************************************************/
  28
  29 #ifdef HAVE_CONFIG_H
  30 # include "config.h"
  31 #endif
  32
  33 #include <vlc_common.h>
  34 #include <vlc_plugin.h>
  35 #include <vlc_demux.h>
  36 #include <vlc_codec.h>
  37 #include <vlc_codecs.h>
  38 #include <vlc_input.h>
  39
  40 #include "../../codec/a52.h"
  41 #include "../../codec/dts_header.h"
  42
  43 /*****************************************************************************
  44  * Module descriptor
  45  *****************************************************************************/
  46 static int  OpenAudio( vlc_object_t * );
  47 static int  OpenVideo( vlc_object_t * );
  48 static void Close    ( vlc_object_t * );
  49
  50 #define FPS_TEXT N_("Frames per Second")
  51 #define FPS_LONGTEXT N_("This is the frame rate used as a fallback when " \
  52     "playing MPEG video elementary streams.")
  53
  54 vlc_module_begin ()
  55     set_category( CAT_INPUT )
  56     set_subcategory( SUBCAT_INPUT_DEMUX )
  57     set_description( N_("MPEG-I/II/4 / A52 / DTS / MLP audio" ) )
  58     set_shortname( N_("Audio ES") )
  59     set_capability( "demux", 155 )
  60     set_callbacks( OpenAudio, Close )
  61
  62     add_shortcut( "mpga", "mp3",
  63                   "m4a", "mp4a", "aac",
  64                   "ac3", "a52",
  65                   "eac3",
  66                   "dts",
  67                   "mlp", "thd" )
  68
  69     add_submodule()
  70     set_description( N_("MPEG-4 video" ) )
  71     set_capability( "demux", 0 )
  72     set_callbacks( OpenVideo, Close )
  73     add_float( "es-fps", 25, FPS_TEXT, FPS_LONGTEXT, false )
  74
  75     add_shortcut( "m4v" )
  76     add_shortcut( "mp4v" )
  77 vlc_module_end ()
  78
  79 /*****************************************************************************
  80  * Local prototypes
  81  *****************************************************************************/
  82 static int Demux  ( demux_t * );
  83 static int Control( demux_t *, int, va_list );
  84
  85 typedef struct
  86 {
  87     vlc_fourcc_t i_codec;
  88     bool       b_use_word;
  89     const char *psz_name;
  90     int  (*pf_probe)( demux_t *p_demux, int64_t *pi_offset );
  91     int  (*pf_init)( demux_t *p_demux );
  92 } codec_t;
  93
  94 struct demux_sys_t
  95 {
  96     codec_t codec;
  97
  98     es_out_id_t *p_es;
  99
 100     bool  b_start;
 101     decoder_t   *p_packetizer;
 102     block_t     *p_packetized_data;
 103
 104     mtime_t     i_pts;
 105     mtime_t     i_time_offset;
 106     int64_t     i_bytes;
 107
 108     bool        b_big_endian;
 109     bool        b_estimate_bitrate;
 110     int         i_bitrate_avg;  /* extracted from Xing header */
 111
 112     bool b_initial_sync_failed;
 113
 114     int i_packet_size;
 115
 116     int64_t i_stream_offset;
 117
 118     float   f_fps;
 119
 120     /* Mpga specific */
 121     struct
 122     {
 123         int i_frames;
 124         int i_bytes;
 125         int i_bitrate_avg;
 126         int i_frame_samples;
 127     } xing;
 128 };
 129
 130 static int MpgaProbe( demux_t *p_demux, int64_t *pi_offset );
 131 static int MpgaInit( demux_t *p_demux );
 132
 133 static int AacProbe( demux_t *p_demux, int64_t *pi_offset );
 134 static int AacInit( demux_t *p_demux );
 135
 136 static int EA52Probe( demux_t *p_demux, int64_t *pi_offset );
 137 static int A52Probe( demux_t *p_demux, int64_t *pi_offset );
 138 static int A52Init( demux_t *p_demux );
 139
 140 static int DtsProbe( demux_t *p_demux, int64_t *pi_offset );
 141 static int DtsInit( demux_t *p_demux );
 142
 143 static int MlpProbe( demux_t *p_demux, int64_t *pi_offset );
 144 static int MlpInit( demux_t *p_demux );
 145
 146 static bool Parse( demux_t *p_demux, block_t **pp_output );
 147
 148 static const codec_t p_codecs[] = {
 149     { VLC_CODEC_MP4A, false, "mp4 audio",  AacProbe,  AacInit },
 150     { VLC_CODEC_MPGA, false, "mpeg audio", MpgaProbe, MpgaInit },
 151     { VLC_CODEC_A52, true,  "a52 audio",  A52Probe,  A52Init },
 152     { VLC_CODEC_EAC3, true,  "eac3 audio", EA52Probe, A52Init },
 153     { VLC_CODEC_DTS, false, "dts audio",  DtsProbe,  DtsInit },
 154     { VLC_CODEC_TRUEHD, false, "mlp audio",  MlpProbe,  MlpInit },
 155
 156     { 0, false, NULL, NULL, NULL }
 157 };
 158
