text: /*****************************************************************************
   * ogg.c : ogg stream demux module for vlc
   *****************************************************************************
   * Copyright (C) 2001-2007 the VideoLAN team
   * $Id: e659b9cb00841d35a42f10dadc910fc9ad626273 $
   *
   * Authors: Gildas Bazin <gbazin@netcourrier.com>
   *          Andre Pang <Andre.Pang@csiro.au> (Annodex support)
   *
   * This program is free software; you can redistribute it and/or modify
   * it under the terms of the GNU General Public License as published by
   * the Free Software Foundation; either version 2 of the License, or
   * (at your option) any later version.
   *
   * This program is distributed in the hope that it will be useful,
   * but WITHOUT ANY WARRANTY; without even the implied warranty of
   * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   * GNU General Public License for more details.
   *
   * You should have received a copy of the GNU General Public License
   * along with this program; if not, write to the Free Software
   * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301, USA.
   *****************************************************************************/
  
  /*****************************************************************************
   * Preamble
   *****************************************************************************/
  #ifdef HAVE_CONFIG_H
  # include "config.h"
  #endif
  
  #include <vlc_common.h>
  #include <vlc_plugin.h>
  #include <vlc_demux.h>
  #include <vlc_meta.h>
  #include <vlc_input.h>
  
  #include <ogg/ogg.h>
  
  #include <vlc_codecs.h>
  #include <vlc_bits.h>
  #include "xiph.h"
  #include "vorbis.h"
  #include "kate_categories.h"
  #include "ogg.h"
  #include "oggseek.h"
  
  /*****************************************************************************
   * Module descriptor
   *****************************************************************************/
  static int  Open ( vlc_object_t * );
  static void Close( vlc_object_t * );
  
  vlc_module_begin ()
      set_shortname ( "OGG" )
      set_description( N_("OGG demuxer" ) )
      set_category( CAT_INPUT )
      set_subcategory( SUBCAT_INPUT_DEMUX )
      set_capability( "demux", 50 )
      set_callbacks( Open, Close )
      add_shortcut( "ogg" )
  vlc_module_end ()
  
  
  /*****************************************************************************
   * Definitions of structures and functions used by this plugins
   *****************************************************************************/
  
  /* OggDS headers for the new header format (used in ogm files) */
  typedef struct
  {
      ogg_int32_t width;
      ogg_int32_t height;
  } stream_header_video_t;
  
  typedef struct
  {
      ogg_int16_t channels;
      ogg_int16_t padding;
      ogg_int16_t blockalign;
      ogg_int32_t avgbytespersec;
  } stream_header_audio_t;
  
  typedef struct
  {
      char        streamtype[8];
      char        subtype[4];
  
      ogg_int32_t size;                               /* size of the structure */
  
      ogg_int64_t time_unit;                              /* in reference time */
      ogg_int64_t samples_per_unit;
      ogg_int32_t default_len;                                /* in media time */
  
      ogg_int32_t buffersize;
      ogg_int16_t bits_per_sample;
      ogg_int16_t padding;
  
      union
      {
          /* Video specific */
          stream_header_video_t video;
          /* Audio specific */
          stream_header_audio_t audio;
      } sh;
  } stream_header_t;
  
  
  /* Some defines from OggDS */
  #define PACKET_TYPE_HEADER   0x01
  #define PACKET_TYPE_BITS     0x07
  #define PACKET_LEN_BITS01    0xc0
  #define PACKET_LEN_BITS2     0x02
  #define PACKET_IS_SYNCPOINT  0x08
  
  /*****************************************************************************
   * Local prototypes
   *****************************************************************************/
  static int  Demux  ( demux_t * );
  static int  Control( demux_t *, int, va_list );
  
  /* Bitstream manipulation */
  static int  Ogg_ReadPage     ( demux_t *, ogg_page * );
  static void Ogg_UpdatePCR    ( logical_stream_t *, ogg_packet * );
  static void Ogg_DecodePacket ( demux_t *, logical_stream_t *, ogg_packet * );
  
  static int Ogg_BeginningOfStream( demux_t *p_demux );
  static int Ogg_FindLogicalStreams( demux_t *p_demux );
  static void Ogg_EndOfStream( demux_t *p_demux );
  
  /* */
  static void Ogg_LogicalStreamDelete( demux_t *p_demux, logical_stream_t *p_stream );
  static bool Ogg_LogicalStreamResetEsFormat( demux_t *p_demux, logical_stream_t *p_stream );
  
  /* */
  static void Ogg_ExtractMeta( demux_t *p_demux, vlc_fourcc_t i_codec, const uint8_t *p_headers, int i_headers );
  
  /* Logical bitstream headers */
  static void Ogg_ReadTheoraHeader( logical_stream_t *, ogg_packet * );
  static void Ogg_ReadVorbisHeader( logical_stream_t *, ogg_packet * );
  static void Ogg_ReadSpeexHeader( logical_stream_t *, ogg_packet * );
  static void Ogg_ReadKateHeader( logical_stream_t *, ogg_packet * );
  static void Ogg_ReadFlacHeader( demux_t *, logical_stream_t *, ogg_packet * );
  static void Ogg_ReadAnnodexHeader( vlc_object_t *, logical_stream_t *, ogg_packet * );
  static bool Ogg_ReadDiracHeader( logical_stream_t *, ogg_packet * );
  
  /*****************************************************************************
   * Open: initializes ogg demux structures
   *****************************************************************************/
  static int Open( vlc_object_t * p_this )
  {
      demux_t *p_demux = (demux_t *)p_this;
      demux_sys_t    *p_sys;
      const uint8_t  *p_peek;
  
  
      /* Check if we are dealing with an ogg stream */
      if( stream_Peek( p_demux->s, &p_peek, 4 ) < 4 ) return VLC_EGENERIC;
      if( !p_demux->b_force && memcmp( p_peek, "OggS", 4 ) )
      {
          return VLC_EGENERIC;
      }
  
      /* Set exported functions */
      p_demux->pf_demux = Demux;
      p_demux->pf_control = Control;
      p_demux->p_sys = p_sys = malloc( sizeof( demux_sys_t ) );
      if( !p_sys )
          return VLC_ENOMEM;
  
      memset( p_sys, 0, sizeof( demux_sys_t ) );
      p_sys->i_bitrate = 0;
      p_sys->pp_stream = NULL;
      p_sys->p_old_stream = NULL;
  
      /* Begnning of stream, tell the demux to look for elementary streams. */
      p_sys->i_bos = 0;
      p_sys->i_eos = 0;
  
      /* Initialize the Ogg physical bitstream parser */
      ogg_sync_init( &p_sys->oy );
      p_sys->b_page_waiting = false;
  
      /* */
      p_sys->p_meta = NULL;
  
      return VLC_SUCCESS;
  }
  
  /*****************************************************************************
   * Close: frees unused data
   *****************************************************************************/
  static void Close( vlc_object_t *p_this )
  {
      demux_t *p_demux = (demux_t *)p_this;
      demux_sys_t *p_sys = p_demux->p_sys  ;
  
      /* Cleanup the bitstream parser */
      ogg_sync_clear( &p_sys->oy );
  
      Ogg_EndOfStream( p_demux );
  
      if( p_sys->p_old_stream )
          Ogg_LogicalStreamDelete( p_demux, p_sys->p_old_stream );
  
      free( p_sys );
  }
  
  /*****************************************************************************
   * Demux: reads and demuxes data packets
   *****************************************************************************
   * Returns -1 in case of error, 0 in case of EOF, 1 otherwise
   *****************************************************************************/
  static int Demux( demux_t * p_demux )
  {
      demux_sys_t *p_sys = p_demux->p_sys;
      ogg_packet  oggpacket;
      int         i_stream;
      bool b_skipping = false;
  
  
      if( p_sys->i_eos == p_sys->i_streams )
      {
          if( p_sys->i_eos )
          {
              msg_Dbg( p_demux, "end of a group of logical streams" );
              /* We keep the ES to try reusing it in Ogg_BeginningOfStream
               * only 1 ES is supported (common case for ogg web radio) */
              if( p_sys->i_streams == 1 )
              {
                  p_sys->p_old_stream = p_sys->pp_stream[0];
                  TAB_CLEAN( p_sys->i_streams, p_sys->pp_stream );
              }
              Ogg_EndOfStream( p_demux );
          }
  
          p_sys->i_eos = 0;
          if( Ogg_BeginningOfStream( p_demux ) != VLC_SUCCESS )
              return 0;
  
          msg_Dbg( p_demux, "beginning of a group of logical streams" );
          es_out_Control( p_demux->out, ES_OUT_RESET_PCR );
      }
  
      /*
       * The first data page of a physical stream is stored in the relevant logical stream
       * in Ogg_FindLogicalStreams. Therefore, we must not read a page and only update the
       * stream it belongs to if we haven't processed this first page yet. If we do, we
       * will only process that first page whenever we find the second page for this stream.
       * While this is fine for Vorbis and Theora, which are continuous codecs, which means
       * the second page will arrive real quick, this is not fine for Kate, whose second
       * data page will typically arrive much later.
       * This means it is now possible to seek right at the start of a stream where the last
       * logical stream is Kate, without having to wait for the second data page to unblock
       * the first one, which is the one that triggers the 'no more headers to backup' code.
       * And, as we all know, seeking without having backed up all headers is bad, since the
       * codec will fail to initialize if it's missing its headers.
       */
      if( !p_sys->b_page_waiting)
      {
          /*
           * Demux an ogg page from the stream
           */
          if( Ogg_ReadPage( p_demux, &p_sys->current_page ) != VLC_SUCCESS )
              return 0; /* EOF */
  
          /* Test for End of Stream */
          if( ogg_page_eos( &p_sys->current_page ) )
              p_sys->i_eos++;
      }
  
  
      for( i_stream = 0; i_stream < p_sys->i_streams; i_stream++ )
      {
          logical_stream_t *p_stream = p_sys->pp_stream[i_stream];
  
