libavformat/mp3.c

   1 /*
   2  * MP3 muxer and demuxer
   3  * Copyright (c) 2003 Fabrice Bellard.
   4  *
   5  * This file is part of FFmpeg.
   6  *
   7  * FFmpeg is free software; you can redistribute it and/or
   8  * modify it under the terms of the GNU Lesser General Public
   9  * License as published by the Free Software Foundation; either
  10  * version 2.1 of the License, or (at your option) any later version.
  11  *
  12  * FFmpeg is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  15  * Lesser General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU Lesser General Public
  18  * License along with FFmpeg; if not, write to the Free Software
  19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  20  */
  21
  22 #include "libavutil/avstring.h"
  23 #include "libavcodec/mpegaudio.h"
  24 #include "libavcodec/mpegaudiodecheader.h"
  25 #include "avformat.h"
  26
  27 #define ID3v2_HEADER_SIZE 10
  28 #define ID3v1_TAG_SIZE 128
  29
  30 #define ID3v1_GENRE_MAX 125
  31
  32 static const char *id3v1_genre_str[ID3v1_GENRE_MAX + 1] = {
  33     [0] = "Blues",
  34     [1] = "Classic Rock",
  35     [2] = "Country",
  36     [3] = "Dance",
  37     [4] = "Disco",
  38     [5] = "Funk",
  39     [6] = "Grunge",
  40     [7] = "Hip-Hop",
  41     [8] = "Jazz",
  42     [9] = "Metal",
  43     [10] = "New Age",
  44     [11] = "Oldies",
  45     [12] = "Other",
  46     [13] = "Pop",
  47     [14] = "R&B",
  48     [15] = "Rap",
  49     [16] = "Reggae",
  50     [17] = "Rock",
  51     [18] = "Techno",
  52     [19] = "Industrial",
  53     [20] = "Alternative",
  54     [21] = "Ska",
  55     [22] = "Death Metal",
  56     [23] = "Pranks",
  57     [24] = "Soundtrack",
  58     [25] = "Euro-Techno",
  59     [26] = "Ambient",
  60     [27] = "Trip-Hop",
  61     [28] = "Vocal",
  62     [29] = "Jazz+Funk",
  63     [30] = "Fusion",
  64     [31] = "Trance",
  65     [32] = "Classical",
  66     [33] = "Instrumental",
  67     [34] = "Acid",
  68     [35] = "House",
  69     [36] = "Game",
  70     [37] = "Sound Clip",
  71     [38] = "Gospel",
  72     [39] = "Noise",
  73     [40] = "AlternRock",
  74     [41] = "Bass",
  75     [42] = "Soul",
  76     [43] = "Punk",
  77     [44] = "Space",
  78     [45] = "Meditative",
  79     [46] = "Instrumental Pop",
  80     [47] = "Instrumental Rock",
  81     [48] = "Ethnic",
  82     [49] = "Gothic",
  83     [50] = "Darkwave",
  84     [51] = "Techno-Industrial",
  85     [52] = "Electronic",
  86     [53] = "Pop-Folk",
  87     [54] = "Eurodance",
  88     [55] = "Dream",
  89     [56] = "Southern Rock",
  90     [57] = "Comedy",
  91     [58] = "Cult",
  92     [59] = "Gangsta",
  93     [60] = "Top 40",
  94     [61] = "Christian Rap",
  95     [62] = "Pop/Funk",
  96     [63] = "Jungle",
  97     [64] = "Native American",
  98     [65] = "Cabaret",
  99     [66] = "New Wave",
 100     [67] = "Psychadelic",
 101     [68] = "Rave",
 102     [69] = "Showtunes",
 103     [70] = "Trailer",
 104     [71] = "Lo-Fi",
 105     [72] = "Tribal",
 106     [73] = "Acid Punk",