 159 static int VideoInit( demux_t *p_demux );
 160
 161 static const codec_t codec_m4v = {
 162     VLC_CODEC_MP4V, false, "mp4 video", NULL,  VideoInit
 163 };
 164
 165 /*****************************************************************************
 166  * OpenCommon: initializes demux structures
 167  *****************************************************************************/
 168 static int OpenCommon( demux_t *p_demux,
 169                        int i_cat, const codec_t *p_codec, int64_t i_bs_offset )
 170 {
 171     demux_sys_t *p_sys;
 172
 173     es_format_t fmt;
 174
 175     DEMUX_INIT_COMMON(); p_sys = p_demux->p_sys;
 176     memset( p_sys, 0, sizeof( demux_sys_t ) );
 177     p_sys->codec = *p_codec;
 178     p_sys->p_es = NULL;
 179     p_sys->b_start = true;
 180     p_sys->i_stream_offset = i_bs_offset;
 181     p_sys->b_estimate_bitrate = true;
 182     p_sys->i_bitrate_avg = 0;
 183     p_sys->b_big_endian = false;
 184     p_sys->f_fps = var_InheritFloat( p_demux, "es-fps" );
 185     p_sys->p_packetized_data = NULL;
 186
 187     if( stream_Seek( p_demux->s, p_sys->i_stream_offset ) )
 188     {
 189         free( p_sys );
 190         return VLC_EGENERIC;
 191     }
 192
 193     if( p_sys->codec.pf_init( p_demux ) )
 194     {
 195         free( p_sys );
 196         return VLC_EGENERIC;
 197     }
 198
 199     msg_Dbg( p_demux, "detected format %4.4s", (const char*)&p_sys->codec.i_codec );
 200
 201     /* Load the audio packetizer */
 202     es_format_Init( &fmt, i_cat, p_sys->codec.i_codec );
 203     p_sys->p_packetizer = demux_PacketizerNew( p_demux, &fmt, p_sys->codec.psz_name );
 204     if( !p_sys->p_packetizer )
 205     {
 206         free( p_sys );
 207         return VLC_EGENERIC;
 208     }
 209
 210     while( vlc_object_alive( p_demux ) )
 211     {
 212         if( Parse( p_demux, &p_sys->p_packetized_data ) )
 213             break;
 214         if( p_sys->p_packetized_data )
 215             break;
 216     }
 217     return VLC_SUCCESS;
 218 }
 219 static int OpenAudio( vlc_object_t *p_this )
 220 {
 221     demux_t *p_demux = (demux_t*)p_this;
 222     for( int i = 0; p_codecs[i].i_codec != 0; i++ )
 223     {
 224         int64_t i_offset;
 225         if( !p_codecs[i].pf_probe( p_demux, &i_offset ) )
 226             return OpenCommon( p_demux, AUDIO_ES, &p_codecs[i], i_offset );
 227     }
 228     return VLC_EGENERIC;
 229 }
 230 static int OpenVideo( vlc_object_t *p_this )
 231 {
 232     demux_t *p_demux = (demux_t*)p_this;
 233
 234     /* Only m4v is supported for the moment */
 235     bool b_m4v_ext    = demux_IsPathExtension( p_demux, ".m4v" );
 236     bool b_m4v_forced = demux_IsForced( p_demux, "m4v" ) ||
 237                         demux_IsForced( p_demux, "mp4v" );
 238     if( !b_m4v_ext && !b_m4v_forced )
 239         return VLC_EGENERIC;
 240
 241     const uint8_t *p_peek;
 242     if( stream_Peek( p_demux->s, &p_peek, 4 ) < 4 )
 243         return VLC_EGENERIC;
 244     if( p_peek[0] != 0x00 || p_peek[1] != 0x00 || p_peek[2] != 0x01 )
 245     {
 246         if( !b_m4v_forced)
 247             return VLC_EGENERIC;
 248         msg_Warn( p_demux,
 249                   "this doesn't look like an MPEG ES stream, continuing anyway" );
 250     }
 251     return OpenCommon( p_demux, VIDEO_ES, &codec_m4v, 0 );
 252 }
 253 /*****************************************************************************
 254  * Demux: reads and demuxes data packets
 255  *****************************************************************************
 256  * Returns -1 in case of error, 0 in case of EOF, 1 otherwise
 257  *****************************************************************************/
 258 static int Demux( demux_t *p_demux )
 259 {
 260     int ret = 1;
 261     demux_sys_t *p_sys = p_demux->p_sys;
 262
 263     block_t *p_block_out = p_sys->p_packetized_data;
 264     if( p_block_out )
 265         p_sys->p_packetized_data = NULL;
 266     else
 267         ret = Parse( p_demux, &p_block_out ) ? 0 : 1;
 268
 269     while( p_block_out )
 270     {
 271         block_t *p_next = p_block_out->p_next;
 272
 273         /* Correct timestamp */
 274         if( p_sys->p_packetizer->fmt_out.i_cat == VIDEO_ES )
 275         {
 276             if( p_block_out->i_pts <= VLC_TS_INVALID &&
 277                 p_block_out->i_dts <= VLC_TS_INVALID )
