doxygen/6.1/id3v1_8c_source.html

/*

 * ID3v1 header parser

 * Copyright (c) 2003 Fabrice Bellard

 *

 * This file is part of FFmpeg.

 *

 * FFmpeg is free software; you can redistribute it and/or

 * modify it under the terms of the GNU Lesser General Public

 * License as published by the Free Software Foundation; either

 * version 2.1 of the License, or (at your option) any later version.

 *

 * FFmpeg is distributed in the hope that it will be useful,

 * but WITHOUT ANY WARRANTY; without even the implied warranty of

 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU

 * Lesser General Public License for more details.

 *

 * You should have received a copy of the GNU Lesser General Public

 * License along with FFmpeg; if not, write to the Free Software

 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA

 */


#include "id3v1.h"

#include "libavutil/dict.h"


/* See Genre List at http://id3.org/id3v2.3.0 */

const char * const ff_id3v1_genre_str[ID3v1_GENRE_MAX + 1] = {

      [0] = "Blues",

      [1] = "Classic Rock",

      [2] = "Country",

      [3] = "Dance",

      [4] = "Disco",

      [5] = "Funk",

      [6] = "Grunge",

      [7] = "Hip-Hop",

      [8] = "Jazz",

      [9] = "Metal",

     [10] = "New Age",

     [11] = "Oldies",

     [12] = "Other",

     [13] = "Pop",

     [14] = "R&B",

     [15] = "Rap",

     [16] = "Reggae",

     [17] = "Rock",

     [18] = "Techno",

     [19] = "Industrial",

     [20] = "Alternative",

     [21] = "Ska",

     [22] = "Death Metal",

     [23] = "Pranks",

     [24] = "Soundtrack",

     [25] = "Euro-Techno",

     [26] = "Ambient",

     [27] = "Trip-Hop",

     [28] = "Vocal",

     [29] = "Jazz+Funk",

     [30] = "Fusion",

     [31] = "Trance",

     [32] = "Classical",

     [33] = "Instrumental",

     [34] = "Acid",

     [35] = "House",

     [36] = "Game",

     [37] = "Sound Clip",

     [38] = "Gospel",

     [39] = "Noise",

     [40] = "AlternRock",

     [41] = "Bass",

     [42] = "Soul",

     [43] = "Punk",

     [44] = "Space",

     [45] = "Meditative",

     [46] = "Instrumental Pop",

     [47] = "Instrumental Rock",

     [48] = "Ethnic",

     [49] = "Gothic",

     [50] = "Darkwave",

     [51] = "Techno-Industrial",

     [52] = "Electronic",

     [53] = "Pop-Folk",

     [54] = "Eurodance",

     [55] = "Dream",

     [56] = "Southern Rock",

     [57] = "Comedy",

     [58] = "Cult",

     [59] = "Gangsta",

     [60] = "Top 40",

     [61] = "Christian Rap",

     [62] = "Pop/Funk",

     [63] = "Jungle",

     [64] = "Native American",

     [65] = "Cabaret",

     [66] = "New Wave",

     [67] = "Psychedelic",

     [68] = "Rave",

     [69] = "Showtunes",

     [70] = "Trailer",

     [71] = "Lo-Fi",

     [72] = "Tribal",

     [73] = "Acid Punk",

     [74] = "Acid Jazz",

     [75] = "Polka",

     [76] = "Retro",

     [77] = "Musical",

     [78] = "Rock & Roll",

     [79] = "Hard Rock",

     [80] = "Folk",

     [81] = "Folk-Rock",

     [82] = "National Folk",

     [83] = "Swing",

     [84] = "Fast Fusion",

     [85] = "Bebop",

     [86] = "Latin",

     [87] = "Revival",

     [88] = "Celtic",

     [89] = "Bluegrass",

     [90] = "Avantgarde",

     [91] = "Gothic Rock",

     [92] = "Progressive Rock",

     [93] = "Psychedelic Rock",

     [94] = "Symphonic Rock",

     [95] = "Slow Rock",

     [96] = "Big Band",

     [97] = "Chorus",

     [98] = "Easy Listening",

     [99] = "Acoustic",

    [100] = "Humour",

    [101] = "Speech",

    [102] = "Chanson",

    [103] = "Opera",

    [104] = "Chamber Music",

    [105] = "Sonata",

    [106] = "Symphony",

    [107] = "Booty Bass",

    [108] = "Primus",

    [109] = "Porn Groove",

    [110] = "Satire",

    [111] = "Slow Jam",

    [112] = "Club",

    [113] = "Tango",

    [114] = "Samba",

    [115] = "Folklore",

    [116] = "Ballad",

    [117] = "Power Ballad",

    [118] = "Rhythmic Soul",

