git.sesse.net Git - vlc/blob - modules/demux/nuv.c

   1 /*****************************************************************************
   2  * nuv.c:
   3  *****************************************************************************
   4  * Copyright (C) 2005 the VideoLAN team
   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
  10  * it under the terms of the GNU General Public License as published by
  11  * the Free Software Foundation; either version 2 of the License, or
  12  * (at your option) any later version.
  13  *
  14  * This program is distributed in the hope that it will be useful,
  15  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  17  * GNU General Public License for more details.
  18  *
  19  * You should have received a copy of the GNU General Public License
  20  * along with this program; if not, write to the Free Software
  21  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301, USA.
  22  *****************************************************************************/
  23
  24 /*****************************************************************************
  25  * Preamble
  26  *****************************************************************************/
  27 #ifdef HAVE_CONFIG_H
  28 # include "config.h"
  29 #endif
  30
  31 #include <vlc_common.h>
  32 #include <vlc_plugin.h>
  33 #include <vlc_demux.h>
  34
  35 /* TODO:
  36  *  - complete support (add support for rtjpeg and raw)
  37  *  - better seek support (to key frame)
  38  *  - control GET_LENGTH (harder, unless we have an extended header+index)
  39  *  - test
  40  */
  41
  42 /*****************************************************************************
  43  * Module descriptor
  44  *****************************************************************************/
  45 static int  Open  ( vlc_object_t * );
  46 static void Close ( vlc_object_t * );
  47
  48 vlc_module_begin();
  49     set_category( CAT_INPUT );
  50     set_subcategory( SUBCAT_INPUT_DEMUX );
  51     set_description( N_("Nuv demuxer") );
  52     set_capability( "demux", 145 );
  53     set_callbacks( Open, Close );
  54     add_shortcut( "nuv" );
  55 vlc_module_end();
  56
  57 /*****************************************************************************
  58  * Local prototypes
  59  *****************************************************************************/
  60 static int Demux  ( demux_t * );
  61 static int Control( demux_t *, int, va_list );
  62
  63 /* */
  64 typedef struct
  65 {
  66     int64_t i_time;
  67     int64_t i_offset;
  68
  69 } demux_index_entry_t;
  70
  71 typedef struct
  72 {
  73     int i_idx;
  74     int i_idx_max;
  75
  76     demux_index_entry_t *idx;
  77 } demux_index_t;
  78
  79
  80 static void demux_IndexInit( demux_index_t * );
  81 static void demux_IndexClean( demux_index_t * );
  82 static void demux_IndexAppend( demux_index_t *,
  83                                int64_t i_time, int64_t i_offset );
  84 /* Convert a time into offset */
  85 static int64_t demux_IndexConvertTime( demux_index_t *, int64_t i_time );
  86 /* Find the nearest offset in the index */
  87 static int64_t demux_IndexFindOffset( demux_index_t *, int64_t i_offset );
  88
  89
  90 /* */
  91 typedef struct
  92 {
  93     char id[12];       /* "NuppelVideo\0" or "MythTVVideo\0" */
  94     char version[5];    /* "x.xx\0" */
  95
  96     int  i_width;
  97     int  i_height;
  98     int  i_width_desired;
  99     int  i_height_desired;
 100
 101     char i_mode;            /* P progressive, I interlaced */
 102
 103     double  d_aspect;       /* 1.0 squared pixel */
 104     double  d_fps;
 105
 106     int     i_video_blocks; /* 0 no video, -1 unknown */
 107     int     i_audio_blocks;
 108     int     i_text_blocks;
 109
 110     int     i_keyframe_distance;
 111
 112 } header_t;
 113
 114 typedef struct
 115 {
 116     char i_type;        /* A: audio, V: video, S: sync; T: test