 278                 p_block_out->i_dts = VLC_TS_0 + p_sys->i_pts + 1000000 / p_sys->f_fps;
 279             if( p_block_out->i_dts > VLC_TS_INVALID )
 280                 p_sys->i_pts = p_block_out->i_dts - VLC_TS_0;
 281         }
 282         else
 283         {
 284             p_sys->i_pts = p_block_out->i_pts - VLC_TS_0;
 285         }
 286
 287         if( p_block_out->i_pts > VLC_TS_INVALID )
 288         {
 289             p_block_out->i_pts += p_sys->i_time_offset;
 290         }
 291         if( p_block_out->i_dts > VLC_TS_INVALID )
 292         {
 293             p_block_out->i_dts += p_sys->i_time_offset;
 294             es_out_Control( p_demux->out, ES_OUT_SET_PCR, p_block_out->i_dts );
 295         }
 296         /* Re-estimate bitrate */
 297         if( p_sys->b_estimate_bitrate && p_sys->i_pts > INT64_C(500000) )
 298             p_sys->i_bitrate_avg = 8*INT64_C(1000000)*p_sys->i_bytes/(p_sys->i_pts-1);
 299         p_sys->i_bytes += p_block_out->i_buffer;
 300
 301
 302         p_block_out->p_next = NULL;
 303         es_out_Send( p_demux->out, p_sys->p_es, p_block_out );
 304
 305         p_block_out = p_next;
 306     }
 307     return ret;
 308 }
 309
 310 /*****************************************************************************
 311  * Close: frees unused data
 312  *****************************************************************************/
 313 static void Close( vlc_object_t * p_this )
 314 {
 315     demux_t     *p_demux = (demux_t*)p_this;
 316     demux_sys_t *p_sys = p_demux->p_sys;
 317
 318     if( p_sys->p_packetized_data )
 319         block_ChainRelease( p_sys->p_packetized_data );
 320     demux_PacketizerDestroy( p_sys->p_packetizer );
 321     free( p_sys );
 322 }
 323
 324 /*****************************************************************************
 325  * Control:
 326  *****************************************************************************/
 327 static int Control( demux_t *p_demux, int i_query, va_list args )
 328 {
 329     demux_sys_t *p_sys  = p_demux->p_sys;
 330     int64_t *pi64;
 331     bool *pb_bool;
 332     int i_ret;
 333     va_list args_save;
 334
 335     va_copy ( args_save, args );
 336
 337     switch( i_query )
 338     {
 339         case DEMUX_HAS_UNSUPPORTED_META:
 340             pb_bool = (bool*)va_arg( args, bool* );
 341             *pb_bool = true;
 342             return VLC_SUCCESS;
 343
 344         case DEMUX_GET_TIME:
 345             pi64 = (int64_t*)va_arg( args, int64_t * );
 346             *pi64 = p_sys->i_pts + p_sys->i_time_offset;
 347             return VLC_SUCCESS;
 348
 349         case DEMUX_GET_LENGTH:
 350             i_ret = demux_vaControlHelper( p_demux->s, p_sys->i_stream_offset, -1,
 351                                             p_sys->i_bitrate_avg, 1, i_query,
 352                                             args );
 353             /* No bitrate, we can't have it precisely, but we can compute
 354              * a raw approximation with time/position */
 355             if( i_ret && !p_sys->i_bitrate_avg )
 356             {
 357                 float f_pos = (double)(uint64_t)( stream_Tell( p_demux->s ) ) /
 358                               (double)(uint64_t)( stream_Size( p_demux->s ) );
 359                 /* The first few seconds are guaranteed to be very whacky,
 360                  * don't bother trying ... Too bad */
 361                 if( f_pos < 0.01 ||
 362                     (p_sys->i_pts + p_sys->i_time_offset) < 8000000 )
 363                     return VLC_EGENERIC;
 364
 365                 pi64 = (int64_t *)va_arg( args_save, int64_t * );
 366                 *pi64 = (p_sys->i_pts + p_sys->i_time_offset) / f_pos;
 367                 return VLC_SUCCESS;
 368             }
 369             va_end( args_save );
 370             return i_ret;
 371
 372         case DEMUX_SET_TIME:
 373             /* FIXME TODO: implement a high precision seek (with mp3 parsing)
 374              * needed for multi-input */
 375         default:
 376             i_ret = demux_vaControlHelper( p_demux->s, p_sys->i_stream_offset, -1,
 377                                             p_sys->i_bitrate_avg, 1, i_query,
 378                                             args );
 379             if( !i_ret && p_sys->i_bitrate_avg > 0 &&
