modules/demux/mjpeg.c

   1 /*****************************************************************************
   2  * mjpeg.c : demuxes mjpeg webcam http streams
   3  *****************************************************************************
   4  * Copyright (C) 2004 VLC authors and VideoLAN
   5  *
   6  * Authors: Henry Jen (slowhog) <henryjen@ztune.net>
   7  *          Derk-Jan Hartman (thedj)
   8  *          Sigmund Augdal (Dnumgis)
   9  *          Laurent Aimar <fenrir@via.ecp.fr>
  10  *
  11  * This program is free software; you can redistribute it and/or modify it
  12  * under the terms of the GNU Lesser General Public License as published by
  13  * the Free Software Foundation; either version 2.1 of the License, or
  14  * (at your option) any later version.
  15  *
  16  * This program is distributed in the hope that it will be useful,
  17  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  18  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  19  * GNU Lesser General Public License for more details.
  20  *
  21  * You should have received a copy of the GNU Lesser General Public License
  22  * along with this program; if not, write to the Free Software Foundation,
  23  * Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301, USA.
  24  *****************************************************************************/
  25
  26 /*****************************************************************************
  27  * Preamble
  28  *****************************************************************************/
  29
  30 #ifdef HAVE_CONFIG_H
  31 # include "config.h"
  32 #endif
  33
  34 #include <vlc_common.h>
  35 #include <vlc_plugin.h>
  36 #include <vlc_demux.h>
  37 #include "mxpeg_helper.h"
  38
  39 /*****************************************************************************
  40  * Module descriptor
  41  *****************************************************************************/
  42 static int  Open ( vlc_object_t * );
  43
  44 #define FPS_TEXT N_("Frames per Second")
  45 #define FPS_LONGTEXT N_("This is the desired frame rate when " \
  46     "playing MJPEG from a file. Use 0 (this is the default value) for a " \
  47     "live stream (from a camera).")
  48
  49 vlc_module_begin ()
  50     set_shortname( "MJPEG")
  51     set_description( N_("M-JPEG camera demuxer") )
  52     set_capability( "demux", 5 )
  53     set_callback( Open )
  54     set_category( CAT_INPUT )
  55     set_subcategory( SUBCAT_INPUT_DEMUX )
  56     add_float( "mjpeg-fps", 0.0, FPS_TEXT, FPS_LONGTEXT, false )
  57 vlc_module_end ()
  58
  59 /*****************************************************************************
  60  * Local prototypes
  61  *****************************************************************************/
  62 static int MimeDemux( demux_t * );
  63 static int MjpgDemux( demux_t * );
  64 static int Control( demux_t *, int i_query, va_list args );
  65
  66 typedef struct
  67 {
  68     es_format_t     fmt;
  69     es_out_id_t     *p_es;
  70
  71     bool            b_still;
  72     vlc_tick_t      i_still_end;
  73     vlc_tick_t      i_time;
  74     vlc_tick_t      i_frame_length;
  75     char            *psz_separator;
  76     int             i_frame_size_estimate;
  77     const uint8_t   *p_peek;
  78     int             i_data_peeked;
  79     int             i_level;
  80 } demux_sys_t;
  81
  82 /*****************************************************************************
  83  * Peek: Helper function to peek data with incremental size.
  84  * \return false if peek no more data, true otherwise.