 107     [74] = "Acid Jazz",
 108     [75] = "Polka",
 109     [76] = "Retro",
 110     [77] = "Musical",
 111     [78] = "Rock & Roll",
 112     [79] = "Hard Rock",
 113     [80] = "Folk",
 114     [81] = "Folk-Rock",
 115     [82] = "National Folk",
 116     [83] = "Swing",
 117     [84] = "Fast Fusion",
 118     [85] = "Bebob",
 119     [86] = "Latin",
 120     [87] = "Revival",
 121     [88] = "Celtic",
 122     [89] = "Bluegrass",
 123     [90] = "Avantgarde",
 124     [91] = "Gothic Rock",
 125     [92] = "Progressive Rock",
 126     [93] = "Psychedelic Rock",
 127     [94] = "Symphonic Rock",
 128     [95] = "Slow Rock",
 129     [96] = "Big Band",
 130     [97] = "Chorus",
 131     [98] = "Easy Listening",
 132     [99] = "Acoustic",
 133     [100] = "Humour",
 134     [101] = "Speech",
 135     [102] = "Chanson",
 136     [103] = "Opera",
 137     [104] = "Chamber Music",
 138     [105] = "Sonata",
 139     [106] = "Symphony",
 140     [107] = "Booty Bass",
 141     [108] = "Primus",
 142     [109] = "Porn Groove",
 143     [110] = "Satire",
 144     [111] = "Slow Jam",
 145     [112] = "Club",
 146     [113] = "Tango",
 147     [114] = "Samba",
 148     [115] = "Folklore",
 149     [116] = "Ballad",
 150     [117] = "Power Ballad",
 151     [118] = "Rhythmic Soul",
 152     [119] = "Freestyle",
 153     [120] = "Duet",
 154     [121] = "Punk Rock",
 155     [122] = "Drum Solo",
 156     [123] = "A capella",
 157     [124] = "Euro-House",
 158     [125] = "Dance Hall",
 159 };
 160
 161 /* buf must be ID3v2_HEADER_SIZE byte long */
 162 static int id3v2_match(const uint8_t *buf)
 163 {
 164     return  buf[0] == 'I' &&
 165             buf[1] == 'D' &&
 166             buf[2] == '3' &&
 167             buf[3] != 0xff &&
 168             buf[4] != 0xff &&
 169             (buf[6] & 0x80) == 0 &&
 170             (buf[7] & 0x80) == 0 &&
 171             (buf[8] & 0x80) == 0 &&
 172             (buf[9] & 0x80) == 0;
 173 }
 174
 175 static unsigned int id3v2_get_size(ByteIOContext *s, int len)
 176 {
 177     int v=0;
 178     while(len--)
 179         v= (v<<7) + (get_byte(s)&0x7F);
 180     return v;
 181 }
 182
 183 static void id3v2_read_ttag(AVFormatContext *s, int taglen, char *dst, int dstlen)
 184 {
 185     char *q;
 186     int len;
 187
 188     if(taglen < 1)
 189         return;
 190
 191     taglen--; /* account for encoding type byte */
 192     dstlen--; /* Leave space for zero terminator */
 193
 194     switch(get_byte(s->pb)) { /* encoding type */
 195
 196     case 0:  /* ISO-8859-1 (0 - 255 maps directly into unicode) */
 197         q = dst;
 198         while(taglen--) {
 199             uint8_t tmp;
 200             PUT_UTF8(get_byte(s->pb), tmp, if (q - dst < dstlen - 1) *q++ = tmp;)
 201         }
 202         *q = '\0';
 203         break;
 204
 205     case 3:  /* UTF-8 */
 206         len = FFMIN(taglen, dstlen);
 207         get_buffer(s->pb, dst, len);
 208         dst[len] = 0;
 209         break;
 210     }
 211 }
 212
 213 /**
 214  * ID3v2 parser
 215  *
 216  * Handles ID3v2.2, 2.3 and 2.4.
