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ffmpeg / libavformat / mp3.c @ 9c5a9e6b

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1 115329f1 Diego Biurrun
/*
2 7fbde343 Aurelien Jacobs
 * MP3 muxer and demuxer
3 406792e7 Diego Biurrun
 * Copyright (c) 2003 Fabrice Bellard
4 6a58e151 Fabrice Bellard
 *
5 b78e7197 Diego Biurrun
 * This file is part of FFmpeg.
6
 *
7
 * FFmpeg is free software; you can redistribute it and/or
8 6a58e151 Fabrice Bellard
 * modify it under the terms of the GNU Lesser General Public
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 * License as published by the Free Software Foundation; either
10 b78e7197 Diego Biurrun
 * version 2.1 of the License, or (at your option) any later version.
11 6a58e151 Fabrice Bellard
 *
12 b78e7197 Diego Biurrun
 * FFmpeg is distributed in the hope that it will be useful,
13 6a58e151 Fabrice Bellard
 * 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 b78e7197 Diego Biurrun
 * License along with FFmpeg; if not, write to the Free Software
19 5509bffa Diego Biurrun
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20 6a58e151 Fabrice Bellard
 */
21 245976da Diego Biurrun
22 ea452b54 Aurelien Jacobs
#include <strings.h>
23 245976da Diego Biurrun
#include "libavutil/avstring.h"
24 ff06d76a Diego Biurrun
#include "libavutil/intreadwrite.h"
25 6a58e151 Fabrice Bellard
#include "avformat.h"
26 2ea512a6 Alex Converse
#include "id3v2.h"
27 75411182 Patrick Dehne
#include "id3v1.h"
28 52b53f86 Andreas Öman
29 de653ba3 Diego Biurrun
#if CONFIG_MP3_DEMUXER
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31
#include "libavcodec/mpegaudio.h"
32
#include "libavcodec/mpegaudiodecheader.h"
33
34 6a58e151 Fabrice Bellard
/* mp3 read */
35 dc4ed3b1 Måns Rullgård
36
static int mp3_read_probe(AVProbeData *p)
37
{
38 ea7599ba Måns Rullgård
    int max_frames, first_frames = 0;
39 498c544a Michael Niedermayer
    int fsize, frames, sample_rate;
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    uint32_t header;
41 ac3ef4a4 Alex Converse
    uint8_t *buf, *buf0, *buf2, *end;
42 abade142 Andreas Öman
    AVCodecContext avctx;
43 dc4ed3b1 Måns Rullgård
44 ac3ef4a4 Alex Converse
    buf0 = p->buf;
45
    if(ff_id3v2_match(buf0)) {
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        buf0 += ff_id3v2_tag_len(buf0);
47
    }
48 dc4ed3b1 Måns Rullgård
49 abade142 Andreas Öman
    max_frames = 0;
50 ac3ef4a4 Alex Converse
    buf = buf0;
51 38cef584 Alex Converse
    end = p->buf + p->buf_size - sizeof(uint32_t);
52 dc4ed3b1 Måns Rullgård
53 5ef5501b Michael Niedermayer
    for(; buf < end; buf= buf2+1) {
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        buf2 = buf;
55 dc4ed3b1 Måns Rullgård
56 d0702de9 Michael Niedermayer
        for(frames = 0; buf2 < end; frames++) {
57 80fb8234 Ronald S. Bultje
            header = AV_RB32(buf2);
58 c96bd212 Michael Niedermayer
            fsize = ff_mpa_decode_header(&avctx, header, &sample_rate, &sample_rate, &sample_rate, &sample_rate);
59 abade142 Andreas Öman
            if(fsize < 0)
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                break;
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            buf2 += fsize;
62
        }
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        max_frames = FFMAX(max_frames, frames);
64 ac3ef4a4 Alex Converse
        if(buf == buf0)
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            first_frames= frames;
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    }
67 4b4ac5c7 Reimar Döffinger
    // keep this in sync with ac3 probe, both need to avoid
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    // issues with MPEG-files!