 117                            R: Seekpoint (string:RTjjjjjjjj)
 118                            D: Extra data for codec */
 119     char i_compression; /* V: 0 uncompressed
 120                               1 RTJpeg
 121                               2 RTJpeg+lzo
 122                               N black frame
 123                               L copy last
 124                            A: 0 uncompressed (44100 1-bits, 2ch)
 125                               1 lzo
 126                               2 layer 2
 127                               3 layer 3
 128                               F flac
 129                               S shorten
 130                               N null frame loudless
 131                               L copy last
 132                             S: B audio and vdeo sync point
 133                                A audio sync info (timecode == effective
 134                                     dsp frequency*100)
 135                                V next video sync (timecode == next video
 136                                     frame num)
 137                                S audio,video,text correlation */
 138     char i_keyframe;    /* 0 keyframe, else no no key frame */
 139     uint8_t i_filters;  /* 0x01: gauss 5 pixel (8,2,2,2,2)/16
 140                            0x02: gauss 5 pixel (8,1,1,1,1)/12
 141                            0x04: cartoon filter */
 142
 143     int i_timecode;     /* ms */
 144
 145     int i_length;       /* V,A,T: length of following data
 146                            S: length of packet correl */
 147 } frame_header_t;
 148
 149 /* FIXME Not sure of this one */
 150 typedef struct
 151 {
 152     int             i_version;
 153     vlc_fourcc_t    i_video_fcc;
 154
 155     vlc_fourcc_t    i_audio_fcc;
 156     int             i_audio_sample_rate;
 157     int             i_audio_bits_per_sample;
 158     int             i_audio_channels;
 159     int             i_audio_compression_ratio;
 160     int             i_audio_quality;
 161     int             i_rtjpeg_quality;
 162     int             i_rtjpeg_luma_filter;
 163     int             i_rtjpeg_chroma_filter;
 164     int             i_lavc_bitrate;
 165     int             i_lavc_qmin;
 166     int             i_lavc_qmax;
 167     int             i_lavc_maxqdiff;
 168     int64_t         i_seekable_offset;
 169     int64_t         i_keyframe_adjust_offset;
 170
 171 } extended_header_t;
 172
 173 struct demux_sys_t
 174 {
 175     header_t          hdr;
 176     extended_header_t exh;
 177
 178     int64_t     i_pcr;
 179     es_out_id_t *p_es_video;
 180     int         i_extra_f;
 181     uint8_t     *p_extra_f;
 182
 183     es_out_id_t *p_es_audio;
 184
 185     /* index */
 186     demux_index_t idx;
 187 };
 188
 189 static int HeaderLoad( demux_t *, header_t *h );
 190 static int FrameHeaderLoad( demux_t *, frame_header_t *h );
 191 static int ExtendedHeaderLoad( demux_t *, extended_header_t *h );
 192
 193 /*****************************************************************************
 194  * Open: initializes ES structures
 195  *****************************************************************************/
 196 static int Open( vlc_object_t * p_this )
 197 {
 198     demux_t     *p_demux = (demux_t*)p_this;
 199     demux_sys_t *p_sys;
 200     const uint8_t *p_peek;
 201     frame_header_t fh;
 202     bool  b_extended;
 203
 204     /* Check id */
 205     if( stream_Peek( p_demux->s, &p_peek, 12 ) != 12 ||
 206         ( strncmp( (char *)p_peek, "MythTVVideo", 11 ) &&
 207           strncmp( (char *)p_peek, "NuppelVideo", 11 ) ) )
 208         return VLC_EGENERIC;
 209
 210     p_sys = malloc( sizeof( demux_sys_t ) );
 211     memset( p_sys, 0, sizeof( demux_sys_t ) );
 212     p_sys->p_es_video = NULL;
 213     p_sys->p_es_audio = NULL;
 214     p_sys->p_extra_f = NULL;
 215     p_sys->i_pcr = -1;
 216     demux_IndexInit( &p_sys->idx );