 380                 (i_query == DEMUX_SET_POSITION || i_query == DEMUX_SET_TIME) )
 381             {
 382                 int64_t i_time = INT64_C(8000000) * ( stream_Tell(p_demux->s) - p_sys->i_stream_offset ) /
 383                     p_sys->i_bitrate_avg;
 384
 385                 /* Fix time_offset */
 386                 if( i_time >= 0 )
 387                     p_sys->i_time_offset = i_time - p_sys->i_pts;
 388                 /* And reset buffered data */
 389                 if( p_sys->p_packetized_data )
 390                     block_ChainRelease( p_sys->p_packetized_data );
 391                 p_sys->p_packetized_data = NULL;
 392             }
 393             return i_ret;
 394     }
 395 }
 396
 397 /*****************************************************************************
 398  * Makes a link list of buffer of parsed data
 399  * Returns true if EOF
 400  *****************************************************************************/
 401 static bool Parse( demux_t *p_demux, block_t **pp_output )
 402 {
 403     demux_sys_t *p_sys = p_demux->p_sys;
 404     block_t *p_block_in, *p_block_out;
 405
 406     *pp_output = NULL;
 407
 408     if( p_sys->codec.b_use_word )
 409     {
 410         /* Make sure we are word aligned */
 411         int64_t i_pos = stream_Tell( p_demux->s );
 412         if( i_pos % 2 )
 413             stream_Read( p_demux->s, NULL, 1 );
 414     }
 415
 416     p_block_in = stream_Block( p_demux->s, p_sys->i_packet_size );
 417     bool b_eof = p_block_in == NULL;
 418
 419     if( p_block_in )
 420     {
 421         if( p_sys->codec.b_use_word && !p_sys->b_big_endian && p_block_in->i_buffer > 0 )
 422         {
 423             /* Convert to big endian */
 424             swab( p_block_in->p_buffer, p_block_in->p_buffer, p_block_in->i_buffer );
 425         }
 426
 427         p_block_in->i_pts = p_block_in->i_dts = p_sys->b_start || p_sys->b_initial_sync_failed ? VLC_TS_0 : VLC_TS_INVALID;
 428     }
 429     p_sys->b_initial_sync_failed = p_sys->b_start; /* Only try to resync once */
 430
 431     while( ( p_block_out = p_sys->p_packetizer->pf_packetize( p_sys->p_packetizer, p_block_in ? &p_block_in : NULL ) ) )
 432     {
 433         p_sys->b_initial_sync_failed = false;
 434         while( p_block_out )
 435         {
 436             if( !p_sys->p_es )
 437             {
 438                 p_sys->p_packetizer->fmt_out.b_packetized = true;
 439                 p_sys->p_es = es_out_Add( p_demux->out,
 440                                           &p_sys->p_packetizer->fmt_out);
 441
 442
 443                 /* Try the xing header */
 444                 if( p_sys->xing.i_bytes && p_sys->xing.i_frames &&
 445                     p_sys->xing.i_frame_samples )
 446                 {
 447                     p_sys->i_bitrate_avg = p_sys->xing.i_bytes * INT64_C(8) *
 448                         p_sys->p_packetizer->fmt_out.audio.i_rate /
 449                         p_sys->xing.i_frames / p_sys->xing.i_frame_samples;
 450
 451                     if( p_sys->i_bitrate_avg > 0 )
 452                         p_sys->b_estimate_bitrate = false;
 453                 }
 454                 /* Use the bitrate as initual value */
 455                 if( p_sys->b_estimate_bitrate )
 456                     p_sys->i_bitrate_avg = p_sys->p_packetizer->fmt_out.i_bitrate;
 457             }
 458
 459             block_t *p_next = p_block_out->p_next;
 460             p_block_out->p_next = NULL;
 461
 462             block_ChainLastAppend( &pp_output, p_block_out );
 463
 464             p_block_out = p_next;
 465         }
 466     }
 467
 468     if( p_sys->b_initial_sync_failed )
 469         msg_Dbg( p_demux, "did not sync on first block" );
 470     p_sys->b_start = false;
 471
 472     return b_eof;
 473 }
 474
 475 /*****************************************************************************
 476  * Wav header skipper
 477  *****************************************************************************/
 478 #define WAV_PROBE_SIZE (512*1024)
 479 static int WavSkipHeader( demux_t *p_demux, int *pi_skip, const int pi_format[] )
 480 {
 481     const uint8_t *p_peek;
 482     int         i_peek = 0;
 483
 484     /* */
 485     *pi_skip = 0;
 486
 487     /* Check if we are dealing with a WAV file */
