modules/demux/dts.c

   1 /*****************************************************************************
   2  * dts.c : raw DTS stream input module for vlc
   3  *****************************************************************************
   4  * Copyright (C) 2001-2007 the VideoLAN team
   5  * $Id$
   6  *
   7  * Authors: Gildas Bazin <gbazin@netcourrier.com>
   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_demux.h>
  34 #include <vlc_codec.h>
  35
  36 /*****************************************************************************
  37  * Module descriptor
  38  *****************************************************************************/
  39 static int  Open  ( vlc_object_t * );
  40 static void Close ( vlc_object_t * );
  41
  42 vlc_module_begin();
  43     set_category( CAT_INPUT );
  44     set_subcategory( SUBCAT_INPUT_DEMUX );
  45     set_description( N_("Raw DTS demuxer") );
  46     set_capability( "demux", 155 );
  47     set_callbacks( Open, Close );
  48     add_shortcut( "dts" );
  49 vlc_module_end();
  50
  51 /*****************************************************************************
  52  * Local prototypes
  53  *****************************************************************************/
  54 static int Demux  ( demux_t * );
  55 static int Control( demux_t *, int, va_list );
  56
  57 struct demux_sys_t
  58 {
  59     bool  b_start;
  60     es_out_id_t *p_es;
  61
  62     /* Packetizer */
  63     decoder_t *p_packetizer;
  64
  65     mtime_t i_pts;
  66     mtime_t i_time_offset;
  67
  68     int i_mux_rate;
  69 };
  70
  71 static int CheckSync( const uint8_t *p_peek );
  72
  73 #define DTS_PACKET_SIZE 16384
  74 #define DTS_PROBE_SIZE (DTS_PACKET_SIZE * 4)
  75 #define DTS_MAX_HEADER_SIZE 11
  76
  77 /*****************************************************************************
  78  * Open: initializes ES structures
  79  *****************************************************************************/
  80 static int Open( vlc_object_t * p_this )
  81 {
  82     demux_t     *p_demux = (demux_t*)p_this;
  83     demux_sys_t *p_sys;
  84     const uint8_t *p_peek;
  85     int          i_peek = 0;
  86
  87     /* Check if we are dealing with a WAV file */
  88     if( stream_Peek( p_demux->s, &p_peek, 20 ) == 20 &&
  89         !memcmp( p_peek, "RIFF", 4 ) && !memcmp( &p_peek[8], "WAVE", 4 ) )
  90     {
  91         /* Find the wave format header */
  92         i_peek = 12 + 8;
  93         while( memcmp( p_peek + i_peek - 8, "fmt ", 4 ) )
  94         {
  95             uint32_t i_len = GetDWLE( p_peek + i_peek - 4 );
  96             if( i_len > DTS_PROBE_SIZE || i_peek + i_len > DTS_PROBE_SIZE )
  97                 return VLC_EGENERIC;
  98
  99             i_peek += i_len + 8;
 100             if( stream_Peek( p_demux->s, &p_peek, i_peek ) != i_peek )
 101                 return VLC_EGENERIC;
 102         }
 103
 104         /* Sanity check the wave format header */
 105         uint32_t i_len = GetDWLE( p_peek + i_peek - 4 );
 106         if( i_len > DTS_PROBE_SIZE )
 107             return VLC_EGENERIC;
 108
 109         i_peek += i_len + 8;
 110         if( stream_Peek( p_demux->s, &p_peek, i_peek ) != i_peek )
 111             return VLC_EGENERIC;
 112         if( GetWLE( p_peek + i_peek - i_len - 8 /* wFormatTag */ ) !=
 113             1 /* WAVE_FORMAT_PCM */ )
 114             return VLC_EGENERIC;
 115         if( GetWLE( p_peek + i_peek - i_len - 6 /* nChannels */ ) != 2 )
 116             return VLC_EGENERIC;
 117         if( GetDWLE( p_peek + i_peek - i_len - 4 /* nSamplesPerSec */ ) !=