          /* if we've just pulled page, look for the right logical stream */
          if( !p_sys->b_page_waiting )
          {
              if( p_sys->i_streams == 1 &&
                  ogg_page_serialno( &p_sys->current_page ) != p_stream->os.serialno )
              {
                  msg_Err( p_demux, "Broken Ogg stream (serialno) mismatch" );
                  ogg_stream_reset_serialno( &p_stream->os, ogg_page_serialno( &p_sys->current_page ) );
  
                  p_stream->b_reinit = true;
                  p_stream->i_pcr = -1;
                  p_stream->i_interpolated_pcr = -1;
                  es_out_Control( p_demux->out, ES_OUT_RESET_PCR );
              }
  
              if( ogg_stream_pagein( &p_stream->os, &p_sys->current_page ) != 0 )
              {
                  continue;
              }
  
          }
  
          while( ogg_stream_packetout( &p_stream->os, &oggpacket ) > 0 )
          {
              /* Read info from any secondary header packets, if there are any */
              if( p_stream->i_secondary_header_packets > 0 )
              {
                  if( p_stream->fmt.i_codec == VLC_CODEC_THEORA &&
                          oggpacket.bytes >= 7 &&
                          ! memcmp( oggpacket.packet, "\x80theora", 7 ) )
                  {
                      Ogg_ReadTheoraHeader( p_stream, &oggpacket );
                      p_stream->i_secondary_header_packets = 0;
                  }
                  else if( p_stream->fmt.i_codec == VLC_CODEC_VORBIS &&
                          oggpacket.bytes >= 7 &&
                          ! memcmp( oggpacket.packet, "\x01vorbis", 7 ) )
                  {
                      Ogg_ReadVorbisHeader( p_stream, &oggpacket );
                      p_stream->i_secondary_header_packets = 0;
                  }
                  else if( p_stream->fmt.i_codec == VLC_CODEC_CMML )
                  {
                      p_stream->i_secondary_header_packets = 0;
                  }
  
                  /* update start of data pointer */
                  p_stream->i_data_start = stream_Tell( p_demux->s );
  
              }
  
              /* If any streams have i_skip_frames, only decode (pre-roll)
               *  for those streams */
              if ( b_skipping && p_stream->i_skip_frames == 0 ) continue;
  
  
              if( p_stream->b_reinit )
              {
                  /* If synchro is re-initialized we need to drop all the packets
                   * until we find a new dated one. */
                  Ogg_UpdatePCR( p_stream, &oggpacket );
  
                  if( p_stream->i_pcr >= 0 )
                  {
                      p_stream->b_reinit = false;
                  }
                  else
                  {
                      p_stream->i_interpolated_pcr = -1;
                      continue;
                  }
  
                  /* An Ogg/vorbis packet contains an end date granulepos */
                  if( p_stream->fmt.i_codec == VLC_CODEC_VORBIS ||
                      p_stream->fmt.i_codec == VLC_CODEC_SPEEX ||
                      p_stream->fmt.i_codec == VLC_CODEC_FLAC )
                  {
                      if( ogg_stream_packetout( &p_stream->os, &oggpacket ) > 0 )
                      {
                          Ogg_DecodePacket( p_demux, p_stream, &oggpacket );
                      }
                      else
                      {
                          es_out_Control( p_demux->out, ES_OUT_SET_PCR,
                                          VLC_TS_0 + p_stream->i_pcr );
                      }
                      continue;
                  }
              }
  
              Ogg_DecodePacket( p_demux, p_stream, &oggpacket );
          }
  
          if( !p_sys->b_page_waiting )
              break;
      }
  
      /* if a page was waiting, it's now processed */
      p_sys->b_page_waiting = false;
  
      p_sys->i_pcr = -1;
      for( i_stream = 0; i_stream < p_sys->i_streams; i_stream++ )
      {
          logical_stream_t *p_stream = p_sys->pp_stream[i_stream];
  
          if( p_stream->fmt.i_cat == SPU_ES )
              continue;
          if( p_stream->i_interpolated_pcr < 0 )
              continue;
  
          if( p_sys->i_pcr < 0 || p_stream->i_interpolated_pcr < p_sys->i_pcr )
              p_sys->i_pcr = p_stream->i_interpolated_pcr;
      }
  
      if( p_sys->i_pcr >= 0 && ! b_skipping )
          es_out_Control( p_demux->out, ES_OUT_SET_PCR, VLC_TS_0 + p_sys->i_pcr );
  
      return 1;
  }
  
  /*****************************************************************************
   * Control:
   *****************************************************************************/
  static int Control( demux_t *p_demux, int i_query, va_list args )
  {
      demux_sys_t *p_sys  = p_demux->p_sys;
      vlc_meta_t *p_meta;
      int64_t *pi64;
      bool *pb_bool;
      int i;
  
      switch( i_query )
      {
          case DEMUX_GET_META:
              p_meta = (vlc_meta_t *)va_arg( args, vlc_meta_t* );
              if( p_sys->p_meta )
                  vlc_meta_Merge( p_meta, p_sys->p_meta );
              return VLC_SUCCESS;
  
          case DEMUX_HAS_UNSUPPORTED_META:
              pb_bool = (bool*)va_arg( args, bool* );
              *pb_bool = true;
              return VLC_SUCCESS;
  
          case DEMUX_GET_TIME:
              pi64 = (int64_t*)va_arg( args, int64_t * );
              *pi64 = p_sys->i_pcr;
              return VLC_SUCCESS;
  
          case DEMUX_SET_TIME:
              return VLC_EGENERIC;
  
          case DEMUX_SET_POSITION:
              /* forbid seeking if we haven't initialized all logical bitstreams yet;
                 if we allowed, some headers would not get backed up and decoder init
                 would fail, making that logical stream unusable */
              if( p_sys->i_bos > 0 )
              {
                  return VLC_EGENERIC;
              }
  
              for( i = 0; i < p_sys->i_streams; i++ )
              {
                  logical_stream_t *p_stream = p_sys->pp_stream[i];
  
                  /* we'll trash all the data until we find the next pcr */
                  p_stream->b_reinit = true;
                  p_stream->i_pcr = -1;
                  p_stream->i_interpolated_pcr = -1;
                  ogg_stream_reset( &p_stream->os );
              }
              ogg_sync_reset( &p_sys->oy );
              /* XXX The break/return is missing on purpose as
               * demux_vaControlHelper will do the last part of the job */
  
          default:
              return demux_vaControlHelper( p_demux->s, 0, -1, p_sys->i_bitrate,
                                             1, i_query, args );
      }
  }
  
  /****************************************************************************
   * Ogg_ReadPage: Read a full Ogg page from the physical bitstream.
   ****************************************************************************
   * Returns VLC_SUCCESS if a page has been read. An error might happen if we
   * are at the end of stream.
   ****************************************************************************/
  static int Ogg_ReadPage( demux_t *p_demux, ogg_page *p_oggpage )
  {
      demux_sys_t *p_ogg = p_demux->p_sys  ;
      int i_read = 0;
      char *p_buffer;
  
      while( ogg_sync_pageout( &p_ogg->oy, p_oggpage ) != 1 )
      {
          p_buffer = ogg_sync_buffer( &p_ogg->oy, OGGSEEK_BYTES_TO_READ );
  
          i_read = stream_Read( p_demux->s, p_buffer, OGGSEEK_BYTES_TO_READ );
          if( i_read <= 0 )
              return VLC_EGENERIC;
  
          ogg_sync_wrote( &p_ogg->oy, i_read );
      }
  
      return VLC_SUCCESS;
  }
  
  /****************************************************************************
   * Ogg_UpdatePCR: update the PCR (90kHz program clock reference) for the
   *                current stream.
   ****************************************************************************/
  static void Ogg_UpdatePCR( logical_stream_t *p_stream,
                             ogg_packet *p_oggpacket )
  {
      /* Convert the granulepos into a pcr */
      if( p_oggpacket->granulepos >= 0 )
      {
          if( p_stream->fmt.i_codec == VLC_CODEC_THEORA ||
              p_stream->fmt.i_codec == VLC_CODEC_KATE )
          {
              ogg_int64_t iframe = p_oggpacket->granulepos >>
                p_stream->i_granule_shift;
              ogg_int64_t pframe = p_oggpacket->granulepos -
                ( iframe << p_stream->i_granule_shift );
  
              p_stream->i_pcr = ( iframe + pframe - p_stream->i_keyframe_offset )
                * INT64_C(1000000) / p_stream->f_rate;
          }
          else if( p_stream->fmt.i_codec == VLC_CODEC_DIRAC )
          {
              ogg_int64_t i_dts = p_oggpacket->granulepos >> 31;
              /* NB, OggDirac granulepos values are in units of 2*picturerate */
              p_stream->i_pcr = (i_dts/2) * INT64_C(1000000) / p_stream->f_rate;
          }
          else
          {
              p_stream->i_pcr = p_oggpacket->granulepos * INT64_C(1000000)
                                / p_stream->f_rate;
          }
  
          p_stream->i_pcr += 1;
          p_stream->i_interpolated_pcr = p_stream->i_pcr;
      }
      else
      {
          p_stream->i_pcr = -1;
  
          /* no granulepos available, try to interpolate the pcr.
           * If we can't then don't touch the old value. */
          if( p_stream->fmt.i_cat == VIDEO_ES )
              /* 1 frame per packet */
              p_stream->i_interpolated_pcr += (INT64_C(1000000) / p_stream->f_rate);
          else if( p_stream->fmt.i_bitrate )
              p_stream->i_interpolated_pcr +=
                  ( p_oggpacket->bytes * INT64_C(1000000) /
                    p_stream->fmt.i_bitrate / 8 );
      }
  }
  