 488     if( stream_Peek( p_demux->s, &p_peek, 12+8 ) != 12 + 8 )
 489         return VLC_SUCCESS;
 490
 491     if( memcmp( p_peek, "RIFF", 4 ) || memcmp( &p_peek[8], "WAVE", 4 ) )
 492         return VLC_SUCCESS;
 493
 494     /* Find the wave format header */
 495     i_peek = 12 + 8;
 496     while( memcmp( p_peek + i_peek - 8, "fmt ", 4 ) )
 497     {
 498         uint32_t i_len = GetDWLE( p_peek + i_peek - 4 );
 499         if( i_len > WAV_PROBE_SIZE || i_peek + i_len > WAV_PROBE_SIZE )
 500             return VLC_EGENERIC;
 501
 502         i_peek += i_len + 8;
 503         if( stream_Peek( p_demux->s, &p_peek, i_peek ) != i_peek )
 504             return VLC_EGENERIC;
 505     }
 506
 507     /* Sanity check the wave format header */
 508     uint32_t i_len = GetDWLE( p_peek + i_peek - 4 );
 509     if( i_len > WAV_PROBE_SIZE )
 510         return VLC_EGENERIC;
 511
 512     i_peek += i_len + 8;
 513     if( stream_Peek( p_demux->s, &p_peek, i_peek ) != i_peek )
 514         return VLC_EGENERIC;
 515     const int i_format = GetWLE( p_peek + i_peek - i_len - 8 /* wFormatTag */ );
 516     int i_format_idx;
 517     for( i_format_idx = 0; pi_format[i_format_idx] != WAVE_FORMAT_UNKNOWN; i_format_idx++ )
 518     {
 519         if( i_format == pi_format[i_format_idx] )
 520             break;
 521     }
 522     if( pi_format[i_format_idx] == WAVE_FORMAT_UNKNOWN )
 523         return VLC_EGENERIC;
 524
 525     if( i_format == WAVE_FORMAT_PCM )
 526     {
 527         if( GetWLE( p_peek + i_peek - i_len - 6 /* nChannels */ ) != 2 )
 528             return VLC_EGENERIC;
 529         if( GetDWLE( p_peek + i_peek - i_len - 4 /* nSamplesPerSec */ ) !=
 530             44100 )
 531             return VLC_EGENERIC;
 532     }
 533
 534     /* Skip the wave header */
 535     while( memcmp( p_peek + i_peek - 8, "data", 4 ) )
 536     {
 537         uint32_t i_len = GetDWLE( p_peek + i_peek - 4 );
 538         if( i_len > WAV_PROBE_SIZE || i_peek + i_len > WAV_PROBE_SIZE )
 539             return VLC_EGENERIC;
 540
 541         i_peek += i_len + 8;
 542         if( stream_Peek( p_demux->s, &p_peek, i_peek ) != i_peek )
 543             return VLC_EGENERIC;
 544     }
 545     *pi_skip = i_peek;
 546     return VLC_SUCCESS;
 547 }
 548
 549 static int GenericProbe( demux_t *p_demux, int64_t *pi_offset,
 550                          const char * ppsz_name[],
 551                          int (*pf_check)( const uint8_t *, int * ), int i_check_size,
 552                          const int pi_wav_format[] )
 553 {
 554     bool   b_forced_demux;
 555
 556     int64_t i_offset;
 557     const uint8_t *p_peek;
 558     int i_skip;
 559
 560     b_forced_demux = false;
 561     for( int i = 0; ppsz_name[i] != NULL; i++ )
 562     {
 563         b_forced_demux |= demux_IsForced( p_demux, ppsz_name[i] );
 564     }
 565
 566     i_offset = stream_Tell( p_demux->s );
 567
 568     if( WavSkipHeader( p_demux, &i_skip, pi_wav_format ) )
 569     {
 570         if( !b_forced_demux )
 571             return VLC_EGENERIC;
 572     }
 573     const bool b_wav = i_skip > 0;
 574
 575     /* peek the begining
 576      * It is common that wav files have some sort of garbage at the begining
 577      * We will accept probing 0.5s of data in this case.
 578      */
 579     const int i_probe = i_skip + i_check_size + 8000 + ( b_wav ? (44000/2*2*2) : 0);
 580     const int i_peek = stream_Peek( p_demux->s, &p_peek, i_probe );
 581     if( i_peek < i_skip + i_check_size )
 582     {
 583         msg_Err( p_demux, "cannot peek" );
 584         return VLC_EGENERIC;
 585     }
 586     for( ;; )
 587     {
 588         if( i_skip + i_check_size > i_peek )
 589         {
 590             if( !b_forced_demux )
 591                 return VLC_EGENERIC;
 592             break;
 593         }
 594         int i_samples = 0;
 595         int i_size = pf_check( &p_peek[i_skip], &i_samples );
 596         if( i_size >= 0 )
 597         {
 598             if( i_size == 0 )
 599                 break;
 600
 601             /* If we have the frame size, check the next frame for
 602              * extra robustness
 603              * The second test is because some .wav have paddings
 604              */
 605             bool b_ok = false;
 606             for( int t = 0; t < 1 + !!b_wav; t++ )
 607             {
 608                 if( t == 1 )