  85  *****************************************************************************/
  86 static bool Peek( demux_t *p_demux, bool b_first )
  87 {
  88     int i_data;
  89     demux_sys_t *p_sys = p_demux->p_sys;
  90
  91     if( b_first )
  92     {
  93         p_sys->i_data_peeked = 0;
  94     }
  95     else if( p_sys->i_data_peeked == p_sys->i_frame_size_estimate )
  96     {
  97         p_sys->i_frame_size_estimate += 5120;
  98     }
  99     i_data = vlc_stream_Peek( p_demux->s, &p_sys->p_peek,
 100                           p_sys->i_frame_size_estimate );
 101     if( i_data == p_sys->i_data_peeked )
 102     {
 103         msg_Warn( p_demux, "no more data" );
 104         return false;
 105     }
 106     p_sys->i_data_peeked = i_data;
 107     if( i_data <= 0 )
 108     {
 109         msg_Warn( p_demux, "cannot peek data" );
 110         return false;
 111     }
 112     return true;
 113 }
 114
 115 /*****************************************************************************
 116  * GetLine: Internal function used to dup a line of string from the buffer
 117  *****************************************************************************/
 118 static char* GetLine( demux_t *p_demux, int *p_pos )
 119 {
 120     demux_sys_t *p_sys = p_demux->p_sys;
 121     const uint8_t *p_buf;
 122     int         i_size;
 123     int         i;
 124     char        *p_line;
 125
 126     while( *p_pos >= p_sys->i_data_peeked )
 127     {
 128         if( ! Peek( p_demux, false ) )
 129         {
 130             return NULL;
 131         }
 132     }
 133     p_buf = p_sys->p_peek + *p_pos;
 134     i_size = p_sys->i_data_peeked - *p_pos;
 135     i = 0;
 136     while( p_buf[i] != '\n' )
 137     {
 138         i++;
 139         if( i == i_size )
 140         {
 141             if( ! Peek( p_demux, false ) )
 142             {
 143                 return NULL;
 144             }
 145             p_buf = p_sys->p_peek + *p_pos;
 146             i_size = p_sys->i_data_peeked - *p_pos;
 147         }
 148     }
 149     *p_pos += i + 1;
 150     if( i > 0 && p_buf[i - 1] == '\r' )
 151     {
 152         i--;
 153     }
 154     p_line = malloc( i + 1 );
 155     if( unlikely( p_line == NULL ) )
 156         return NULL;
 157     strncpy ( p_line, (char*)p_buf, i );
 158     p_line[i] = '\0';
 159     return p_line;
 160 }
 161
 162 /*****************************************************************************
 163  * CheckMimeHeader: Internal function used to verify and skip mime header
 164  * \param p_header_size Return size of MIME header, 0 if no MIME header
 165  * detected, minus value if error
 166  * \return true if content type is image/jpeg, false otherwise
 167  *****************************************************************************/
 168 static bool CheckMimeHeader( demux_t *p_demux, int *p_header_size )
 169 {
 170     bool        b_jpeg = false;
 171     int         i_pos = 0;
 172     char        *psz_line;
 173     char        *p_ch;
 174     demux_sys_t *p_sys = p_demux->p_sys;
 175
 176     *p_header_size = -1;
 177     if( !Peek( p_demux, true ) )
 178     {
 179         msg_Err( p_demux, "cannot peek" );
 180         return false;
 181     }
 182     if( p_sys->i_data_peeked < 5)
 183     {
 184         msg_Err( p_demux, "data shortage" );
 185         return false;
 186     }
 187     if( strncmp( (char *)p_sys->p_peek, "--", 2 ) != 0
 188         && strncmp( (char *)p_sys->p_peek, "\r\n--", 4 ) != 0 )
 189     {
 190         *p_header_size = 0;
 191         return false;
 192     }
 193     else
 194     {
 195         i_pos = *p_sys->p_peek == '-' ? 2 : 4;
 196         psz_line = GetLine( p_demux, &i_pos );
 197         if( NULL == psz_line )