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    if   (first_frames>=4) return AVPROBE_SCORE_MAX/2+1;
70 2db97113 Michael Niedermayer
    else if(max_frames>500)return AVPROBE_SCORE_MAX/2;
71 f9f2ab82 Michael Niedermayer
    else if(max_frames>=4) return AVPROBE_SCORE_MAX/4;
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    else if(buf0!=p->buf)  return AVPROBE_SCORE_MAX/4-1;
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    else if(max_frames>=1) return 1;
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    else                   return 0;
75 f9f2ab82 Michael Niedermayer
//mpegps_mp3_unrecognized_format.mpg has max_frames=3
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}
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/**
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 * Try to find Xing/Info/VBRI tags and compute duration from info therein
80 ca851a3a Andreas Öman
 */
81 853a9753 Yoav Steinberg
static int mp3_parse_vbr_tags(AVFormatContext *s, AVStream *st, int64_t base)
82 ca851a3a Andreas Öman
{
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    uint32_t v, spf;
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    int frames = -1; /* Total number of frames in file */
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    const int64_t xing_offtbl[2][2] = {{32, 17}, {17,9}};
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    MPADecodeHeader c;
87 853a9753 Yoav Steinberg
    int vbrtag_size = 0;
88 ca851a3a Andreas Öman
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    v = get_be32(s->pb);
90 5b5bd7c9 Andreas Öman
    if(ff_mpa_check_header(v) < 0)
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      return -1;
92 5b5bd7c9 Andreas Öman
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    if (ff_mpegaudio_decode_header(&c, v) == 0)
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        vbrtag_size = c.frame_size;
95 db233e83 Andreas Öman
    if(c.layer != 3)
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        return -1;
97 ca851a3a Andreas Öman
98 db233e83 Andreas Öman
    /* Check for Xing / Info tag */
99 899681cd Björn Axelsson
    url_fseek(s->pb, xing_offtbl[c.lsf == 1][c.nb_channels == 1], SEEK_CUR);
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    v = get_be32(s->pb);
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    if(v == MKBETAG('X', 'i', 'n', 'g') || v == MKBETAG('I', 'n', 'f', 'o')) {
102 899681cd Björn Axelsson
        v = get_be32(s->pb);
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        if(v & 0x1)
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            frames = get_be32(s->pb);
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    }
106 db233e83 Andreas Öman
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    /* Check for VBRI tag (always 32 bytes after end of mpegaudio header) */
108 899681cd Björn Axelsson
    url_fseek(s->pb, base + 4 + 32, SEEK_SET);
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    v = get_be32(s->pb);
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    if(v == MKBETAG('V', 'B', 'R', 'I')) {
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        /* Check tag version */
112 899681cd Björn Axelsson
        if(get_be16(s->pb) == 1) {
113 8862fb41 Andreas Öman
            /* skip delay, quality and total bytes */
114 899681cd Björn Axelsson
            url_fseek(s->pb, 8, SEEK_CUR);
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            frames = get_be32(s->pb);
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        }
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    }
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119 db233e83 Andreas Öman
    if(frames < 0)
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        return -1;
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    /* Skip the vbr tag frame */
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    url_fseek(s->pb, base + vbrtag_size, SEEK_SET);
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    spf = c.lsf ? 576 : 1152; /* Samples per frame, layer 3 */
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    st->duration = av_rescale_q(frames, (AVRational){spf, c.sample_rate},
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                                st->time_base);
128 853a9753 Yoav Steinberg
    return 0;
129 ca851a3a Andreas Öman
}
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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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    int64_t off;
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    st = av_new_stream(s, 0);
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    if (!st)
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        return AVERROR(ENOMEM);
140 6a58e151 Fabrice Bellard
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    st->codec->codec_type = CODEC_TYPE_AUDIO;
