FFmpeg: libavformat/id3v2enc.c Source File

00001 /*
00002  * ID3v2 header writer
00003  *
00004  * This file is part of FFmpeg.
00005  *
00006  * FFmpeg is free software; you can redistribute it and/or
00007  * modify it under the terms of the GNU Lesser General Public
00008  * License as published by the Free Software Foundation; either
00009  * version 2.1 of the License, or (at your option) any later version.
00010  *
00011  * FFmpeg is distributed in the hope that it will be useful,
00012  * but WITHOUT ANY WARRANTY; without even the implied warranty of
00013  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
00014  * Lesser General Public License for more details.
00015  *
00016  * You should have received a copy of the GNU Lesser General Public
00017  * License along with FFmpeg; if not, write to the Free Software
00018  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
00019  */
00020 
00021 #include <stdint.h>
00022 #include <string.h>
00023 
00024 #include "libavutil/avstring.h"
00025 #include "libavutil/dict.h"
00026 #include "libavutil/intreadwrite.h"
00027 #include "avformat.h"
00028 #include "avio.h"
00029 #include "id3v2.h"
00030 
00031 static void id3v2_put_size(AVIOContext *pb, int size)
00032 {
00033     avio_w8(pb, size >> 21 & 0x7f);
00034     avio_w8(pb, size >> 14 & 0x7f);
00035     avio_w8(pb, size >> 7  & 0x7f);
00036     avio_w8(pb, size       & 0x7f);
00037 }
00038 
00039 static int string_is_ascii(const uint8_t *str)
00040 {
00041     while (*str && *str < 128) str++;
00042     return !*str;
00043 }
00044 
00045 static void id3v2_encode_string(AVIOContext *pb, const uint8_t *str,
00046                                enum ID3v2Encoding enc)
00047 {
00048     int (*put)(AVIOContext*, const char*);
00049 
00050     if (enc == ID3v2_ENCODING_UTF16BOM) {
00051         avio_wl16(pb, 0xFEFF);      /* BOM */
00052         put = avio_put_str16le;
00053     } else
00054         put = avio_put_str;
00055 
00056     put(pb, str);
00057 }
00058 
00064 static int id3v2_put_ttag(ID3v2EncContext *id3, AVIOContext *avioc, const char *str1, const char *str2,
00065                           uint32_t tag, enum ID3v2Encoding enc)
00066 {
00067     int len;
00068     uint8_t *pb;
00069     AVIOContext *dyn_buf;
00070     if (avio_open_dyn_buf(&dyn_buf) < 0)
00071         return AVERROR(ENOMEM);
00072 
00073     /* check if the strings are ASCII-only and use UTF16 only if
00074      * they're not */
00075     if (enc == ID3v2_ENCODING_UTF16BOM && string_is_ascii(str1) &&
00076         (!str2 || string_is_ascii(str2)))
00077         enc = ID3v2_ENCODING_ISO8859;
00078 
00079     avio_w8(dyn_buf, enc);
00080     id3v2_encode_string(dyn_buf, str1, enc);
00081     if (str2)
00082         id3v2_encode_string(dyn_buf, str2, enc);
00083     len = avio_close_dyn_buf(dyn_buf, &pb);
00084 
00085     avio_wb32(avioc, tag);
00086     /* ID3v2.3 frame size is not synchsafe */
00087     if (id3->version == 3)
00088         avio_wb32(avioc, len);
00089     else
00090         id3v2_put_size(avioc, len);
00091     avio_wb16(avioc, 0);
00092     avio_write(avioc, pb, len);
00093 
00094     av_freep(&pb);
00095     return len + ID3v2_HEADER_SIZE;
00096 }
00097 
00098 static int id3v2_check_write_tag(ID3v2EncContext *id3, AVIOContext *pb, AVDictionaryEntry *t,
00099                                  const char table[][4], enum ID3v2Encoding enc)
00100 {