 217
 218     if( HeaderLoad( p_demux, &p_sys->hdr ) )
 219         goto error;
 220
 221     /* Load 'D' */
 222     if( FrameHeaderLoad( p_demux, &fh ) || fh.i_type != 'D' )
 223         goto error;
 224     if( fh.i_length > 0 )
 225     {
 226         if( fh.i_compression == 'F' )
 227         {
 228             /* ffmpeg extra data */
 229             p_sys->i_extra_f = fh.i_length;
 230             p_sys->p_extra_f = malloc( fh.i_length );
 231             if( stream_Read( p_demux->s,
 232                              p_sys->p_extra_f, fh.i_length ) != fh.i_length )
 233                 goto error;
 234         }
 235         else
 236         {
 237             /* TODO handle rtjpeg */
 238             msg_Warn( p_demux, "unsupported 'D' frame (c=%c)", fh.i_compression );
 239             if( stream_Read( p_demux->s, NULL, fh.i_length ) != fh.i_length )
 240                 goto error;
 241         }
 242     }
 243
 244     /* Check and load extented */
 245     if( stream_Peek( p_demux->s, &p_peek, 1 ) != 1 )
 246         goto error;
 247     if( p_peek[0] == 'X' )
 248     {
 249         b_extended = true;
 250
 251         if( FrameHeaderLoad( p_demux, &fh ) )
 252             goto error;
 253         if( fh.i_length != 512 )
 254             goto error;
 255
 256         if( ExtendedHeaderLoad( p_demux, &p_sys->exh ) )
 257             goto error;
 258
 259     }
 260     else
 261     {
 262         b_extended = false;
 263
 264         /* XXX: for now only file with extended chunk are supported
 265          * why: because else we need to have support for rtjpeg+stupid nuv shit */
 266         msg_Err( p_demux, "incomplete NUV support (upload samples)" );
 267         goto error;
 268     }
 269
 270     /* Create audio/video (will work only with extended header and audio=mp3 */
 271     if( p_sys->hdr.i_video_blocks != 0 )
 272     {
 273         es_format_t fmt;
 274
 275         es_format_Init( &fmt, VIDEO_ES, p_sys->exh.i_video_fcc );
 276         fmt.video.i_width = p_sys->hdr.i_width;
 277         fmt.video.i_height = p_sys->hdr.i_height;
 278         fmt.i_extra = p_sys->i_extra_f;
 279         fmt.p_extra = p_sys->p_extra_f;
 280
 281         p_sys->p_es_video = es_out_Add( p_demux->out, &fmt );
 282     }
 283     if( p_sys->hdr.i_audio_blocks != 0 )
 284     {
 285         es_format_t fmt;
 286
 287         es_format_Init( &fmt, AUDIO_ES, VLC_FOURCC('m','p','g','a') );
 288         fmt.audio.i_rate = p_sys->exh.i_audio_sample_rate;
 289         fmt.audio.i_bitspersample = p_sys->exh.i_audio_bits_per_sample;
 290
 291         p_sys->p_es_audio = es_out_Add( p_demux->out, &fmt );
 292     }
 293     if( p_sys->hdr.i_text_blocks != 0 )
 294     {
 295         msg_Warn( p_demux, "text not yet supported (upload samples)" );
 296     }
 297
 298
 299     /* Fill p_demux fields */
 300     p_demux->pf_demux = Demux;
 301     p_demux->pf_control = Control;
 302     p_demux->p_sys = p_sys;
 303
 304     return VLC_SUCCESS;
 305
 306 error:
 307     msg_Warn( p_demux, "cannot load Nuv file" );
 308     free( p_sys );
 309     return VLC_EGENERIC;
 310 }
 311
 312 /*****************************************************************************
 313  * Close: frees unused data
 314  *****************************************************************************/
 315 static void Close( vlc_object_t * p_this )
 316 {
 317     demux_t        *p_demux = (demux_t*)p_this;
 318     demux_sys_t    *p_sys = p_demux->p_sys;
 319
 320     free( p_sys->p_extra_f );
 321     demux_IndexClean( &p_sys->idx );
 322     free( p_sys );
 323 }
 324
 325 /*****************************************************************************
 326  * Demux: reads and demuxes data packets
 327  *****************************************************************************
 328  * Returns -1 in case of error, 0 in case of EOF, 1 otherwise
 329  *****************************************************************************/
