summaryrefslogtreecommitdiffstats
path: root/libk3b/projects/videocd/mpeginfo/k3bmpeginfo.cpp
blob: 6192024e95b4d2e539b8ada9356639baa8452820 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
/*
*
* $Id: k3bmpeginfo.cpp 619556 2007-01-03 17:38:12Z trueg $
* Copyright (C) 2003-2004 Christian Kvasny <chris@k3b.org>
*
* This file is part of the K3b project.
* Copyright (C) 1998-2007 Sebastian Trueg <trueg@k3b.org>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
* See the file "COPYING" for the exact licensing terms.
*/

// kde includes
#include <klocale.h>

// k3b includes
#include "k3bmpeginfo.h"

static const double frame_rates[ 16 ] =
    {
        0.0, 24000.0 / 1001, 24.0, 25.0,
        30000.0 / 1001, 30.0, 50.0, 60000.0 / 1001,
        60.0, 0.0,
    };

K3bMpegInfo::K3bMpegInfo( const char* filename )
        : m_mpegfile( 0 ),
        m_filename( filename ),
        m_done( false ),
        m_buffstart( 0 ),
        m_buffend( 0 ),
        m_buffer( 0 ),
        m_initial_TS( 0.0 )
{

    mpeg_info = new Mpeginfo();

    m_mpegfile = fopen( filename, "rb" );

    if ( m_mpegfile == 0 ) {
        kdDebug() << TQString( "Unable to open %1" ).arg( m_filename ) << endl;
        return ;
    }

    if ( fseeko( m_mpegfile, 0, SEEK_END ) ) {
        kdDebug() << TQString( "Unable to seek in file %1" ).arg( m_filename ) << endl;
        return ;
    }

    llong lof = ftello( m_mpegfile );

    if ( lof == -1 ) {
        kdDebug() << TQString( "Seeking to end of input file %1 failed." ).arg( m_filename ) << endl;
        //give up..
        return ;
    } else
        m_filesize = lof;

    // nothing to do on an empty file
    if ( !m_filesize ) {
        kdDebug() << TQString( "File %1 is empty." ).arg( m_filename ) << endl;
        m_error_string = i18n( "File %1 is empty." ).arg( m_filename );
        return ;
    }

    m_buffer = new byte[ BUFFERSIZE ];

    MpegParsePacket ( );

}

K3bMpegInfo::~K3bMpegInfo()
{
    if ( m_buffer ) {
        delete[] m_buffer;
    }
    if ( m_mpegfile ) {
        fclose( m_mpegfile );
    }

    delete mpeg_info;
}
bool K3bMpegInfo::MpegParsePacket ()
{

    /* verify the packet begins with a pack header */
    if ( !EnsureMPEG( 0, MPEG_PACK_HEADER_CODE ) ) {
        llong code = GetNBytes( 0, 4 );

        kdDebug() << TQString( "(K3bMpegInfo::mpeg_parse_packet ()) pack header code 0x%1 expected, but 0x%2 found" ).arg( 0x00000100 + MPEG_PACK_HEADER_CODE, 0, 16 ).arg( code, 0, 16 ) << endl;

        if ( code == 0x00000100 + MPEG_SEQUENCE_CODE ) {
            kdDebug() << "...this looks like a elementary video stream but a multiplexed program stream was required." << endl;
            m_error_string = i18n( "This looks like a elementary video stream but a multiplexed program stream was required." );
        }

        if ( ( 0xfff00000 & code ) == 0xfff00000 ) {
            kdDebug() << "...this looks like a elementary audio stream but a multiplexed program stream was required." << endl;
            m_error_string = i18n( "This looks like a elementary audio stream but a multiplexed program stream was required." );
        }

        if ( code == 0x52494646 ) {
            kdDebug() << "...this looks like a RIFF header but a plain multiplexed program stream was required." << endl;
            m_error_string = i18n( "This looks like a RIFF header but a plain multiplexed program stream was required." );
        }

        return false;
    }


    /* take a look at the pack header */
    int offset = 0;
    while ( GetByte( offset ) == 0x00 )
        offset ++;
    //here we're on the first non null byte let's get back to leave two zeros (packet start code)
    offset -= 2;

    if ( offset != 0 ) {
        // we actually skipped some zeroes
        kdDebug() << TQString( "Skipped %1 zeroes at start of file" ).arg( offset ) << endl;
    }