 217  *
 218  */
 219
 220 static void id3v2_parse(AVFormatContext *s, int len, uint8_t version, uint8_t flags)
 221 {
 222     int isv34, tlen;
 223     uint32_t tag;
 224     offset_t next;
 225     char tmp[16];
 226     int taghdrlen;
 227     const char *reason;
 228
 229     switch(version) {
 230     case 2:
 231         if(flags & 0x40) {
 232             reason = "compression";
 233             goto error;
 234         }
 235         isv34 = 0;
 236         taghdrlen = 6;
 237         break;
 238
 239     case 3:
 240     case 4:
 241         isv34 = 1;
 242         taghdrlen = 10;
 243         break;
 244
 245     default:
 246         reason = "version";
 247         goto error;
 248     }
 249
 250     if(flags & 0x80) {
 251         reason = "unsynchronization";
 252         goto error;
 253     }
 254
 255     if(isv34 && flags & 0x40) /* Extended header present, just skip over it */
 256         url_fskip(s->pb, id3v2_get_size(s->pb, 4));
 257
 258     while(len >= taghdrlen) {
 259         if(isv34) {
 260             tag  = get_be32(s->pb);
 261             tlen = id3v2_get_size(s->pb, 4);
 262             get_be16(s->pb); /* flags */
 263         } else {
 264             tag  = get_be24(s->pb);
 265             tlen = id3v2_get_size(s->pb, 3);
 266         }
 267         len -= taghdrlen + tlen;
 268
 269         if(len < 0)
 270             break;
 271
 272         next = url_ftell(s->pb) + tlen;
 273
 274         switch(tag) {
 275         case MKBETAG('T', 'I', 'T', '2'):
 276         case MKBETAG(0,   'T', 'T', '2'):
 277             id3v2_read_ttag(s, tlen, s->title, sizeof(s->title));
 278             break;
 279         case MKBETAG('T', 'P', 'E', '1'):
 280         case MKBETAG(0,   'T', 'P', '1'):
 281             id3v2_read_ttag(s, tlen, s->author, sizeof(s->author));
 282             break;
 283         case MKBETAG('T', 'A', 'L', 'B'):
 284         case MKBETAG(0,   'T', 'A', 'L'):
 285             id3v2_read_ttag(s, tlen, s->album, sizeof(s->album));
 286             break;
 287         case MKBETAG('T', 'C', 'O', 'N'):
 288         case MKBETAG(0,   'T', 'C', 'O'):
 289             id3v2_read_ttag(s, tlen, s->genre, sizeof(s->genre));
 290             break;
 291         case MKBETAG('T', 'C', 'O', 'P'):
 292         case MKBETAG(0,   'T', 'C', 'R'):
 293             id3v2_read_ttag(s, tlen, s->copyright, sizeof(s->copyright));
 294             break;
 295         case MKBETAG('T', 'R', 'C', 'K'):
 296         case MKBETAG(0,   'T', 'R', 'K'):
 297             id3v2_read_ttag(s, tlen, tmp, sizeof(tmp));
 298             s->track = atoi(tmp);
 299             break;
 300         case 0:
 301             /* padding, skip to end */
 302             url_fskip(s->pb, len);
 303             len = 0;
 304             continue;
 305         }
 306         /* Skip to end of tag */
 307         url_fseek(s->pb, next, SEEK_SET);
 308     }
 309
 310     if(version == 4 && flags & 0x10) /* Footer preset, always 10 bytes, skip over it */
 311         url_fskip(s->pb, 10);
 312     return;
 313
 314   error:
 315     av_log(s, AV_LOG_INFO, "ID3v2.%d tag skipped, cannot handle %s\n", version, reason);
 316     url_fskip(s->pb, len);
 317 }
 318
 319 static void id3v1_get_string(char *str, int str_size,
 320                              const uint8_t *buf, int buf_size)
 321 {
 322     int i, c;
 323     char *q;
 324
 325     q = str;
 326     for(i = 0; i < buf_size; i++) {
 327         c = buf[i];
 328         if (c == '\0')
 329             break;
 330         if ((q - str) >= str_size - 1)
 331             break;
 332         *q++ = c;
 333     }
 334     *q = '\0';
 335 }
 336
 337 /* 'buf' must be ID3v1_TAG_SIZE byte long */
 338 static int id3v1_parse_tag(AVFormatContext *s, const uint8_t *buf)