 330 static int Demux( demux_t *p_demux )
 331 {
 332     demux_sys_t *p_sys = p_demux->p_sys;
 333     frame_header_t fh;
 334     block_t *p_data;
 335
 336     for( ;; )
 337     {
 338         if( !vlc_object_alive (p_demux) )
 339             return -1;
 340
 341         if( FrameHeaderLoad( p_demux, &fh ) )
 342             return 0;
 343
 344         if( fh.i_type == 'A' || fh.i_type == 'V' )
 345             break;
 346
 347         /* TODO add support for some block type */
 348
 349         if( fh.i_type != 'R' )
 350         {
 351             stream_Read( p_demux->s, NULL, fh.i_length );
 352         }
 353     }
 354
 355     /* */
 356     p_data = stream_Block( p_demux->s, fh.i_length );
 357     p_data->i_dts = (int64_t)fh.i_timecode * 1000;
 358     p_data->i_pts = (fh.i_type == 'V') ? 0 : p_data->i_dts;
 359
 360     /* */
 361     demux_IndexAppend( &p_sys->idx, p_data->i_dts, stream_Tell(p_demux->s) );
 362
 363     /* */
 364     if( p_data->i_dts > p_sys->i_pcr )
 365     {
 366         p_sys->i_pcr = p_data->i_dts;
 367         es_out_Control( p_demux->out, ES_OUT_SET_PCR, p_sys->i_pcr );
 368     }
 369
 370     if( fh.i_type == 'A' && p_sys->p_es_audio )
 371     {
 372         if( fh.i_compression == '3' )
 373             es_out_Send( p_demux->out, p_sys->p_es_audio, p_data );
 374         else
 375         {
 376             msg_Dbg( p_demux, "unsupported compression %c for audio (upload samples)", fh.i_compression );
 377             block_Release( p_data );
 378         }
 379     }
 380     else if( fh.i_type == 'V' && p_sys->p_es_video )
 381     {
 382         if( fh.i_compression >= '4' )
 383             es_out_Send( p_demux->out, p_sys->p_es_video, p_data );
 384         else
 385         {
 386             msg_Dbg( p_demux, "unsupported compression %c for video (upload samples)", fh.i_compression );
 387             block_Release( p_data );
 388         }
 389     }
 390     else
 391     {
 392         block_Release( p_data );
 393     }
 394
 395     return 1;
 396 }
 397
 398 /*****************************************************************************
 399  * Control:
 400  *****************************************************************************/
 401 static int Control( demux_t *p_demux, int i_query, va_list args )
 402 {
 403     demux_sys_t *p_sys  = p_demux->p_sys;
 404
 405     double   f, *pf;
 406     int64_t i64, *pi64;
 407
 408     switch( i_query )
 409     {
 410
 411         case DEMUX_GET_POSITION:
 412             pf = (double*)va_arg( args, double * );
 413             i64 = stream_Size( p_demux->s );
 414             if( i64 > 0 )
 415                 *pf = (double)stream_Tell( p_demux->s ) / (double)i64;
 416             else
 417                 *pf = 0.0;
 418             return VLC_SUCCESS;
 419
 420         case DEMUX_SET_POSITION:
 421         {
 422             int64_t i_pos;
 423
 424             f = (double)va_arg( args, double );
 425             i_pos = stream_Size( p_demux->s ) * f;
 426
 427             i64 = demux_IndexFindOffset( &p_sys->idx, i_pos );
 428
 429             p_sys->i_pcr = -1;
 430
 431             if( i64 >= 0 )
 432                 return stream_Seek( p_demux->s, i64 );
 433
 434             if( p_sys->idx.i_idx > 0 )
 435             {
 436                 if( stream_Seek( p_demux->s, p_sys->idx.idx[p_sys->idx.i_idx-1].i_offset ) )
 437                     return VLC_EGENERIC;
 438             }
 439             else
 440             {
 441                 if( stream_Seek( p_demux->s, 0 ) )
 442                     return VLC_EGENERIC;
 443             }
 444
 445             while( vlc_object_alive (p_demux) )
 446             {
 447                 frame_header_t fh;
 448                 int64_t i_tell;
 449
 450                 if( ( i_tell = stream_Tell( p_demux->s ) ) >= i_pos )
 451                     break;
 452
 453                 if( FrameHeaderLoad( p_demux, &fh ) )