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    st->codec->codec_id = CODEC_ID_MP3;
143 57004ff1 Aurelien Jacobs
    st->need_parsing = AVSTREAM_PARSE_FULL;
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    st->start_time = 0;
145 115329f1 Diego Biurrun
146 9c5a9e6b Baptiste Coudurier
    // lcm of all mp3 sample rates
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    av_set_pts_info(st, 64, 1, 14112000);
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149 50fcd5be Patrick Dehne
    ff_id3v2_read(s);
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    if (!av_metadata_get(s->metadata, "", NULL, AV_METADATA_IGNORE_SUFFIX))
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        ff_id3v1_read(s);
152 6a58e151 Fabrice Bellard
153 899681cd Björn Axelsson
    off = url_ftell(s->pb);
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    if (mp3_parse_vbr_tags(s, st, off) < 0)
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        url_fseek(s->pb, off, SEEK_SET);
156 ca851a3a Andreas Öman
157 6a58e151 Fabrice Bellard
    /* the parameters will be extracted from the compressed bitstream */
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    return 0;
159
}
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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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168 6a58e151 Fabrice Bellard
    size= MP3_PACKET_SIZE;
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170 899681cd Björn Axelsson
    ret= av_get_packet(s->pb, pkt, size);
171 6a58e151 Fabrice Bellard
172
    pkt->stream_index = 0;
173
    if (ret <= 0) {
174 6f3e0b21 Panagiotis Issaris
        return AVERROR(EIO);
175 6a58e151 Fabrice Bellard
    }
176
    /* 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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182 de653ba3 Diego Biurrun
AVInputFormat mp3_demuxer = {
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    "mp3",
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    NULL_IF_CONFIG_SMALL("MPEG audio layer 2/3"),
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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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    .flags= AVFMT_GENERIC_INDEX,
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    .extensions = "mp2,mp3,m2a", /* XXX: use probe */
191 41770abf Anton Khirnov
    .metadata_conv = ff_id3v2_metadata_conv,
192 de653ba3 Diego Biurrun
};
193
#endif
194
195 b250f9c6 Aurelien Jacobs
#if CONFIG_MP2_MUXER || CONFIG_MP3_MUXER
196 b182eeb0 Aurelien Jacobs
static int id3v1_set_string(AVFormatContext *s, const char *key,
197
                            uint8_t *buf, int buf_size)
198 58607ca7 Diego Biurrun
{
199 b182eeb0 Aurelien Jacobs
    AVMetadataTag *tag;
200
    if ((tag = av_metadata_get(s->metadata, key, NULL, 0)))
201
        strncpy(buf, tag->value, buf_size);
202
    return !!tag;
203
}
204
205
static int id3v1_create_tag(AVFormatContext *s, uint8_t *buf)
206
{
207
    AVMetadataTag *tag;
208
    int i, count = 0;
209 58607ca7 Diego Biurrun
210
    memset(buf, 0, ID3v1_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';
214 b182eeb0 Aurelien Jacobs
    count += id3v1_set_string(s, "title",   buf +  3, 30);
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    count += id3v1_set_string(s, "author",  buf + 33, 30);
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    count += id3v1_set_string(s, "album",   buf + 63, 30);
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    count += id3v1_set_string(s, "year",    buf + 93,  4);
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    count += id3v1_set_string(s, "comment", buf + 97, 30);
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    if ((tag = av_metadata_get(s->metadata, "track", NULL, 0))) {
220 58607ca7 Diego Biurrun
        buf[125] = 0;
221 b182eeb0 Aurelien Jacobs
        buf[126] = atoi(tag->value);
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        count++;
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    }
224 ea25c063 Justin Ruggles
    buf[127] = 0xFF; /* default to unknown genre */
225 b182eeb0 Aurelien Jacobs
    if ((tag = av_metadata_get(s->metadata, "genre", NULL, 0))) {
226 ee56cab3 Aurelien Jacobs
        for(i = 0; i <= ID3v1_GENRE_MAX; i++) {
227 75411182 Patrick Dehne
            if (!strcasecmp(tag->value, ff_id3v1_genre_str[i])) {
228 ee56cab3 Aurelien Jacobs
                buf[127] = i;
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                count++;
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                break;
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            }
232 58607ca7 Diego Biurrun
        }
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    }
234 b182eeb0 Aurelien Jacobs
    return count;
235 58607ca7 Diego Biurrun
}
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237 6a58e151 Fabrice Bellard
/* simple formats */
238 0dc56bfa Andreas Öman
