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

   1 /*****************************************************************************
   2  * nuv.c:
   3  *****************************************************************************
   4  * Copyright (C) 2005 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
  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., 59 Temple Place - Suite 330, Boston, MA  02111, USA.
  22  *****************************************************************************/
  23
  24 /*****************************************************************************
  25  * Preamble
  26  *****************************************************************************/
  27 #include <vlc/vlc.h>
  28 #include <vlc/input.h>
  29
  30 /* TODO:
  31  *  - complete support (add support for rtjpeg and raw)
  32  *  - better seek support (to key frame)
  33  *  - control GET_LENGTH (harder, unless we have an extended header+index)
  34  *  - test
  35  */
  36
  37 /*****************************************************************************
  38  * Module descriptor
  39  *****************************************************************************/
  40 static int  Open  ( vlc_object_t * );
  41 static void Close ( vlc_object_t * );
  42
  43 vlc_module_begin();
  44     set_category( CAT_INPUT );
  45     set_subcategory( SUBCAT_INPUT_DEMUX );
  46     set_description( _("Nuv demuxer") );
  47     set_capability( "demux2", 145 );
  48     set_callbacks( Open, Close );
  49     add_shortcut( "nuv" );
  50 vlc_module_end();
  51
  52 /*****************************************************************************
  53  * Local prototypes
  54  *****************************************************************************/
  55 static int Demux  ( demux_t * );
  56 static int Control( demux_t *, int, va_list );
  57
  58 /* */
  59 typedef struct
  60 {
  61     int64_t i_time;
  62     int64_t i_offset;
  63
  64 } demux_index_entry_t;
  65
  66 typedef struct
  67 {
  68     int i_idx;
  69     int i_idx_max;
  70
  71     demux_index_entry_t *idx;
  72 } demux_index_t;
  73
  74
  75 static void demux_IndexInit( demux_index_t * );
  76 static void demux_IndexClean( demux_index_t * );
  77 static void demux_IndexAppend( demux_index_t *,
  78                                int64_t i_time, int64_t i_offset );
  79 /* Convert a time into offset */
  80 static int64_t demux_IndexConvertTime( demux_index_t *, int64_t i_time );
  81 /* Find the nearest offset in the index */
  82 static int64_t demux_IndexFindOffset( demux_index_t *, int64_t i_offset );
  83
  84
  85 /* */
  86 typedef struct
  87 {
  88     char id[12];       /* "NuppelVideo\0" or "MythTVVideo\0" */
  89     char version[5];    /* "x.xx\0" */
  90
  91     int  i_width;
  92     int  i_height;
  93     int  i_width_desired;
  94     int  i_height_desired;
  95
  96     char i_mode;            /* P progressive, I interlaced */
  97
  98     double  d_aspect;       /* 1.0 squared pixel */
  99     double  d_fps;
 100
 101     int     i_video_blocks; /* 0 no video, -1 unknown */
 102     int     i_audio_blocks;
 103     int     i_text_blocks;
 104
 105     int     i_keyframe_distance;
 106
 107 } header_t;
 108
 109 typedef struct
 110 {
 111     char i_type;        /* A: audio, V: video, S: sync; T: test
 112                            R: Seekpoint (string:RTjjjjjjjj)
 113                            D: Extra data for codec */
 114     char i_compression; /* V: 0 uncompressed
 115                               1 RTJpeg
 116                               2 RTJpeg+lzo
 117                               N black frame
 118                               L copy last
 119                            A: 0 uncompressed (44100 1-bits, 2ch)