 609                     i_size = i_samples * 2 * 2;
 610                 if( i_skip + i_check_size + i_size <= i_peek )
 611                 {
 612                     b_ok = pf_check( &p_peek[i_skip+i_size], NULL ) >= 0;
 613                     if( b_ok )
 614                         break;
 615                 }
 616             }
 617             if( b_ok )
 618                 break;
 619         }
 620         i_skip++;
 621         if( !b_wav && !b_forced_demux )
 622             return VLC_EGENERIC;
 623     }
 624
 625     *pi_offset = i_offset + i_skip;
 626     return VLC_SUCCESS;
 627 }
 628
 629 /*****************************************************************************
 630  * Mpeg I/II Audio
 631  *****************************************************************************/
 632 static int MpgaCheckSync( const uint8_t *p_peek )
 633 {
 634     uint32_t h = GetDWBE( p_peek );
 635
 636     if( ((( h >> 21 )&0x07FF) != 0x07FF )   /* header sync */
 637         || (((h >> 19)&0x03) == 1 )         /* valid version ID ? */
 638         || (((h >> 17)&0x03) == 0 )         /* valid layer ?*/
 639         || (((h >> 12)&0x0F) == 0x0F )      /* valid bitrate ?*/
 640         || (((h >> 10) & 0x03) == 0x03 )    /* valide sampling freq ? */
 641         || ((h & 0x03) == 0x02 ))           /* valid emphasis ? */
 642     {
 643         return false;
 644     }
 645     return true;
 646 }
 647
 648 #define MPGA_VERSION( h )   ( 1 - (((h)>>19)&0x01) )
 649 #define MPGA_MODE(h)        (((h)>> 6)&0x03)
 650
 651 static int MpgaGetFrameSamples( uint32_t h )
 652 {
 653     const int i_layer = 3 - (((h)>>17)&0x03);
 654     switch( i_layer )
 655     {
 656     case 0:
 657         return 384;
 658     case 1:
 659         return 1152;
 660     case 2:
 661         return MPGA_VERSION(h) ? 576 : 1152;
 662     default:
 663         return 0;
 664     }
 665 }
 666
 667 static int MpgaProbe( demux_t *p_demux, int64_t *pi_offset )
 668 {
 669     const int pi_wav[] = { WAVE_FORMAT_MPEG, WAVE_FORMAT_MPEGLAYER3, WAVE_FORMAT_UNKNOWN };
 670     bool   b_forced;
 671     bool   b_forced_demux;
 672     int64_t i_offset;
 673
 674     const uint8_t *p_peek;
 675     int i_skip;
 676
 677     b_forced = demux_IsPathExtension( p_demux, ".mp3" );
 678     b_forced_demux = demux_IsForced( p_demux, "mp3" ) ||
 679                      demux_IsForced( p_demux, "mpga" );
 680
 681     i_offset = stream_Tell( p_demux->s );
 682
 683     if( WavSkipHeader( p_demux, &i_skip, pi_wav ) )
 684     {
 685         if( !b_forced_demux )
 686             return VLC_EGENERIC;
 687
 688         return VLC_EGENERIC;
 689     }
 690
 691     if( stream_Peek( p_demux->s, &p_peek, i_skip + 4 ) < i_skip + 4 )
 692         return VLC_EGENERIC;
 693
 694     if( !MpgaCheckSync( &p_peek[i_skip] ) )
 695     {
 696         bool b_ok = false;
 697         int i_peek;
 698
 699         if( !b_forced_demux && !b_forced )
 700             return VLC_EGENERIC;
 701
 702         i_peek = stream_Peek( p_demux->s, &p_peek, i_skip + 8096 );
 703         while( i_skip + 4 < i_peek )
 704         {
 705             if( MpgaCheckSync( &p_peek[i_skip] ) )
 706             {
 707                 b_ok = true;
 708                 break;
 709             }
 710             i_skip++;
 711         }
 712         if( !b_ok && !b_forced_demux )
 713             return VLC_EGENERIC;
 714     }
 715     *pi_offset = i_offset + i_skip;
 716     return VLC_SUCCESS;
 717 }
 718
 719 static void MpgaXingSkip( const uint8_t **pp_xing, int *pi_xing, int i_count )
 720 {
 721     if(i_count > *pi_xing )
 722         i_count = *pi_xing;
 723
 724     (*pp_xing) += i_count;
 725     (*pi_xing) -= i_count;
 726 }
 727
 728 static uint32_t MpgaXingGetDWBE( const uint8_t **pp_xing, int *pi_xing, uint32_t i_default )
 729 {
 730     if( *pi_xing < 4 )
 731         return i_default;
 732
 733     uint32_t v = GetDWBE( *pp_xing );
 734
 735     MpgaXingSkip( pp_xing, pi_xing, 4 );
 736
 737     return v;
 738 }
 739
 740 static int MpgaInit( demux_t *p_demux )
 741 {
 742     demux_sys_t *p_sys = p_demux->p_sys;
 743
 744     const uint8_t *p_peek;
 745     int i_peek;
 746
 747     /* */
 748     p_sys->i_packet_size = 1024;
 749
 750     /* Load a potential xing header */
 751     i_peek = stream_Peek( p_demux->s, &p_peek, 4 + 1024 );