    // here while schleife
    while ( offset != -1 ) {
        offset = MpegParsePacket( offset );
    }

    /*
        int pkt = 0;
        offset = FindNextMarker( 0, MPEG_PACK_HEADER_CODE );
     
        while ( offset != -1 ) {
            pkt++;
            offset = FindNextMarker( offset+1, MPEG_PACK_HEADER_CODE );
        }
     
        kdDebug() << "Pkt found: " << pkt << endl;
    */

    //seek the file duration by fetching the last PACK
    //and reading its timestamp
    llong last_pack = bdFindNextMarker( m_filesize - 13, MPEG_PACK_HEADER_CODE );
    // -12 because a PACK is at least 12 bytes
    double duration;
    last_pack += 4;
    int bits = GetByte( last_pack ) >> 4;

    if ( bits == 0x2 )                /* %0010 ISO11172-1 */
    {
        duration = ReadTS( last_pack );
    } else if ( bits >> 2 == 0x1 )                /* %01xx ISO13818-1 */
    {
        duration = ReadTSMpeg2( last_pack );
    } else {
        kdDebug() << TQString( "no timestamp found" ) << endl;
        duration = ReadTS( last_pack );
    }

    mpeg_info->playing_time = duration - m_initial_TS;


    if ( !mpeg_info->has_video )
        for ( int i = 0; i < 2; i++ )
            if ( mpeg_info->video[ i ].seen )
                mpeg_info->has_video = true;

    if ( !mpeg_info->has_audio )
        for ( int i = 0; i < 2; i++ )
            if ( mpeg_info->audio[ i ].seen )
                mpeg_info->has_audio = true;

    return true;
}

llong K3bMpegInfo::MpegParsePacket ( llong offset )
{
    byte mark = 0;
    uint size = 0;

    /* continue until start code seen */
    offset = FindNextMarker( offset, &mark );

    if ( offset < 0 )
        return offset;

    switch ( mark ) {
            int bits;

        case MPEG_PACK_HEADER_CODE:
            // kdDebug() << TQString( "MPEG_PACK_HEADER_CODE @ %1" ).arg( offset ) << endl;

            offset += 4;

            if ( mpeg_info->version != MPEG_VERS_INVALID )
                break;

            bits = GetByte( offset ) >> 4;

            if ( bits == 0x2 )                /* %0010 ISO11172-1 */
            {
                mpeg_info->version = MPEG_VERS_MPEG1;

                unsigned long muxrate = 0;

                muxrate = ( GetByte( offset + 5 ) & 0x7F ) << 15;
                muxrate |= ( GetByte( offset + 6 ) << 7 );
                muxrate |= ( GetByte( offset + 7 ) >> 1 );

                mpeg_info->muxrate = muxrate * 50 * 8;

                if ( m_initial_TS == 0.0 )
                {
                    m_initial_TS = ReadTS( offset );
                    kdDebug() << TQString( "Initial TS = %1" ).arg( m_initial_TS ) << endl;
                }

            } else if ( bits >> 2 == 0x1 )                /* %01xx ISO13818-1 */
            {
                mpeg_info->version = MPEG_VERS_MPEG2;

                unsigned long muxrate = 0;
                muxrate = GetByte( offset + 6 ) << 14;
                muxrate |= GetByte( offset + 7 ) << 6;
                muxrate |= GetByte( offset + 8 ) >> 2;

                mpeg_info->muxrate = muxrate * 50 * 8;

                if ( m_initial_TS == 0.0 )
                {
                    m_initial_TS = ReadTSMpeg2( offset );
                    kdDebug() << TQString( "Initial TS = %1" ).arg( m_initial_TS ) << endl;
                }

