3 * Copyright (c) 2003 Fabrice Bellard
5 * This file is part of FFmpeg.
7 * FFmpeg 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 * FFmpeg 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 FFmpeg; 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 "libavcodec/mpegaudio.h"
34 #include "libavcodec/mpegaudiodata.h"
35 #include "libavcodec/mpegaudiodecheader.h"
36 #include "libavformat/avio_internal.h"
37 #include "libavutil/dict.h"
38 #include "libavutil/avassert.h"
40 static int id3v1_set_string(AVFormatContext *s, const char *key,
41 uint8_t *buf, int buf_size)
43 AVDictionaryEntry *tag;
44 if ((tag = av_dict_get(s->metadata, key, NULL, 0)))
45 av_strlcpy(buf, tag->value, buf_size);
49 static int id3v1_create_tag(AVFormatContext *s, uint8_t *buf)
51 AVDictionaryEntry *tag;
54 memset(buf, 0, ID3v1_TAG_SIZE); /* fail safe */
58 /* we knowingly overspecify each tag length by one byte to compensate for the mandatory null byte added by av_strlcpy */
59 count += id3v1_set_string(s, "TIT2", buf + 3, 30 + 1); //title
60 count += id3v1_set_string(s, "TPE1", buf + 33, 30 + 1); //author|artist
61 count += id3v1_set_string(s, "TALB", buf + 63, 30 + 1); //album
62 count += id3v1_set_string(s, "TDRL", buf + 93, 4 + 1); //date
63 count += id3v1_set_string(s, "comment", buf + 97, 30 + 1);
64 if ((tag = av_dict_get(s->metadata, "TRCK", NULL, 0))) { //track
66 buf[126] = atoi(tag->value);
69 buf[127] = 0xFF; /* default to unknown genre */
70 if ((tag = av_dict_get(s->metadata, "TCON", NULL, 0))) { //genre
71 for(i = 0; i <= ID3v1_GENRE_MAX; i++) {
72 if (!av_strcasecmp(tag->value, ff_id3v1_genre_str[i])) {
82 #define VBR_NUM_BAGS 400
83 #define VBR_TOC_SIZE 100
85 typedef struct MP3Context {
90 int64_t frames_offset;
96 uint64_t bag[VBR_NUM_BAGS];
98 int has_variable_bitrate;
100 /* index of the audio stream */
101 int audio_stream_idx;
102 /* number of attached pictures we still need to write */
105 /* audio packets are queued here until we get all the attached pictures */
106 AVPacketList *queue, *queue_end;
109 static const int64_t xing_offtbl[2][2] = {{32, 17}, {17,9}};
112 * Write an empty XING header and initialize respective data.
114 static int mp3_write_xing(AVFormatContext *s)
116 MP3Context *mp3 = s->priv_data;
117 AVCodecContext *codec = s->streams[mp3->audio_stream_idx]->codec;
119 int best_bitrate_idx = -1;
120 int best_bitrate_error= INT_MAX;
122 int32_t header, mask;
124 int srate_idx, ver = 0, i, channels;
126 const char *vendor = (codec->flags & CODEC_FLAG_BITEXACT) ? "Lavf" : LIBAVFORMAT_IDENT;
128 if (!s->pb->seekable)
131 for (i = 0; i < FF_ARRAY_ELEMS(avpriv_mpa_freq_tab); i++) {
132 const uint16_t base_freq = avpriv_mpa_freq_tab[i];
133 if (codec->sample_rate == base_freq) ver = 0x3; // MPEG 1
134 else if (codec->sample_rate == base_freq / 2) ver = 0x2; // MPEG 2
135 else if (codec->sample_rate == base_freq / 4) ver = 0x0; // MPEG 2.5