 752     if( i_peek < 4 + 21 )
 753         return VLC_SUCCESS;
 754
 755     const uint32_t header = GetDWBE( p_peek );
 756     if( !MpgaCheckSync( p_peek ) )
 757         return VLC_SUCCESS;
 758
 759     /* Xing header */
 760     const uint8_t *p_xing = p_peek;
 761     int i_xing = i_peek;
 762     int i_skip;
 763
 764     if( MPGA_VERSION( header ) == 0 )
 765         i_skip = MPGA_MODE( header ) != 3 ? 36 : 21;
 766     else
 767         i_skip = MPGA_MODE( header ) != 3 ? 21 : 13;
 768
 769     if( i_skip + 8 >= i_xing || memcmp( &p_xing[i_skip], "Xing", 4 ) )
 770         return VLC_SUCCESS;
 771
 772     const uint32_t i_flags = GetDWBE( &p_xing[i_skip+4] );
 773
 774     MpgaXingSkip( &p_xing, &i_xing, i_skip + 8 );
 775
 776     if( i_flags&0x01 )
 777         p_sys->xing.i_frames = MpgaXingGetDWBE( &p_xing, &i_xing, 0 );
 778     if( i_flags&0x02 )
 779         p_sys->xing.i_bytes = MpgaXingGetDWBE( &p_xing, &i_xing, 0 );
 780     if( i_flags&0x04 ) /* TODO Support XING TOC to improve seeking accuracy */
 781         MpgaXingSkip( &p_xing, &i_xing, 100 );
 782     if( i_flags&0x08 )
 783     {
 784         /* FIXME: doesn't return the right bitrage average, at least
 785            with some MP3's */
 786         p_sys->xing.i_bitrate_avg = MpgaXingGetDWBE( &p_xing, &i_xing, 0 );
 787         msg_Dbg( p_demux, "xing vbr value present (%d)",
 788                  p_sys->xing.i_bitrate_avg );
 789     }
 790
 791     if( p_sys->xing.i_frames > 0 && p_sys->xing.i_bytes > 0 )
 792     {
 793         p_sys->xing.i_frame_samples = MpgaGetFrameSamples( header );
 794         msg_Dbg( p_demux, "xing frames&bytes value present "
 795                  "(%d bytes, %d frames, %d samples/frame)",
 796                  p_sys->xing.i_bytes, p_sys->xing.i_frames,
 797                  p_sys->xing.i_frame_samples );
 798     }
 799     return VLC_SUCCESS;
 800 }
 801
 802 /*****************************************************************************
 803  * AAC
 804  *****************************************************************************/
 805 static int AacProbe( demux_t *p_demux, int64_t *pi_offset )
 806 {
 807     bool   b_forced;
 808     bool   b_forced_demux;
 809
 810     int64_t i_offset;
 811     const uint8_t *p_peek;
 812
 813     b_forced = demux_IsPathExtension( p_demux, ".aac" ) ||
 814                demux_IsPathExtension( p_demux, ".aacp" );
 815     b_forced_demux = demux_IsForced( p_demux, "m4a" ) ||
 816                      demux_IsForced( p_demux, "aac" ) ||
 817                      demux_IsForced( p_demux, "mp4a" );
 818
 819     if( !b_forced_demux && !b_forced )
 820         return VLC_EGENERIC;
 821
 822     i_offset = stream_Tell( p_demux->s );
 823
 824     /* peek the begining (10 is for adts header) */
 825     if( stream_Peek( p_demux->s, &p_peek, 10 ) < 10 )
 826     {
 827         msg_Err( p_demux, "cannot peek" );
 828         return VLC_EGENERIC;
 829     }
 830     if( !strncmp( (char *)p_peek, "ADIF", 4 ) )
 831     {
 832         msg_Err( p_demux, "ADIF file. Not yet supported. (Please report)" );
 833         return VLC_EGENERIC;
 834     }
 835
 836     *pi_offset = i_offset;
 837     return VLC_SUCCESS;
 838 }
 839 static int AacInit( demux_t *p_demux )
 840 {
 841     demux_sys_t *p_sys = p_demux->p_sys;
 842
 843     p_sys->i_packet_size = 4096;
 844
 845     return VLC_SUCCESS;
 846 }
 847
 848
 849 /*****************************************************************************
 850  * A52
 851  *****************************************************************************/
 852 static int A52CheckSync( const uint8_t *p_peek, bool *p_big_endian, int *pi_samples, bool b_eac3 )
 853 {
 854     vlc_a52_header_t header;
 855     uint8_t p_tmp[VLC_A52_HEADER_SIZE];
 856
 857     *p_big_endian =  p_peek[0] == 0x0b && p_peek[1] == 0x77;
 858     if( !*p_big_endian )
 859     {
 860         swab( p_peek, p_tmp, VLC_A52_HEADER_SIZE );
 861         p_peek = p_tmp;
 862     }
 863
 864     if( vlc_a52_header_Parse( &header, p_peek, VLC_A52_HEADER_SIZE ) )
 865         return VLC_EGENERIC;
 866
 867     if( !header.b_eac3 != !b_eac3 )
 868         return VLC_EGENERIC;
 869     if( pi_samples )
 870         *pi_samples = header.i_samples;
 871     return header.i_size;
 872 }
 873 static int EA52CheckSyncProbe( const uint8_t *p_peek, int *pi_samples )
