modules/demux/flac.c

   1 /*****************************************************************************
   2  * flac.c : FLAC demux module for vlc
   3  *****************************************************************************
   4  * Copyright (C) 2001-2003 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 #include <vlc/vlc.h>
  28 #include <vlc_demux.h>
  29 #include <vlc_meta.h>
  30 #include <vlc_codec.h>
  31
  32 /*****************************************************************************
  33  * Module descriptor
  34  *****************************************************************************/
  35 static int  Open  ( vlc_object_t * );
  36 static void Close ( vlc_object_t * );
  37
  38 vlc_module_begin();
  39     set_description( _("FLAC demuxer") );
  40     set_capability( "demux2", 155 );
  41     set_category( CAT_INPUT );
  42     set_subcategory( SUBCAT_INPUT_DEMUX );
  43     set_callbacks( Open, Close );
  44     add_shortcut( "flac" );
  45 vlc_module_end();
  46
  47 /*****************************************************************************
  48  * Local prototypes
  49  *****************************************************************************/
  50 static int Demux  ( demux_t * );
  51 static int Control( demux_t *, int, va_list );
  52
  53 struct demux_sys_t
  54 {
  55     vlc_bool_t  b_start;
  56     es_out_id_t *p_es;
  57
  58     /* Packetizer */
  59     decoder_t *p_packetizer;
  60     vlc_meta_t *p_meta;
  61 };
  62
  63 #define STREAMINFO_SIZE 38
  64 #define FLAC_PACKET_SIZE 16384
  65
  66 /*****************************************************************************
  67  * Open: initializes ES structures
  68  *****************************************************************************/
  69 static int Open( vlc_object_t * p_this )
  70 {
  71     demux_t     *p_demux = (demux_t*)p_this;
  72     module_t    *p_id3;
  73     demux_sys_t *p_sys;
  74     int          i_peek;
  75     byte_t      *p_peek;
  76     es_format_t  fmt;
  77
  78     /* Have a peep at the show. */
  79     if( stream_Peek( p_demux->s, &p_peek, 4 ) < 4 ) return VLC_EGENERIC;
  80
  81     if( p_peek[0]!='f' || p_peek[1]!='L' || p_peek[2]!='a' || p_peek[3]!='C' )
  82     {
  83         if( !p_demux->b_force ) return VLC_EGENERIC;
  84
  85         /* User forced */
  86         msg_Err( p_demux, "this doesn't look like a flac stream, "
  87                  "continuing anyway" );
  88     }
  89
  90     p_demux->pf_demux   = Demux;
  91     p_demux->pf_control = Control;
  92     p_demux->p_sys      = p_sys = malloc( sizeof( demux_sys_t ) );
  93     es_format_Init( &fmt, AUDIO_ES, VLC_FOURCC( 'f', 'l', 'a', 'c' ) );
  94     p_sys->b_start = VLC_TRUE;
  95     p_sys->p_meta = NULL;
  96
  97     /* We need to read and store the STREAMINFO metadata */
  98     i_peek = stream_Peek( p_demux->s, &p_peek, 8 );
  99     if( p_peek[4] & 0x7F )
 100     {
 101         msg_Err( p_demux, "this isn't a STREAMINFO metadata block" );
 102         return VLC_EGENERIC;
 103     }
 104
 105     if( ((p_peek[5]<<16)+(p_peek[6]<<8)+p_peek[7]) != (STREAMINFO_SIZE - 4) )
 106     {
 107         msg_Err( p_demux, "invalid size for a STREAMINFO metadata block" );
 108         return VLC_EGENERIC;
 109     }
 110
 111     /* Load the FLAC packetizer */
 112     INIT_APACKETIZER( p_sys->p_packetizer, 'f', 'l', 'a', 'c' );
 113
 114     /* Store STREAMINFO for the decoder and packetizer */
 115     p_sys->p_packetizer->fmt_in.i_extra = fmt.i_extra = STREAMINFO_SIZE + 4;
 116     p_sys->p_packetizer->fmt_in.p_extra = malloc( STREAMINFO_SIZE + 4 );
 117     stream_Read( p_demux->s, p_sys->p_packetizer->fmt_in.p_extra,
 118                  STREAMINFO_SIZE + 4 );
 119
 120     /* Fake this as the last metadata block */
 121     ((uint8_t*)p_sys->p_packetizer->fmt_in.p_extra)[4] |= 0x80;
 122     fmt.p_extra = malloc( STREAMINFO_SIZE + 4 );
 123     memcpy( fmt.p_extra, p_sys->p_packetizer->fmt_in.p_extra,