140 if (i == FF_ARRAY_ELEMS(avpriv_mpa_freq_tab)) {
141 av_log(s, AV_LOG_WARNING, "Unsupported sample rate, not writing Xing header.\n");
145 switch (codec->channels) {
146 case 1: channels = MPA_MONO; break;
147 case 2: channels = MPA_STEREO; break;
148 default: av_log(s, AV_LOG_WARNING, "Unsupported number of channels, not writing Xing header.\n"); return -1;
151 /* dummy MPEG audio header */
152 header = 0xff << 24; // sync
153 header |= (0x7 << 5 | ver << 3 | 0x1 << 1 | 0x1) << 16; // sync/audio-version/layer 3/no crc*/
154 header |= (srate_idx << 2) << 8;
155 header |= channels << 6;
157 for (bitrate_idx=1; bitrate_idx<15; bitrate_idx++) {
159 avpriv_mpegaudio_decode_header(&c, header | (bitrate_idx << (4+8)));
160 error= FFABS(c.bit_rate - codec->bit_rate);
161 if(error < best_bitrate_error){
162 best_bitrate_error= error;
163 best_bitrate_idx = bitrate_idx;
166 av_assert0(best_bitrate_idx >= 0);
168 for (bitrate_idx= best_bitrate_idx;; bitrate_idx++) {
169 if (15 == bitrate_idx)
171 mask = bitrate_idx << (4+8);
173 avpriv_mpegaudio_decode_header(&c, header);
174 xing_offset=xing_offtbl[c.lsf == 1][c.nb_channels == 1];
178 + 4 // frames/size/toc flags
181 + VBR_TOC_SIZE // toc
185 if (needed <= c.frame_size)
190 avio_wb32(s->pb, header);
191 ffio_fill(s->pb, 0, xing_offset);
192 avio_wb32(s->pb, MKBETAG('X', 'i', 'n', 'g'));
193 avio_wb32(s->pb, 0x01 | 0x02 | 0x04); // frames/size/toc
195 mp3->frames_offset = avio_tell(s->pb);
196 mp3->size = c.frame_size;
201 avio_wb32(s->pb, 0); // frames
202 avio_wb32(s->pb, 0); // size
205 for (i = 0; i < VBR_TOC_SIZE; ++i)
206 avio_w8(s->pb, (uint8_t)(255 * i / VBR_TOC_SIZE));
208 for (i = 0; i < strlen(vendor); ++i)
209 avio_w8(s->pb, vendor[i]);
212 avio_wb24(s->pb, FFMAX(codec->delay - 528 - 1, 0)<<12);
214 ffio_fill(s->pb, 0, c.frame_size - needed);
221 * Add a frame to XING data.
222 * Following lame's "VbrTag.c".
224 static void mp3_xing_add_frame(AVFormatContext *s, AVPacket *pkt)
226 MP3Context *mp3 = s->priv_data;
230 mp3->size += pkt->size;
232 if (mp3->want == ++mp3->seen) {
233 mp3->bag[mp3->pos] = mp3->size;
235 if (VBR_NUM_BAGS == ++mp3->pos) {
236 /* shrink table to half size by throwing away each second bag. */
237 for (i = 1; i < VBR_NUM_BAGS; i += 2)
238 mp3->bag[i >> 1] = mp3->bag[i];
240 /* double wanted amount per bag. */
242 /* adjust current position to half of table size. */
250 static void mp3_fix_xing(AVFormatContext *s)
252 MP3Context *mp3 = s->priv_data;
257 /* replace "Xing" identification string with "Info" for CBR files. */
258 if (!mp3->has_variable_bitrate) {
259 int64_t tag_offset = mp3->frames_offset
260 - 4 // frames/size/toc flags
262 avio_seek(s->pb, tag_offset, SEEK_SET);
263 avio_wb32(s->pb, MKBETAG('I', 'n', 'f', 'o'));
266 avio_seek(s->pb, mp3->frames_offset, SEEK_SET);
267 avio_wb32(s->pb, mp3->frames);
268 avio_wb32(s->pb, mp3->size);
270 avio_w8(s->pb, 0); // first toc entry has to be zero.