00101     uint32_t tag;
00102     int i;
00103 
00104     if (t->key[0] != 'T' || strlen(t->key) != 4)
00105         return -1;
00106     tag = AV_RB32(t->key);
00107     for (i = 0; *table[i]; i++)
00108         if (tag == AV_RB32(table[i]))
00109             return id3v2_put_ttag(id3, pb, t->value, NULL, tag, enc);
00110     return -1;
00111 }
00112 
00113 static void id3v2_3_metadata_split_date(AVDictionary **pm)
00114 {
00115     AVDictionaryEntry *mtag = NULL;
00116     AVDictionary *dst = NULL;
00117     const char *key, *value;
00118     char year[5] = {0}, day_month[5] = {0};
00119     int i;
00120 
00121     while ((mtag = av_dict_get(*pm, "", mtag, AV_DICT_IGNORE_SUFFIX))) {
00122         key = mtag->key;
00123         if (!av_strcasecmp(key, "date")) {
00124             /* split date tag using "YYYY-MM-DD" format into year and month/day segments */
00125             value = mtag->value;
00126             i = 0;
00127             while (value[i] >= '0' && value[i] <= '9') i++;
00128             if (value[i] == '\0' || value[i] == '-') {
00129                 av_strlcpy(year, value, sizeof(year));
00130                 av_dict_set(&dst, "TYER", year, 0);
00131 
00132                 if (value[i] == '-' &&
00133                     value[i+1] >= '0' && value[i+1] <= '1' &&
00134                     value[i+2] >= '0' && value[i+2] <= '9' &&
00135                     value[i+3] == '-' &&
00136                     value[i+4] >= '0' && value[i+4] <= '3' &&
00137                     value[i+5] >= '0' && value[i+5] <= '9' &&
00138                     (value[i+6] == '\0' || value[i+6] == ' ')) {
00139                     snprintf(day_month, sizeof(day_month), "%.2s%.2s", value + i + 4, value + i + 1);
00140                     av_dict_set(&dst, "TDAT", day_month, 0);
00141                 }
00142             } else
00143                 av_dict_set(&dst, key, value, 0);
00144         } else
00145             av_dict_set(&dst, key, mtag->value, 0);
00146     }
00147     av_dict_free(pm);
00148     *pm = dst;
00149 }
00150 
00151 void ff_id3v2_start(ID3v2EncContext *id3, AVIOContext *pb, int id3v2_version,
00152                     const char *magic)
00153 {
00154     id3->version = id3v2_version;
00155 
00156     avio_wb32(pb, MKBETAG(magic[0], magic[1], magic[2], id3v2_version));
00157     avio_w8(pb, 0);
00158     avio_w8(pb, 0); /* flags */
00159 
00160     /* reserve space for size */
00161     id3->size_pos = avio_tell(pb);
00162     avio_wb32(pb, 0);
00163 }
00164 
00165 int ff_id3v2_write_metadata(AVFormatContext *s, ID3v2EncContext *id3)
00166 {
00167     AVDictionaryEntry *t = NULL;
00168     int enc = id3->version == 3 ? ID3v2_ENCODING_UTF16BOM :
00169                                   ID3v2_ENCODING_UTF8;
00170 
00171     ff_metadata_conv(&s->metadata, ff_id3v2_34_metadata_conv, NULL);
00172     if (id3->version == 3)
00173         id3v2_3_metadata_split_date(&s->metadata);
00174     else if (id3->version == 4)
00175         ff_metadata_conv(&s->metadata, ff_id3v2_4_metadata_conv, NULL);
00176 
00177     while ((t = av_dict_get(s->metadata, "", t, AV_DICT_IGNORE_SUFFIX))) {
00178         int ret;
00179 
00180         if ((ret = id3v2_check_write_tag(id3, s->pb, t, ff_id3v2_tags, enc)) > 0) {
00181             id3->len += ret;
00182             continue;
00183         }
00184         if ((ret = id3v2_check_write_tag(id3, s->pb, t, id3->version == 3 ?
