4 * This file is part of Libav.
6 * Libav is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU Lesser General Public
8 * License as published by the Free Software Foundation; either
9 * version 2.1 of the License, or (at your option) any later version.
11 * Libav is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14 * Lesser General Public License for more details.
16 * You should have received a copy of the GNU Lesser General Public
17 * License along with Libav; if not, write to the Free Software
18 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
23 #include "libavutil/dict.h"
24 #include "libavutil/intreadwrite.h"
29 static void id3v2_put_size(AVFormatContext *s, int size)
31 avio_w8(s->pb, size >> 21 & 0x7f);
32 avio_w8(s->pb, size >> 14 & 0x7f);
33 avio_w8(s->pb, size >> 7 & 0x7f);
34 avio_w8(s->pb, size & 0x7f);
37 static int string_is_ascii(const uint8_t *str)
39 while (*str && *str < 128) str++;
44 * Write a text frame with one (normal frames) or two (TXXX frames) strings
45 * according to encoding (only UTF-8 or UTF-16+BOM supported).
46 * @return number of bytes written or a negative error code.
48 static int id3v2_put_ttag(AVFormatContext *s, const char *str1, const char *str2,
49 uint32_t tag, enum ID3v2Encoding enc)
53 int (*put)(AVIOContext*, const char*);
55 if (avio_open_dyn_buf(&dyn_buf) < 0)
56 return AVERROR(ENOMEM);
58 /* check if the strings are ASCII-only and use UTF16 only if
60 if (enc == ID3v2_ENCODING_UTF16BOM && string_is_ascii(str1) &&
61 (!str2 || string_is_ascii(str2)))
62 enc = ID3v2_ENCODING_ISO8859;
64 avio_w8(dyn_buf, enc);
65 if (enc == ID3v2_ENCODING_UTF16BOM) {
66 avio_wl16(dyn_buf, 0xFEFF); /* BOM */
67 put = avio_put_str16le;
74 len = avio_close_dyn_buf(dyn_buf, &pb);
76 avio_wb32(s->pb, tag);
77 id3v2_put_size(s, len);
79 avio_write(s->pb, pb, len);
82 return len + ID3v2_HEADER_SIZE;
85 static int id3v2_check_write_tag(AVFormatContext *s, AVDictionaryEntry *t, const char table[][4],
86 enum ID3v2Encoding enc)
91 if (t->key[0] != 'T' || strlen(t->key) != 4)
93 tag = AV_RB32(t->key);
94 for (i = 0; *table[i]; i++)
95 if (tag == AV_RB32(table[i]))
96 return id3v2_put_ttag(s, t->value, NULL, tag, enc);
100 int ff_id3v2_write(struct AVFormatContext *s, int id3v2_version,
103 int64_t size_pos, cur_pos;
104 AVDictionaryEntry *t = NULL;
106 int totlen = 0, enc = id3v2_version == 3 ? ID3v2_ENCODING_UTF16BOM :
110 avio_wb32(s->pb, MKBETAG(magic[0], magic[1], magic[2], id3v2_version));
112 avio_w8(s->pb, 0); /* flags */
114 /* reserve space for size */
115 size_pos = avio_tell(s->pb);
118 ff_metadata_conv(&s->metadata, ff_id3v2_34_metadata_conv, NULL);
119 if (id3v2_version == 4)
120 ff_metadata_conv(&s->metadata, ff_id3v2_4_metadata_conv, NULL);
122 while ((t = av_dict_get(s->metadata, "", t, AV_DICT_IGNORE_SUFFIX))) {
125 if ((ret = id3v2_check_write_tag(s, t, ff_id3v2_tags, enc)) > 0) {
129 if ((ret = id3v2_check_write_tag(s, t, id3v2_version == 3 ?
130 ff_id3v2_3_tags : ff_id3v2_4_tags, enc)) > 0) {
135 /* unknown tag, write as TXXX frame */
136 if ((ret = id3v2_put_ttag(s, t->key, t->value, MKBETAG('T', 'X', 'X', 'X'), enc)) < 0)
141 cur_pos = avio_tell(s->pb);
142 avio_seek(s->pb, size_pos, SEEK_SET);
143 id3v2_put_size(s, totlen);
144 avio_seek(s->pb, cur_pos, SEEK_SET);