 124             STREAMINFO_SIZE + 4 );
 125
 126     p_sys->p_packetizer->p_module =
 127         module_Need( p_sys->p_packetizer, "packetizer", NULL, 0 );
 128     if( !p_sys->p_packetizer->p_module )
 129     {
 130         if( p_sys->p_packetizer->fmt_in.p_extra )
 131             free( p_sys->p_packetizer->fmt_in.p_extra );
 132         vlc_object_destroy( p_sys->p_packetizer );
 133
 134         msg_Err( p_demux, "cannot find flac packetizer" );
 135         return VLC_EGENERIC;
 136     }
 137
 138     p_sys->p_es = es_out_Add( p_demux->out, &fmt );
 139
 140     /* Parse possible id3 header */
 141     if( ( p_id3 = module_Need( p_demux, "meta reader", NULL, 0 ) ) )
 142     {
 143         p_sys->p_meta = (vlc_meta_t *)p_demux->p_private;
 144         p_demux->p_private = NULL;
 145         module_Unneed( p_demux, p_id3 );
 146     }
 147
 148     return VLC_SUCCESS;
 149 }
 150
 151 /*****************************************************************************
 152  * Close: frees unused data
 153  *****************************************************************************/
 154 static void Close( vlc_object_t * p_this )
 155 {
 156     demux_t     *p_demux = (demux_t*)p_this;
 157     demux_sys_t *p_sys = p_demux->p_sys;
 158
 159     /* Unneed module */
 160     module_Unneed( p_sys->p_packetizer, p_sys->p_packetizer->p_module );
 161
 162     if( p_sys->p_packetizer->fmt_in.p_extra )
 163         free( p_sys->p_packetizer->fmt_in.p_extra );
 164
 165     /* Delete the decoder */
 166     vlc_object_destroy( p_sys->p_packetizer );
 167     if( p_sys->p_meta ) vlc_meta_Delete( p_sys->p_meta );
 168     free( p_sys );
 169 }
 170
 171 /*****************************************************************************
 172  * Demux: reads and demuxes data packets
 173  *****************************************************************************
 174  * Returns -1 in case of error, 0 in case of EOF, 1 otherwise
 175  *****************************************************************************/
 176 static int Demux( demux_t *p_demux )
 177 {
 178     demux_sys_t *p_sys = p_demux->p_sys;
 179     block_t     *p_block_in, *p_block_out;
 180
 181     if( !( p_block_in = stream_Block( p_demux->s, FLAC_PACKET_SIZE ) ) )
 182     {
 183         return 0;
 184     }
 185
 186     if( p_sys->b_start )
 187     {
 188         p_block_in->i_pts = p_block_in->i_dts = 1;
 189         p_sys->b_start = VLC_FALSE;
 190     }
 191     else
 192     {
 193         p_block_in->i_pts = p_block_in->i_dts = 0;
 194     }
 195
 196     while( (p_block_out = p_sys->p_packetizer->pf_packetize(
 197                 p_sys->p_packetizer, &p_block_in )) )
 198     {
 199         while( p_block_out )
 200         {
 201             block_t *p_next = p_block_out->p_next;
 202
 203             /* set PCR */
 204             es_out_Control( p_demux->out, ES_OUT_SET_PCR, p_block_out->i_dts );
 205
 206             es_out_Send( p_demux->out, p_sys->p_es, p_block_out );
 207
 208             p_block_out = p_next;
 209         }
 210     }
 211
 212     return 1;
 213 }
 214
 215 /*****************************************************************************
 216  * Control:
 217  *****************************************************************************/
 218 static int Control( demux_t *p_demux, int i_query, va_list args )
 219 {
 220     /* demux_sys_t *p_sys  = p_demux->p_sys; */
 221     /* FIXME bitrate */
 222     if( i_query == DEMUX_SET_TIME ) return VLC_EGENERIC;
 223     else if( i_query == DEMUX_GET_META )
 224     {
 225         vlc_meta_t *p_meta = (vlc_meta_t *)va_arg( args, vlc_meta_t* );
 226         if( p_demux->p_sys->p_meta )
 227             vlc_meta_Merge( p_meta, p_demux->p_sys->p_meta );
 228         return VLC_SUCCESS;
 229     }
 230     else return demux2_vaControlHelper( p_demux->s, 0, -1,
 231                                         8*0, 1, i_query, args );
 232 }
 233