3 * Copyright (c) 2003 Fabrice Bellard
5 * This file is part of Libav.
7 * Libav is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU Lesser General Public
9 * License as published by the Free Software Foundation; either
10 * version 2.1 of the License, or (at your option) any later version.
12 * Libav is distributed in the hope that it will be useful,
13 * 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.
17 * You should have received a copy of the GNU Lesser General Public
18 * License along with Libav; if not, write to the Free Software
19 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
23 #include "avio_internal.h"
27 #include "libavutil/avstring.h"
28 #include "libavcodec/mpegaudio.h"
29 #include "libavcodec/mpegaudiodata.h"
30 #include "libavcodec/mpegaudiodecheader.h"
31 #include "libavutil/intreadwrite.h"
32 #include "libavutil/opt.h"
33 #include "libavutil/dict.h"
34 #include "libavutil/avassert.h"
36 static int id3v1_set_string(AVFormatContext *s, const char *key,
37 uint8_t *buf, int buf_size)
39 AVDictionaryEntry *tag;
40 if ((tag = av_dict_get(s->metadata, key, NULL, 0)))
41 av_strlcpy(buf, tag->value, buf_size);
45 static int id3v1_create_tag(AVFormatContext *s, uint8_t *buf)
47 AVDictionaryEntry *tag;
50 memset(buf, 0, ID3v1_TAG_SIZE); /* fail safe */
54 count += id3v1_set_string(s, "TIT2", buf + 3, 30); //title
55 count += id3v1_set_string(s, "TPE1", buf + 33, 30); //author|artist
56 count += id3v1_set_string(s, "TALB", buf + 63, 30); //album
57 count += id3v1_set_string(s, "TDRL", buf + 93, 4); //date
58 count += id3v1_set_string(s, "comment", buf + 97, 30);
59 if ((tag = av_dict_get(s->metadata, "TRCK", NULL, 0))) { //track
61 buf[126] = atoi(tag->value);
64 buf[127] = 0xFF; /* default to unknown genre */
65 if ((tag = av_dict_get(s->metadata, "TCON", NULL, 0))) { //genre
66 for(i = 0; i <= ID3v1_GENRE_MAX; i++) {
67 if (!av_strcasecmp(tag->value, ff_id3v1_genre_str[i])) {
77 typedef struct MP3Context {
82 int64_t nb_frames_offset;
84 /* index of the audio stream */
86 /* number of attached pictures we still need to write */
89 /* audio packets are queued here until we get all the attached pictures */
90 AVPacketList *queue, *queue_end;
93 /* insert a dummy frame containing number of frames */
94 static void mp3_write_xing(AVFormatContext *s)
96 MP3Context *mp3 = s->priv_data;
97 AVCodecContext *codec = s->streams[mp3->audio_stream_idx]->codec;
98 int bitrate_idx = 1; // 32 kbps
99 int64_t xing_offset = (codec->channels == 2) ? 32 : 17;
101 MPADecodeHeader mpah;
102 int srate_idx, i, channels;
104 if (!s->pb->seekable)
107 for (i = 0; i < FF_ARRAY_ELEMS(avpriv_mpa_freq_tab); i++)
108 if (avpriv_mpa_freq_tab[i] == codec->sample_rate) {
112 if (i == FF_ARRAY_ELEMS(avpriv_mpa_freq_tab)) {
113 av_log(s, AV_LOG_ERROR, "Unsupported sample rate.\n");
117 switch (codec->channels) {
118 case 1: channels = MPA_MONO; break;
119 case 2: channels = MPA_STEREO; break;
120 default: av_log(s, AV_LOG_ERROR, "Unsupported number of channels.\n"); return;
123 /* dummy MPEG audio header */
124 header = 0xff << 24; // sync
125 header |= (0x7 << 5 | 0x3 << 3 | 0x1 << 1 | 0x1) << 16; // sync/mpeg-1/layer 3/no crc*/
126 header |= (bitrate_idx << 4 | srate_idx << 2) << 8;
127 header |= channels << 6;
128 avio_wb32(s->pb, header);
130 avpriv_mpegaudio_decode_header(&mpah, header);
132 ffio_fill(s->pb, 0, xing_offset);
133 ffio_wfourcc(s->pb, "Xing");
134 avio_wb32(s->pb, 0x1); // only number of frames
135 mp3->nb_frames_offset = avio_tell(s->pb);
138 mpah.frame_size -= 4 + xing_offset + 4 + 4 + 4;
139 ffio_fill(s->pb, 0, mpah.frame_size);
142 static int mp3_queue_flush(AVFormatContext *s)
144 MP3Context *mp3 = s->priv_data;
146 int ret = 0, write = 1;
148 ff_id3v2_finish(&mp3->id3, s->pb);
151 while ((pktl = mp3->queue)) {
152 if (write && (ret = ff_raw_write_packet(s, &pktl->pkt)) < 0)
154 av_free_packet(&pktl->pkt);
155 mp3->queue = pktl->next;
158 mp3->queue_end = NULL;
162 static int mp3_write_trailer(struct AVFormatContext *s)
164 uint8_t buf[ID3v1_TAG_SIZE];