272 for (i = 1; i < VBR_TOC_SIZE; ++i) {
273 int j = i * mp3->pos / VBR_TOC_SIZE;
274 int seek_point = 256LL * mp3->bag[j] / mp3->size;
275 avio_w8(s->pb, FFMIN(seek_point, 255));
279 avio_seek(s->pb, 0, SEEK_END);
282 static int mp3_write_packet_internal(AVFormatContext *s, AVPacket *pkt)
284 if (! pkt || ! pkt->data || pkt->size < 4)
285 return ff_raw_write_packet(s, pkt);
287 MP3Context *mp3 = s->priv_data;
291 avpriv_mpegaudio_decode_header(&c, AV_RB32(pkt->data));
293 if (!mp3->initial_bitrate)
294 mp3->initial_bitrate = c.bit_rate;
295 if (!mp3->has_variable_bitrate) {
296 if ((c.bit_rate == 0) || (mp3->initial_bitrate != c.bit_rate))
297 mp3->has_variable_bitrate = 1;
300 #ifdef FILTER_VBR_HEADERS
301 /* filter out XING and INFO headers. */
302 base = 4 + xing_offtbl[c.lsf == 1][c.nb_channels == 1];
304 if (base + 4 <= pkt->size) {
305 uint32_t v = AV_RB32(pkt->data + base);
307 if (MKBETAG('X','i','n','g') == v || MKBETAG('I','n','f','o') == v)
311 /* filter out VBRI headers. */
314 if (base + 4 <= pkt->size && MKBETAG('V','B','R','I') == AV_RB32(pkt->data + base))
318 if (mp3->frames_offset)
319 mp3_xing_add_frame(s, pkt);
321 return ff_raw_write_packet(s, pkt);
325 static int mp3_queue_flush(AVFormatContext *s)
327 MP3Context *mp3 = s->priv_data;
329 int ret = 0, write = 1;
331 ff_id3v2_finish(&mp3->id3, s->pb);
334 while ((pktl = mp3->queue)) {
335 if (write && (ret = mp3_write_packet_internal(s, &pktl->pkt)) < 0)
337 av_free_packet(&pktl->pkt);
338 mp3->queue = pktl->next;
341 mp3->queue_end = NULL;
345 static int mp2_write_trailer(struct AVFormatContext *s)
347 uint8_t buf[ID3v1_TAG_SIZE];
348 MP3Context *mp3 = s->priv_data;
350 if (mp3 && mp3->pics_to_write) {
351 av_log(s, AV_LOG_WARNING, "No packets were sent for some of the "
352 "attached pictures.\n");
356 /* write the id3v1 tag */
357 if (mp3 && mp3->write_id3v1 && id3v1_create_tag(s, buf) > 0) {
358 avio_write(s->pb, buf, ID3v1_TAG_SIZE);
361 /* write number of frames */
362 if (mp3 && mp3->frames_offset) {
363 avio_seek(s->pb, mp3->frames_offset, SEEK_SET);
364 avio_wb32(s->pb, s->streams[mp3->audio_stream_idx]->nb_frames);
365 avio_seek(s->pb, 0, SEEK_END);
374 AVOutputFormat ff_mp2_muxer = {
376 .long_name = NULL_IF_CONFIG_SMALL("MPEG audio layer 2"),
377 .mime_type = "audio/x-mpeg",
378 .extensions = "mp2,m2a",
379 .audio_codec = CODEC_ID_MP2,
380 .video_codec = CODEC_ID_NONE,
381 .write_packet = ff_raw_write_packet,
382 .write_trailer = mp2_write_trailer,
383 .flags = AVFMT_NOTIMESTAMPS,
389 static const AVOption options[] = {
390 { "id3v2_version", "Select ID3v2 version to write. Currently 3 and 4 are supported.",
391 offsetof(MP3Context, id3v2_version), AV_OPT_TYPE_INT, {.dbl = 4}, 3, 4, AV_OPT_FLAG_ENCODING_PARAM},
392 { "write_id3v1", "Enable ID3v1 writing. ID3v1 tags are written in UTF-8 which may not be supported by most software.",
393 offsetof(MP3Context, write_id3v1), AV_OPT_TYPE_INT, {.dbl = 0}, 0, 1, AV_OPT_FLAG_ENCODING_PARAM},