 339 {
 340     char str[5];
 341     int genre;
 342
 343     if (!(buf[0] == 'T' &&
 344           buf[1] == 'A' &&
 345           buf[2] == 'G'))
 346         return -1;
 347     id3v1_get_string(s->title, sizeof(s->title), buf + 3, 30);
 348     id3v1_get_string(s->author, sizeof(s->author), buf + 33, 30);
 349     id3v1_get_string(s->album, sizeof(s->album), buf + 63, 30);
 350     id3v1_get_string(str, sizeof(str), buf + 93, 4);
 351     s->year = atoi(str);
 352     id3v1_get_string(s->comment, sizeof(s->comment), buf + 97, 30);
 353     if (buf[125] == 0 && buf[126] != 0)
 354         s->track = buf[126];
 355     genre = buf[127];
 356     if (genre <= ID3v1_GENRE_MAX)
 357         av_strlcpy(s->genre, id3v1_genre_str[genre], sizeof(s->genre));
 358     return 0;
 359 }
 360
 361 static void id3v1_create_tag(AVFormatContext *s, uint8_t *buf)
 362 {
 363     int v, i;
 364
 365     memset(buf, 0, ID3v1_TAG_SIZE); /* fail safe */
 366     buf[0] = 'T';
 367     buf[1] = 'A';
 368     buf[2] = 'G';
 369     strncpy(buf + 3, s->title, 30);
 370     strncpy(buf + 33, s->author, 30);
 371     strncpy(buf + 63, s->album, 30);
 372     v = s->year;
 373     if (v > 0) {
 374         for(i = 0;i < 4; i++) {
 375             buf[96 - i] = '0' + (v % 10);
 376             v = v / 10;
 377         }
 378     }
 379     strncpy(buf + 97, s->comment, 30);
 380     if (s->track != 0) {
 381         buf[125] = 0;
 382         buf[126] = s->track;
 383     }
 384     for(i = 0; i <= ID3v1_GENRE_MAX; i++) {
 385         if (!strcasecmp(s->genre, id3v1_genre_str[i])) {
 386             buf[127] = i;
 387             break;
 388         }
 389     }
 390 }
 391
 392 /* mp3 read */
 393
 394 static int mp3_read_probe(AVProbeData *p)
 395 {
 396     int max_frames, first_frames = 0;
 397     int fsize, frames, sample_rate;
 398     uint32_t header;
 399     uint8_t *buf, *buf2, *end;
 400     AVCodecContext avctx;
 401
 402     if(id3v2_match(p->buf))
 403         return AVPROBE_SCORE_MAX/2+1; // this must be less than mpeg-ps because some retards put id3v2 tags before mpeg-ps files
 404
 405     max_frames = 0;
 406     buf = p->buf;
 407     end = buf + p->buf_size - sizeof(uint32_t);
 408
 409     for(; buf < end; buf= buf2+1) {
 410         buf2 = buf;
 411
 412         for(frames = 0; buf2 < end; frames++) {
 413             header = AV_RB32(buf2);
 414             fsize = ff_mpa_decode_header(&avctx, header, &sample_rate);
 415             if(fsize < 0)
 416                 break;
 417             buf2 += fsize;
 418         }
 419         max_frames = FFMAX(max_frames, frames);
 420         if(buf == p->buf)
 421             first_frames= frames;
 422     }
 423     if   (first_frames>=3) return AVPROBE_SCORE_MAX/2+1;
 424     else if(max_frames>500)return AVPROBE_SCORE_MAX/2;
 425     else if(max_frames>=3) return AVPROBE_SCORE_MAX/4;
 426     else if(max_frames>=1) return 1;
 427     else                   return 0;
 428 }
 429
 430 /**
 431  * Try to find Xing/Info/VBRI tags and compute duration from info therein
 432  */
 433 static void mp3_parse_vbr_tags(AVFormatContext *s, AVStream *st, offset_t base)
 434 {
 435     uint32_t v, spf;
 436     int frames = -1; /* Total number of frames in file */
 437     const offset_t xing_offtbl[2][2] = {{32, 17}, {17,9}};
 438     MPADecodeContext c;
 439
 440     v = get_be32(s->pb);
 441     if(ff_mpa_check_header(v) < 0)
 442       return;
 443
 444     ff_mpegaudio_decode_header(&c, v);
 445     if(c.layer != 3)
 446         return;
 447
 448     /* Check for Xing / Info tag */
 449     url_fseek(s->pb, xing_offtbl[c.lsf == 1][c.nb_channels == 1], SEEK_CUR);
 450     v = get_be32(s->pb);
 451     if(v == MKBETAG('X', 'i', 'n', 'g') || v == MKBETAG('I', 'n', 'f', 'o')) {