 198         {
 199             msg_Err( p_demux, "no EOL" );
 200             return false;
 201         }
 202
 203         /* Read the separator and remember it if not yet stored */
 204         if( p_sys->psz_separator == NULL )
 205         {
 206             p_sys->psz_separator = psz_line;
 207             msg_Dbg( p_demux, "Multipart MIME detected, using separator: %s",
 208                      p_sys->psz_separator );
 209         }
 210         else
 211         {
 212             if( strcmp( psz_line, p_sys->psz_separator ) )
 213             {
 214                 msg_Warn( p_demux, "separator %s does not match %s", psz_line,
 215                           p_sys->psz_separator );
 216             }
 217             free( psz_line );
 218         }
 219     }
 220
 221     psz_line = GetLine( p_demux, &i_pos );
 222     while( psz_line && *psz_line )
 223     {
 224         if( !strncasecmp( psz_line, "Content-Type:", 13 ) )
 225         {
 226             p_ch = psz_line + 13;
 227             while( *p_ch != '\0' && ( *p_ch == ' ' || *p_ch == '\t' ) ) p_ch++;
 228             if( strncasecmp( p_ch, "image/jpeg", 10 ) )
 229             {
 230                 msg_Warn( p_demux, "%s, image/jpeg is expected", psz_line );
 231                 b_jpeg = false;
 232             }
 233             else
 234             {
 235                 b_jpeg = true;
 236             }
 237         }
 238         else
 239         {
 240             msg_Dbg( p_demux, "discard MIME header: %s", psz_line );
 241         }
 242         free( psz_line );
 243         psz_line = GetLine( p_demux, &i_pos );
 244     }
 245
 246     if( NULL == psz_line )
 247     {
 248         msg_Err( p_demux, "no EOL" );
 249         return false;
 250     }
 251
 252     free( psz_line );
 253
 254     *p_header_size = i_pos;
 255     return b_jpeg;
 256 }
 257
 258 static int SendBlock( demux_t *p_demux, int i )
 259 {
 260     demux_sys_t *p_sys = p_demux->p_sys;
 261     block_t     *p_block;
 262
 263     if( ( p_block = vlc_stream_Block( p_demux->s, i ) ) == NULL )
 264     {
 265         msg_Warn( p_demux, "cannot read data" );
 266         return VLC_DEMUXER_EOF;
 267     }
 268
 269     if( p_sys->i_frame_length != VLC_TICK_INVALID )
 270     {
 271         p_block->i_pts = p_sys->i_time;
 272         p_sys->i_time += p_sys->i_frame_length;
 273     }
 274     else
 275     {
 276         p_block->i_pts = vlc_tick_now();
 277     }
 278     p_block->i_dts = p_block->i_pts;
 279
 280     es_out_SetPCR( p_demux->out, p_block->i_pts );
 281     es_out_Send( p_demux->out, p_sys->p_es, p_block );
 282
 283     if( p_sys->b_still )
 284         p_sys->i_still_end = vlc_tick_now() + p_sys->i_frame_length;
 285
 286     return VLC_DEMUXER_SUCCESS;
 287 }
 288
 289 /*****************************************************************************
 290  * Open: check file and initializes structures
 291  *****************************************************************************/
 292 static int Open( vlc_object_t * p_this )
 293 {
 294     demux_t     *p_demux = (demux_t*)p_this;
 295     int         i_size;
 296     bool        b_matched = false;
 297
 298     if( IsMxpeg( p_demux->s ) && !p_demux->obj.force )
 299         // let avformat handle this case
 300         return VLC_EGENERIC;
 301
 302     demux_sys_t *p_sys = vlc_obj_malloc( p_this, sizeof (*p_sys) );
 303     if( unlikely(p_sys == NULL) )
 304         return VLC_ENOMEM;
 305
 306     p_demux->p_sys      = p_sys;
 307     p_sys->p_es         = NULL;
 308     p_sys->i_time       = VLC_TICK_0;
 309     p_sys->i_level      = 0;
 310
 311     p_sys->psz_separator = NULL;
 312     p_sys->i_frame_size_estimate = 15 * 1024;
 313
