include/vlc_demux.h

   1 /*****************************************************************************
   2  * vlc_demux.h: Demuxer descriptor, queries and methods
   3  *****************************************************************************
   4  * Copyright (C) 1999-2005 VLC authors and VideoLAN
   5  * $Id$
   6  *
   7  * Authors: Laurent Aimar <fenrir@via.ecp.fr>
   8  *
   9  * This program is free software; you can redistribute it and/or modify it
  10  * under the terms of the GNU Lesser General Public License as published by
  11  * the Free Software Foundation; either version 2.1 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 Lesser General Public License for more details.
  18  *
  19  * You should have received a copy of the GNU Lesser General Public License
  20  * along with this program; if not, write to the Free Software Foundation,
  21  * Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301, USA.
  22  *****************************************************************************/
  23
  24 #ifndef VLC_DEMUX_H
  25 #define VLC_DEMUX_H 1
  26
  27 /**
  28  * \file
  29  * This files defines functions and structures used by demux objects in vlc
  30  */
  31
  32 #include <vlc_es.h>
  33 #include <vlc_stream.h>
  34 #include <vlc_es_out.h>
  35
  36 /**
  37  * \defgroup demux Demux
  38  * @{
  39  */
  40
  41 struct demux_t
  42 {
  43     VLC_COMMON_MEMBERS
  44
  45     /* Module properties */
  46     module_t    *p_module;
  47
  48     /* eg informative but needed (we can have access+demux) */
  49     char        *psz_access;
  50     char        *psz_demux;
  51     char        *psz_location;
  52     char        *psz_file;
  53
  54     /* input stream */
  55     stream_t    *s;     /* NULL in case of a access+demux in one */
  56
  57     /* es output */
  58     es_out_t    *out;   /* our p_es_out */
  59
  60     /* set by demuxer */
  61     int (*pf_demux)  ( demux_t * );   /* demux one frame only */
  62     int (*pf_control)( demux_t *, int i_query, va_list args);
  63
  64     /* Demux has to maintain them uptodate
  65      * when it is responsible of seekpoint/title */
  66     struct
  67     {
  68         unsigned int i_update;  /* Demux sets them on change,
  69                                    Input removes them once take into account*/
  70         /* Seekpoint/Title at demux level */
  71         int          i_title;       /* idem, start from 0 (could be menu) */
  72         int          i_seekpoint;   /* idem, start from 0 */
  73     } info;
  74     demux_sys_t *p_sys;
  75
  76     /* Weak link to parent input */
  77     input_thread_t *p_input;
  78 };
  79
  80 /* demux_t.info.i_update field */
  81 #define INPUT_UPDATE_TITLE      0x0010
  82 #define INPUT_UPDATE_SEEKPOINT  0x0020
  83 #define INPUT_UPDATE_META       0x0040
  84 #define INPUT_UPDATE_TITLE_LIST 0x0100
  85
  86 /* demux_meta_t is returned by "meta reader" module to the demuxer */
  87 typedef struct demux_meta_t
  88 {
  89     VLC_COMMON_MEMBERS
  90     demux_t *p_demux; /** FIXME: use stream_t instead? */
  91     input_item_t *p_item; /***< the input item that is being read */
  92
  93     vlc_meta_t *p_meta;                 /**< meta data */
  94
  95     int i_attachments;                  /**< number of attachments */
  96     input_attachment_t **attachments;    /**< array of attachments */
  97 } demux_meta_t;
  98
  99 enum demux_query_e
 100 {
 101     /* I. Common queries to access_demux and demux */
 102     /* POSITION double between 0.0 and 1.0 */
 103     DEMUX_GET_POSITION,         /* arg1= double *       res=    */