 118             44100 )
 119             return VLC_EGENERIC;
 120
 121         /* Skip the wave header */
 122         while( memcmp( p_peek + i_peek - 8, "data", 4 ) )
 123         {
 124             uint32_t i_len = GetDWLE( p_peek + i_peek - 4 );
 125             if( i_len > DTS_PROBE_SIZE || i_peek + i_len > DTS_PROBE_SIZE )
 126                 return VLC_EGENERIC;
 127
 128             i_peek += i_len + 8;
 129             if( stream_Peek( p_demux->s, &p_peek, i_peek ) != i_peek )
 130                 return VLC_EGENERIC;
 131         }
 132
 133         /* Some DTS wav files don't begin with a sync code so we do a more
 134          * extensive search */
 135         int i_size = stream_Peek( p_demux->s, &p_peek, DTS_PROBE_SIZE );
 136         i_size -= DTS_MAX_HEADER_SIZE;
 137
 138         while( i_peek < i_size )
 139         {
 140             if( CheckSync( p_peek + i_peek ) != VLC_SUCCESS )
 141                 /* The data is stored in 16 bits words */
 142                 i_peek += 2;
 143             else
 144                 break;
 145         }
 146     }
 147
 148     /* Have a peep at the show. */
 149     CHECK_PEEK( p_peek, i_peek + DTS_MAX_HEADER_SIZE * 2  );
 150
 151     if( CheckSync( p_peek + i_peek ) != VLC_SUCCESS )
 152     {
 153         if( !p_demux->b_force )
 154             return VLC_EGENERIC;
 155
 156         /* User forced */
 157         msg_Err( p_demux, "this doesn't look like a DTS audio stream, "
 158                  "continuing anyway" );
 159     }
 160
 161     DEMUX_INIT_COMMON(); p_sys = p_demux->p_sys;
 162     p_sys->b_start = true;
 163     p_sys->i_mux_rate = 0;
 164     p_sys->i_pts = 0;
 165     p_sys->i_time_offset = 0;
 166
 167     INIT_APACKETIZER( p_sys->p_packetizer, 'd','t','s',' ' );
 168     LOAD_PACKETIZER_OR_FAIL( p_sys->p_packetizer, "DTS" );
 169
 170     p_sys->p_es = es_out_Add( p_demux->out, &p_sys->p_packetizer->fmt_in );
 171
 172     return VLC_SUCCESS;
 173 }
 174
 175 /*****************************************************************************
 176  * Close: frees unused data
 177  *****************************************************************************/
 178 static void Close( vlc_object_t *p_this )
 179 {
 180     demux_t     *p_demux = (demux_t*)p_this;
 181     demux_sys_t *p_sys = p_demux->p_sys;
 182
 183     DESTROY_PACKETIZER( p_sys->p_packetizer );
 184
 185     free( p_sys );
 186 }
 187
 188 /*****************************************************************************
 189  * Demux: reads and demuxes data packets
 190  *****************************************************************************
 191  * Returns -1 in case of error, 0 in case of EOF, 1 otherwise
 192  *****************************************************************************/
 193 static int Demux( demux_t *p_demux )
 194 {
 195     demux_sys_t *p_sys = p_demux->p_sys;
 196     block_t *p_block_in, *p_block_out;
 197
 198     if( !( p_block_in = stream_Block( p_demux->s, DTS_PACKET_SIZE ) ) )
 199     {
 200         return 0;
 201     }
 202
 203     if( p_sys->b_start )
 204         p_block_in->i_pts = p_block_in->i_dts = 1;
 205     else
 206         p_block_in->i_pts = p_block_in->i_dts = 0;
 207
 208     while( (p_block_out = p_sys->p_packetizer->pf_packetize(
 209                 p_sys->p_packetizer, &p_block_in )) )
 210     {
 211         p_sys->b_start = false;
 212
 213         while( p_block_out )
 214         {
 215             block_t *p_next = p_block_out->p_next;
 216
 217             /* We assume a constant bitrate */
 218             if( p_block_out->i_length )