 314     char *content_type = stream_ContentType( p_demux->s );
 315     if ( content_type )
 316     {
 317         //FIXME: this is not fully match to RFC
 318         char* boundary = strstr( content_type, "boundary=" );
 319         if( boundary )
 320         {
 321             boundary += strlen( "boundary=" );
 322             size_t len = strlen( boundary );
 323             if( len > 2 && boundary[0] == '"'
 324                 && boundary[len-1] == '"' )
 325             {
 326                 boundary[len-1] = '\0';
 327                 boundary++;
 328             }
 329             p_sys->psz_separator = vlc_obj_strdup( p_this, boundary );
 330             if( !p_sys->psz_separator )
 331             {
 332                 free( content_type );
 333                 return VLC_ENOMEM;
 334             }
 335         }
 336         free( content_type );
 337     }
 338
 339     b_matched = CheckMimeHeader( p_demux, &i_size);
 340     if( b_matched )
 341     {
 342         p_demux->pf_demux = MimeDemux;
 343         if( vlc_stream_Read( p_demux->s, NULL, i_size ) < i_size )
 344             return VLC_EGENERIC;
 345     }
 346     else if( i_size == 0 )
 347     {
 348         /* 0xffd8 identify a JPEG SOI */
 349         if( p_sys->p_peek[0] == 0xFF && p_sys->p_peek[1] == 0xD8 )
 350         {
 351             msg_Dbg( p_demux, "JPEG SOI marker detected" );
 352             p_demux->pf_demux = MjpgDemux;
 353             p_sys->i_level++;
 354         }
 355         else
 356         {
 357             return VLC_EGENERIC;
 358         }
 359     }
 360     else
 361     {
 362         return VLC_EGENERIC;
 363     }
 364
 365     /* Frame rate */
 366     float f_fps = var_InheritFloat( p_demux, "mjpeg-fps" );
 367
 368     p_sys->i_still_end = VLC_TICK_INVALID;
 369     if( demux_IsPathExtension( p_demux, ".jpeg" ) ||
 370         demux_IsPathExtension( p_demux, ".jpg" ) )
 371     {
 372         /* Plain JPEG file = single still picture */
 373         p_sys->b_still = true;
 374         if( f_fps == 0.f )
 375             /* Defaults to 1fps */
 376             f_fps = 1.f;
 377     }
 378     else
 379         p_sys->b_still = false;
 380     p_sys->i_frame_length = f_fps ? vlc_tick_rate_duration(f_fps) : VLC_TICK_INVALID;
 381
 382     es_format_Init( &p_sys->fmt, VIDEO_ES, VLC_CODEC_MJPG );
 383
 384     p_sys->fmt.i_id = 0;
 385     p_sys->p_es = es_out_Add( p_demux->out, &p_sys->fmt );
 386     if( unlikely(p_sys->p_es == NULL) )
 387         return VLC_ENOMEM;
 388
 389     p_demux->pf_control = Control;
 390     return VLC_SUCCESS;
 391 }
 392
 393 /*****************************************************************************
 394  * Demux: read packet and send them to decoders
 395  *****************************************************************************
 396  * Returns -1 in case of error, 0 in case of EOF, 1 otherwise
 397  *****************************************************************************/
 398 static int MjpgDemux( demux_t *p_demux )
 399 {
 400     demux_sys_t *p_sys = p_demux->p_sys;
 401     int i;
 402
 403     if( p_sys->b_still && p_sys->i_still_end != VLC_TICK_INVALID )
 404     {
 405         /* Still frame, wait until the pause delay is gone */
 406         vlc_tick_wait( p_sys->i_still_end );
 407         p_sys->i_still_end = VLC_TICK_INVALID;
 408         return VLC_DEMUXER_SUCCESS;
 409     }
 410
 411     if( !Peek( p_demux, true ) )
 412     {
 413         msg_Warn( p_demux, "cannot peek data" );
 414         return VLC_DEMUXER_EOF;
 415     }
 416     if( p_sys->i_data_peeked < 4 )
 417     {
 418         msg_Warn( p_demux, "data shortage" );
 419         return VLC_DEMUXER_EOF;
 420     }
 421     i = 3;
 422 FIND_NEXT_EOI:
 423     while( !( p_sys->p_peek[i-1] == 0xFF && p_sys->p_peek[i] == 0xD9 ) )
 424     {
 425         if( p_sys->p_peek[i-1] == 0xFF && p_sys->p_peek[i] == 0xD9  )
 426         {
 427             p_sys->i_level++;
 428             msg_Dbg( p_demux, "we found another JPEG SOI at %d", i );
 429         }
 430         i++;
 431         if( i >= p_sys->i_data_peeked )
 432         {
 433             msg_Dbg( p_demux, "did not find JPEG EOI in %d bytes",
 434                      p_sys->i_data_peeked );
 435             if( !Peek( p_demux, false ) )
 436             {
 437                 msg_Warn( p_demux, "no more data is available at the moment" );
 438                 return VLC_DEMUXER_EOF;
 439             }
 440         }
 441     }
 442     i++;
 443
 444     msg_Dbg( p_demux, "JPEG EOI detected at %d", i );
 445     p_sys->i_level--;
 446
 447     if( p_sys->i_level > 0 )
 448         goto FIND_NEXT_EOI;
 449     return SendBlock( p_demux, i );
 450 }
 451
 452 static int MimeDemux( demux_t *p_demux )
 453 {
 454     demux_sys_t *p_sys = p_demux->p_sys;
 455     int         i_size, i;
 456
 457     bool  b_match = CheckMimeHeader( p_demux, &i_size );
 458
 459     if( i_size > 0 )
 460     {
 461         if( vlc_stream_Read( p_demux->s, NULL, i_size ) != i_size )
 462             return VLC_DEMUXER_EOF;
 463     }
 464     else if( i_size < 0 )
 465     {
 466         return VLC_DEMUXER_EOF;
 467     }
 468     else
 469     {
 470         // No MIME header, assume OK
 471         b_match = true;
 472     }
 473
 474     if( !Peek( p_demux, true ) )
 475     {
 476         msg_Warn( p_demux, "cannot peek data" );
 477         return VLC_DEMUXER_EOF;
 478     }
 479
 480     i = 0;
 481     i_size = strlen( p_sys->psz_separator ) + 2;
 482     if( p_sys->i_data_peeked < i_size )
 483     {
 484         msg_Warn( p_demux, "data shortage" );
 485         return VLC_DEMUXER_EOF;
 486     }
 487
 488     for( ;; )
 489     {
 490         while( !( p_sys->p_peek[i] == '-' && p_sys->p_peek[i+1] == '-' ) )
 491         {
 492             i++;
 493             i_size++;
 494             if( i_size >= p_sys->i_data_peeked )
 495             {
 496                 msg_Dbg( p_demux, "MIME boundary not found in %d bytes of "
 497                          "data", p_sys->i_data_peeked );
 498
 499                 if( !Peek( p_demux, false ) )
 500                 {
 501                     msg_Warn( p_demux, "no more data is available at the "
 502                               "moment" );
 503                     return VLC_DEMUXER_EOF;
 504                 }
 505             }
 506         }
 507
 508         /* Handle old and new style of separators */
 509         if (!strncmp(p_sys->psz_separator, (char *)(p_sys->p_peek + i + 2),
 510                      strlen( p_sys->psz_separator ))
 511          || ((strlen(p_sys->psz_separator) > 4)
 512           && !strncmp(p_sys->psz_separator, "--", 2)
 513           && !strncmp(p_sys->psz_separator, (char *)(p_sys->p_peek + i),
 514                       strlen( p_sys->psz_separator))))
 515         {
 516             break;
 517         }
 518
 519         i++;
 520         i_size++;
 521     }
 522
 523     if( !b_match )
 524     {
 525         msg_Err( p_demux, "discard non-JPEG part" );
 526         return VLC_DEMUXER_EOF;
 527     }
 528
 529     return SendBlock( p_demux, i );
 530 }
 531
 532 /*****************************************************************************
 533  * Control:
 534  *****************************************************************************/
 535 static int Control( demux_t *p_demux, int i_query, va_list args )
 536 {
 537     return demux_vaControlHelper( p_demux->s, 0, 0, 0, 0, i_query, args );
 538 }