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/*
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 * MP3 encoder and decoder
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 * Copyright (c) 2003 Fabrice Bellard.
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 *
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 * This library is free software; you can redistribute it and/or
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 * modify it under the terms of the GNU Lesser General Public
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 * License as published by the Free Software Foundation; either
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 * version 2 of the License, or (at your option) any later version.
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 *
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 * This library is distributed in the hope that it will be useful,
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 * but WITHOUT ANY WARRANTY; without even the implied warranty of
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 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
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 * Lesser General Public License for more details.
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 *
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 * You should have received a copy of the GNU Lesser General Public
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 * License along with this library; if not, write to the Free Software
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 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
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 */
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#include "avformat.h"
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#define ID3_HEADER_SIZE 10
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#define ID3_TAG_SIZE 128
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#define ID3_GENRE_MAX 125
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static const char *id3_genre_str[ID3_GENRE_MAX + 1] = {
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    [0] = "Blues",
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    [1] = "Classic Rock",
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    [2] = "Country",
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    [3] = "Dance",
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    [4] = "Disco",
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    [5] = "Funk",
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    [6] = "Grunge",
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    [7] = "Hip-Hop",
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    [8] = "Jazz",
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    [9] = "Metal",
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    [10] = "New Age",
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    [11] = "Oldies",
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    [12] = "Other",
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    [13] = "Pop",
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    [14] = "R&B",
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    [15] = "Rap",
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    [16] = "Reggae",
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    [17] = "Rock",
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    [18] = "Techno",
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    [19] = "Industrial",
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    [20] = "Alternative",
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    [21] = "Ska",
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    [22] = "Death Metal",
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    [23] = "Pranks",
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    [24] = "Soundtrack",
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    [25] = "Euro-Techno",
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    [26] = "Ambient",
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    [27] = "Trip-Hop",
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    [28] = "Vocal",
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    [29] = "Jazz+Funk",
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    [30] = "Fusion",
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    [31] = "Trance",
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    [32] = "Classical",
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    [33] = "Instrumental",
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    [34] = "Acid",
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    [35] = "House",
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    [36] = "Game",
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    [37] = "Sound Clip",
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    [38] = "Gospel",
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    [39] = "Noise",
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    [40] = "AlternRock",
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    [41] = "Bass",
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    [42] = "Soul",
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    [43] = "Punk",
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    [44] = "Space",
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    [45] = "Meditative",
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    [46] = "Instrumental Pop",
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    [47] = "Instrumental Rock",
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    [48] = "Ethnic",
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    [49] = "Gothic",
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    [50] = "Darkwave",
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    [51] = "Techno-Industrial",
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    [52] = "Electronic",
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    [53] = "Pop-Folk",
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    [54] = "Eurodance",
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    [55] = "Dream",
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    [56] = "Southern Rock",
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    [57] = "Comedy",
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    [58] = "Cult",
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    [59] = "Gangsta",
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    [60] = "Top 40",
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    [61] = "Christian Rap",
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    [62] = "Pop/Funk",
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    [63] = "Jungle",
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    [64] = "Native American",
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    [65] = "Cabaret",
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    [66] = "New Wave",
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    [67] = "Psychadelic",
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    [68] = "Rave",
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    [69] = "Showtunes",
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    [70] = "Trailer",
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    [71] = "Lo-Fi",
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    [72] = "Tribal",
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    [73] = "Acid Punk",
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    [74] = "Acid Jazz",
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    [75] = "Polka",
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    [76] = "Retro",
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    [77] = "Musical",
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    [78] = "Rock & Roll",
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    [79] = "Hard Rock",
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    [80] = "Folk",
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    [81] = "Folk-Rock",
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    [82] = "National Folk",
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    [83] = "Swing",
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    [84] = "Fast Fusion",
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    [85] = "Bebob",
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    [86] = "Latin",
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    [87] = "Revival",
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    [88] = "Celtic",
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    [89] = "Bluegrass",
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    [90] = "Avantgarde",
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    [91] = "Gothic Rock",
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    [92] = "Progressive Rock",
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    [93] = "Psychedelic Rock",
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    [94] = "Symphonic Rock",
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    [95] = "Slow Rock",
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    [96] = "Big Band",
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    [97] = "Chorus",
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    [98] = "Easy Listening",
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    [99] = "Acoustic",
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    [100] = "Humour",
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    [101] = "Speech",
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    [102] = "Chanson",
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    [103] = "Opera",
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    [104] = "Chamber Music",
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    [105] = "Sonata",