397 static const AVClass mp3_muxer_class = {
398 .class_name = "MP3 muxer",
399 .item_name = av_default_item_name,
401 .version = LIBAVUTIL_VERSION_INT,
404 static int mp3_write_packet(AVFormatContext *s, AVPacket *pkt)
406 MP3Context *mp3 = s->priv_data;
408 if (pkt->stream_index == mp3->audio_stream_idx) {
409 if (mp3->pics_to_write) {
410 /* buffer audio packets until we get all the pictures */
411 AVPacketList *pktl = av_mallocz(sizeof(*pktl));
413 return AVERROR(ENOMEM);
416 pkt->destruct = NULL;
419 mp3->queue_end->next = pktl;
422 mp3->queue_end = pktl;
424 return mp3_write_packet_internal(s, pkt);
428 /* warn only once for each stream */
429 if (s->streams[pkt->stream_index]->nb_frames == 1) {
430 av_log(s, AV_LOG_WARNING, "Got more than one picture in stream %d,"
431 " ignoring.\n", pkt->stream_index);
433 if (!mp3->pics_to_write || s->streams[pkt->stream_index]->nb_frames >= 1)
436 if ((ret = ff_id3v2_write_apic(s, &mp3->id3, pkt)) < 0)
438 mp3->pics_to_write--;
440 /* flush the buffered audio packets */
441 if (!mp3->pics_to_write &&
442 (ret = mp3_queue_flush(s)) < 0)
450 * Write an ID3v2 header at beginning of stream
453 static int mp3_write_header(struct AVFormatContext *s)
455 MP3Context *mp3 = s->priv_data;
458 /* check the streams -- we want exactly one audio and arbitrary number of
459 * video (attached pictures) */
460 mp3->audio_stream_idx = -1;
461 for (i = 0; i < s->nb_streams; i++) {
462 AVStream *st = s->streams[i];
463 if (st->codec->codec_type == AVMEDIA_TYPE_AUDIO) {
464 if (mp3->audio_stream_idx >= 0 || st->codec->codec_id != CODEC_ID_MP3) {
465 av_log(s, AV_LOG_ERROR, "Invalid audio stream. Exactly one MP3 "
466 "audio stream is required.\n");
467 return AVERROR(EINVAL);
469 mp3->audio_stream_idx = i;
470 } else if (st->codec->codec_type != AVMEDIA_TYPE_VIDEO) {
471 av_log(s, AV_LOG_ERROR, "Only audio streams and pictures are allowed in MP3.\n");
472 return AVERROR(EINVAL);
475 if (mp3->audio_stream_idx < 0) {
476 av_log(s, AV_LOG_ERROR, "No audio stream present.\n");
477 return AVERROR(EINVAL);
479 mp3->pics_to_write = s->nb_streams - 1;
481 ff_id3v2_start(&mp3->id3, s->pb, mp3->id3v2_version, ID3v2_DEFAULT_MAGIC);
482 ret = ff_id3v2_write_metadata(s, &mp3->id3);
486 if (!mp3->pics_to_write) {
487 ff_id3v2_finish(&mp3->id3, s->pb);
494 static int mp3_write_trailer(AVFormatContext *s)
496 MP3Context *mp3 = s->priv_data;
497 int ret=mp2_write_trailer(s);
502 if (mp3->frames_offset)
508 AVOutputFormat ff_mp3_muxer = {
510 .long_name = NULL_IF_CONFIG_SMALL("MPEG audio layer 3"),
511 .mime_type = "audio/x-mpeg",
513 .priv_data_size = sizeof(MP3Context),
514 .audio_codec = CODEC_ID_MP3,
515 .video_codec = CODEC_ID_PNG,
516 .write_header = mp3_write_header,
517 .write_packet = mp3_write_packet,
518 .write_trailer = mp3_write_trailer,
519 .flags = AVFMT_NOTIMESTAMPS,
520 .priv_class = &mp3_muxer_class,