            } else {
                kdDebug() << TQString( "packet not recognized as either version 1 or 2 (%1)" ).arg( bits ) << endl;
                mpeg_info->version = MPEG_VERS_INVALID;
                return -1;
            }
            break;

        case MPEG_SYSTEM_HEADER_CODE:
        case MPEG_PAD_CODE:
        case MPEG_PRIVATE_1_CODE:
        case MPEG_VIDEO_E0_CODE:
        case MPEG_VIDEO_E1_CODE:
        case MPEG_VIDEO_E2_CODE:
        case MPEG_AUDIO_C0_CODE:
        case MPEG_AUDIO_C1_CODE:
        case MPEG_AUDIO_C2_CODE:

            offset += 4;
            size = GetSize( offset );
            offset += 2;
            // kdDebug() << TQString( "offset = %1, size = %2" ).arg( offset ).arg( size ) << endl;

            switch ( mark ) {
                case MPEG_SYSTEM_HEADER_CODE:
                    // kdDebug() << TQString( "Systemheader: %1" ).arg( m_code, 0, 16 ) << endl;
                    break;

                case MPEG_VIDEO_E0_CODE:
                case MPEG_VIDEO_E1_CODE:
                case MPEG_VIDEO_E2_CODE:
                    ParseVideo( offset, mark );
                    // _analyze_video_pes (code & 0xff, buf + pos, size, !parse_pes, ctx);
                    if ( mpeg_info->has_video && mpeg_info->has_audio ) {
                        return -1;
                    } else if ( mark == MPEG_VIDEO_E0_CODE || mpeg_info->version == MPEG_VERS_MPEG2 && mark == MPEG_VIDEO_E1_CODE || mpeg_info->version == MPEG_VERS_MPEG1 && mark == MPEG_VIDEO_E2_CODE ) {
                        mpeg_info->has_video = true;
                        offset = FindNextAudio( offset );
                    }
                    break;
                case MPEG_AUDIO_C0_CODE:
                case MPEG_AUDIO_C1_CODE:
                case MPEG_AUDIO_C2_CODE:
                    offset = SkipPacketHeader( offset - 6 );
                    ParseAudio( offset, mark );
                    // audio packet doesn't begin with 0xFFF
                    if ( !mpeg_info->audio[ GetAudioIdx( mark ) ].seen ) {
                        int a_idx = GetAudioIdx( mark );
                        while ( ( offset < m_filesize - 10 ) && !mpeg_info->audio[ a_idx ].seen ) {
                            if ( ( GetByte( offset ) == 0xFF ) && ( GetByte( offset + 1 ) & 0xF0 ) == 0xF0 )
                                ParseAudio( offset, mark );
                            offset++;
                        }
                    }

                    mpeg_info->has_audio = true;
                    if ( mpeg_info->has_video )
                        return -1;

                    offset = FindNextVideo( offset );
                    break;

                case MPEG_PRIVATE_1_CODE:
                    kdDebug() << TQString( "PrivateCode: %1" ).arg( mark, 0, 16 ) << endl;
                    break;
            }
            break;

        case MPEG_PROGRAM_END_CODE:
            kdDebug() << TQString( "ProgramEndCode: %1" ).arg( mark, 0, 16 ) << endl;
            offset += 4;
            break;

        case MPEG_PICTURE_CODE:
            kdDebug() << TQString( "PictureCode: %1" ).arg( mark, 0, 16 ) << endl;
            offset += 3;
            break;

        default:
            offset += 4;
            break;
    }

    return offset;
}

byte K3bMpegInfo::GetByte( llong offset )
{
    unsigned long nread;
    if ( ( offset >= m_buffend ) || ( offset < m_buffstart ) ) {

        if ( fseeko( m_mpegfile, offset, SEEK_SET ) ) {
            kdDebug() << TQString( "could not get seek to offset (%1) in file %2 (size:%3)" ).arg( offset ).arg( m_filename ).arg( m_filesize ) << endl;
            return 0x11;
        }
        nread = fread( m_buffer, 1, BUFFERSIZE, m_mpegfile );
        m_buffstart = offset;
        m_buffend = offset + nread;
        if ( ( offset >= m_buffend ) || ( offset < m_buffstart ) ) {
            // weird
            kdDebug() << TQString( "could not get offset %1 in file %2 [%3]" ).arg( offset ).arg( m_filename ).arg( m_filesize ) << endl;
            return 0x11;
        }
    }
    return m_buffer[ offset - m_buffstart ];
}