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    [106] = "Symphony",
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    [107] = "Booty Bass",
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    [108] = "Primus",
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    [109] = "Porn Groove",
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    [110] = "Satire",
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    [111] = "Slow Jam",
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    [112] = "Club",
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    [113] = "Tango",
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    [114] = "Samba",
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    [115] = "Folklore",
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    [116] = "Ballad",
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    [117] = "Power Ballad",
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    [118] = "Rhythmic Soul",
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    [119] = "Freestyle",
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    [120] = "Duet",
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    [121] = "Punk Rock",
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    [122] = "Drum Solo",
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    [123] = "A capella",
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    [124] = "Euro-House",
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    [125] = "Dance Hall",
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};
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/* buf must be ID3_HEADER_SIZE byte long */
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static int id3_match(const uint8_t *buf)
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{
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    return (buf[0] == 'I' &&
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            buf[1] == 'D' &&
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            buf[2] == '3' &&
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            buf[3] != 0xff &&
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            buf[4] != 0xff &&
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            (buf[6] & 0x80) == 0 &&
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            (buf[7] & 0x80) == 0 &&
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            (buf[8] & 0x80) == 0 &&
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            (buf[9] & 0x80) == 0);
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}
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static void id3_get_string(char *str, int str_size,
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                           const uint8_t *buf, int buf_size)
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{
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    int i, c;
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    char *q;
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    q = str;
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    for(i = 0; i < buf_size; i++) {
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        c = buf[i];
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        if (c == '\0')
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            break;
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        if ((q - str) >= str_size - 1)
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            break;
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        *q++ = c;
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    }
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    *q = '\0';
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}
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/* 'buf' must be ID3_TAG_SIZE byte long */
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static int id3_parse_tag(AVFormatContext *s, const uint8_t *buf)
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{
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    char str[5];
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    int genre;
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    if (!(buf[0] == 'T' &&
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          buf[1] == 'A' &&
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          buf[2] == 'G'))
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        return -1;
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    id3_get_string(s->title, sizeof(s->title), buf + 3, 30);
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    id3_get_string(s->author, sizeof(s->author), buf + 33, 30);
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    id3_get_string(s->album, sizeof(s->album), buf + 63, 30);
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    id3_get_string(str, sizeof(str), buf + 93, 4);
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    s->year = atoi(str);
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    id3_get_string(s->comment, sizeof(s->comment), buf + 97, 30);
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    if (buf[125] == 0 && buf[126] != 0)
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        s->track = buf[126];
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    genre = buf[127];
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    if (genre <= ID3_GENRE_MAX)
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        pstrcpy(s->genre, sizeof(s->genre), id3_genre_str[genre]);
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    return 0;
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}
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static void id3_create_tag(AVFormatContext *s, uint8_t *buf)
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{
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    int v, i;
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    memset(buf, 0, ID3_TAG_SIZE); /* fail safe */
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    buf[0] = 'T';
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    buf[1] = 'A';
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    buf[2] = 'G';
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    strncpy(buf + 3, s->title, 30);
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    strncpy(buf + 33, s->author, 30);
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    strncpy(buf + 63, s->album, 30);
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    v = s->year;
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    if (v > 0) {
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        for(i = 0;i < 4; i++) {
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            buf[96 - i] = '0' + (v % 10);
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            v = v / 10;
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        }
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    }
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    strncpy(buf + 97, s->comment, 30);
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    if (s->track != 0) {
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        buf[125] = 0;
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        buf[126] = s->track;
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    }
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    for(i = 0; i <= ID3_GENRE_MAX; i++) {
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        if (!strcasecmp(s->genre, id3_genre_str[i])) {
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            buf[127] = i;
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            break;
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        }
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    }
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}
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/* mp3 read */
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static int mp3_read_probe(AVProbeData *p)
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{
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    int d;
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    if(p->buf_size < 4)
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        return 0;
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    if(p->buf[0] == 'I' && p->buf[1] == 'D' && p->buf[2] == '3' &&
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       p->buf[3] < 5)
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        return AVPROBE_SCORE_MAX;
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    if(p->buf[0] != 0xff)
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        return 0;
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    d = p->buf[1];
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    if((d & 0xe0) != 0xe0 || ((d & 0x18) == 0x08 || (d & 0x06) == 0))
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        return 0;
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    d = p->buf[2];
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    if((d & 0xf0) == 0xf0 || (d & 0x0c) == 0x0c)
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        return 0;
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    return AVPROBE_SCORE_MAX;
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}
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static int mp3_read_header(AVFormatContext *s,
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                           AVFormatParameters *ap)
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{
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    AVStream *st;
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    uint8_t buf[ID3_TAG_SIZE];
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    int len, ret, filesize;
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    st = av_new_stream(s, 0);