  /****************************************************************************
   * Ogg_DecodePacket: Decode an Ogg packet.
   ****************************************************************************/
  static void Ogg_DecodePacket( demux_t *p_demux,
                                logical_stream_t *p_stream,
                                ogg_packet *p_oggpacket )
  {
      block_t *p_block;
      bool b_selected;
      int i_header_len = 0;
      mtime_t i_pts = -1, i_interpolated_pts;
      demux_sys_t *p_ogg = p_demux->p_sys;
  
      /* Sanity check */
      if( !p_oggpacket->bytes )
      {
          msg_Dbg( p_demux, "discarding 0 sized packet" );
          return;
      }
  
      if( p_oggpacket->bytes >= 7 &&
          ! memcmp ( p_oggpacket->packet, "Annodex", 7 ) )
      {
          /* it's an Annodex packet -- skip it (do nothing) */
          return;
      }
      else if( p_oggpacket->bytes >= 7 &&
          ! memcmp ( p_oggpacket->packet, "AnxData", 7 ) )
      {
          /* it's an AnxData packet -- skip it (do nothing) */
          return;
      }
  
      if( p_stream->fmt.i_codec == VLC_CODEC_SUBT &&
          p_oggpacket->packet[0] & PACKET_TYPE_BITS ) return;
  
      /* Check the ES is selected */
      es_out_Control( p_demux->out, ES_OUT_GET_ES_STATE,
                      p_stream->p_es, &b_selected );
  
      if( p_stream->b_force_backup )
      {
          bool b_xiph;
          p_stream->i_packets_backup++;
          switch( p_stream->fmt.i_codec )
          {
          case VLC_CODEC_VORBIS:
          case VLC_CODEC_SPEEX:
          case VLC_CODEC_THEORA:
              if( p_stream->i_packets_backup == 3 ) p_stream->b_force_backup = 0;
              b_xiph = true;
              break;
  
          case VLC_CODEC_FLAC:
              if( !p_stream->fmt.audio.i_rate && p_stream->i_packets_backup == 2 )
              {
                  Ogg_ReadFlacHeader( p_demux, p_stream, p_oggpacket );
                  p_stream->b_force_backup = 0;
              }
              else if( p_stream->fmt.audio.i_rate )
              {
                  p_stream->b_force_backup = 0;
                  if( p_oggpacket->bytes >= 9 )
                  {
                      p_oggpacket->packet += 9;
                      p_oggpacket->bytes -= 9;
                  }
              }
              b_xiph = false;
              break;
  
          case VLC_CODEC_KATE:
              if( p_stream->i_packets_backup == p_stream->i_kate_num_headers ) p_stream->b_force_backup = 0;
              b_xiph = true;
              break;
  
          default:
              p_stream->b_force_backup = 0;
              b_xiph = false;
              break;
          }
  
          /* Backup the ogg packet (likely an header packet) */
          if( !b_xiph )
          {
              void *p_org = p_stream->p_headers;
              p_stream->i_headers += p_oggpacket->bytes;
              p_stream->p_headers = realloc( p_stream->p_headers, p_stream->i_headers );
              if( p_stream->p_headers )
              {
                  memcpy( (unsigned char *)p_stream->p_headers + p_stream->i_headers - p_oggpacket->bytes,
                          p_oggpacket->packet, p_stream->i_headers );
              }
              else
              {
  #warning Memory leak
                  p_stream->i_headers = 0;
                  p_stream->p_headers = NULL;
                  free( p_org );
              }
          }
          else if( xiph_AppendHeaders( &p_stream->i_headers, &p_stream->p_headers,
                                       p_oggpacket->bytes, p_oggpacket->packet ) )
          {
              p_stream->i_headers = 0;
              p_stream->p_headers = NULL;
          }
          if( p_stream->i_headers > 0 )
          {
              if( !p_stream->b_force_backup )
              {
                  /* Last header received, commit changes */
                  free( p_stream->fmt.p_extra );
  
                  p_stream->fmt.i_extra = p_stream->i_headers;
                  p_stream->fmt.p_extra = malloc( p_stream->i_headers );
                  if( p_stream->fmt.p_extra )
                      memcpy( p_stream->fmt.p_extra, p_stream->p_headers,
                              p_stream->i_headers );
                  else
                      p_stream->fmt.i_extra = 0;
  
                  if( Ogg_LogicalStreamResetEsFormat( p_demux, p_stream ) )
                      es_out_Control( p_demux->out, ES_OUT_SET_ES_FMT,
                                      p_stream->p_es, &p_stream->fmt );
  
                  if( p_stream->i_headers > 0 )
                      Ogg_ExtractMeta( p_demux, p_stream->fmt.i_codec,
                                       p_stream->p_headers, p_stream->i_headers );
  
                  /* we're not at BOS anymore for this logical stream */
                  p_ogg->i_bos--;
              }
          }
  
          b_selected = false; /* Discard the header packet */
      }
  
      /* Convert the pcr into a pts */
      if( p_stream->fmt.i_codec == VLC_CODEC_VORBIS ||
          p_stream->fmt.i_codec == VLC_CODEC_SPEEX ||
          p_stream->fmt.i_codec == VLC_CODEC_FLAC )
      {
          if( p_stream->i_pcr >= 0 )
          {
              /* This is for streams where the granulepos of the header packets
               * doesn't match these of the data packets (eg. ogg web radios). */
              if( p_stream->i_previous_pcr == 0 &&
                  p_stream->i_pcr  > 3 * DEFAULT_PTS_DELAY )
              {
                  es_out_Control( p_demux->out, ES_OUT_RESET_PCR );
  
                  /* Call the pace control */
                  es_out_Control( p_demux->out, ES_OUT_SET_PCR,
                                  VLC_TS_0 + p_stream->i_pcr );
              }
  
              p_stream->i_previous_pcr = p_stream->i_pcr;
  
              /* The granulepos is the end date of the sample */
              i_pts =  p_stream->i_pcr;
          }
      }
  
      /* Convert the granulepos into the next pcr */
      i_interpolated_pts = p_stream->i_interpolated_pcr;
      Ogg_UpdatePCR( p_stream, p_oggpacket );
  
      /* SPU streams are typically discontinuous, do not mind large gaps */
      if( p_stream->fmt.i_cat != SPU_ES )
      {
          if( p_stream->i_pcr >= 0 )
          {
              /* This is for streams where the granulepos of the header packets
               * doesn't match these of the data packets (eg. ogg web radios). */
              if( p_stream->i_previous_pcr == 0 &&
                  p_stream->i_pcr  > 3 * DEFAULT_PTS_DELAY )
              {
                  es_out_Control( p_demux->out, ES_OUT_RESET_PCR );
  
                  /* Call the pace control */
                  es_out_Control( p_demux->out, ES_OUT_SET_PCR, VLC_TS_0 + p_stream->i_pcr );
              }
          }
      }
  
      if( p_stream->fmt.i_codec != VLC_CODEC_VORBIS &&
          p_stream->fmt.i_codec != VLC_CODEC_SPEEX &&
          p_stream->fmt.i_codec != VLC_CODEC_FLAC &&
          p_stream->i_pcr >= 0 )
      {
          p_stream->i_previous_pcr = p_stream->i_pcr;
  
          /* The granulepos is the start date of the sample */
          i_pts = p_stream->i_pcr;
      }
  
      if( !b_selected )
      {
          /* This stream isn't currently selected so we don't need to decode it,
           * but we did need to store its pcr as it might be selected later on */
          return;
      }
  
      if( p_oggpacket->bytes <= 0 )
          return;
  
      if( !( p_block = block_New( p_demux, p_oggpacket->bytes ) ) ) return;
  
  
      /* may need to preroll video frames after a seek */
      if ( p_stream->i_skip_frames > 0 )
      {
          p_block->i_flags |= BLOCK_FLAG_PREROLL;
          p_stream->i_skip_frames--;
      }
  
  
      /* Normalize PTS */
      if( i_pts == 0 ) i_pts = VLC_TS_0;
      else if( i_pts == -1 && i_interpolated_pts == 0 ) i_pts = VLC_TS_0;
      else if( i_pts == -1 ) i_pts = VLC_TS_INVALID;
  
      if( p_stream->fmt.i_cat == AUDIO_ES )
          p_block->i_dts = p_block->i_pts = i_pts;
      else if( p_stream->fmt.i_cat == SPU_ES )
      {
          p_block->i_dts = p_block->i_pts = i_pts;
          p_block->i_length = 0;
      }
      else if( p_stream->fmt.i_codec == VLC_CODEC_THEORA )
      {
          p_block->i_dts = p_block->i_pts = i_pts;
          if( (p_oggpacket->granulepos & ((1<<p_stream->i_granule_shift)-1)) == 0 )
          {
              p_block->i_flags |= BLOCK_FLAG_TYPE_I;
          }
      }
      else if( p_stream->fmt.i_codec == VLC_CODEC_DIRAC )
      {
          ogg_int64_t dts = p_oggpacket->granulepos >> 31;
          ogg_int64_t delay = (p_oggpacket->granulepos >> 9) & 0x1fff;
  
          uint64_t u_pnum = dts + delay;
  
          p_block->i_dts = p_stream->i_pcr;
          p_block->i_pts = VLC_TS_INVALID;
          /* NB, OggDirac granulepos values are in units of 2*picturerate */
  