 454                     return VLC_EGENERIC;
 455
 456                 if( fh.i_type == 'A' || fh.i_type == 'V' )
 457                     demux_IndexAppend( &p_sys->idx,(int64_t)fh.i_timecode*1000, i_tell );
 458
 459                 if( fh.i_type != 'R' )
 460                     stream_Read( p_demux->s, NULL, fh.i_length );
 461             }
 462             return VLC_SUCCESS;
 463         }
 464
 465
 466         case DEMUX_GET_TIME:
 467             pi64 = (int64_t*)va_arg( args, int64_t * );
 468             *pi64 = p_sys->i_pcr >= 0 ? p_sys->i_pcr : 0;
 469             return VLC_SUCCESS;
 470
 471         case DEMUX_SET_TIME:
 472         {
 473             int64_t i_pos;
 474             i64 = (int64_t)va_arg( args, int64_t );
 475
 476             i_pos = demux_IndexConvertTime( &p_sys->idx, i64 );
 477             if( i_pos < 0 )
 478                 return VLC_EGENERIC;
 479
 480             if( stream_Seek( p_demux->s, i_pos ) )
 481                 return VLC_EGENERIC;
 482
 483             p_sys->i_pcr = -1;
 484
 485             while( vlc_object_alive (p_demux) )
 486             {
 487                 frame_header_t fh;
 488
 489                 if( FrameHeaderLoad( p_demux, &fh ) )
 490                     return VLC_EGENERIC;
 491
 492                 if( fh.i_type == 'A' || fh.i_type == 'V' )
 493                 {
 494                     int64_t i_time = (int64_t)fh.i_timecode*1000;
 495                     int64_t i_tell = stream_Tell(p_demux->s)-12;
 496
 497                     demux_IndexAppend( &p_sys->idx, i_time, i_tell );
 498
 499                     if( i_time >= i64 )
 500                         return stream_Seek( p_demux->s, i_tell );
 501                 }
 502                 if( fh.i_type != 'R' )
 503                     stream_Read( p_demux->s, NULL, fh.i_length );
 504             }
 505             return VLC_SUCCESS;
 506         }
 507
 508         case DEMUX_GET_LENGTH:
 509             pi64 = (int64_t*)va_arg( args, int64_t * );
 510             return VLC_EGENERIC;
 511
 512         case DEMUX_GET_FPS:
 513             pf = (double*)va_arg( args, double * );
 514             *pf = p_sys->hdr.d_fps;
 515             return VLC_SUCCESS;
 516
 517         case DEMUX_GET_META:
 518         default:
 519             return VLC_EGENERIC;
 520
 521     }
 522 }
 523
 524 /*****************************************************************************
 525  *
 526  *****************************************************************************/
 527 static inline void GetDoubleLE( double *pd, void *src )
 528 {
 529     /* FIXME works only if sizeof(double) == 8 */
 530 #ifdef WORDS_BIGENDIAN
 531     uint8_t *p = (uint8_t*)pd, *q = (uint8_t*)src;
 532     int i;
 533     for( i = 0; i < 8; i++ )
 534         p[i] = q[7-i];
 535 #else
 536     memcpy( pd, src, 8 );
 537 #endif
 538 }
 539
 540 /* HeaderLoad:
 541  */
 542 static int HeaderLoad( demux_t *p_demux, header_t *h )
 543 {
 544     uint8_t buffer[72];
 545
 546     if( stream_Read( p_demux->s, buffer, 72 ) != 72 )
 547         return VLC_EGENERIC;
 548
 549     /* XXX: they are alignment to take care of (another broken format) */
 550     memcpy( h->id,      &buffer[ 0], 12 );
 551     memcpy( h->version, &buffer[12], 5 );
 552     h->i_width = GetDWLE( &buffer[20] );
 553     h->i_height = GetDWLE( &buffer[24] );
 554     h->i_width_desired = GetDWLE( &buffer[28] );
 555     h->i_height_desired = GetDWLE( &buffer[32] );
 556     h->i_mode = buffer[36];
 557     GetDoubleLE( &h->d_aspect, &buffer[40] );
 558     GetDoubleLE( &h->d_fps, &buffer[48] );
 559     h->i_video_blocks = GetDWLE( &buffer[56] );
 560     h->i_audio_blocks = GetDWLE( &buffer[60] );
 561     h->i_text_blocks = GetDWLE( &buffer[64] );
 562     h->i_keyframe_distance = GetDWLE( &buffer[68] );
 563 #if 0
 564     msg_Dbg( p_demux, "nuv: h=%s v=%s %dx%d a=%f fps=%f v=%d a=%d t=%d kfd=%d",