    [119] = "Freestyle",

    [120] = "Duet",

    [121] = "Punk Rock",

    [122] = "Drum Solo",

    [123] = "A Cappella",

    [124] = "Euro-House",

    [125] = "Dance Hall",

    [126] = "Goa",

    [127] = "Drum & Bass",

    [128] = "Club-House",

    [129] = "Hardcore Techno",

    [130] = "Terror",

    [131] = "Indie",

    [132] = "BritPop",

    [133] = "Negerpunk",

    [134] = "Polsk Punk",

    [135] = "Beat",

    [136] = "Christian Gangsta Rap",

    [137] = "Heavy Metal",

    [138] = "Black Metal",

    [139] = "Crossover",

    [140] = "Contemporary Christian",

    [141] = "Christian Rock",

    [142] = "Merengue",

    [143] = "Salsa",

    [144] = "Thrash Metal",

    [145] = "Anime",

    [146] = "Jpop",

    [147] = "Synthpop",

    [148] = "Abstract",

    [149] = "Art Rock",

    [150] = "Baroque",

    [151] = "Bhangra",

    [152] = "Big Beat",

    [153] = "Breakbeat",

    [154] = "Chillout",

    [155] = "Downtempo",

    [156] = "Dub",

    [157] = "EBM",

    [158] = "Eclectic",

    [159] = "Electro",

    [160] = "Electroclash",

    [161] = "Emo",

    [162] = "Experimental",

    [163] = "Garage",

    [164] = "Global",

    [165] = "IDM",

    [166] = "Illbient",

    [167] = "Industro-Goth",

    [168] = "Jam Band",

    [169] = "Krautrock",

    [170] = "Leftfield",

    [171] = "Lounge",

    [172] = "Math Rock",

    [173] = "New Romantic",

    [174] = "Nu-Breakz",

    [175] = "Post-Punk",

    [176] = "Post-Rock",

    [177] = "Psytrance",

    [178] = "Shoegaze",

    [179] = "Space Rock",

    [180] = "Trop Rock",

    [181] = "World Music",

    [182] = "Neoclassical",

    [183] = "Audiobook",

    [184] = "Audio Theatre",

    [185] = "Neue Deutsche Welle",

    [186] = "Podcast",

    [187] = "Indie Rock",

    [188] = "G-Funk",

    [189] = "Dubstep",

    [190] = "Garage Rock",

    [191] = "Psybient"

};


static void get_string(AVFormatContext *s, const char *key,

                       const uint8_t *buf, int buf_size)

{

    int i, c;

    char *q, str[512], *first_free_space = NULL;


    q = str;

    for(i = 0; i < buf_size; i++) {

        c = buf[i];

        if (c == '\0')

            break;

        if ((q - str) >= sizeof(str) - 1)

            break;

        if (c == ' ') {

            if (!first_free_space)

                first_free_space = q;

        } else {

            first_free_space = NULL;

        }

        *q++ = c;

    }

    *q = '\0';


    if (first_free_space)

        *first_free_space = '\0';


    if (*str)

        av_dict_set(&s->metadata, key, str, 0);

}


/**

 * Parse an ID3v1 tag

 *

 * @param buf ID3v1_TAG_SIZE long buffer containing the tag

 */

static int parse_tag(AVFormatContext *s, const uint8_t *buf)

{

    int genre;


    if (!(buf[0] == 'T' &&

          buf[1] == 'A' &&

          buf[2] == 'G'))

        return -1;

    get_string(s, "title",   buf +  3, 30);

    get_string(s, "artist",  buf + 33, 30);

    get_string(s, "album",   buf + 63, 30);

    get_string(s, "date",    buf + 93,  4);

    get_string(s, "comment", buf + 97, 30);

    if (buf[125] == 0 && buf[126] != 0) {

        av_dict_set_int(&s->metadata, "track", buf[126], 0);

    }

    genre = buf[127];

    if (genre <= ID3v1_GENRE_MAX)

        av_dict_set(&s->metadata, "genre", ff_id3v1_genre_str[genre], 0);

    return 0;

}


void ff_id3v1_read(AVFormatContext *s)

{

    int ret;

    uint8_t buf[ID3v1_TAG_SIZE];

    int64_t filesize, position = avio_tell(s->pb);


    if (s->pb->seekable & AVIO_SEEKABLE_NORMAL) {

        /* XXX: change that */

        filesize = avio_size(s->pb);

        if (filesize > 128) {

            avio_seek(s->pb, filesize - 128, SEEK_SET);

            ret = avio_read(s->pb, buf, ID3v1_TAG_SIZE);

            if (ret == ID3v1_TAG_SIZE) {

                parse_tag(s, buf);

            }

            avio_seek(s->pb, position, SEEK_SET);

        }

    }

}