          /* granulepos for dirac is possibly broken, this value should be ignored */
          if( -1 != p_oggpacket->granulepos )
              p_block->i_pts = u_pnum * INT64_C(1000000) / p_stream->f_rate / 2;
      }
      else
      {
          p_block->i_dts = i_pts;
          p_block->i_pts = VLC_TS_INVALID;
      }
  
      if( p_stream->fmt.i_codec != VLC_CODEC_VORBIS &&
          p_stream->fmt.i_codec != VLC_CODEC_SPEEX &&
          p_stream->fmt.i_codec != VLC_CODEC_FLAC &&
          p_stream->fmt.i_codec != VLC_CODEC_TARKIN &&
          p_stream->fmt.i_codec != VLC_CODEC_THEORA &&
          p_stream->fmt.i_codec != VLC_CODEC_CMML &&
          p_stream->fmt.i_codec != VLC_CODEC_DIRAC &&
          p_stream->fmt.i_codec != VLC_CODEC_KATE )
      {
          /* We remove the header from the packet */
          i_header_len = (*p_oggpacket->packet & PACKET_LEN_BITS01) >> 6;
          i_header_len |= (*p_oggpacket->packet & PACKET_LEN_BITS2) << 1;
  
          if( p_stream->fmt.i_codec == VLC_CODEC_SUBT)
          {
              /* But with subtitles we need to retrieve the duration first */
              int i, lenbytes = 0;
  
              if( i_header_len > 0 && p_oggpacket->bytes >= i_header_len + 1 )
              {
                  for( i = 0, lenbytes = 0; i < i_header_len; i++ )
                  {
                      lenbytes = lenbytes << 8;
                      lenbytes += *(p_oggpacket->packet + i_header_len - i);
                  }
              }
              if( p_oggpacket->bytes - 1 - i_header_len > 2 ||
                  ( p_oggpacket->packet[i_header_len + 1] != ' ' &&
                    p_oggpacket->packet[i_header_len + 1] != 0 &&
                    p_oggpacket->packet[i_header_len + 1] != '\n' &&
                    p_oggpacket->packet[i_header_len + 1] != '\r' ) )
              {
                  p_block->i_length = (mtime_t)lenbytes * 1000;
              }
          }
  
          i_header_len++;
          if( p_block->i_buffer >= (unsigned int)i_header_len )
              p_block->i_buffer -= i_header_len;
          else
              p_block->i_buffer = 0;
      }
  
      if( p_stream->fmt.i_codec == VLC_CODEC_TARKIN )
      {
          /* FIXME: the biggest hack I've ever done */
          msg_Warn( p_demux, "tarkin pts: %"PRId64", granule: %"PRId64,
                    p_block->i_pts, p_block->i_dts );
          msleep(10000);
      }
  
      memcpy( p_block->p_buffer, p_oggpacket->packet + i_header_len,
              p_oggpacket->bytes - i_header_len );
  
      es_out_Send( p_demux->out, p_stream->p_es, p_block );
  }
  
  /****************************************************************************
   * Ogg_FindLogicalStreams: Find the logical streams embedded in the physical
   *                         stream and fill p_ogg.
   *****************************************************************************
   * The initial page of a logical stream is marked as a 'bos' page.
   * Furthermore, the Ogg specification mandates that grouped bitstreams begin
   * together and all of the initial pages must appear before any data pages.
   *
   * On success this function returns VLC_SUCCESS.
   ****************************************************************************/
  static int Ogg_FindLogicalStreams( demux_t *p_demux )
  {
      demux_sys_t *p_ogg = p_demux->p_sys  ;
      ogg_packet oggpacket;
      int i_stream;
  
      p_ogg->i_total_length = stream_Size ( p_demux->s );
      msg_Dbg( p_demux, "File length is %"PRId64" bytes", p_ogg->i_total_length );
  
  
      while( Ogg_ReadPage( p_demux, &p_ogg->current_page ) == VLC_SUCCESS )
      {
  
          if( ogg_page_bos( &p_ogg->current_page ) )
          {
  
              /* All is wonderful in our fine fine little world.
               * We found the beginning of our first logical stream. */
              while( ogg_page_bos( &p_ogg->current_page ) )
              {
                  logical_stream_t *p_stream;
  
                  p_stream = malloc( sizeof(logical_stream_t) );
                  if( !p_stream )
                      return VLC_ENOMEM;
  
                  TAB_APPEND( p_ogg->i_streams, p_ogg->pp_stream, p_stream );
  
                  memset( p_stream, 0, sizeof(logical_stream_t) );
                  p_stream->p_headers = 0;
                  p_stream->i_secondary_header_packets = 0;
  
                  p_stream->i_keyframe_offset = 0;
                  p_stream->i_skip_frames = 0;
  
                  p_stream->i_data_start = 0;
  
                  es_format_Init( &p_stream->fmt, 0, 0 );
                  es_format_Init( &p_stream->fmt_old, 0, 0 );
  
                  /* Setup the logical stream */
                  p_stream->i_serial_no = ogg_page_serialno( &p_ogg->current_page );
                  ogg_stream_init( &p_stream->os, p_stream->i_serial_no );
  
                  /* Extract the initial header from the first page and verify
                   * the codec type of this Ogg bitstream */
                  if( ogg_stream_pagein( &p_stream->os, &p_ogg->current_page ) < 0 )
                  {
                      /* error. stream version mismatch perhaps */
                      msg_Err( p_demux, "error reading first page of "
                               "Ogg bitstream data" );
                      return VLC_EGENERIC;
                  }
  
                  /* FIXME: check return value */
                  ogg_stream_packetpeek( &p_stream->os, &oggpacket );
  
                  /* Check for Vorbis header */
                  if( oggpacket.bytes >= 7 &&
                      ! memcmp( oggpacket.packet, "\x01vorbis", 7 ) )
                  {
                      Ogg_ReadVorbisHeader( p_stream, &oggpacket );
                      msg_Dbg( p_demux, "found vorbis header" );
                  }
                  /* Check for Speex header */
                  else if( oggpacket.bytes >= 5 &&
                      ! memcmp( oggpacket.packet, "Speex", 5 ) )
                  {
                      Ogg_ReadSpeexHeader( p_stream, &oggpacket );
                      msg_Dbg( p_demux, "found speex header, channels: %i, "
                               "rate: %i,  bitrate: %i",
                               p_stream->fmt.audio.i_channels,
                               (int)p_stream->f_rate, p_stream->fmt.i_bitrate );
                  }
                  /* Check for Flac header (< version 1.1.1) */
                  else if( oggpacket.bytes >= 4 &&
                      ! memcmp( oggpacket.packet, "fLaC", 4 ) )
                  {
                      msg_Dbg( p_demux, "found FLAC header" );
  
                      /* Grrrr!!!! Did they really have to put all the
                       * important info in the second header packet!!!
                       * (STREAMINFO metadata is in the following packet) */
                      p_stream->b_force_backup = 1;
  
                      p_stream->fmt.i_cat = AUDIO_ES;
                      p_stream->fmt.i_codec = VLC_CODEC_FLAC;
                  }
                  /* Check for Flac header (>= version 1.1.1) */
                  else if( oggpacket.bytes >= 13 && oggpacket.packet[0] ==0x7F &&
                      ! memcmp( &oggpacket.packet[1], "FLAC", 4 ) &&
                      ! memcmp( &oggpacket.packet[9], "fLaC", 4 ) )
                  {
                      int i_packets = ((int)oggpacket.packet[7]) << 8 |
                          oggpacket.packet[8];
                      msg_Dbg( p_demux, "found FLAC header version %i.%i "
                               "(%i header packets)",
                               oggpacket.packet[5], oggpacket.packet[6],
                               i_packets );
  
                      p_stream->b_force_backup = 1;
  
                      p_stream->fmt.i_cat = AUDIO_ES;
                      p_stream->fmt.i_codec = VLC_CODEC_FLAC;
                      oggpacket.packet += 13; oggpacket.bytes -= 13;
                      Ogg_ReadFlacHeader( p_demux, p_stream, &oggpacket );
                  }
                  /* Check for Theora header */
                  else if( oggpacket.bytes >= 7 &&
                           ! memcmp( oggpacket.packet, "\x80theora", 7 ) )
                  {
                      Ogg_ReadTheoraHeader( p_stream, &oggpacket );
  
                      msg_Dbg( p_demux,
                               "found theora header, bitrate: %i, rate: %f",
                               p_stream->fmt.i_bitrate, p_stream->f_rate );
                  }
                  /* Check for Dirac header */
                  else if( ( oggpacket.bytes >= 5 &&
                             ! memcmp( oggpacket.packet, "BBCD\x00", 5 ) ) ||
                           ( oggpacket.bytes >= 9 &&
                             ! memcmp( oggpacket.packet, "KW-DIRAC\x00", 9 ) ) )
                  {
                      if( Ogg_ReadDiracHeader( p_stream, &oggpacket ) )
                          msg_Dbg( p_demux, "found dirac header" );
                      else
                      {
                          msg_Warn( p_demux, "found dirac header isn't decodable" );
                          free( p_stream );
                          p_ogg->i_streams--;
                      }
                  }
                  /* Check for Tarkin header */
                  else if( oggpacket.bytes >= 7 &&
                           ! memcmp( &oggpacket.packet[1], "tarkin", 6 ) )
                  {
                      oggpack_buffer opb;
  
                      msg_Dbg( p_demux, "found tarkin header" );
                      p_stream->fmt.i_cat = VIDEO_ES;
                      p_stream->fmt.i_codec = VLC_CODEC_TARKIN;
  
                      /* Cheat and get additionnal info ;) */
                      oggpack_readinit( &opb, oggpacket.packet, oggpacket.bytes);
                      oggpack_adv( &opb, 88 );
                      oggpack_adv( &opb, 104 );
                      p_stream->fmt.i_bitrate = oggpack_read( &opb, 32 );
                      p_stream->f_rate = 2; /* FIXME */
                      msg_Dbg( p_demux,
                               "found tarkin header, bitrate: %i, rate: %f",
                               p_stream->fmt.i_bitrate, p_stream->f_rate );
                  }
                  /* Check for Annodex header */
                  else if( oggpacket.bytes >= 7 &&
                           ! memcmp( oggpacket.packet, "Annodex", 7 ) )
                  {
                      Ogg_ReadAnnodexHeader( VLC_OBJECT(p_demux), p_stream,
                                             &oggpacket );
                      /* kill annodex track */
                      free( p_stream );
                      p_ogg->i_streams--;
                  }
                  /* Check for Annodex header */
                  else if( oggpacket.bytes >= 7 &&
                           ! memcmp( oggpacket.packet, "AnxData", 7 ) )
                  {
                      Ogg_ReadAnnodexHeader( VLC_OBJECT(p_demux), p_stream,
                                             &oggpacket );
                  }
                  /* Check for Kate header */
                  else if( oggpacket.bytes >= 8 &&
                      ! memcmp( &oggpacket.packet[1], "kate\0\0\0", 7 ) )
                  {
                      Ogg_ReadKateHeader( p_stream, &oggpacket );
                      msg_Dbg( p_demux, "found kate header" );
                  }
                  else if( oggpacket.bytes >= 142 &&
                           !memcmp( &oggpacket.packet[1],
                                     "Direct Show Samples embedded in Ogg", 35 ))
                  {
                      /* Old header type */
  