 452         v = get_be32(s->pb);
 453         if(v & 0x1)
 454             frames = get_be32(s->pb);
 455     }
 456
 457     /* Check for VBRI tag (always 32 bytes after end of mpegaudio header) */
 458     url_fseek(s->pb, base + 4 + 32, SEEK_SET);
 459     v = get_be32(s->pb);
 460     if(v == MKBETAG('V', 'B', 'R', 'I')) {
 461         /* Check tag version */
 462         if(get_be16(s->pb) == 1) {
 463             /* skip delay, quality and total bytes */
 464             url_fseek(s->pb, 8, SEEK_CUR);
 465             frames = get_be32(s->pb);
 466         }
 467     }
 468
 469     if(frames < 0)
 470         return;
 471
 472     spf = c.lsf ? 576 : 1152; /* Samples per frame, layer 3 */
 473     st->duration = av_rescale_q(frames, (AVRational){spf, c.sample_rate},
 474                                 st->time_base);
 475 }
 476
 477 static int mp3_read_header(AVFormatContext *s,
 478                            AVFormatParameters *ap)
 479 {
 480     AVStream *st;
 481     uint8_t buf[ID3v1_TAG_SIZE];
 482     int len, ret, filesize;
 483     offset_t off;
 484
 485     st = av_new_stream(s, 0);
 486     if (!st)
 487         return AVERROR(ENOMEM);
 488
 489     st->codec->codec_type = CODEC_TYPE_AUDIO;
 490     st->codec->codec_id = CODEC_ID_MP3;
 491     st->need_parsing = AVSTREAM_PARSE_FULL;
 492     st->start_time = 0;
 493
 494     /* try to get the TAG */
 495     if (!url_is_streamed(s->pb)) {
 496         /* XXX: change that */
 497         filesize = url_fsize(s->pb);
 498         if (filesize > 128) {
 499             url_fseek(s->pb, filesize - 128, SEEK_SET);
 500             ret = get_buffer(s->pb, buf, ID3v1_TAG_SIZE);
 501             if (ret == ID3v1_TAG_SIZE) {
 502                 id3v1_parse_tag(s, buf);
 503             }
 504             url_fseek(s->pb, 0, SEEK_SET);
 505         }
 506     }
 507
 508     /* if ID3v2 header found, skip it */
 509     ret = get_buffer(s->pb, buf, ID3v2_HEADER_SIZE);
 510     if (ret != ID3v2_HEADER_SIZE)
 511         return -1;
 512     if (id3v2_match(buf)) {
 513         /* parse ID3v2 header */
 514         len = ((buf[6] & 0x7f) << 21) |
 515             ((buf[7] & 0x7f) << 14) |
 516             ((buf[8] & 0x7f) << 7) |
 517             (buf[9] & 0x7f);
 518         id3v2_parse(s, len, buf[3], buf[5]);
 519     } else {
 520         url_fseek(s->pb, 0, SEEK_SET);
 521     }
 522
 523     off = url_ftell(s->pb);
 524     mp3_parse_vbr_tags(s, st, off);
 525     url_fseek(s->pb, off, SEEK_SET);
 526
 527     /* the parameters will be extracted from the compressed bitstream */
 528     return 0;
 529 }
 530
 531 #define MP3_PACKET_SIZE 1024
 532
 533 static int mp3_read_packet(AVFormatContext *s, AVPacket *pkt)
 534 {
 535     int ret, size;
 536     //    AVStream *st = s->streams[0];
 537
 538     size= MP3_PACKET_SIZE;
 539
 540     ret= av_get_packet(s->pb, pkt, size);
 541
 542     pkt->stream_index = 0;
 543     if (ret <= 0) {
 544         return AVERROR(EIO);
 545     }
 546     /* note: we need to modify the packet size here to handle the last
 547        packet */
 548     pkt->size = ret;
 549     return ret;
 550 }
 551
 552 static int mp3_read_close(AVFormatContext *s)
 553 {
 554     return 0;
 555 }
 556
 557 #ifdef CONFIG_MUXERS
 558 /* simple formats */
 559
 560 static void id3v2_put_size(AVFormatContext *s, int size)
 561 {
 562     put_byte(s->pb, size >> 21 & 0x7f);
 563     put_byte(s->pb, size >> 14 & 0x7f);
 564     put_byte(s->pb, size >> 7  & 0x7f);
 565     put_byte(s->pb, size       & 0x7f);
 566 }
 567
 568 static void id3v2_put_ttag(AVFormatContext *s, const char *string, uint32_t tag)
 569 {
 570     int len = strlen(string);
 571     put_be32(s->pb, tag);
 572     id3v2_put_size(s, len + 1);