 219             {
 220                 p_sys->i_mux_rate =
 221                     p_block_out->i_buffer * INT64_C(1000000) / p_block_out->i_length;
 222             }
 223
 224             /* Correct timestamp */
 225             p_block_out->i_pts += p_sys->i_time_offset;
 226             p_block_out->i_dts += p_sys->i_time_offset;
 227
 228             /* set PCR */
 229             es_out_Control( p_demux->out, ES_OUT_SET_PCR, p_block_out->i_dts );
 230
 231             es_out_Send( p_demux->out, p_sys->p_es, p_block_out );
 232
 233             p_block_out = p_next;
 234         }
 235     }
 236
 237     return 1;
 238 }
 239
 240 /*****************************************************************************
 241  * Control:
 242  *****************************************************************************/
 243 static int Control( demux_t *p_demux, int i_query, va_list args )
 244 {
 245     demux_sys_t *p_sys  = p_demux->p_sys;
 246     bool *pb_bool;
 247     int64_t *pi64;
 248     int i_ret;
 249
 250     switch( i_query )
 251     {
 252     case DEMUX_HAS_UNSUPPORTED_META:
 253         pb_bool = (bool*)va_arg( args, bool* );
 254         *pb_bool = true;
 255         return VLC_SUCCESS;
 256
 257     case DEMUX_GET_TIME:
 258         pi64 = (int64_t*)va_arg( args, int64_t * );
 259         *pi64 = p_sys->i_pts + p_sys->i_time_offset;
 260         return VLC_SUCCESS;
 261
 262     case DEMUX_SET_TIME: /* TODO implement a high precicsion seek */
 263     default:
 264         i_ret = demux_vaControlHelper( p_demux->s,
 265                                        0, -1,
 266                                        8*p_sys->i_mux_rate, 1, i_query, args );
 267         if( !i_ret && p_sys->i_mux_rate > 0 &&
 268             ( i_query == DEMUX_SET_POSITION || i_query == DEMUX_SET_TIME ) )
 269         {
 270
 271             const int64_t i_time = INT64_C(1000000) * stream_Tell(p_demux->s) /
 272                                         p_sys->i_mux_rate;
 273
 274             /* Fix time_offset */
 275             if( i_time >= 0 )
 276                 p_sys->i_time_offset = i_time - p_sys->i_pts;
 277         }
 278         return i_ret;
 279     }
 280 }
 281
 282 /*****************************************************************************
 283  * CheckSync: Check if buffer starts with a DTS sync code
 284  *****************************************************************************/
 285 static int CheckSync( const uint8_t *p_peek )
 286 {
 287     /* 14 bits, little endian version of the bitstream */
 288     if( p_peek[0] == 0xff && p_peek[1] == 0x1f &&
 289         p_peek[2] == 0x00 && p_peek[3] == 0xe8 &&
 290         (p_peek[4] & 0xf0) == 0xf0 && p_peek[5] == 0x07 )
 291     {
 292         return VLC_SUCCESS;
 293     }
 294     /* 14 bits, big endian version of the bitstream */
 295     else if( p_peek[0] == 0x1f && p_peek[1] == 0xff &&
 296              p_peek[2] == 0xe8 && p_peek[3] == 0x00 &&
 297              p_peek[4] == 0x07 && (p_peek[5] & 0xf0) == 0xf0)
 298     {
 299         return VLC_SUCCESS;
 300     }
 301     /* 16 bits, big endian version of the bitstream */
 302     else if( p_peek[0] == 0x7f && p_peek[1] == 0xfe &&
 303              p_peek[2] == 0x80 && p_peek[3] == 0x01 )
 304     {
 305         return VLC_SUCCESS;
 306     }
 307     /* 16 bits, little endian version of the bitstream */
 308     else if( p_peek[0] == 0xfe && p_peek[1] == 0x7f &&
 309              p_peek[2] == 0x01 && p_peek[3] == 0x80 )
 310     {
 311         return VLC_SUCCESS;
 312     }
 313
 314     return VLC_EGENERIC;
 315 }
 316