 120                               1 lzo
 121                               2 layer 2
 122                               3 layer 3
 123                               F flac
 124                               S shorten
 125                               N null frame loudless
 126                               L copy last
 127                             S: B audio and vdeo sync point
 128                                A audio sync info (timecode == effective
 129                                     dsp frequency*100)
 130                                V next video sync (timecode == next video
 131                                     frame num)
 132                                S audio,video,text correlation */
 133     char i_keyframe;    /* 0 keyframe, else no no key frame */
 134     uint8_t i_filters;  /* 0x01: gauss 5 pixel (8,2,2,2,2)/16
 135                            0x02: gauss 5 pixel (8,1,1,1,1)/12
 136                            0x04: cartoon filter */
 137
 138     int i_timecode;     /* ms */
 139
 140     int i_length;       /* V,A,T: length of following data
 141                            S: length of packet correl */
 142 } frame_header_t;
 143
 144 /* FIXME Not sure of this one */
 145 typedef struct
 146 {
 147     int             i_version;
 148     vlc_fourcc_t    i_video_fcc;
 149
 150     vlc_fourcc_t    i_audio_fcc;
 151     int             i_audio_sample_rate;
 152     int             i_audio_bits_per_sample;
 153     int             i_audio_channels;
 154     int             i_audio_compression_ratio;
 155     int             i_audio_quality;
 156     int             i_rtjpeg_quality;
 157     int             i_rtjpeg_luma_filter;
 158     int             i_rtjpeg_chroma_filter;
 159     int             i_lavc_bitrate;
 160     int             i_lavc_qmin;
 161     int             i_lavc_qmax;
 162     int             i_lavc_maxqdiff;
 163     int64_t         i_seekable_offset;
 164     int64_t         i_keyframe_adjust_offset;
 165
 166 } extended_header_t;
 167
 168 struct demux_sys_t
 169 {
 170     header_t          hdr;
 171     extended_header_t exh;
 172
 173     int64_t     i_pcr;
 174     es_out_id_t *p_es_video;
 175     int         i_extra_f;
 176     uint8_t     *p_extra_f;
 177
 178     es_out_id_t *p_es_audio;
 179
 180     /* index */
 181     demux_index_t idx;
 182 };
 183
 184 static int HeaderLoad( demux_t *, header_t *h );
 185 static int FrameHeaderLoad( demux_t *, frame_header_t *h );
 186 static int ExtendedHeaderLoad( demux_t *, extended_header_t *h );
 187
 188 /*****************************************************************************
 189  * Open: initializes ES structures
 190  *****************************************************************************/
 191 static int Open( vlc_object_t * p_this )
 192 {
 193     demux_t     *p_demux = (demux_t*)p_this;
 194     demux_sys_t *p_sys;
 195     uint8_t     *p_peek;
 196     frame_header_t fh;
 197     vlc_bool_t  b_extended;
 198
 199     /* Check id */
 200     if( stream_Peek( p_demux->s, &p_peek, 12 ) != 12 ||
 201         ( strncmp( p_peek, "MythTVVideo", 11 ) &&
 202           strncmp( p_peek, "NuppelVideo", 11 ) ) )
 203         return VLC_EGENERIC;
 204
 205     p_sys = malloc( sizeof( demux_sys_t ) );
 206     memset( p_sys, 0, sizeof( demux_sys_t ) );
 207     p_sys->p_es_video = NULL;
 208     p_sys->p_es_audio = NULL;
 209     p_sys->p_extra_f = NULL;
 210     p_sys->i_pcr = -1;
 211     demux_IndexInit( &p_sys->idx );
 212
 213     if( HeaderLoad( p_demux, &p_sys->hdr ) )
 214         goto error;
 215
 216     /* Load 'D' */
 217     if( FrameHeaderLoad( p_demux, &fh ) || fh.i_type != 'D' )
 218         goto error;
 219     if( fh.i_length > 0 )
 220     {
 221         if( fh.i_compression == 'F' )
 222         {