// same as above but improved for backward search
byte K3bMpegInfo::bdGetByte( llong offset )
{
    unsigned long nread;
    if ( ( offset >= m_buffend ) || ( offset < m_buffstart ) ) {
        llong start = offset - BUFFERSIZE + 1 ;
        start = start >= 0 ? start : 0;

        fseeko( m_mpegfile, start, SEEK_SET );

        nread = fread( m_buffer, 1, BUFFERSIZE, m_mpegfile );
        m_buffstart = start;
        m_buffend = start + nread;
        if ( ( offset >= m_buffend ) || ( offset < m_buffstart ) ) {
            // weird
            kdDebug() << TQString( "could not get offset %1 in file %2 [%3]" ).arg( offset ).arg( m_filename ).arg( m_filesize ) << endl;

            return 0x11;
        }
    }
    return m_buffer[ offset - m_buffstart ];
}


llong K3bMpegInfo::GetNBytes( llong offset, int n )
{
    llong nbytes = 0;
    n--;
    for ( int i = 0; i < n; i++ )
        ( ( char* ) & nbytes ) [ n - i ] = GetByte( offset + i );

    return nbytes;

}

// get a two byte size
unsigned short int K3bMpegInfo::GetSize( llong offset )
{
    return GetByte( offset ) * 256 + GetByte( offset + 1 );
    // return GetNBytes( offset, 2 );

}

bool K3bMpegInfo::EnsureMPEG( llong offset, byte mark )
{
    if ( ( GetByte( offset ) == 0x00 ) &&
            ( GetByte( offset + 1 ) == 0x00 ) &&
            ( GetByte( offset + 2 ) == 0x01 ) &&
            ( GetByte( offset + 3 ) == mark ) )
        return true;
    else
        return false;
}


// find next 0x 00 00 01 xx sequence, returns offset or -1 on err
llong K3bMpegInfo::FindNextMarker( llong from )
{
    llong offset;
    for ( offset = from; offset < ( m_filesize - 4 ); offset++ ) {
        if (
            ( GetByte( offset + 0 ) == 0x00 ) &&
            ( GetByte( offset + 1 ) == 0x00 ) &&
            ( GetByte( offset + 2 ) == 0x01 ) ) {
            return offset;
        }
    }
    return -1;
}

// find next 0x 00 00 01 xx sequence, returns offset or -1 on err and
// change mark to xx
llong K3bMpegInfo::FindNextMarker( llong from, byte* mark )
{
    llong offset = FindNextMarker( from );
    if ( offset >= 0 ) {
        *mark = GetByte( offset + 3 );
        return offset;
    } else {
        return -1;
    }
}

// find next 0X00 00 01 mark
llong K3bMpegInfo::FindNextMarker( llong from, byte mark )
{
    llong offset = from;
    while ( offset >= 0 ) {
        offset = FindNextMarker( offset );
        if ( offset < 0 ) {
            return -1;
        }
        if ( EnsureMPEG( offset, mark ) ) {
            return offset;
        } else
            offset++;
    }

    //shouldn't be here
    return -1;
}

llong K3bMpegInfo::bdFindNextMarker( llong from, byte mark )
{
    llong offset;
    for ( offset = from; offset >= 0; offset-- ) {
        if (
            ( bdGetByte( offset ) == 0x00 ) &&
            ( bdGetByte( offset + 1 ) == 0x00 ) &&
            ( bdGetByte( offset + 2 ) == 0x01 ) &&
            ( bdGetByte( offset + 3 ) == mark ) ) {
            return offset;
        }
    }
    return -1;
}

llong K3bMpegInfo::bdFindNextMarker( llong from, byte* mark )
{
    llong offset;
    for ( offset = from; offset >= 0; offset-- ) {
        if ( ( bdGetByte( offset ) == 0x00 ) &&
                ( bdGetByte( offset + 1 ) == 0x00 ) &&
                ( bdGetByte( offset + 2 ) == 0x01 ) ) {
            *mark = bdGetByte( offset + 3 );
            return offset;
        }
    }
    return -1;

}

llong K3bMpegInfo::FindNextVideo( llong from )
{
    llong offset = from;
    while ( offset >= 0 ) {
        offset = FindNextMarker( offset );
        if ( offset < 0 ) {
            return -1;
        }
        if ( EnsureMPEG( offset, MPEG_VIDEO_E0_CODE ) || EnsureMPEG( offset, MPEG_VIDEO_E1_CODE ) || EnsureMPEG( offset, MPEG_VIDEO_E2_CODE ) ) {
            return offset;
        } else
            offset++;
    }

