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