 104     DEMUX_SET_POSITION,         /* arg1= double arg2= bool b_precise    res=can fail    */
 105
 106     /* LENGTH/TIME in microsecond, 0 if unknown */
 107     DEMUX_GET_LENGTH,           /* arg1= int64_t *      res=    */
 108     DEMUX_GET_TIME,             /* arg1= int64_t *      res=    */
 109     DEMUX_SET_TIME,             /* arg1= int64_t arg2= bool b_precise   res=can fail    */
 110
 111     /* TITLE_INFO only if more than 1 title or 1 chapter */
 112     DEMUX_GET_TITLE_INFO,       /* arg1=input_title_t*** arg2=int*
 113                                    arg3=int*pi_title_offset(0), arg4=int*pi_seekpoint_offset(0) can fail */
 114     /* TITLE/SEEKPOINT, only when TITLE_INFO succeed */
 115     DEMUX_SET_TITLE,            /* arg1= int            can fail */
 116     DEMUX_SET_SEEKPOINT,        /* arg1= int            can fail */
 117
 118     /* DEMUX_SET_GROUP/SET_ES only a hint for demuxer (mainly DVB) to allow not
 119      * reading everything (you should not use this to call es_out_Control)
 120      * if you don't know what to do with it, just IGNORE it, it is safe(r)
 121      * -1 means all group, 0 default group (first es added) */
 122     DEMUX_SET_GROUP,            /* arg1= int, arg2=const vlc_list_t *   can fail */
 123     DEMUX_SET_ES,               /* arg1= int                            can fail */
 124
 125     /* Ask the demux to demux until the given date at the next pf_demux call
 126      * but not more (and not less, at the precision available of course).
 127      * XXX: not mandatory (except for subtitle demux) but will help a lot
 128      * for multi-input
 129      */
 130     DEMUX_SET_NEXT_DEMUX_TIME,  /* arg1= int64_t        can fail */
 131     /* FPS for correct subtitles handling */
 132     DEMUX_GET_FPS,              /* arg1= double *       res=can fail    */
 133
 134     /* Meta data */
 135     DEMUX_GET_META,             /* arg1= vlc_meta_t **  res=can fail    */
 136     DEMUX_HAS_UNSUPPORTED_META, /* arg1= bool *   res can fail    */
 137
 138     /* Attachments */
 139     DEMUX_GET_ATTACHMENTS,      /* arg1=input_attachment_t***, int* res=can fail */
 140
 141     /* RECORD you are ensured that it is never called twice with the same state
 142      * you should accept it only if the stream can be recorded without
 143      * any modification or header addition. */
 144     DEMUX_CAN_RECORD,           /* arg1=bool*   res=can fail(assume false) */
 145     DEMUX_SET_RECORD_STATE,     /* arg1=bool    res=can fail */
 146
 147     DEMUX_GET_SIGNAL, /* arg1=double *pf_quality, arg2=double *pf_strength
 148                          res=can fail */
 149
 150     /* II. Specific access_demux queries */
 151     /* PAUSE you are ensured that it is never called twice with the same state */
 152     DEMUX_CAN_PAUSE = 0x1000,   /* arg1= bool*    can fail (assume false)*/
 153     DEMUX_SET_PAUSE_STATE,      /* arg1= bool     can fail */
 154
 155     DEMUX_GET_PTS_DELAY,        /* arg1= int64_t*       cannot fail */
 156
 157     /* DEMUX_CAN_CONTROL_PACE returns true (*pb_pace) if we can read the
 158      * data at our pace */
 159     DEMUX_CAN_CONTROL_PACE,     /* arg1= bool*pb_pace    can fail (assume false) */
 160
 161     /* DEMUX_CAN_CONTROL_RATE is called only if DEMUX_CAN_CONTROL_PACE has returned false.
 162      * *pb_rate should be true when the rate can be changed (using DEMUX_SET_RATE)
 163      * *pb_ts_rescale should be true when the timestamps (pts/dts/pcr) have to be rescaled */
 164     DEMUX_CAN_CONTROL_RATE,     /* arg1= bool*pb_rate arg2= bool*pb_ts_rescale  can fail(assume false) */
 165     /* DEMUX_SET_RATE is called only if DEMUX_CAN_CONTROL_RATE has returned true.