 565              h->id, h->version, h->i_width, h->i_height, h->d_aspect,
 566              h->d_fps, h->i_video_blocks, h->i_audio_blocks, h->i_text_blocks,
 567              h->i_keyframe_distance );
 568 #endif
 569     return VLC_SUCCESS;
 570 }
 571
 572 /* FrameHeaderLoad:
 573  */
 574 static int FrameHeaderLoad( demux_t *p_demux, frame_header_t *h )
 575 {
 576     uint8_t buffer[12];
 577
 578     if( stream_Read( p_demux->s, buffer, 12 ) != 12 )
 579         return VLC_EGENERIC;
 580
 581     h->i_type = buffer[0];
 582     h->i_compression = buffer[1];
 583     h->i_keyframe = buffer[2];
 584     h->i_filters = buffer[3];
 585
 586     h->i_timecode = GetDWLE( &buffer[4] );
 587     h->i_length = GetDWLE( &buffer[8] );
 588 #if 0
 589     msg_Dbg( p_demux, "frame hdr: t=%c c=%c k=%d f=0x%x timecode=%d l=%d",
 590              h->i_type,
 591              h->i_compression ? h->i_compression : ' ',
 592              h->i_keyframe ? h->i_keyframe : ' ',
 593              h->i_filters,
 594              h->i_timecode, h->i_length );
 595 #endif
 596     return VLC_SUCCESS;
 597 }
 598
 599 static int ExtendedHeaderLoad( demux_t *p_demux, extended_header_t *h )
 600 {
 601     uint8_t buffer[512];
 602
 603     if( stream_Read( p_demux->s, buffer, 512 ) != 512 )
 604         return VLC_EGENERIC;
 605
 606     h->i_version = GetDWLE( &buffer[0] );
 607     h->i_video_fcc = VLC_FOURCC( buffer[4], buffer[5], buffer[6], buffer[7] );
 608     h->i_audio_fcc = VLC_FOURCC( buffer[8], buffer[9], buffer[10], buffer[11] );
 609     h->i_audio_sample_rate = GetDWLE( &buffer[12] );
 610     h->i_audio_bits_per_sample = GetDWLE( &buffer[16] );
 611     h->i_audio_channels = GetDWLE( &buffer[20] );
 612     h->i_audio_compression_ratio = GetDWLE( &buffer[24] );
 613     h->i_audio_quality = GetDWLE( &buffer[28] );
 614     h->i_rtjpeg_quality = GetDWLE( &buffer[32] );
 615     h->i_rtjpeg_luma_filter = GetDWLE( &buffer[36] );
 616     h->i_rtjpeg_chroma_filter = GetDWLE( &buffer[40] );
 617     h->i_lavc_bitrate = GetDWLE( &buffer[44] );
 618     h->i_lavc_qmin = GetDWLE( &buffer[48] );
 619     h->i_lavc_qmin = GetDWLE( &buffer[52] );
 620     h->i_lavc_maxqdiff = GetDWLE( &buffer[56] );
 621     h->i_seekable_offset = GetQWLE( &buffer[60] );
 622     h->i_keyframe_adjust_offset= GetQWLE( &buffer[68] );
 623 #if 0
 624     msg_Dbg( p_demux, "ex hdr: v=%d vffc=%4.4s afcc=%4.4s %dHz %dbits ach=%d acr=%d aq=%d"
 625                       "rtjpeg q=%d lf=%d lc=%d lavc br=%d qmin=%d qmax=%d maxqdiff=%d seekableoff=%lld keyfao=%lld",
 626              h->i_version,
 627              (char*)&h->i_video_fcc,
 628              (char*)&h->i_audio_fcc, h->i_audio_sample_rate, h->i_audio_bits_per_sample, h->i_audio_channels,
 629              h->i_audio_compression_ratio, h->i_audio_quality,
 630              h->i_rtjpeg_quality, h->i_rtjpeg_luma_filter, h->i_rtjpeg_chroma_filter,
 631              h->i_lavc_bitrate, h->i_lavc_qmin, h->i_lavc_qmax, h->i_lavc_maxqdiff,
 632              h->i_seekable_offset, h->i_keyframe_adjust_offset );
 633 #endif
 634     return VLC_SUCCESS;
 635 }
 636
 637 /*****************************************************************************/
 638 #define DEMUX_INDEX_SIZE_MAX (100000)
 639 static void demux_IndexInit( demux_index_t *p_idx )
 640 {
 641     p_idx->i_idx = 0;
 642     p_idx->i_idx_max = 0;
 643     p_idx->idx = NULL;
 644 }
 645 static void demux_IndexClean( demux_index_t *p_idx )
 646 {
 647     free( p_idx->idx );
 648     p_idx->idx = NULL;
 649 }
 650 static void demux_IndexAppend( demux_index_t *p_idx,
 651                                int64_t i_time, int64_t i_offset )
 652 {
 653     /* Be sure to append new entry (we don't insert point) */
 654     if( p_idx->i_idx > 0 && p_idx->idx[p_idx->i_idx-1].i_time >= i_time )
 655         return;
 656
 657     /* */
 658     if( p_idx->i_idx >= p_idx->i_idx_max )
 659     {
 660         if( p_idx->i_idx >= DEMUX_INDEX_SIZE_MAX )