                      /* Check for video header (old format) */
                      if( GetDWLE((oggpacket.packet+96)) == 0x05589f80 &&
                          oggpacket.bytes >= 184 )
                      {
                          p_stream->fmt.i_cat = VIDEO_ES;
                          p_stream->fmt.i_codec =
                              VLC_FOURCC( oggpacket.packet[68],
                                          oggpacket.packet[69],
                                          oggpacket.packet[70],
                                          oggpacket.packet[71] );
                          msg_Dbg( p_demux, "found video header of type: %.4s",
                                   (char *)&p_stream->fmt.i_codec );
  
                          p_stream->fmt.video.i_frame_rate = 10000000;
                          p_stream->fmt.video.i_frame_rate_base =
                              GetQWLE((oggpacket.packet+164));
                          p_stream->f_rate = 10000000.0 /
                              GetQWLE((oggpacket.packet+164));
                          p_stream->fmt.video.i_bits_per_pixel =
                              GetWLE((oggpacket.packet+182));
                          if( !p_stream->fmt.video.i_bits_per_pixel )
                              /* hack, FIXME */
                              p_stream->fmt.video.i_bits_per_pixel = 24;
                          p_stream->fmt.video.i_width =
                              GetDWLE((oggpacket.packet+176));
                          p_stream->fmt.video.i_height =
                              GetDWLE((oggpacket.packet+180));
  
                          msg_Dbg( p_demux,
                                   "fps: %f, width:%i; height:%i, bitcount:%i",
                                   p_stream->f_rate,
                                   p_stream->fmt.video.i_width,
                                   p_stream->fmt.video.i_height,
                                   p_stream->fmt.video.i_bits_per_pixel);
  
                      }
                      /* Check for audio header (old format) */
                      else if( GetDWLE((oggpacket.packet+96)) == 0x05589F81 )
                      {
                          int i_extra_size;
                          unsigned int i_format_tag;
  
                          p_stream->fmt.i_cat = AUDIO_ES;
  
                          i_extra_size = GetWLE((oggpacket.packet+140));
                          if( i_extra_size > 0 && i_extra_size < oggpacket.bytes - 142 )
                          {
                              p_stream->fmt.i_extra = i_extra_size;
                              p_stream->fmt.p_extra = malloc( i_extra_size );
                              if( p_stream->fmt.p_extra )
                                  memcpy( p_stream->fmt.p_extra,
                                          oggpacket.packet + 142, i_extra_size );
                              else
                                  p_stream->fmt.i_extra = 0;
                          }
  
                          i_format_tag = GetWLE((oggpacket.packet+124));
                          p_stream->fmt.audio.i_channels =
                              GetWLE((oggpacket.packet+126));
                          p_stream->f_rate = p_stream->fmt.audio.i_rate =
                              GetDWLE((oggpacket.packet+128));
                          p_stream->fmt.i_bitrate =
                              GetDWLE((oggpacket.packet+132)) * 8;
                          p_stream->fmt.audio.i_blockalign =
                              GetWLE((oggpacket.packet+136));
                          p_stream->fmt.audio.i_bitspersample =
                              GetWLE((oggpacket.packet+138));
  
                          wf_tag_to_fourcc( i_format_tag,
                                            &p_stream->fmt.i_codec, 0 );
  
                          if( p_stream->fmt.i_codec ==
                              VLC_FOURCC('u','n','d','f') )
                          {
                              p_stream->fmt.i_codec = VLC_FOURCC( 'm', 's',
                                  ( i_format_tag >> 8 ) & 0xff,
                                  i_format_tag & 0xff );
                          }
  
                          msg_Dbg( p_demux, "found audio header of type: %.4s",
                                   (char *)&p_stream->fmt.i_codec );
                          msg_Dbg( p_demux, "audio:0x%4.4x channels:%d %dHz "
                                   "%dbits/sample %dkb/s",
                                   i_format_tag,
                                   p_stream->fmt.audio.i_channels,
                                   p_stream->fmt.audio.i_rate,
                                   p_stream->fmt.audio.i_bitspersample,
                                   p_stream->fmt.i_bitrate / 1024 );
  
                      }
                      else
                      {
                          msg_Dbg( p_demux, "stream %d has an old header "
                              "but is of an unknown type", p_ogg->i_streams-1 );
                          free( p_stream );
                          p_ogg->i_streams--;
                      }
                  }
                  else if( (*oggpacket.packet & PACKET_TYPE_BITS ) == PACKET_TYPE_HEADER &&
                           oggpacket.bytes >= 44+1 )
                  {
                      stream_header_t tmp;
                      stream_header_t *st = &tmp;
  
                      memcpy( st->streamtype, &oggpacket.packet[1+0], 8 );
                      memcpy( st->subtype, &oggpacket.packet[1+8], 4 );
                      st->size = GetDWLE( &oggpacket.packet[1+12] );
                      st->time_unit = GetQWLE( &oggpacket.packet[1+16] );
                      st->samples_per_unit = GetQWLE( &oggpacket.packet[1+24] );
                      st->default_len = GetDWLE( &oggpacket.packet[1+32] );
                      st->buffersize = GetDWLE( &oggpacket.packet[1+36] );
                      st->bits_per_sample = GetWLE( &oggpacket.packet[1+40] ); // (padding 2)
  
                      /* Check for video header (new format) */
                      if( !strncmp( st->streamtype, "video", 5 ) &&
                          oggpacket.bytes >= 52+1 )
                      {
                          st->sh.video.width = GetDWLE( &oggpacket.packet[1+44] );
                          st->sh.video.height = GetDWLE( &oggpacket.packet[1+48] );
  
                          p_stream->fmt.i_cat = VIDEO_ES;
  
                          /* We need to get rid of the header packet */
                          ogg_stream_packetout( &p_stream->os, &oggpacket );
  
                          p_stream->fmt.i_codec =
                              VLC_FOURCC( st->subtype[0], st->subtype[1],
                                          st->subtype[2], st->subtype[3] );
                          msg_Dbg( p_demux, "found video header of type: %.4s",
                                   (char *)&p_stream->fmt.i_codec );
  
                          p_stream->fmt.video.i_frame_rate = 10000000;
                          p_stream->fmt.video.i_frame_rate_base = st->time_unit;
                          if( st->time_unit <= 0 )
                              st->time_unit = 400000;
                          p_stream->f_rate = 10000000.0 / st->time_unit;
                          p_stream->fmt.video.i_bits_per_pixel = st->bits_per_sample;
                          p_stream->fmt.video.i_width = st->sh.video.width;
                          p_stream->fmt.video.i_height = st->sh.video.height;
  
                          msg_Dbg( p_demux,
                                   "fps: %f, width:%i; height:%i, bitcount:%i",
                                   p_stream->f_rate,
                                   p_stream->fmt.video.i_width,
                                   p_stream->fmt.video.i_height,
                                   p_stream->fmt.video.i_bits_per_pixel );
                      }
                      /* Check for audio header (new format) */
                      else if( !strncmp( st->streamtype, "audio", 5 ) &&
                               oggpacket.bytes >= 56+1 )
                      {
                          char p_buffer[5];
                          int i_extra_size;
                          int i_format_tag;
  
                          st->sh.audio.channels = GetWLE( &oggpacket.packet[1+44] );
                          st->sh.audio.blockalign = GetWLE( &oggpacket.packet[1+48] );
                          st->sh.audio.avgbytespersec = GetDWLE( &oggpacket.packet[1+52] );
  
                          p_stream->fmt.i_cat = AUDIO_ES;
  
                          /* We need to get rid of the header packet */
                          ogg_stream_packetout( &p_stream->os, &oggpacket );
  
                          i_extra_size = st->size - 56;
  
                          if( i_extra_size > 0 &&
                              i_extra_size < oggpacket.bytes - 1 - 56 )
                          {
                              p_stream->fmt.i_extra = i_extra_size;
                              p_stream->fmt.p_extra = malloc( p_stream->fmt.i_extra );
                              if( p_stream->fmt.p_extra )
                                  memcpy( p_stream->fmt.p_extra, st + 1,
                                          p_stream->fmt.i_extra );
                              else
                                  p_stream->fmt.i_extra = 0;
                          }
  
                          memcpy( p_buffer, st->subtype, 4 );
                          p_buffer[4] = '\0';
                          i_format_tag = strtol(p_buffer,NULL,16);
                          p_stream->fmt.audio.i_channels = st->sh.audio.channels;
                          if( st->time_unit <= 0 )
                              st->time_unit = 10000000;
                          p_stream->f_rate = p_stream->fmt.audio.i_rate = st->samples_per_unit * 10000000 / st->time_unit;
                          p_stream->fmt.i_bitrate = st->sh.audio.avgbytespersec * 8;
                          p_stream->fmt.audio.i_blockalign = st->sh.audio.blockalign;
                          p_stream->fmt.audio.i_bitspersample = st->bits_per_sample;
  
                          wf_tag_to_fourcc( i_format_tag,
                                            &p_stream->fmt.i_codec, 0 );
  