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static void id3v2_put_size(AVFormatContext *s, int size)
240
{
241 899681cd Björn Axelsson
    put_byte(s->pb, size >> 21 & 0x7f);
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    put_byte(s->pb, size >> 14 & 0x7f);
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    put_byte(s->pb, size >> 7  & 0x7f);
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    put_byte(s->pb, size       & 0x7f);
245 0dc56bfa Andreas Öman
}
246
247 078d89a2 Anton Khirnov
static void id3v2_put_ttag(AVFormatContext *s, const char *buf, int len,
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                           uint32_t tag)
249 0dc56bfa Andreas Öman
{
250 899681cd Björn Axelsson
    put_be32(s->pb, tag);
251 0dc56bfa Andreas Öman
    id3v2_put_size(s, len + 1);
252 899681cd Björn Axelsson
    put_be16(s->pb, 0);
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    put_byte(s->pb, 3); /* UTF-8 */
254 078d89a2 Anton Khirnov
    put_buffer(s->pb, buf, len);
255 0dc56bfa Andreas Öman
}
256
257
258 0cd0a224 Diego Biurrun
static int mp3_write_packet(struct AVFormatContext *s, AVPacket *pkt)
259
{
260
    put_buffer(s->pb, pkt->data, pkt->size);
261
    put_flush_packet(s->pb);
262
    return 0;
263
}
264
265
static int mp3_write_trailer(struct AVFormatContext *s)
266
{
267
    uint8_t buf[ID3v1_TAG_SIZE];
268
269
    /* write the id3v1 tag */
270
    if (id3v1_create_tag(s, buf) > 0) {
271
        put_buffer(s->pb, buf, ID3v1_TAG_SIZE);
272
        put_flush_packet(s->pb);
273
    }
274
    return 0;
275
}
276
#endif /* CONFIG_MP2_MUXER || CONFIG_MP3_MUXER */
277
278
#if CONFIG_MP2_MUXER
279
AVOutputFormat mp2_muxer = {
280
    "mp2",
281
    NULL_IF_CONFIG_SMALL("MPEG audio layer 2"),
282
    "audio/x-mpeg",
283
    "mp2,m2a",
284
    0,
285
    CODEC_ID_MP2,
286
    CODEC_ID_NONE,
287
    NULL,
288
    mp3_write_packet,
289
    mp3_write_trailer,
290
};
291
#endif
292
293
#if CONFIG_MP3_MUXER
294 0dc56bfa Andreas Öman
/**
295
 * Write an ID3v2.4 header at beginning of stream
296
 */
297
298 6a58e151 Fabrice Bellard
static int mp3_write_header(struct AVFormatContext *s)
299
{
300 078d89a2 Anton Khirnov
    AVMetadataTag *t = NULL;
301 0dc56bfa Andreas Öman
    int totlen = 0;
302 078d89a2 Anton Khirnov
    int64_t size_pos, cur_pos;
303 0dc56bfa Andreas Öman
304 899681cd Björn Axelsson
    put_be32(s->pb, MKBETAG('I', 'D', '3', 0x04)); /* ID3v2.4 */
305
    put_byte(s->pb, 0);
306
    put_byte(s->pb, 0); /* flags */
307 0dc56bfa Andreas Öman
308 078d89a2 Anton Khirnov
    /* reserve space for size */
309
    size_pos = url_ftell(s->pb);
310
    put_be32(s->pb, 0);
311
312
    while ((t = av_metadata_get(s->metadata, "", t, AV_METADATA_IGNORE_SUFFIX))) {
313
        uint32_t tag = 0;
314
315
        if (t->key[0] == 'T' && strcmp(t->key, "TSSE")) {
316
            int i;
317
            for (i = 0; *ff_id3v2_tags[i]; i++)
318
                if (AV_RB32(t->key) == AV_RB32(ff_id3v2_tags[i])) {
319
                    int len = strlen(t->value);
320
                    tag = AV_RB32(t->key);
321
                    totlen += len + ID3v2_HEADER_SIZE + 2;
322
                    id3v2_put_ttag(s, t->value, len + 1, tag);
323
                    break;
324
                }
325
        }
326
327
        if (!tag) { /* unknown tag, write as TXXX frame */
328
            int   len = strlen(t->key), len1 = strlen(t->value);
329
            char *buf = av_malloc(len + len1 + 2);
330
            if (!buf)
331
                return AVERROR(ENOMEM);
332
            tag = MKBETAG('T', 'X', 'X', 'X');
333
            strcpy(buf,           t->key);
334
            strcpy(buf + len + 1, t->value);
335
            id3v2_put_ttag(s, buf, len + len1 + 2, tag);
336
            totlen += len + len1 + ID3v2_HEADER_SIZE + 3;
337
            av_free(buf);
338
        }
339
    }
340
    if(!(s->streams[0]->codec->flags & CODEC_FLAG_BITEXACT)) {
341
        totlen += strlen(LIBAVFORMAT_IDENT) + ID3v2_HEADER_SIZE + 2;
342
        id3v2_put_ttag(s, LIBAVFORMAT_IDENT, strlen(LIBAVFORMAT_IDENT) + 1,
343
                       MKBETAG('T', 'S', 'S', 'E'));
344
    }
345
346
    cur_pos = url_ftell(s->pb);
347
    url_fseek(s->pb, size_pos, SEEK_SET);
348 0dc56bfa Andreas Öman
    id3v2_put_size(s, totlen);
349 078d89a2 Anton Khirnov
    url_fseek(s->pb, cur_pos, SEEK_SET);
350 0dc56bfa Andreas Öman
351 6a58e151 Fabrice Bellard
    return 0;
352
}
353
354 d2a067d1 Måns Rullgård
AVOutputFormat mp3_muxer = {
355 6a58e151 Fabrice Bellard
    "mp3",
356 bde15e74 Stefano Sabatini
    NULL_IF_CONFIG_SMALL("MPEG audio layer 3"),
357 6a58e151 Fabrice Bellard
    "audio/x-mpeg",
358
    "mp3",
359
    0,
360
    CODEC_ID_MP3,
361 d9133126 Carl Eugen Hoyos
    CODEC_ID_NONE,
362 6a58e151 Fabrice Bellard
    mp3_write_header,
363
    mp3_write_packet,
364
    mp3_write_trailer,
365 6378b062 Anton Khirnov
    .metadata_conv = ff_id3v2_metadata_conv,
366 6a58e151 Fabrice Bellard
};
367
#endif