    //shouldn't be here
    return -1;
}

llong K3bMpegInfo::FindNextAudio( llong from )
{
    llong offset = from;
    while ( offset >= 0 ) {
        offset = FindNextMarker( offset );
        if ( offset < 0 ) {
            return -1;
        }
        if ( EnsureMPEG( offset, MPEG_AUDIO_C0_CODE ) || EnsureMPEG( offset, MPEG_AUDIO_C1_CODE ) || EnsureMPEG( offset, MPEG_AUDIO_C2_CODE ) ) {
            return offset;
        } else
            offset++;
    }

    return -1;
}


int K3bMpegInfo::GetVideoIdx ( byte marker )
{
    switch ( marker ) {
        case MPEG_VIDEO_E0_CODE:
            return 0;
            break;

        case MPEG_VIDEO_E1_CODE:
            return 1;
            break;

        case MPEG_VIDEO_E2_CODE:
            return 2;
            break;

        default:
            kdDebug() << "VideoCode not reached" << endl;
            break;
    }

    return -1;
}

int K3bMpegInfo::GetAudioIdx ( byte marker )
{
    switch ( marker ) {
        case MPEG_AUDIO_C0_CODE:
            return 0;
            break;

        case MPEG_AUDIO_C1_CODE:
            return 1;
            break;

        case MPEG_AUDIO_C2_CODE:
            return 2;
            break;

        default:
            kdDebug() << "VideoCode not reached" << endl;
            break;
    }

    return -1;
}

llong K3bMpegInfo::SkipPacketHeader( llong offset )
{
    byte tmp_byte;
    if ( mpeg_info->version == MPEG_VERS_MPEG1 ) {
        // skip startcode and packet size
        offset += 6;
        //remove stuffing bytes
        tmp_byte = GetByte( offset );
        while ( tmp_byte & 0x80 )
            tmp_byte = GetByte( ++offset );

        if ( ( tmp_byte & 0xC0 ) == 0x40 )                // next two bits are 01
            offset += 2;

        tmp_byte = GetByte( offset );
        if ( ( tmp_byte & 0xF0 ) == 0x20 )
            offset += 5;
        else if ( ( tmp_byte & 0xF0 ) == 0x30 )
            offset += 10;
        else
            offset++;

        return offset;
    } else if ( mpeg_info->version == MPEG_VERS_MPEG2 ) {
        return ( offset + 9 + GetByte( offset + 8 ) );
    } else
        return ( offset + 10 );
}

void K3bMpegInfo::ParseAudio ( llong offset, byte marker )
{
    unsigned brate, srate;
    bool mpeg2_5 = false;

    const int a_idx = GetAudioIdx( marker );

    if ( mpeg_info->audio[ a_idx ].seen )                /* we have it already */
        return ;

    if ( ( GetByte( offset ) != 0xFF ) || ( ( GetByte( offset + 1 ) & 0xF0 ) != 0xF0 ) ) {
        // doesn't start with 12 bits set
        if ( ( GetByte( offset ) != 0xFF ) || ( ( GetByte( offset + 1 ) & 0xE0 ) != 0xE0 ) ) {
            // doesn't start with 11 bits set
            return ;
        } else {
            // start with 11 bits set
            mpeg2_5 = true;
        }
    }

    // Find mpeg version 1.0 or 2.0
    if ( GetByte( offset + 1 ) & 0x08 ) {
        if ( !mpeg2_5 )
            mpeg_info->audio[ a_idx ].version = 1;
        else
            return ; // invalid 01 encountered
    } else {
        if ( !mpeg2_5 )
            mpeg_info->audio[ a_idx ].version = 2;
        else
            mpeg_info->audio[ a_idx ].version = 3; //for mpeg 2.5
    }

    // Find Layer
    mpeg_info->audio[ a_idx ].layer = ( GetByte( offset + 1 ) & 0x06 ) >> 1;
    switch ( mpeg_info->audio[ a_idx ].layer ) {
        case 0:
            mpeg_info->audio[ a_idx ].layer = 0;
            break;
        case 1:
            mpeg_info->audio[ a_idx ].layer = 3;
            break;
        case 2:
            mpeg_info->audio[ a_idx ].layer = 2;
            break;
        case 3:
            mpeg_info->audio[ a_idx ].layer = 1;
            break;
    }