                          if( p_stream->fmt.i_codec ==
                              VLC_FOURCC('u','n','d','f') )
                          {
                              p_stream->fmt.i_codec = VLC_FOURCC( 'm', 's',
                                  ( i_format_tag >> 8 ) & 0xff,
                                  i_format_tag & 0xff );
                          }
  
                          msg_Dbg( p_demux, "found audio header of type: %.4s",
                                   (char *)&p_stream->fmt.i_codec );
                          msg_Dbg( p_demux, "audio:0x%4.4x channels:%d %dHz "
                                   "%dbits/sample %dkb/s",
                                   i_format_tag,
                                   p_stream->fmt.audio.i_channels,
                                   p_stream->fmt.audio.i_rate,
                                   p_stream->fmt.audio.i_bitspersample,
                                   p_stream->fmt.i_bitrate / 1024 );
                      }
                      /* Check for text (subtitles) header */
                      else if( !strncmp(st->streamtype, "text", 4) )
                      {
                          /* We need to get rid of the header packet */
                          ogg_stream_packetout( &p_stream->os, &oggpacket );
  
                          msg_Dbg( p_demux, "found text subtitles header" );
                          p_stream->fmt.i_cat = SPU_ES;
                          p_stream->fmt.i_codec = VLC_CODEC_SUBT;
                          p_stream->f_rate = 1000; /* granulepos is in millisec */
                      }
                      else
                      {
                          msg_Dbg( p_demux, "stream %d has a header marker "
                              "but is of an unknown type", p_ogg->i_streams-1 );
                          free( p_stream );
                          p_ogg->i_streams--;
                      }
                  }
                  else if( oggpacket.bytes >= 7 &&
                               ! memcmp( oggpacket.packet, "fishead", 7 ) )
  
                  {
                      /* Skeleton */
                      msg_Dbg( p_demux, "stream %d is a skeleton",
                                  p_ogg->i_streams-1 );
                      /* FIXME: https://trac.videolan.org/vlc/ticket/1412 */
                  }
                  else
                  {
                      msg_Dbg( p_demux, "stream %d is of unknown type",
                               p_ogg->i_streams-1 );
                      free( p_stream );
                      p_ogg->i_streams--;
                  }
  
                  if( Ogg_ReadPage( p_demux, &p_ogg->current_page ) != VLC_SUCCESS )
                      return VLC_EGENERIC;
              }
  
              /* we'll need to get all headers for all of those streams
                 that we have to backup headers for */
              p_ogg->i_bos = 0;
              for( i_stream = 0; i_stream < p_ogg->i_streams; i_stream++ )
              {
                  if( p_ogg->pp_stream[i_stream]->b_force_backup )
                      p_ogg->i_bos++;
              }
  
  
              /* This is the first data page, which means we are now finished
               * with the initial pages. We just need to store it in the relevant
               * bitstream. */
              for( i_stream = 0; i_stream < p_ogg->i_streams; i_stream++ )
              {
                  if( ogg_stream_pagein( &p_ogg->pp_stream[i_stream]->os,
                                         &p_ogg->current_page ) == 0 )
                  {
                      p_ogg->b_page_waiting = true;
                      break;
                  }
              }
  
              return VLC_SUCCESS;
          }
      }
  
      return VLC_EGENERIC;
  }
  
  /****************************************************************************
   * Ogg_BeginningOfStream: Look for Beginning of Stream ogg pages and add
   *                        Elementary streams.
   ****************************************************************************/
  static int Ogg_BeginningOfStream( demux_t *p_demux )
  {
      demux_sys_t *p_ogg = p_demux->p_sys  ;
      logical_stream_t *p_old_stream = p_ogg->p_old_stream;
      int i_stream;
  
      /* Find the logical streams embedded in the physical stream and
       * initialize our p_ogg structure. */
      if( Ogg_FindLogicalStreams( p_demux ) != VLC_SUCCESS )
      {
          msg_Warn( p_demux, "couldn't find any ogg logical stream" );
          return VLC_EGENERIC;
      }
  
      p_ogg->i_bitrate = 0;
  
      for( i_stream = 0 ; i_stream < p_ogg->i_streams; i_stream++ )
      {
          logical_stream_t *p_stream = p_ogg->pp_stream[i_stream];
  
          p_stream->p_es = NULL;
  
          /* initialise kframe index */
          p_stream->idx=NULL;
  
          /* Try first to reuse an old ES */
          if( p_old_stream &&
              p_old_stream->fmt.i_cat == p_stream->fmt.i_cat &&
              p_old_stream->fmt.i_codec == p_stream->fmt.i_codec )
          {
              msg_Dbg( p_demux, "will reuse old stream to avoid glitch" );
  
              p_stream->p_es = p_old_stream->p_es;
              es_format_Copy( &p_stream->fmt_old, &p_old_stream->fmt );
  
              p_old_stream->p_es = NULL;
              p_old_stream = NULL;
          }
  
          if( !p_stream->p_es )
          {
              /* Better be safe than sorry when possible with ogm */
              if( p_stream->fmt.i_codec == VLC_CODEC_MPGA ||
                  p_stream->fmt.i_codec == VLC_CODEC_A52 )
                  p_stream->fmt.b_packetized = false;
  
              p_stream->p_es = es_out_Add( p_demux->out, &p_stream->fmt );
          }
  
          // TODO: something to do here ?
          if( p_stream->fmt.i_codec == VLC_CODEC_CMML )
          {
              /* Set the CMML stream active */
              es_out_Control( p_demux->out, ES_OUT_SET_ES, p_stream->p_es );
          }
  
          p_ogg->i_bitrate += p_stream->fmt.i_bitrate;
  
          p_stream->i_pcr = p_stream->i_previous_pcr =
              p_stream->i_interpolated_pcr = -1;
          p_stream->b_reinit = false;
      }
  
      if( p_ogg->p_old_stream )
      {
          if( p_ogg->p_old_stream->p_es )
              msg_Dbg( p_demux, "old stream not reused" );
          Ogg_LogicalStreamDelete( p_demux, p_ogg->p_old_stream );
          p_ogg->p_old_stream = NULL;
      }
  
  
      /* get total frame count for video stream; we will need this for seeking */
      p_ogg->i_total_frames = 0;
  
      return VLC_SUCCESS;
  }
  
  /****************************************************************************
   * Ogg_EndOfStream: clean up the ES when an End of Stream is detected.
   ****************************************************************************/
  static void Ogg_EndOfStream( demux_t *p_demux )
  {
      demux_sys_t *p_ogg = p_demux->p_sys  ;
      int i_stream;
  
      for( i_stream = 0 ; i_stream < p_ogg->i_streams; i_stream++ )
          Ogg_LogicalStreamDelete( p_demux, p_ogg->pp_stream[i_stream] );
      free( p_ogg->pp_stream );
  
      /* Reinit p_ogg */
      p_ogg->i_bitrate = 0;
      p_ogg->i_streams = 0;
      p_ogg->pp_stream = NULL;
  
      /* */
      if( p_ogg->p_meta )
          vlc_meta_Delete( p_ogg->p_meta );
      p_ogg->p_meta = NULL;
  }
  
  /**
   * This function delete and release all data associated to a logical_stream_t
   */
  static void Ogg_LogicalStreamDelete( demux_t *p_demux, logical_stream_t *p_stream )
  {
      if( p_stream->p_es )
          es_out_Del( p_demux->out, p_stream->p_es );
  
      ogg_stream_clear( &p_stream->os );
      free( p_stream->p_headers );
  
      es_format_Clean( &p_stream->fmt_old );
      es_format_Clean( &p_stream->fmt );
  
      if ( p_stream->idx != NULL)
      {
          oggseek_index_entries_free( p_stream->idx );
      }
  
      free( p_stream );
  }
  /**
   * This function check if a we need to reset a decoder in case we are
   * reusing an old ES
   */
  static bool Ogg_IsVorbisFormatCompatible( const es_format_t *p_new, const es_format_t *p_old )
  {
      unsigned pi_new_size[XIPH_MAX_HEADER_COUNT];
      void     *pp_new_data[XIPH_MAX_HEADER_COUNT];
      unsigned i_new_count;
      if( xiph_SplitHeaders(pi_new_size, pp_new_data, &i_new_count, p_new->i_extra, p_new->p_extra ) )
          i_new_count = 0;
  
      unsigned pi_old_size[XIPH_MAX_HEADER_COUNT];
      void     *pp_old_data[XIPH_MAX_HEADER_COUNT];
      unsigned i_old_count;
      if( xiph_SplitHeaders(pi_old_size, pp_old_data, &i_old_count, p_old->i_extra, p_old->p_extra ) )
          i_old_count = 0;
  
      bool b_match = i_new_count == i_old_count;
      for( unsigned i = 0; i < i_new_count && b_match; i++ )
      {
          /* Ignore vorbis comment */
          if( i == 1 )
              continue;
          if( pi_new_size[i] != pi_old_size[i] ||
              memcmp( pp_new_data[i], pp_old_data[i], pi_new_size[i] ) )
              b_match = false;
      }
  
      for( unsigned i = 0; i < i_new_count; i++ )
          free( pp_new_data[i] );
      for( unsigned i = 0; i < i_old_count; i++ )
          free( pp_old_data[i] );
      return b_match;
  }
  static bool Ogg_LogicalStreamResetEsFormat( demux_t *p_demux, logical_stream_t *p_stream )
  {
      bool b_compatible = false;
      if( !p_stream->fmt_old.i_cat || !p_stream->fmt_old.i_codec )
          return true;
  