 223             /* ffmpeg extra data */
 224             p_sys->i_extra_f = fh.i_length;
 225             p_sys->p_extra_f = malloc( fh.i_length );
 226             if( stream_Read( p_demux->s,
 227                              p_sys->p_extra_f, fh.i_length ) != fh.i_length )
 228                 goto error;
 229         }
 230         else
 231         {
 232             /* TODO handle rtjpeg */
 233             msg_Warn( p_demux, "unsuported 'D' frame (c=%c)", fh.i_compression );
 234             if( stream_Read( p_demux->s, NULL, fh.i_length ) != fh.i_length )
 235                 goto error;
 236         }
 237     }
 238
 239     /* Check and load extented */
 240     if( stream_Peek( p_demux->s, &p_peek, 1 ) != 1 )
 241         goto error;
 242     if( p_peek[0] == 'X' )
 243     {
 244         b_extended = VLC_TRUE;
 245
 246         if( FrameHeaderLoad( p_demux, &fh ) )
 247             goto error;
 248         if( fh.i_length != 512 )
 249             goto error;
 250
 251         if( ExtendedHeaderLoad( p_demux, &p_sys->exh ) )
 252             goto error;
 253
 254     }
 255     else
 256     {
 257         b_extended = VLC_FALSE;
 258
 259         /* XXX: for now only file with extended chunk are supported
 260          * why: because else we need to have support for rtjpeg+stupid nuv shit */
 261         msg_Err( p_demux, "incomplete NUV support (upload samples)" );
 262         goto error;
 263     }
 264
 265     /* Create audio/video (will work only with extended header and audio=mp3 */
 266     if( p_sys->hdr.i_video_blocks != 0 )
 267     {
 268         es_format_t fmt;
 269
 270         es_format_Init( &fmt, VIDEO_ES, p_sys->exh.i_video_fcc );
 271         fmt.video.i_width = p_sys->hdr.i_width;
 272         fmt.video.i_height = p_sys->hdr.i_height;
 273         fmt.i_extra = p_sys->i_extra_f;
 274         fmt.p_extra = p_sys->p_extra_f;
 275
 276         p_sys->p_es_video = es_out_Add( p_demux->out, &fmt );
 277     }
 278     if( p_sys->hdr.i_audio_blocks != 0 )
 279     {
 280         es_format_t fmt;
 281
 282         es_format_Init( &fmt, AUDIO_ES, VLC_FOURCC('m','p','g','a') );
 283         fmt.audio.i_rate = p_sys->exh.i_audio_sample_rate;
 284         fmt.audio.i_bitspersample = p_sys->exh.i_audio_bits_per_sample;
 285
 286         p_sys->p_es_audio = es_out_Add( p_demux->out, &fmt );
 287     }
 288     if( p_sys->hdr.i_text_blocks != 0 )
 289     {
 290         msg_Warn( p_demux, "text not yet supported (upload samples)" );
 291     }
 292
 293
 294     /* Fill p_demux fields */
 295     p_demux->pf_demux = Demux;
 296     p_demux->pf_control = Control;
 297     p_demux->p_sys = p_sys;
 298
 299     return VLC_SUCCESS;
 300
 301 error:
 302     msg_Warn( p_demux, "cannot load Nuv file" );
 303     free( p_sys );
 304     return VLC_EGENERIC;
 305 }
 306
 307 /*****************************************************************************
 308  * Close: frees unused data
 309  *****************************************************************************/
 310 static void Close( vlc_object_t * p_this )
 311 {
 312     demux_t        *p_demux = (demux_t*)p_this;
 313     demux_sys_t    *p_sys = p_demux->p_sys;
 314
 315     if( p_sys->p_extra_f )
 316         free( p_sys->p_extra_f );
 317     demux_IndexClean( &p_sys->idx );
 318     free( p_sys );
 319 }
 320
 321 /*****************************************************************************
 322  * Demux: reads and demuxes data packets
 323  *****************************************************************************
 324  * Returns -1 in case of error, 0 in case of EOF, 1 otherwise
 325  *****************************************************************************/
 326 static int Demux( demux_t *p_demux )
 327 {
 328     demux_sys_t *p_sys = p_demux->p_sys;