 874 {
 875     bool b_dummy;
 876     return A52CheckSync( p_peek, &b_dummy, pi_samples, true );
 877 }
 878
 879 static int EA52Probe( demux_t *p_demux, int64_t *pi_offset )
 880 {
 881     const char *ppsz_name[] = { "eac3", NULL };
 882     const int pi_wav[] = { WAVE_FORMAT_PCM, WAVE_FORMAT_A52, WAVE_FORMAT_UNKNOWN };
 883
 884     return GenericProbe( p_demux, pi_offset, ppsz_name, EA52CheckSyncProbe, VLC_A52_HEADER_SIZE, pi_wav );
 885 }
 886
 887 static int A52CheckSyncProbe( const uint8_t *p_peek, int *pi_samples )
 888 {
 889     bool b_dummy;
 890     return A52CheckSync( p_peek, &b_dummy, pi_samples, false );
 891 }
 892
 893 static int A52Probe( demux_t *p_demux, int64_t *pi_offset )
 894 {
 895     const char *ppsz_name[] = { "a52", "ac3", NULL };
 896     const int pi_wav[] = { WAVE_FORMAT_PCM, WAVE_FORMAT_A52, WAVE_FORMAT_UNKNOWN };
 897
 898     return GenericProbe( p_demux, pi_offset, ppsz_name, A52CheckSyncProbe, VLC_A52_HEADER_SIZE, pi_wav );
 899 }
 900
 901 static int A52Init( demux_t *p_demux )
 902 {
 903     demux_sys_t *p_sys = p_demux->p_sys;
 904
 905     p_sys->b_big_endian = false;
 906     p_sys->i_packet_size = 1024;
 907
 908     const uint8_t *p_peek;
 909
 910     /* peek the begining */
 911     if( stream_Peek( p_demux->s, &p_peek, VLC_A52_HEADER_SIZE ) >= VLC_A52_HEADER_SIZE )
 912     {
 913         A52CheckSync( p_peek, &p_sys->b_big_endian, NULL, true );
 914     }
 915     return VLC_SUCCESS;
 916 }
 917
 918 /*****************************************************************************
 919  * DTS
 920  *****************************************************************************/
 921 static int DtsCheckSync( const uint8_t *p_peek, int *pi_samples )
 922 {
 923     unsigned int i_sample_rate, i_bit_rate, i_frame_length, i_audio_mode;
 924     bool b_dts_hd;
 925
 926     VLC_UNUSED(pi_samples);
 927
 928     int i_frame_size = GetSyncInfo( p_peek,
 929                                     &b_dts_hd,
 930                                     &i_sample_rate,
 931                                     &i_bit_rate,
 932                                     &i_frame_length,
 933                                     &i_audio_mode );
 934
 935     if( i_frame_size != VLC_EGENERIC && i_frame_size <= 8192 )
 936         return VLC_SUCCESS;
 937     else
 938         return VLC_EGENERIC;
 939 }
 940
 941 static int DtsProbe( demux_t *p_demux, int64_t *pi_offset )
 942 {
 943     const char *ppsz_name[] = { "dts", NULL };
 944     const int pi_wav[] = { WAVE_FORMAT_PCM, WAVE_FORMAT_DTS, WAVE_FORMAT_UNKNOWN };
 945
 946     return GenericProbe( p_demux, pi_offset, ppsz_name, DtsCheckSync, 11, pi_wav );
 947 }
 948 static int DtsInit( demux_t *p_demux )
 949 {
 950     demux_sys_t *p_sys = p_demux->p_sys;
 951
 952     p_sys->i_packet_size = 16384;
 953
 954     return VLC_SUCCESS;
 955 }
 956
 957 /*****************************************************************************
 958  * MLP
 959  *****************************************************************************/
 960 static int MlpCheckSync( const uint8_t *p_peek, int *pi_samples )
 961 {
 962     if( p_peek[4+0] != 0xf8 || p_peek[4+1] != 0x72 || p_peek[4+2] != 0x6f )
 963         return -1;
 964
 965     if( p_peek[4+3] != 0xba && p_peek[4+3] != 0xbb )
 966         return -1;
 967
 968     /* TODO checksum and real size for robustness */
 969     VLC_UNUSED(pi_samples);
 970     return 0;
 971 }
 972 static int MlpProbe( demux_t *p_demux, int64_t *pi_offset )
 973 {
 974     const char *ppsz_name[] = { "mlp", "thd", NULL };
 975     const int pi_wav[] = { WAVE_FORMAT_PCM, WAVE_FORMAT_UNKNOWN };
 976
 977     return GenericProbe( p_demux, pi_offset, ppsz_name, MlpCheckSync, 4+28+16*4, pi_wav );
 978 }
 979 static int MlpInit( demux_t *p_demux )
 980
 981 {
 982     demux_sys_t *p_sys = p_demux->p_sys;
 983
 984     p_sys->i_packet_size = 4096;
 985
 986     return VLC_SUCCESS;
 987 }
 988
 989 /*****************************************************************************
 990  * Video
 991  *****************************************************************************/
 992 static int VideoInit( demux_t *p_demux )
 993 {
 994     demux_sys_t *p_sys = p_demux->p_sys;
 995
 996     p_sys->i_packet_size = 4096;
 997
 998     return VLC_SUCCESS;
 999 }