    // Protection Bit
    mpeg_info->audio[ a_idx ].protect = GetByte( offset + 1 ) & 0x01;
    if ( mpeg_info->audio[ a_idx ].protect )
        mpeg_info->audio[ a_idx ].protect = 0;
    else
        mpeg_info->audio[ a_idx ].protect = 1;

    const unsigned bit_rates[ 4 ][ 16 ] = {
                                              {
                                                  0,
                                              },
                                              {0, 32, 64, 96, 128, 160, 192, 224, 256, 288, 320, 352, 384, 416, 448, 0},
                                              {0, 32, 48, 56, 64, 80, 96, 112, 128, 160, 192, 224, 256, 320, 384, 0},
                                              {0, 32, 40, 48, 56, 64, 80, 96, 112, 128, 160, 192, 224, 256, 320, 0}
                                          };


    /*  const unsigned bit_rates [ 3 ][ 3 ][ 16 ] = {
        {
          {0, },
          {0, },
          {0, },
        },
        {
          {0, 32, 64, 96, 128, 160, 192, 224, 256, 288, 320, 352, 384, 416, 448, 0},
          {0, 32, 48, 56, 64, 80, 96, 112, 128, 160, 192, 224, 256, 320, 384, 0},
          {0, 32, 40, 48, 56, 64, 80, 96, 112, 128, 160, 192, 224, 256, 320, 0}
        },
        {
          {0, 32, 48, 56, 64, 80 , 96 , 112, 128, 144, 160, 176, 192, 224, 256, 0},
          {0, 8, 16, 24, 32, 40, 48, 56, 64 , 80 , 96 , 112, 128, 144, 160, 0},
          {0, 8, 16, 24, 32, 40, 48, 56, 64 , 80 , 96 , 112, 128, 144, 160, 0}
        }
      };
    */

    const unsigned sampling_rates[ 4 ][ 4 ] = {
                {
                    0,
                },
                {44100, 48000, 32000, 0},                //mpeg 1
                {22050, 24000, 16000, 0},                //mpeg 2
                {11025, 12000, 8000, 0}   //mpeg 2.5
            };


    // Bitrate index and sampling index to pass through the array
    brate = GetByte( offset + 2 ) >> 4;
    srate = ( GetByte( offset + 2 ) & 0x0f ) >> 2;

    mpeg_info->audio[ a_idx ].bitrate = 1024 * bit_rates[ mpeg_info->audio[ a_idx ].layer ][ brate ];
    mpeg_info->audio[ a_idx ].byterate = ( float ) ( mpeg_info->audio[ a_idx ].bitrate / 8.0 );
    mpeg_info->audio[ a_idx ].sampfreq = sampling_rates[ mpeg_info->audio[ a_idx ].version ][ srate ];

    // Audio mode
    mpeg_info->audio[ a_idx ].mode = 1 + ( GetByte( offset + 3 ) >> 6 ) ;

    // Copyright bit
    if ( GetByte( offset + 3 ) & 0x08 )
        mpeg_info->audio[ a_idx ].copyright = true;
    else
        mpeg_info->audio[ a_idx ].copyright = false;

    // Original/Copy bit
    if ( GetByte( offset + 3 ) & 0x04 )
        mpeg_info->audio[ a_idx ].original = true;
    else
        mpeg_info->audio[ a_idx ].original = false;


    mpeg_info->audio[ a_idx ].seen = true;
}

void K3bMpegInfo::ParseVideo ( llong offset, byte marker )
{
    unsigned long aratio, frate, brate;

    const int v_idx = GetVideoIdx( marker );

    const double aspect_ratios[ 16 ] = {
                                           0.0000, 1.0000, 0.6735, 0.7031,
                                           0.7615, 0.8055, 0.8437, 0.8935,
                                           0.9375, 0.9815, 1.0255, 1.0695,
                                           1.1250, 1.1575, 1.2015, 0.0000
                                       };

    if ( mpeg_info->video[ v_idx ].seen )                /* we have it already */
        return ;

    offset = FindNextMarker( offset + 1, MPEG_SEQUENCE_CODE );

    if ( !offset )
        return ;

    offset += 4;

    mpeg_info->video[ v_idx ].hsize = GetSize( offset ) >> 4;
    mpeg_info->video[ v_idx ].vsize = GetSize( offset + 1 ) & 0x0FFF;