 329     frame_header_t fh;
 330     block_t *p_data;
 331
 332     for( ;; )
 333     {
 334         if( p_demux->b_die )
 335             return -1;
 336
 337         if( FrameHeaderLoad( p_demux, &fh ) )
 338             return 0;
 339
 340         if( fh.i_type == 'A' || fh.i_type == 'V' )
 341             break;
 342
 343         /* TODO add support for some block type */
 344
 345         if( fh.i_type != 'R' )
 346         {
 347             stream_Read( p_demux->s, NULL, fh.i_length );
 348         }
 349     }
 350
 351     /* */
 352     p_data = stream_Block( p_demux->s, fh.i_length );
 353     p_data->i_dts = (int64_t)fh.i_timecode * 1000;
 354     p_data->i_pts = (fh.i_type == 'V') ? 0 : p_data->i_dts;
 355
 356     /* */
 357     demux_IndexAppend( &p_sys->idx, p_data->i_dts, stream_Tell(p_demux->s) );
 358
 359     /* */
 360     if( p_data->i_dts > p_sys->i_pcr )
 361     {
 362         p_sys->i_pcr = p_data->i_dts;
 363         es_out_Control( p_demux->out, ES_OUT_SET_PCR, p_sys->i_pcr );
 364     }
 365
 366     if( fh.i_type == 'A' && p_sys->p_es_audio )
 367     {
 368         if( fh.i_compression == '3' )
 369             es_out_Send( p_demux->out, p_sys->p_es_audio, p_data );
 370         else
 371         {
 372             msg_Dbg( p_demux, "unsupported compression %c for audio (upload samples)", fh.i_compression );
 373             block_Release( p_data );
 374         }
 375     }
 376     else if( fh.i_type == 'V' && p_sys->p_es_video )
 377     {
 378         if( fh.i_compression >= '4' )
 379             es_out_Send( p_demux->out, p_sys->p_es_video, p_data );
 380         else
 381         {
 382             msg_Dbg( p_demux, "unsupported compression %c for video (upload samples)", fh.i_compression );
 383             block_Release( p_data );
 384         }
 385     }
 386     else
 387     {
 388         block_Release( p_data );
 389     }
 390
 391     return 1;
 392 }
 393
 394 /*****************************************************************************
 395  * Control:
 396  *****************************************************************************/
 397 static int Control( demux_t *p_demux, int i_query, va_list args )
 398 {
 399     demux_sys_t *p_sys  = p_demux->p_sys;
 400
 401     double   f, *pf;
 402     int64_t i64, *pi64;
 403
 404     switch( i_query )
 405     {
 406
 407         case DEMUX_GET_POSITION:
 408             pf = (double*)va_arg( args, double * );
 409             i64 = stream_Size( p_demux->s );
 410             if( i64 > 0 )
 411                 *pf = (double)stream_Tell( p_demux->s ) / (double)i64;
 412             else
 413                 *pf = 0.0;
 414             return VLC_SUCCESS;
 415
 416         case DEMUX_SET_POSITION:
 417         {
 418             int64_t i_pos;
 419
 420             f = (double)va_arg( args, double );
 421             i_pos = stream_Size( p_demux->s ) * f;
 422
 423             i64 = demux_IndexFindOffset( &p_sys->idx, i_pos );
 424
 425             p_sys->i_pcr = -1;
 426
 427             if( i64 >= 0 )
 428                 return stream_Seek( p_demux->s, i64 );
 429
 430             if( p_sys->idx.i_idx > 0 )
 431             {
 432                 if( stream_Seek( p_demux->s, p_sys->idx.idx[p_sys->idx.i_idx-1].i_offset ) )
 433                     return VLC_EGENERIC;
 434             }
 435             else
 436             {
 437                 if( stream_Seek( p_demux->s, 0 ) )
 438                     return VLC_EGENERIC;
 439             }
 440
 441             while( !p_demux->b_die )
 442             {
 443                 frame_header_t fh;
 444                 int64_t i_tell;
 445
 446                 if( ( i_tell = stream_Tell( p_demux->s ) ) >= i_pos )
 447                     break;
 448
 449                 if( FrameHeaderLoad( p_demux, &fh ) )
