/*  * MP3 encoder and decoder * Copyright (c) 2003 Fabrice Bellard. * * This library 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 of the License, or (at your option) any later version. * * This library 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 this library; if not, write to the Free Software * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA */#include "avformat.h"#define ID3_HEADER_SIZE 10#define ID3_TAG_SIZE 128#define ID3_GENRE_MAX 125static const char *id3_genre_str[ID3_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] = "Psychadelic",    [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] = "Bebob",    [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 capella",    [124] = "Euro-House",    [125] = "Dance Hall",};/* buf must be ID3_HEADER_SIZE byte long */static int id3_match(const uint8_t *buf){    return (buf[0] == 'I' &&            buf[1] == 'D' &&            buf[2] == '3' &&            buf[3] != 0xff &&            buf[4] != 0xff &&            (buf[6] & 0x80) == 0 &&            (buf[7] & 0x80) == 0 &&            (buf[8] & 0x80) == 0 &&            (buf[9] & 0x80) == 0);}static void id3_get_string(char *str, int str_size,                            const uint8_t *buf, int buf_size){    int i, c;    char *q;    q = str;    for(i = 0; i < buf_size; i++) {        c = buf[i];        if (c == '\0')            break;        if ((q - str) >= str_size - 1)            break;        *q++ = c;    }    *q = '\0';}/* 'buf' must be ID3_TAG_SIZE byte long */static int id3_parse_tag(AVFormatContext *s, const uint8_t *buf){    char str[5];    int genre;        if (!(buf[0] == 'T' &&          buf[1] == 'A' &&          buf[2] == 'G'))        return -1;    id3_get_string(s->title, sizeof(s->title), buf + 3, 30);    id3_get_string(s->author, sizeof(s->author), buf + 33, 30);    id3_get_string(s->album, sizeof(s->album), buf + 63, 30);    id3_get_string(str, sizeof(str), buf + 93, 4);    s->year = atoi(str);    id3_get_string(s->comment, sizeof(s->comment), buf + 97, 30);    if (buf[125] == 0 && buf[126] != 0)        s->track = buf[126];    genre = buf[127];    if (genre <= ID3_GENRE_MAX)        pstrcpy(s->genre, sizeof(s->genre), id3_genre_str[genre]);    return 0;}static void id3_create_tag(AVFormatContext *s, uint8_t *buf){    int v, i;    memset(buf, 0, ID3_TAG_SIZE); /* fail safe */    buf[0] = 'T';    buf[1] = 'A';    buf[2] = 'G';    strncpy(buf + 3, s->title, 30);    strncpy(buf + 33, s->author, 30);    strncpy(buf + 63, s->album, 30);    v = s->year;    if (v > 0) {        for(i = 0;i < 4; i++) {            buf[96 - i] = '0' + (v % 10);            v = v / 10;        }    }    strncpy(buf + 97, s->comment, 30);    if (s->track != 0) {        buf[125] = 0;        buf[126] = s->track;    }    for(i = 0; i <= ID3_GENRE_MAX; i++) {        if (!strcasecmp(s->genre, id3_genre_str[i])) {            buf[127] = i;            break;        }    }}/* mp3 read */static int mp3_read_header(AVFormatContext *s,                           AVFormatParameters *ap){    AVStream *st;    uint8_t buf[ID3_TAG_SIZE];    int len, ret, filesize;    st = av_new_stream(s, 0);    if (!st)        return AVERROR_NOMEM;    st->codec.codec_type = CODEC_TYPE_AUDIO;    st->codec.codec_id = CODEC_ID_MP3;    st->need_parsing = 1;        /* try to get the TAG */    if (!url_is_streamed(&s->pb)) {        /* XXX: change that */        filesize = url_filesize(url_fileno(&s->pb));        if (filesize > 128) {            url_fseek(&s->pb, filesize - 128, SEEK_SET);            ret = get_buffer(&s->pb, buf, ID3_TAG_SIZE);            if (ret == ID3_TAG_SIZE) {                id3_parse_tag(s, buf);            }            url_fseek(&s->pb, 0, SEEK_SET);        }    }    /* if ID3 header found, skip it */    ret = get_buffer(&s->pb, buf, ID3_HEADER_SIZE);    if (ret != ID3_HEADER_SIZE)        return -1;    if (id3_match(buf)) {        /* skip ID3 header */        len = ((buf[6] & 0x7f) << 21) |            ((buf[7] & 0x7f) << 14) |            ((buf[8] & 0x7f) << 7) |            (buf[9] & 0x7f);        url_fskip(&s->pb, len);    } else {        url_fseek(&s->pb, 0, SEEK_SET);    }    /* the parameters will be extracted from the compressed bitstream */    return 0;}#define MP3_PACKET_SIZE 1024static int mp3_read_packet(AVFormatContext *s, AVPacket *pkt){    int ret, size;    //    AVStream *st = s->streams[0];        size= MP3_PACKET_SIZE;    if (av_new_packet(pkt, size) < 0)        return AVERROR_IO;    pkt->stream_index = 0;    ret = get_buffer(&s->pb, pkt->data, size);    if (ret <= 0) {        av_free_packet(pkt);        return AVERROR_IO;    }    /* note: we need to modify the packet size here to handle the last       packet */    pkt->size = ret;    return ret;}static int mp3_read_close(AVFormatContext *s){    return 0;}#ifdef CONFIG_ENCODERS/* simple formats */static int mp3_write_header(struct AVFormatContext *s){    return 0;}static int mp3_write_packet(struct AVFormatContext *s, AVPacket *pkt){    put_buffer(&s->pb, pkt->data, pkt->size);    put_flush_packet(&s->pb);    return 0;}static int mp3_write_trailer(struct AVFormatContext *s){    uint8_t buf[ID3_TAG_SIZE];    /* write the id3 header */    if (s->title[0] != '\0') {        id3_create_tag(s, buf);        put_buffer(&s->pb, buf, ID3_TAG_SIZE);        put_flush_packet(&s->pb);    }    return 0;}#endif //CONFIG_ENCODERSAVInputFormat mp3_iformat = {    "mp3",    "MPEG audio",    0,    NULL,    mp3_read_header,    mp3_read_packet,    mp3_read_close,    .extensions = "mp2,mp3", /* XXX: use probe */};#ifdef CONFIG_ENCODERSAVOutputFormat mp2_oformat = {    "mp2",    "MPEG audio layer 2",    "audio/x-mpeg",#ifdef CONFIG_MP3LAME    "mp2",#else    "mp2,mp3",#endif    0,    CODEC_ID_MP2,    0,    mp3_write_header,    mp3_write_packet,    mp3_write_trailer,};#ifdef CONFIG_MP3LAMEAVOutputFormat mp3_oformat = {    "mp3",    "MPEG audio layer 3",    "audio/x-mpeg",    "mp3",    0,    CODEC_ID_MP3,    0,    mp3_write_header,    mp3_write_packet,    mp3_write_trailer,};#endif#endif //CONFIG_ENCODERSint mp3_init(void){    av_register_input_format(&mp3_iformat);#ifdef CONFIG_ENCODERS    av_register_output_format(&mp2_oformat);#ifdef CONFIG_MP3LAME    av_register_output_format(&mp3_oformat);#endif    #endif //CONFIG_ENCODERS    return 0;}