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    if (!st)
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        return AVERROR_NOMEM;
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    st->codec->codec_type = CODEC_TYPE_AUDIO;
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    st->codec->codec_id = CODEC_ID_MP3;
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    st->need_parsing = 1;
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    /* try to get the TAG */
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    if (!url_is_streamed(&s->pb)) {
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        /* XXX: change that */
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        filesize = url_fsize(&s->pb);
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        if (filesize > 128) {
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            url_fseek(&s->pb, filesize - 128, SEEK_SET);
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            ret = get_buffer(&s->pb, buf, ID3_TAG_SIZE);
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            if (ret == ID3_TAG_SIZE) {
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                id3_parse_tag(s, buf);
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            }
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            url_fseek(&s->pb, 0, SEEK_SET);
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        }
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    }
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    /* if ID3 header found, skip it */
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    ret = get_buffer(&s->pb, buf, ID3_HEADER_SIZE);
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    if (ret != ID3_HEADER_SIZE)
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        return -1;
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    if (id3_match(buf)) {
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        /* skip ID3 header */
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        len = ((buf[6] & 0x7f) << 21) |
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            ((buf[7] & 0x7f) << 14) |
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            ((buf[8] & 0x7f) << 7) |
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            (buf[9] & 0x7f);
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        url_fskip(&s->pb, len);
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    } else {
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        url_fseek(&s->pb, 0, SEEK_SET);
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    }
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    /* the parameters will be extracted from the compressed bitstream */
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    return 0;
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}
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#define MP3_PACKET_SIZE 1024
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static int mp3_read_packet(AVFormatContext *s, AVPacket *pkt)
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{
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    int ret, size;
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    //    AVStream *st = s->streams[0];
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    size= MP3_PACKET_SIZE;
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    ret= av_get_packet(&s->pb, pkt, size);
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    pkt->stream_index = 0;
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    if (ret <= 0) {
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        return AVERROR_IO;
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    }
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    /* note: we need to modify the packet size here to handle the last
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       packet */
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    pkt->size = ret;
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    return ret;
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}
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static int mp3_read_close(AVFormatContext *s)
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{
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    return 0;
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}
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#ifdef CONFIG_MUXERS
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/* simple formats */
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static int mp3_write_header(struct AVFormatContext *s)
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{
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    return 0;
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}
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static int mp3_write_packet(struct AVFormatContext *s, AVPacket *pkt)
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{
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    put_buffer(&s->pb, pkt->data, pkt->size);
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    put_flush_packet(&s->pb);
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    return 0;
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}
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static int mp3_write_trailer(struct AVFormatContext *s)
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{
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    uint8_t buf[ID3_TAG_SIZE];
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    /* write the id3 header */
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    if (s->title[0] != '\0') {
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        id3_create_tag(s, buf);
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        put_buffer(&s->pb, buf, ID3_TAG_SIZE);
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        put_flush_packet(&s->pb);
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    }
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    return 0;
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}
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#endif //CONFIG_MUXERS
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AVInputFormat mp3_iformat = {
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    "mp3",
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    "MPEG audio",
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    0,
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    mp3_read_probe,
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    mp3_read_header,
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    mp3_read_packet,
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    mp3_read_close,
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    .extensions = "mp2,mp3,m2a", /* XXX: use probe */
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};
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#ifdef CONFIG_MUXERS
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AVOutputFormat mp2_oformat = {
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    "mp2",
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    "MPEG audio layer 2",
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    "audio/x-mpeg",
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#ifdef CONFIG_MP3LAME
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    "mp2,m2a",
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#else
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    "mp2,mp3,m2a",
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#endif
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    0,
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    CODEC_ID_MP2,
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    0,
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    mp3_write_header,
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    mp3_write_packet,
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    mp3_write_trailer,
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};
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#ifdef CONFIG_MP3LAME
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AVOutputFormat mp3_oformat = {
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    "mp3",
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    "MPEG audio layer 3",
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    "audio/x-mpeg",
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    "mp3",
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    0,
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    CODEC_ID_MP3,
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    0,
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    mp3_write_header,
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    mp3_write_packet,
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    mp3_write_trailer,
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};
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#endif
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#endif //CONFIG_MUXERS
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int mp3_init(void)
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{
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    av_register_input_format(&mp3_iformat);
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#ifdef CONFIG_MUXERS
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    av_register_output_format(&mp2_oformat);
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#ifdef CONFIG_MP3LAME
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    av_register_output_format(&mp3_oformat);
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#endif
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#endif //CONFIG_MUXERS
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    return 0;
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}