 450                     return VLC_EGENERIC;
 451
 452                 if( fh.i_type == 'A' || fh.i_type == 'V' )
 453                     demux_IndexAppend( &p_sys->idx,(int64_t)fh.i_timecode*1000, i_tell );
 454
 455                 if( fh.i_type != 'R' )
 456                     stream_Read( p_demux->s, NULL, fh.i_length );
 457             }
 458             return VLC_SUCCESS;
 459         }
 460
 461
 462         case DEMUX_GET_TIME:
 463             pi64 = (int64_t*)va_arg( args, int64_t * );
 464             *pi64 = p_sys->i_pcr >= 0 ? p_sys->i_pcr : 0;
 465             return VLC_SUCCESS;
 466
 467         case DEMUX_SET_TIME:
 468         {
 469             int64_t i_pos;
 470             i64 = (int64_t)va_arg( args, int64_t );
 471
 472             i_pos = demux_IndexConvertTime( &p_sys->idx, i64 );
 473             if( i_pos < 0 )
 474                 return VLC_EGENERIC;
 475
 476             if( stream_Seek( p_demux->s, i_pos ) )
 477                 return VLC_EGENERIC;
 478
 479             p_sys->i_pcr = -1;
 480
 481             while( !p_demux->b_die )
 482             {
 483                 frame_header_t fh;
 484
 485                 if( FrameHeaderLoad( p_demux, &fh ) )
 486                     return VLC_EGENERIC;
 487
 488                 if( fh.i_type == 'A' || fh.i_type == 'V' )
 489                 {
 490                     int64_t i_time = (int64_t)fh.i_timecode*1000;
 491                     int64_t i_tell = stream_Tell(p_demux->s)-12;
 492
 493                     demux_IndexAppend( &p_sys->idx, i_time, i_tell );
 494
 495                     if( i_time >= i64 )
 496                         return stream_Seek( p_demux->s, i_tell );
 497                 }
 498                 if( fh.i_type != 'R' )
 499                     stream_Read( p_demux->s, NULL, fh.i_length );
 500             }
 501             return VLC_SUCCESS;
 502         }
 503
 504         case DEMUX_GET_LENGTH:
 505             pi64 = (int64_t*)va_arg( args, int64_t * );
 506             return VLC_EGENERIC;
 507
 508         case DEMUX_GET_FPS:
 509             pf = (double*)va_arg( args, double * );
 510             *pf = p_sys->hdr.d_fps;
 511             return VLC_SUCCESS;
 512
 513         case DEMUX_GET_META:
 514         default:
 515             return VLC_EGENERIC;
 516
 517     }
 518 }
 519
 520 /*****************************************************************************
 521  *
 522  *****************************************************************************/
 523 static inline void GetDoubleLE( double *pd, void *src )
 524 {
 525     /* FIXME works only if sizeof(double) == 8 */
 526 #ifdef WORDS_BIGENDIAN
 527     uint8_t *p = (uint8_t*)pd, *q = (uint8_t*)src;
 528     int i;
 529     for( i = 0; i < 8; i++ )
 530         p[i] = q[7-i];
 531 #else
 532     memcpy( pd, src, 8 );
 533 #endif
 534 }
 535
 536 /* HeaderLoad:
 537  */
 538 static int HeaderLoad( demux_t *p_demux, header_t *h )
 539 {
 540     uint8_t buffer[72];
 541
 542     if( stream_Read( p_demux->s, buffer, 72 ) != 72 )
 543         return VLC_EGENERIC;
 544
 545     /* XXX: they are alignment to take care of (another broken format) */
 546     memcpy( h->id,      &buffer[ 0], 12 );
 547     memcpy( h->version, &buffer[12], 5 );
 548     h->i_width = GetDWLE( &buffer[20] );
 549     h->i_height = GetDWLE( &buffer[24] );
 550     h->i_width_desired = GetDWLE( &buffer[28] );
 551     h->i_height_desired = GetDWLE( &buffer[32] );
 552     h->i_mode = buffer[36];
 553     GetDoubleLE( &h->d_aspect, &buffer[40] );
 554     GetDoubleLE( &h->d_fps, &buffer[48] );
 555     h->i_video_blocks = GetDWLE( &buffer[56] );
 556     h->i_audio_blocks = GetDWLE( &buffer[60] );
 557     h->i_text_blocks = GetDWLE( &buffer[64] );