165 MP3Context *mp3 = s->priv_data;
167 if (mp3 && mp3->pics_to_write) {
168 av_log(s, AV_LOG_WARNING, "No packets were sent for some of the "
169 "attached pictures.\n");
173 /* write the id3v1 tag */
174 if (mp3 && mp3->write_id3v1 && id3v1_create_tag(s, buf) > 0) {
175 avio_write(s->pb, buf, ID3v1_TAG_SIZE);
178 /* write number of frames */
179 if (mp3 && mp3->nb_frames_offset) {
180 avio_seek(s->pb, mp3->nb_frames_offset, SEEK_SET);
181 avio_wb32(s->pb, s->streams[mp3->audio_stream_idx]->nb_frames);
182 avio_seek(s->pb, 0, SEEK_END);
191 AVOutputFormat ff_mp2_muxer = {
193 .long_name = NULL_IF_CONFIG_SMALL("MPEG audio layer 2"),
194 .mime_type = "audio/x-mpeg",
195 .extensions = "mp2,m2a",
196 .audio_codec = CODEC_ID_MP2,
197 .video_codec = CODEC_ID_NONE,
198 .write_packet = ff_raw_write_packet,
199 .write_trailer = mp3_write_trailer,
205 static const AVOption options[] = {
206 { "id3v2_version", "Select ID3v2 version to write. Currently 3 and 4 are supported.",
207 offsetof(MP3Context, id3v2_version), AV_OPT_TYPE_INT, {.dbl = 4}, 3, 4, AV_OPT_FLAG_ENCODING_PARAM},
208 { "write_id3v1", "Enable ID3v1 writing. ID3v1 tags are written in UTF-8 which may not be supported by most software.",
209 offsetof(MP3Context, write_id3v1), AV_OPT_TYPE_INT, {.dbl = 0}, 0, 1, AV_OPT_FLAG_ENCODING_PARAM},
213 static const AVClass mp3_muxer_class = {
214 .class_name = "MP3 muxer",
215 .item_name = av_default_item_name,
217 .version = LIBAVUTIL_VERSION_INT,
220 static int mp3_write_packet(AVFormatContext *s, AVPacket *pkt)
222 MP3Context *mp3 = s->priv_data;
224 if (pkt->stream_index == mp3->audio_stream_idx) {
225 if (mp3->pics_to_write) {
226 /* buffer audio packets until we get all the pictures */
227 AVPacketList *pktl = av_mallocz(sizeof(*pktl));
229 return AVERROR(ENOMEM);
232 pkt->destruct = NULL;
235 mp3->queue_end->next = pktl;
238 mp3->queue_end = pktl;
240 return ff_raw_write_packet(s, pkt);
244 /* warn only once for each stream */
245 if (s->streams[pkt->stream_index]->nb_frames == 1) {
246 av_log(s, AV_LOG_WARNING, "Got more than one picture in stream %d,"
247 " ignoring.\n", pkt->stream_index);
249 if (!mp3->pics_to_write || s->streams[pkt->stream_index]->nb_frames >= 1)
252 if ((ret = ff_id3v2_write_apic(s, &mp3->id3, pkt)) < 0)
254 mp3->pics_to_write--;
256 /* flush the buffered audio packets */
257 if (!mp3->pics_to_write &&
258 (ret = mp3_queue_flush(s)) < 0)
266 * Write an ID3v2 header at beginning of stream
269 static int mp3_write_header(struct AVFormatContext *s)
271 MP3Context *mp3 = s->priv_data;
274 /* check the streams -- we want exactly one audio and arbitrary number of
275 * video (attached pictures) */
276 mp3->audio_stream_idx = -1;
277 for (i = 0; i < s->nb_streams; i++) {
278 AVStream *st = s->streams[i];
279 if (st->codec->codec_type == AVMEDIA_TYPE_AUDIO) {
280 if (mp3->audio_stream_idx >= 0 || st->codec->codec_id != CODEC_ID_MP3) {
281 av_log(s, AV_LOG_ERROR, "Invalid audio stream. Exactly one MP3 "
282 "audio stream is required.\n");
283 return AVERROR(EINVAL);
285 mp3->audio_stream_idx = i;
286 } else if (st->codec->codec_type != AVMEDIA_TYPE_VIDEO) {
287 av_log(s, AV_LOG_ERROR, "Only audio streams and pictures are allowed in MP3.\n");
288 return AVERROR(EINVAL);
291 if (mp3->audio_stream_idx < 0) {
292 av_log(s, AV_LOG_ERROR, "No audio stream present.\n");
293 return AVERROR(EINVAL);
295 mp3->pics_to_write = s->nb_streams - 1;
297 ff_id3v2_start(&mp3->id3, s->pb, mp3->id3v2_version, ID3v2_DEFAULT_MAGIC);
298 ret = ff_id3v2_write_metadata(s, &mp3->id3);
302 if (!mp3->pics_to_write) {
303 ff_id3v2_finish(&mp3->id3, s->pb);
310 AVOutputFormat ff_mp3_muxer = {
312 .long_name = NULL_IF_CONFIG_SMALL("MPEG audio layer 3"),
313 .mime_type = "audio/x-mpeg",
315 .priv_data_size = sizeof(MP3Context),
316 .audio_codec = CODEC_ID_MP3,
317 .video_codec = CODEC_ID_PNG,
318 .write_header = mp3_write_header,
319 .write_packet = mp3_write_packet,
320 .write_trailer = mp3_write_trailer,
321 .flags = AVFMT_NOTIMESTAMPS,
322 .priv_class = &mp3_muxer_class,