 573     put_be16(s->pb, 0);
 574     put_byte(s->pb, 3); /* UTF-8 */
 575     put_buffer(s->pb, string, len);
 576 }
 577
 578
 579 /**
 580  * Write an ID3v2.4 header at beginning of stream
 581  */
 582
 583 static int mp3_write_header(struct AVFormatContext *s)
 584 {
 585     int totlen = 0;
 586     char tracktxt[10];
 587     char yeartxt[10];
 588
 589     if(s->track)
 590         snprintf(tracktxt, sizeof(tracktxt), "%d", s->track);
 591     if(s->year)
 592         snprintf( yeartxt, sizeof(yeartxt) , "%d", s->year );
 593
 594     if(s->title[0])     totlen += 11 + strlen(s->title);
 595     if(s->author[0])    totlen += 11 + strlen(s->author);
 596     if(s->album[0])     totlen += 11 + strlen(s->album);
 597     if(s->genre[0])     totlen += 11 + strlen(s->genre);
 598     if(s->copyright[0]) totlen += 11 + strlen(s->copyright);
 599     if(s->track)        totlen += 11 + strlen(tracktxt);
 600     if(s->year)         totlen += 11 + strlen(yeartxt);
 601     if(!(s->streams[0]->codec->flags & CODEC_FLAG_BITEXACT))
 602         totlen += strlen(LIBAVFORMAT_IDENT) + 11;
 603
 604     if(totlen == 0)
 605         return 0;
 606
 607     put_be32(s->pb, MKBETAG('I', 'D', '3', 0x04)); /* ID3v2.4 */
 608     put_byte(s->pb, 0);
 609     put_byte(s->pb, 0); /* flags */
 610
 611     id3v2_put_size(s, totlen);
 612
 613     if(s->title[0])     id3v2_put_ttag(s, s->title,     MKBETAG('T', 'I', 'T', '2'));
 614     if(s->author[0])    id3v2_put_ttag(s, s->author,    MKBETAG('T', 'P', 'E', '1'));
 615     if(s->album[0])     id3v2_put_ttag(s, s->album,     MKBETAG('T', 'A', 'L', 'B'));
 616     if(s->genre[0])     id3v2_put_ttag(s, s->genre,     MKBETAG('T', 'C', 'O', 'N'));
 617     if(s->copyright[0]) id3v2_put_ttag(s, s->copyright, MKBETAG('T', 'C', 'O', 'P'));
 618     if(s->track)        id3v2_put_ttag(s, tracktxt,     MKBETAG('T', 'R', 'C', 'K'));
 619     if(s->year)         id3v2_put_ttag(s, yeartxt,      MKBETAG('T', 'Y', 'E', 'R'));
 620     if(!(s->streams[0]->codec->flags & CODEC_FLAG_BITEXACT))
 621         id3v2_put_ttag(s, LIBAVFORMAT_IDENT,            MKBETAG('T', 'E', 'N', 'C'));
 622     return 0;
 623 }
 624
 625 static int mp3_write_packet(struct AVFormatContext *s, AVPacket *pkt)
 626 {
 627     put_buffer(s->pb, pkt->data, pkt->size);
 628     put_flush_packet(s->pb);
 629     return 0;
 630 }
 631
 632 static int mp3_write_trailer(struct AVFormatContext *s)
 633 {
 634     uint8_t buf[ID3v1_TAG_SIZE];
 635
 636     /* write the id3v1 tag */
 637     if (s->title[0] != '\0') {
 638         id3v1_create_tag(s, buf);
 639         put_buffer(s->pb, buf, ID3v1_TAG_SIZE);
 640         put_flush_packet(s->pb);
 641     }
 642     return 0;
 643 }
 644 #endif //CONFIG_MUXERS
 645
 646 #ifdef CONFIG_MP3_DEMUXER
 647 AVInputFormat mp3_demuxer = {
 648     "mp3",
 649     "MPEG audio",
 650     0,
 651     mp3_read_probe,
 652     mp3_read_header,
 653     mp3_read_packet,
 654     mp3_read_close,
 655     .flags= AVFMT_GENERIC_INDEX,
 656     .extensions = "mp2,mp3,m2a", /* XXX: use probe */
 657 };
 658 #endif
 659 #ifdef CONFIG_MP2_MUXER
 660 AVOutputFormat mp2_muxer = {
 661     "mp2",
 662     "MPEG audio layer 2",
 663     "audio/x-mpeg",
 664 #ifdef CONFIG_LIBMP3LAME
 665     "mp2,m2a",
 666 #else
 667     "mp2,mp3,m2a",
 668 #endif
 669     0,
 670     CODEC_ID_MP2,
 671     CODEC_ID_NONE,
 672     NULL,
 673     mp3_write_packet,
 674     mp3_write_trailer,
 675 };
 676 #endif
 677 #ifdef CONFIG_MP3_MUXER
 678 AVOutputFormat mp3_muxer = {
 679     "mp3",
 680     "MPEG audio layer 3",
 681     "audio/x-mpeg",
 682     "mp3",
 683     0,
 684     CODEC_ID_MP3,
 685     CODEC_ID_NONE,
 686     mp3_write_header,
 687     mp3_write_packet,
 688     mp3_write_trailer,
 689 };
 690 #endif