00185                                                ff_id3v2_3_tags : ff_id3v2_4_tags, enc)) > 0) {
00186             id3->len += ret;
00187             continue;
00188         }
00189 
00190         /* unknown tag, write as TXXX frame */
00191         if ((ret = id3v2_put_ttag(id3, s->pb, t->key, t->value, MKBETAG('T', 'X', 'X', 'X'), enc)) < 0)
00192             return ret;
00193         id3->len += ret;
00194     }
00195 
00196     return 0;
00197 }
00198 
00199 int ff_id3v2_write_apic(AVFormatContext *s, ID3v2EncContext *id3, AVPacket *pkt)
00200 {
00201     AVStream *st = s->streams[pkt->stream_index];
00202     AVDictionaryEntry *e;
00203 
00204     AVIOContext *dyn_buf;
00205     uint8_t     *buf;
00206     const CodecMime *mime = ff_id3v2_mime_tags;
00207     const char  *mimetype = NULL, *desc = "";
00208     int enc = id3->version == 3 ? ID3v2_ENCODING_UTF16BOM :
00209                                   ID3v2_ENCODING_UTF8;
00210     int i, len, type = 0;
00211 
00212     /* get the mimetype*/
00213     while (mime->id != CODEC_ID_NONE) {
00214         if (mime->id == st->codec->codec_id) {
00215             mimetype = mime->str;
00216             break;
00217         }
00218         mime++;
00219     }
00220     if (!mimetype) {
00221         av_log(s, AV_LOG_ERROR, "No mimetype is known for stream %d, cannot "
00222                "write an attached picture.\n", st->index);
00223         return AVERROR(EINVAL);
00224     }
00225 
00226     /* get the picture type */
00227     e = av_dict_get(st->metadata, "comment", NULL, 0);
00228     for (i = 0; e && i < FF_ARRAY_ELEMS(ff_id3v2_picture_types); i++) {
00229         if (strstr(ff_id3v2_picture_types[i], e->value) == ff_id3v2_picture_types[i]) {
00230             type = i;
00231             break;
00232         }
00233     }
00234 
00235     /* get the description */
00236     if ((e = av_dict_get(st->metadata, "title", NULL, 0)))
00237         desc = e->value;
00238 
00239     /* start writing */
00240     if (avio_open_dyn_buf(&dyn_buf) < 0)
00241         return AVERROR(ENOMEM);
00242 
00243     avio_w8(dyn_buf, enc);
00244     avio_put_str(dyn_buf, mimetype);
00245     avio_w8(dyn_buf, type);
00246     id3v2_encode_string(dyn_buf, desc, enc);
00247     avio_write(dyn_buf, pkt->data, pkt->size);
00248     len = avio_close_dyn_buf(dyn_buf, &buf);
00249 
00250     avio_wb32(s->pb, MKBETAG('A', 'P', 'I', 'C'));
00251     if (id3->version == 3)
00252         avio_wb32(s->pb, len);
00253     else
00254         id3v2_put_size(s->pb, len);
00255     avio_wb16(s->pb, 0);
00256     avio_write(s->pb, buf, len);
00257     av_freep(&buf);
00258 
00259     id3->len += len + ID3v2_HEADER_SIZE;
00260 
00261     return 0;
00262 }
00263 
00264 void ff_id3v2_finish(ID3v2EncContext *id3, AVIOContext *pb)
00265 {
00266     int64_t cur_pos = avio_tell(pb);
00267     avio_seek(pb, id3->size_pos, SEEK_SET);
00268     id3v2_put_size(pb, id3->len);
00269     avio_seek(pb, cur_pos, SEEK_SET);
00270 }
00271 
00272 int ff_id3v2_write_simple(struct AVFormatContext *s, int id3v2_version,
00273                           const char *magic)
00274 {
00275     ID3v2EncContext id3 = { 0 };
00276     int ret;
00277 
00278     ff_id3v2_start(&id3, s->pb, id3v2_version, magic);
00279     if ((ret = ff_id3v2_write_metadata(s, &id3)) < 0)
00280         return ret;
00281     ff_id3v2_finish(&id3, s->pb);
00282 
00283     return 0;
00284 }