 661         {
 662             /* Avoid too big index */
 663             const int64_t i_length = p_idx->idx[p_idx->i_idx-1].i_time -
 664                                                         p_idx->idx[0].i_time;
 665             const int i_count = DEMUX_INDEX_SIZE_MAX/2;
 666             int i, j;
 667
 668             /* We try to reduce the resolution of the index by a factor 2 */
 669             for( i = 1, j = 1; i < p_idx->i_idx; i++ )
 670             {
 671                 if( p_idx->idx[i].i_time < j * i_length / i_count )
 672                     continue;
 673
 674                 p_idx->idx[j++] = p_idx->idx[i];
 675             }
 676             p_idx->i_idx = j;
 677
 678             if( p_idx->i_idx > 3 * DEMUX_INDEX_SIZE_MAX / 4 )
 679             {
 680                 /* We haven't created enough space
 681                  * (This method won't create a good index but work for sure) */
 682                 for( i = 0; i < p_idx->i_idx/2; i++ )
 683                     p_idx->idx[i] = p_idx->idx[2*i];
 684                 p_idx->i_idx /= 2;
 685             }
 686         }
 687         else
 688         {
 689             p_idx->i_idx_max += 1000;
 690             p_idx->idx = realloc( p_idx->idx,
 691                                   p_idx->i_idx_max*sizeof(demux_index_entry_t));
 692         }
 693     }
 694
 695     /* */
 696     p_idx->idx[p_idx->i_idx].i_time = i_time;
 697     p_idx->idx[p_idx->i_idx].i_offset = i_offset;
 698
 699     p_idx->i_idx++;
 700 }
 701 static int64_t demux_IndexConvertTime( demux_index_t *p_idx, int64_t i_time )
 702 {
 703     int i_min = 0;
 704     int i_max = p_idx->i_idx-1;
 705
 706     /* Empty index */
 707     if( p_idx->i_idx <= 0 )
 708         return -1;
 709
 710     /* Special border case */
 711     if( i_time <= p_idx->idx[0].i_time )
 712         return p_idx->idx[0].i_offset;
 713     if( i_time >= p_idx->idx[i_max].i_time )
 714         return p_idx->idx[i_max].i_offset;
 715
 716     /* Dicho */
 717     for( ;; )
 718     {
 719         int i_med;
 720
 721         if( i_max - i_min <= 1 )
 722             break;
 723
 724         i_med = (i_min+i_max)/2;
 725         if( p_idx->idx[i_med].i_time < i_time )
 726             i_min = i_med;
 727         else if( p_idx->idx[i_med].i_time > i_time )
 728             i_max = i_med;
 729         else
 730             return p_idx->idx[i_med].i_offset;
 731     }
 732
 733     /* return nearest in time */
 734     if( i_time - p_idx->idx[i_min].i_time < p_idx->idx[i_max].i_time - i_time )
 735         return p_idx->idx[i_min].i_offset;
 736     else
 737         return p_idx->idx[i_max].i_offset;
 738 }
 739
 740
 741 static int64_t demux_IndexFindOffset( demux_index_t *p_idx, int64_t i_offset )
 742 {
 743     int i_min = 0;
 744     int i_max = p_idx->i_idx-1;
 745
 746     /* Empty index */
 747     if( p_idx->i_idx <= 0 )
 748         return -1;
 749
 750     /* Special border case */
 751     if( i_offset <= p_idx->idx[0].i_offset )
 752         return p_idx->idx[0].i_offset;
 753     if( i_offset == p_idx->idx[i_max].i_offset )
 754         return p_idx->idx[i_max].i_offset;
 755     if( i_offset > p_idx->idx[i_max].i_offset )
 756         return -1;
 757
 758     /* Dicho */
 759     for( ;; )
 760     {
 761         int i_med;
 762
 763         if( i_max - i_min <= 1 )
 764             break;
 765
 766         i_med = (i_min+i_max)/2;
 767         if( p_idx->idx[i_med].i_offset < i_offset )
 768             i_min = i_med;
 769         else if( p_idx->idx[i_med].i_offset > i_offset )
 770             i_max = i_med;
 771         else
 772             return p_idx->idx[i_med].i_offset;
 773     }
 774
 775     /* return nearest */
 776     if( i_offset - p_idx->idx[i_min].i_offset < p_idx->idx[i_max].i_offset - i_offset )
 777         return p_idx->idx[i_min].i_offset;
 778     else
 779         return p_idx->idx[i_max].i_offset;
 780 }