    // Get picture rate
    offset += 3; // after picture sizes

    aratio = ( GetByte( offset ) & 0x0F ) >> 4;
    mpeg_info->video[ v_idx ].aratio = aspect_ratios[ aratio ];

    //    offset += 3; // after picture sizes
    frate = GetByte( offset ) & 0x0F;
    mpeg_info->video[ v_idx ].frate = frame_rates[ frate ];

    offset += 1; // after picture rate

    // 18 following bytes are the bitrate /400

    //read first 16 bytes
    brate = GetSize( offset );
    // scale
    brate <<= 2;
    byte lasttwo = GetByte( offset + 2 );
    lasttwo >>= 6;
    brate |= lasttwo;

    mpeg_info->video[ v_idx ].bitrate = 400 * brate;

    byte mark;
    while ( true ) {
        offset = FindNextMarker( offset, &mark );
        if ( mark == MPEG_GOP_CODE )
            break;
        switch ( GetByte( offset + 3 ) ) {
            case MPEG_EXT_CODE :
                // Extension
                offset += 4;
                switch ( GetByte( offset ) >> 4 ) {
                    case 1:
                        //SequenceExt
                        if ( GetByte( offset + 1 ) & 0x08 )
                            mpeg_info->video[ v_idx ].progressive = true;
                        mpeg_info->video[ v_idx ].chroma_format = ( GetByte( offset + 1 ) & 0x06 ) >> 1;
                        break;
                    case 2:
                        // SequenceDisplayExt
                        mpeg_info->video[ v_idx ].video_format = ( GetByte( offset ) & 0x0E ) >> 1;
                        break;
                }

                break;
            case MPEG_USER_CODE :
                // UserData
                break;
        }
        offset++;
    }

    mpeg_info->video[ v_idx ].seen = true;
}

double K3bMpegInfo::ReadTS( llong offset )
{
    byte highbit;
    unsigned long low4Bytes;
    double TS;

    highbit = ( GetByte( offset ) >> 3 ) & 0x01;

    low4Bytes = ( ( GetByte( offset ) >> 1 ) & 0x03 ) << 30;
    low4Bytes |= GetByte( offset + 1 ) << 22;
    low4Bytes |= ( GetByte( offset + 2 ) >> 1 ) << 15;
    low4Bytes |= GetByte( offset + 3 ) << 7;
    low4Bytes |= GetByte( offset + 4 ) >> 1;


    TS = ( double ) ( highbit * FLOAT_0x10000 * FLOAT_0x10000 );
    TS += ( double ) ( low4Bytes );
    TS /= ( double ) ( STD_SYSTEM_CLOCK_FREQ );

    return TS;
}

double K3bMpegInfo::ReadTSMpeg2( llong offset )
{
    byte highbit;
    unsigned long low4Bytes;
    unsigned long sys_clock_ref;
    double TS;

    highbit = ( GetByte( offset ) & 0x20 ) >> 5;

    low4Bytes = ( ( GetByte( offset ) & 0x18 ) >> 3 ) << 30;
    low4Bytes |= ( GetByte( offset ) & 0x03 ) << 28;
    low4Bytes |= GetByte( offset + 1 ) << 20;
    low4Bytes |= ( GetByte( offset + 2 ) & 0xF8 ) << 12;
    low4Bytes |= ( GetByte( offset + 2 ) & 0x03 ) << 13;
    low4Bytes |= GetByte( offset + 3 ) << 5;
    low4Bytes |= ( GetByte( offset + 4 ) ) >> 3;

    sys_clock_ref = ( GetByte( offset + 4 ) & 0x3 ) << 7;
    sys_clock_ref |= ( GetByte( offset + 5 ) >> 1 );

    TS = ( double ) ( highbit * FLOAT_0x10000 * FLOAT_0x10000 );
    TS += ( double ) ( low4Bytes );
    if ( sys_clock_ref == 0 )
        TS /= ( double ) ( STD_SYSTEM_CLOCK_FREQ );
    else {
        TS /= ( double ) ( 27000000 / sys_clock_ref );
    }

    return TS;
}