 558     h->i_keyframe_distance = GetDWLE( &buffer[68] );
 559 #if 0
 560     msg_Dbg( p_demux, "nuv: h=%s v=%s %dx%d a=%f fps=%f v=%d a=%d t=%d kfd=%d",
 561              h->id, h->version, h->i_width, h->i_height, h->d_aspect,
 562              h->d_fps, h->i_video_blocks, h->i_audio_blocks, h->i_text_blocks,
 563              h->i_keyframe_distance );
 564 #endif
 565     return VLC_SUCCESS;
 566 }
 567
 568 /* FrameHeaderLoad:
 569  */
 570 static int FrameHeaderLoad( demux_t *p_demux, frame_header_t *h )
 571 {
 572     uint8_t buffer[12];
 573
 574     if( stream_Read( p_demux->s, buffer, 12 ) != 12 )
 575         return VLC_EGENERIC;
 576
 577     h->i_type = buffer[0];
 578     h->i_compression = buffer[1];
 579     h->i_keyframe = buffer[2];
 580     h->i_filters = buffer[3];
 581
 582     h->i_timecode = GetDWLE( &buffer[4] );
 583     h->i_length = GetDWLE( &buffer[8] );
 584 #if 0
 585     msg_Dbg( p_demux, "frame hdr: t=%c c=%c k=%d f=0x%x timecode=%d l=%d",
 586              h->i_type,
 587              h->i_compression ? h->i_compression : ' ',
 588              h->i_keyframe ? h->i_keyframe : ' ',
 589              h->i_filters,
 590              h->i_timecode, h->i_length );
 591 #endif
 592     return VLC_SUCCESS;
 593 }
 594
 595 static int ExtendedHeaderLoad( demux_t *p_demux, extended_header_t *h )
 596 {
 597     uint8_t buffer[512];
 598
 599     if( stream_Read( p_demux->s, buffer, 512 ) != 512 )
 600         return VLC_EGENERIC;
 601
 602     h->i_version = GetDWLE( &buffer[0] );
 603     h->i_video_fcc = VLC_FOURCC( buffer[4], buffer[5], buffer[6], buffer[7] );
 604     h->i_audio_fcc = VLC_FOURCC( buffer[8], buffer[9], buffer[10], buffer[11] );
 605     h->i_audio_sample_rate = GetDWLE( &buffer[12] );
 606     h->i_audio_bits_per_sample = GetDWLE( &buffer[16] );
 607     h->i_audio_channels = GetDWLE( &buffer[20] );
 608     h->i_audio_compression_ratio = GetDWLE( &buffer[24] );
 609     h->i_audio_quality = GetDWLE( &buffer[28] );
 610     h->i_rtjpeg_quality = GetDWLE( &buffer[32] );
 611     h->i_rtjpeg_luma_filter = GetDWLE( &buffer[36] );
 612     h->i_rtjpeg_chroma_filter = GetDWLE( &buffer[40] );
 613     h->i_lavc_bitrate = GetDWLE( &buffer[44] );
 614     h->i_lavc_qmin = GetDWLE( &buffer[48] );
 615     h->i_lavc_qmin = GetDWLE( &buffer[52] );
 616     h->i_lavc_maxqdiff = GetDWLE( &buffer[56] );
 617     h->i_seekable_offset = GetQWLE( &buffer[60] );
 618     h->i_keyframe_adjust_offset= GetQWLE( &buffer[68] );
 619 #if 0
 620     msg_Dbg( p_demux, "ex hdr: v=%d vffc=%4.4s afcc=%4.4s %dHz %dbits ach=%d acr=%d aq=%d"
 621                       "rtjpeg q=%d lf=%d lc=%d lavc br=%d qmin=%d qmax=%d maxqdiff=%d seekableoff=%lld keyfao=%lld",
 622              h->i_version,
 623              (char*)&h->i_video_fcc,
 624              (char*)&h->i_audio_fcc, h->i_audio_sample_rate, h->i_audio_bits_per_sample, h->i_audio_channels,
 625              h->i_audio_compression_ratio, h->i_audio_quality,
 626              h->i_rtjpeg_quality, h->i_rtjpeg_luma_filter, h->i_rtjpeg_chroma_filter,
 627              h->i_lavc_bitrate, h->i_lavc_qmin, h->i_lavc_qmax, h->i_lavc_maxqdiff,
 628              h->i_seekable_offset, h->i_keyframe_adjust_offset );
 629 #endif
 630     return VLC_SUCCESS;
 631 }
 632
 633 /*****************************************************************************/
 634 #define DEMUX_INDEX_SIZE_MAX (100000)
 635 static void demux_IndexInit( demux_index_t *p_idx )
 636 {
 637     p_idx->i_idx = 0;
 638     p_idx->i_idx_max = 0;
 639     p_idx->idx = NULL;
 640 }
 641 static void demux_IndexClean( demux_index_t *p_idx )
 642 {
 643     if( p_idx->idx )
 644     {
 645         free( p_idx->idx );
 646         p_idx->idx = NULL;
 647     }
 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 }