      /* Only vorbis is supported */
      if( p_stream->fmt.i_codec == VLC_CODEC_VORBIS )
          b_compatible = Ogg_IsVorbisFormatCompatible( &p_stream->fmt, &p_stream->fmt_old );
  
      if( !b_compatible )
          msg_Warn( p_demux, "cannot reuse old stream, resetting the decoder" );
  
      return !b_compatible;
  }
  static void Ogg_ExtractXiphMeta( demux_t *p_demux, const void *p_headers, unsigned i_headers, unsigned i_skip )
  {
      demux_sys_t *p_ogg = p_demux->p_sys;
  
      unsigned pi_size[XIPH_MAX_HEADER_COUNT];
      void     *pp_data[XIPH_MAX_HEADER_COUNT];
      unsigned i_count;
      if( xiph_SplitHeaders( pi_size, pp_data, &i_count, i_headers, p_headers ) )
          return;
  
      /* TODO how to handle multiple comments properly ? */
      if( i_count >= 2 && pi_size[1] > i_skip )
          vorbis_ParseComment( &p_ogg->p_meta, (uint8_t*)pp_data[1] + i_skip, pi_size[1] - i_skip );
  
      for( unsigned i = 0; i < i_count; i++ )
          free( pp_data[i] );
  }
  static void Ogg_ExtractMeta( demux_t *p_demux, vlc_fourcc_t i_codec, const uint8_t *p_headers, int i_headers )
  {
      demux_sys_t *p_ogg = p_demux->p_sys;
  
      switch( i_codec )
      {
      /* 3 headers with the 2° one being the comments */
      case VLC_CODEC_VORBIS:
          Ogg_ExtractXiphMeta( p_demux, p_headers, i_headers, 1+6 );
          break;
      case VLC_CODEC_THEORA:
          Ogg_ExtractXiphMeta( p_demux, p_headers, i_headers, 1+6 );
          break;
      case VLC_CODEC_SPEEX:
          Ogg_ExtractXiphMeta( p_demux, p_headers, i_headers, 0 );
          break;
  
      /* N headers with the 2° one being the comments */
      case VLC_CODEC_KATE:
          /* 1 byte for header type, 7 bytes for magic, 1 reserved zero byte */
          Ogg_ExtractXiphMeta( p_demux, p_headers, i_headers, 1+7+1 );
          break;
  
      /* TODO */
      case VLC_CODEC_FLAC:
          msg_Warn( p_demux, "Ogg_ExtractMeta does not support %4.4s", (const char*)&i_codec );
          break;
  
      /* No meta data */
      case VLC_CODEC_CMML: /* CMML is XML text, doesn't have Vorbis comments */
      case VLC_CODEC_DIRAC:
      default:
          break;
      }
      if( p_ogg->p_meta )
          p_demux->info.i_update |= INPUT_UPDATE_META;
  }
  
  static void Ogg_ReadTheoraHeader( logical_stream_t *p_stream,
                                    ogg_packet *p_oggpacket )
  {
      bs_t bitstream;
      int i_fps_numerator;
      int i_fps_denominator;
      int i_keyframe_frequency_force;
      int i_major;
      int i_minor;
      int i_subminor;
      int i_version;
  
      p_stream->fmt.i_cat = VIDEO_ES;
      p_stream->fmt.i_codec = VLC_CODEC_THEORA;
  
      /* Signal that we want to keep a backup of the theora
       * stream headers. They will be used when switching between
       * audio streams. */
      p_stream->b_force_backup = 1;
  
      /* Cheat and get additionnal info ;) */
      bs_init( &bitstream, p_oggpacket->packet, p_oggpacket->bytes );
      bs_skip( &bitstream, 56 );
  
      i_major = bs_read( &bitstream, 8 ); /* major version num */
      i_minor = bs_read( &bitstream, 8 ); /* minor version num */
      i_subminor = bs_read( &bitstream, 8 ); /* subminor version num */
  
      bs_read( &bitstream, 16 ) /*<< 4*/; /* width */
      bs_read( &bitstream, 16 ) /*<< 4*/; /* height */
      bs_read( &bitstream, 24 ); /* frame width */
      bs_read( &bitstream, 24 ); /* frame height */
      bs_read( &bitstream, 8 ); /* x offset */
      bs_read( &bitstream, 8 ); /* y offset */
  
      i_fps_numerator = bs_read( &bitstream, 32 );
      i_fps_denominator = bs_read( &bitstream, 32 );
      bs_read( &bitstream, 24 ); /* aspect_numerator */
      bs_read( &bitstream, 24 ); /* aspect_denominator */
  
      p_stream->fmt.video.i_frame_rate = i_fps_numerator;
      p_stream->fmt.video.i_frame_rate_base = i_fps_denominator;
  
      bs_read( &bitstream, 8 ); /* colorspace */
      p_stream->fmt.i_bitrate = bs_read( &bitstream, 24 );
      bs_read( &bitstream, 6 ); /* quality */
  
      i_keyframe_frequency_force = 1 << bs_read( &bitstream, 5 );
  
      /* granule_shift = i_log( frequency_force -1 ) */
      p_stream->i_granule_shift = 0;
      i_keyframe_frequency_force--;
      while( i_keyframe_frequency_force )
      {
          p_stream->i_granule_shift++;
          i_keyframe_frequency_force >>= 1;
      }
  
      i_version = i_major * 1000000 + i_minor * 1000 + i_subminor;
      p_stream->i_keyframe_offset = 0;
  
      if ( i_version >= 3002001 )
      {
          p_stream->i_keyframe_offset = 1;
      }
  
      p_stream->f_rate = ((float)i_fps_numerator) / i_fps_denominator;
  }
  
  static void Ogg_ReadVorbisHeader( logical_stream_t *p_stream,
                                    ogg_packet *p_oggpacket )
  {
      oggpack_buffer opb;
  
      p_stream->fmt.i_cat = AUDIO_ES;
      p_stream->fmt.i_codec = VLC_CODEC_VORBIS;
  
      /* Signal that we want to keep a backup of the vorbis
       * stream headers. They will be used when switching between
       * audio streams. */
      p_stream->b_force_backup = 1;
  
      /* Cheat and get additionnal info ;) */
      oggpack_readinit( &opb, p_oggpacket->packet, p_oggpacket->bytes);
      oggpack_adv( &opb, 88 );
      p_stream->fmt.audio.i_channels = oggpack_read( &opb, 8 );
      p_stream->f_rate = p_stream->fmt.audio.i_rate =
          oggpack_read( &opb, 32 );
      oggpack_adv( &opb, 32 );
      p_stream->fmt.i_bitrate = oggpack_read( &opb, 32 );
  }
  
  static void Ogg_ReadSpeexHeader( logical_stream_t *p_stream,
                                   ogg_packet *p_oggpacket )
  {
      oggpack_buffer opb;
  
      p_stream->fmt.i_cat = AUDIO_ES;
      p_stream->fmt.i_codec = VLC_CODEC_SPEEX;
  
      /* Signal that we want to keep a backup of the speex
       * stream headers. They will be used when switching between
       * audio streams. */
      p_stream->b_force_backup = 1;
  
      /* Cheat and get additionnal info ;) */
      oggpack_readinit( &opb, p_oggpacket->packet, p_oggpacket->bytes);
      oggpack_adv( &opb, 224 );
      oggpack_adv( &opb, 32 ); /* speex_version_id */
      oggpack_adv( &opb, 32 ); /* header_size */
      p_stream->f_rate = p_stream->fmt.audio.i_rate = oggpack_read( &opb, 32 );
      oggpack_adv( &opb, 32 ); /* mode */
      oggpack_adv( &opb, 32 ); /* mode_bitstream_version */
      p_stream->fmt.audio.i_channels = oggpack_read( &opb, 32 );
      p_stream->fmt.i_bitrate = oggpack_read( &opb, 32 );
  }
  
  static void Ogg_ReadFlacHeader( demux_t *p_demux, logical_stream_t *p_stream,
                                  ogg_packet *p_oggpacket )
  {
      /* Parse the STREAMINFO metadata */
      bs_t s;
  
      bs_init( &s, p_oggpacket->packet, p_oggpacket->bytes );
  
      bs_read( &s, 1 );
      if( bs_read( &s, 7 ) == 0 )
      {
          if( bs_read( &s, 24 ) >= 34 /*size STREAMINFO*/ )
          {
              bs_skip( &s, 80 );
              p_stream->f_rate = p_stream->fmt.audio.i_rate = bs_read( &s, 20 );
              p_stream->fmt.audio.i_channels = bs_read( &s, 3 ) + 1;
  
              msg_Dbg( p_demux, "FLAC header, channels: %i, rate: %i",
                       p_stream->fmt.audio.i_channels, (int)p_stream->f_rate );
          }
          else
          {
              msg_Dbg( p_demux, "FLAC STREAMINFO metadata too short" );
          }
  
          /* Fake this as the last metadata block */
          *((uint8_t*)p_oggpacket->packet) |= 0x80;
      }
      else
      {
          /* This ain't a STREAMINFO metadata */
          msg_Dbg( p_demux, "Invalid FLAC STREAMINFO metadata" );
      }
  }
  
  static void Ogg_ReadKateHeader( logical_stream_t *p_stream,
                                  ogg_packet *p_oggpacket )
  {
      oggpack_buffer opb;
      int32_t gnum;
      int32_t gden;
      int n;
      char *psz_desc;
  
      p_stream->fmt.i_cat = SPU_ES;
      p_stream->fmt.i_codec = VLC_CODEC_KATE;
  
      /* Signal that we want to keep a backup of the kate
       * stream headers. They will be used when switching between
       * kate streams. */
      p_stream->b_force_backup = 1;
  