 166      * It should return the value really used in *pi_rate */
 167     DEMUX_SET_RATE,             /* arg1= int*pi_rate                                        can fail */
 168
 169     DEMUX_CAN_SEEK,            /* arg1= bool*    can fail (assume false)*/
 170
 171     /* Navigation */
 172     DEMUX_NAV_ACTIVATE,        /* res=can fail */
 173     DEMUX_NAV_UP,              /* res=can fail */
 174     DEMUX_NAV_DOWN,            /* res=can fail */
 175     DEMUX_NAV_LEFT,            /* res=can fail */
 176     DEMUX_NAV_RIGHT,           /* res=can fail */
 177 };
 178
 179 VLC_API int demux_vaControlHelper( stream_t *, int64_t i_start, int64_t i_end, int64_t i_bitrate, int i_align, int i_query, va_list args );
 180
 181 static inline void demux_UpdateTitleFromStream( demux_t *demux )
 182 {
 183     stream_t *s = demux->s;
 184     unsigned title, seekpoint;
 185
 186     if( stream_Control( s, STREAM_GET_TITLE, &title ) == VLC_SUCCESS
 187      && title != (unsigned)demux->info.i_title )
 188     {
 189         demux->info.i_title = title;
 190         demux->info.i_update |= INPUT_UPDATE_TITLE;
 191     }
 192
 193     if( stream_Control( s, STREAM_GET_SEEKPOINT, &seekpoint ) == VLC_SUCCESS
 194      && seekpoint != (unsigned)demux->info.i_seekpoint )
 195     {
 196         demux->info.i_seekpoint = seekpoint;
 197         demux->info.i_update |= INPUT_UPDATE_SEEKPOINT;
 198     }
 199 }
 200
 201 /*************************************************************************
 202  * Miscellaneous helpers for demuxers
 203  *************************************************************************/
 204
 205 VLC_USED
 206 static inline bool demux_IsPathExtension( demux_t *p_demux, const char *psz_extension )
 207 {
 208     const char *name = (p_demux->psz_file != NULL) ? p_demux->psz_file
 209                                                    : p_demux->psz_location;
 210     const char *psz_ext = strrchr ( name, '.' );
 211     if( !psz_ext || strcasecmp( psz_ext, psz_extension ) )
 212         return false;
 213     return true;
 214 }
 215
 216 VLC_USED
 217 static inline bool demux_IsForced( demux_t *p_demux, const char *psz_name )
 218 {
 219    if( !p_demux->psz_demux || strcmp( p_demux->psz_demux, psz_name ) )
 220         return false;
 221     return true;
 222 }
 223
 224 /**
 225  * This function will create a packetizer suitable for a demuxer that parses
 226  * elementary stream.
 227  *
 228  * The provided es_format_t will be cleaned on error or by
 229  * demux_PacketizerDestroy.
 230  */
 231 VLC_API decoder_t * demux_PacketizerNew( demux_t *p_demux, es_format_t *p_fmt, const char *psz_msg ) VLC_USED;
 232
 233 /**
 234  * This function will destroy a packetizer create by demux_PacketizerNew.
 235  */
 236 VLC_API void demux_PacketizerDestroy( decoder_t *p_packetizer );
 237
 238 /**
 239  * This function will return the parent input of this demux.
 240  * It is retained. Can return NULL.
 241  */
 242 VLC_API input_thread_t * demux_GetParentInput( demux_t *p_demux ) VLC_USED;
 243
 244 /* */
 245 #define DEMUX_INIT_COMMON() do {            \
 246     p_demux->pf_control = Control;          \
 247     p_demux->pf_demux = Demux;              \
 248     p_demux->p_sys = calloc( 1, sizeof( demux_sys_t ) ); \
 249     if( !p_demux->p_sys ) return VLC_ENOMEM;\
 250     } while(0)
 251
 252 /**
 253  * @}
 254  */
 255
 256 #endif