      /* Cheat and get additionnal info ;) */
      oggpack_readinit( &opb, p_oggpacket->packet, p_oggpacket->bytes);
      oggpack_adv( &opb, 11*8 ); /* packet type, kate magic, version */
      p_stream->i_kate_num_headers = oggpack_read( &opb, 8 );
      oggpack_adv( &opb, 3*8 );
      p_stream->i_granule_shift = oggpack_read( &opb, 8 );
      oggpack_adv( &opb, 8*8 ); /* reserved */
      gnum = oggpack_read( &opb, 32 );
      gden = oggpack_read( &opb, 32 );
      p_stream->f_rate = (double)gnum/gden;
  
      p_stream->fmt.psz_language = malloc(16);
      if( p_stream->fmt.psz_language )
      {
          for( n = 0; n < 16; n++ )
              p_stream->fmt.psz_language[n] = oggpack_read(&opb,8);
          p_stream->fmt.psz_language[15] = 0; /* just in case */
      }
      else
      {
          for( n = 0; n < 16; n++ )
              oggpack_read(&opb,8);
      }
      p_stream->fmt.psz_description = malloc(16);
      if( p_stream->fmt.psz_description )
      {
          for( n = 0; n < 16; n++ )
              p_stream->fmt.psz_description[n] = oggpack_read(&opb,8);
          p_stream->fmt.psz_description[15] = 0; /* just in case */
  
          /* Now find a localized user readable description for this category */
          psz_desc = strdup(FindKateCategoryName(p_stream->fmt.psz_description));
          if( psz_desc )
          {
              free( p_stream->fmt.psz_description );
              p_stream->fmt.psz_description = psz_desc;
          }
      }
      else
      {
          for( n = 0; n < 16; n++ )
              oggpack_read(&opb,8);
      }
  }
  
  static void Ogg_ReadAnnodexHeader( vlc_object_t *p_this,
                                     logical_stream_t *p_stream,
                                     ogg_packet *p_oggpacket )
  {
      if( p_oggpacket->bytes >= 28 &&
          !memcmp( p_oggpacket->packet, "Annodex", 7 ) )
      {
          oggpack_buffer opb;
  
          uint16_t major_version;
          uint16_t minor_version;
          uint64_t timebase_numerator;
          uint64_t timebase_denominator;
  
          Ogg_ReadTheoraHeader( p_stream, p_oggpacket );
  
          oggpack_readinit( &opb, p_oggpacket->packet, p_oggpacket->bytes);
          oggpack_adv( &opb, 8*8 ); /* "Annodex\0" header */
          major_version = oggpack_read( &opb, 2*8 ); /* major version */
          minor_version = oggpack_read( &opb, 2*8 ); /* minor version */
          timebase_numerator = GetQWLE( &p_oggpacket->packet[16] );
          timebase_denominator = GetQWLE( &p_oggpacket->packet[24] );
      }
      else if( p_oggpacket->bytes >= 42 &&
               !memcmp( p_oggpacket->packet, "AnxData", 7 ) )
      {
          uint64_t granule_rate_numerator;
          uint64_t granule_rate_denominator;
          char content_type_string[1024];
  
          /* Read in Annodex header fields */
  
          granule_rate_numerator = GetQWLE( &p_oggpacket->packet[8] );
          granule_rate_denominator = GetQWLE( &p_oggpacket->packet[16] );
          p_stream->i_secondary_header_packets =
              GetDWLE( &p_oggpacket->packet[24] );
  
          /* we are guaranteed that the first header field will be
           * the content-type (by the Annodex standard) */
          content_type_string[0] = '\0';
          if( !strncasecmp( (char*)(&p_oggpacket->packet[28]), "Content-Type: ", 14 ) )
          {
              uint8_t *p = memchr( &p_oggpacket->packet[42], '\r',
                                   p_oggpacket->bytes - 1 );
              if( p && p[0] == '\r' && p[1] == '\n' )
                  sscanf( (char*)(&p_oggpacket->packet[42]), "%1023s\r\n",
                          content_type_string );
          }
  
          msg_Dbg( p_this, "AnxData packet info: %"PRId64" / %"PRId64", %d, ``%s''",
                   granule_rate_numerator, granule_rate_denominator,
                   p_stream->i_secondary_header_packets, content_type_string );
  
          p_stream->f_rate = (float) granule_rate_numerator /
              (float) granule_rate_denominator;
  
          /* What type of file do we have?
           * strcmp is safe to use here because we've extracted
           * content_type_string from the stream manually */
          if( !strncmp(content_type_string, "audio/x-wav", 11) )
          {
              /* n.b. WAVs are unsupported right now */
              p_stream->fmt.i_cat = UNKNOWN_ES;
          }
          else if( !strncmp(content_type_string, "audio/x-vorbis", 14) )
          {
              p_stream->fmt.i_cat = AUDIO_ES;
              p_stream->fmt.i_codec = VLC_CODEC_VORBIS;
  
              p_stream->b_force_backup = 1;
          }
          else if( !strncmp(content_type_string, "audio/x-speex", 13) )
          {
              p_stream->fmt.i_cat = AUDIO_ES;
              p_stream->fmt.i_codec = VLC_CODEC_SPEEX;
  
              p_stream->b_force_backup = 1;
          }
          else if( !strncmp(content_type_string, "video/x-theora", 14) )
          {
              p_stream->fmt.i_cat = VIDEO_ES;
              p_stream->fmt.i_codec = VLC_CODEC_THEORA;
  
              p_stream->b_force_backup = 1;
          }
          else if( !strncmp(content_type_string, "video/x-xvid", 12) )
          {
              p_stream->fmt.i_cat = VIDEO_ES;
              p_stream->fmt.i_codec = VLC_FOURCC( 'x','v','i','d' );
  
              p_stream->b_force_backup = 1;
          }
          else if( !strncmp(content_type_string, "video/mpeg", 10) )
          {
              /* n.b. MPEG streams are unsupported right now */
              p_stream->fmt.i_cat = VIDEO_ES;
              p_stream->fmt.i_codec = VLC_CODEC_MPGV;
          }
          else if( !strncmp(content_type_string, "text/x-cmml", 11) )
          {
              ogg_stream_packetout( &p_stream->os, p_oggpacket );
              p_stream->fmt.i_cat = SPU_ES;
              p_stream->fmt.i_codec = VLC_CODEC_CMML;
          }
      }
  }
  
  static uint32_t dirac_uint( bs_t *p_bs )
  {
      uint32_t u_count = 0, u_value = 0;
  
      while( !bs_eof( p_bs ) && !bs_read( p_bs, 1 ) )
      {
          u_count++;
          u_value <<= 1;
          u_value |= bs_read( p_bs, 1 );
      }
  
      return (1<<u_count) - 1 + u_value;
  }
  
  static int dirac_bool( bs_t *p_bs )
  {
      return bs_read( p_bs, 1 );
  }
  
  static bool Ogg_ReadDiracHeader( logical_stream_t *p_stream,
                                   ogg_packet *p_oggpacket )
  {
      static const struct {
          uint32_t u_n /* numerator */, u_d /* denominator */;
      } p_dirac_frate_tbl[] = { /* table 10.3 */
          {1,1}, /* this first value is never used */
          {24000,1001}, {24,1}, {25,1}, {30000,1001}, {30,1},
          {50,1}, {60000,1001}, {60,1}, {15000,1001}, {25,2},
      };
      static const size_t u_dirac_frate_tbl = sizeof(p_dirac_frate_tbl)/sizeof(*p_dirac_frate_tbl);
  
      static const uint32_t pu_dirac_vidfmt_frate[] = { /* table C.1 */
          1, 9, 10, 9, 10, 9, 10, 4, 3, 7, 6, 4, 3, 7, 6, 2, 2, 7, 6, 7, 6,
      };
      static const size_t u_dirac_vidfmt_frate = sizeof(pu_dirac_vidfmt_frate)/sizeof(*pu_dirac_vidfmt_frate);
  
      bs_t bs;
  
      p_stream->i_granule_shift = 22; /* not 32 */
  
      /* Backing up stream headers is not required -- seqhdrs are repeated
       * thoughout the stream at suitable decoding start points */
      p_stream->b_force_backup = 0;
  
      /* read in useful bits from sequence header */
      bs_init( &bs, p_oggpacket->packet, p_oggpacket->bytes );
      bs_skip( &bs, 13*8); /* parse_info_header */
      dirac_uint( &bs ); /* major_version */
      dirac_uint( &bs ); /* minor_version */
      dirac_uint( &bs ); /* profile */
      dirac_uint( &bs ); /* level */
  
      uint32_t u_video_format = dirac_uint( &bs ); /* index */
      if( u_video_format >= u_dirac_vidfmt_frate )
      {
          /* don't know how to parse this ogg dirac stream */
          return false;
      }
  
      if( dirac_bool( &bs ) )
      {
          dirac_uint( &bs ); /* frame_width */
          dirac_uint( &bs ); /* frame_height */
      }
  
      if( dirac_bool( &bs ) )
      {
          dirac_uint( &bs ); /* chroma_format */
      }
  
      if( dirac_bool( &bs ) )
      {
          dirac_uint( &bs ); /* scan_format */
      }
  
      uint32_t u_n = p_dirac_frate_tbl[pu_dirac_vidfmt_frate[u_video_format]].u_n;
      uint32_t u_d = p_dirac_frate_tbl[pu_dirac_vidfmt_frate[u_video_format]].u_d;
      if( dirac_bool( &bs ) )
      {
          uint32_t u_frame_rate_index = dirac_uint( &bs );
          if( u_frame_rate_index >= u_dirac_frate_tbl )
          {
              /* something is wrong with this stream */
              return false;
          }
          u_n = p_dirac_frate_tbl[u_frame_rate_index].u_n;
          u_d = p_dirac_frate_tbl[u_frame_rate_index].u_d;
          if( u_frame_rate_index == 0 )
          {
              u_n = dirac_uint( &bs ); /* frame_rate_numerator */
              u_d = dirac_uint( &bs ); /* frame_rate_denominator */
          }
      }
      p_stream->f_rate = (float) u_n / u_d;
  
      /* probably is an ogg dirac es */
      p_stream->fmt.i_cat = VIDEO_ES;
      p_stream->fmt.i_codec = VLC_CODEC_DIRAC;
  
      return true;
  }
  