3 * Copyright (c) 2006 Baptiste Coudurier <baptiste.coudurier@smartjog.com>
4 * Mans Rullgard <mans@mansr.com>
6 * This file is part of FFmpeg.
8 * FFmpeg is free software; you can redistribute it and/or
9 * modify it under the terms of the GNU Lesser General Public
10 * License as published by the Free Software Foundation; either
11 * version 2.1 of the License, or (at your option) any later version.
13 * FFmpeg is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16 * Lesser General Public License for more details.
18 * You should have received a copy of the GNU Lesser General Public
19 * License along with FFmpeg; if not, write to the Free Software
20 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
23 #include "libavcodec/get_bits.h"
24 #include "libavcodec/put_bits.h"
25 #include "libavcodec/avcodec.h"
26 #include "libavcodec/mpeg4audio.h"
27 #include "libavutil/opt.h"
32 #define ADTS_HEADER_SIZE 7
34 typedef struct ADTSContext {
38 int sample_rate_index;
44 uint8_t pce_data[MAX_PCE_SIZE];
47 #define ADTS_MAX_FRAME_BYTES ((1 << 14) - 1)
49 static int adts_decode_extradata(AVFormatContext *s, ADTSContext *adts, const uint8_t *buf, int size)
53 MPEG4AudioConfig m4ac;
56 init_get_bits(&gb, buf, size * 8);
57 off = avpriv_mpeg4audio_get_config2(&m4ac, buf, size, 1, s);
60 skip_bits_long(&gb, off);
61 adts->objecttype = m4ac.object_type - 1;
62 adts->sample_rate_index = m4ac.sampling_index;
63 adts->channel_conf = m4ac.chan_config;
65 if (adts->objecttype > 3U) {
66 av_log(s, AV_LOG_ERROR, "MPEG-4 AOT %d is not allowed in ADTS\n", adts->objecttype+1);
67 return AVERROR_INVALIDDATA;
69 if (adts->sample_rate_index == 15) {
70 av_log(s, AV_LOG_ERROR, "Escape sample rate index illegal in ADTS\n");
71 return AVERROR_INVALIDDATA;
73 if (get_bits(&gb, 1)) {
74 av_log(s, AV_LOG_ERROR, "960/120 MDCT window is not allowed in ADTS\n");
75 return AVERROR_INVALIDDATA;
77 if (get_bits(&gb, 1)) {
78 av_log(s, AV_LOG_ERROR, "Scalable configurations are not allowed in ADTS\n");
79 return AVERROR_INVALIDDATA;
81 if (get_bits(&gb, 1)) {
82 av_log(s, AV_LOG_ERROR, "Extension flag is not allowed in ADTS\n");
83 return AVERROR_INVALIDDATA;
85 if (!adts->channel_conf) {
86 init_put_bits(&pb, adts->pce_data, MAX_PCE_SIZE);
88 put_bits(&pb, 3, 5); //ID_PCE
89 adts->pce_size = (ff_copy_pce_data(&pb, &gb) + 3) / 8;
98 static int adts_init(AVFormatContext *s)
100 ADTSContext *adts = s->priv_data;
101 AVCodecParameters *par = s->streams[0]->codecpar;
103 if (par->codec_id != AV_CODEC_ID_AAC) {
104 av_log(s, AV_LOG_ERROR, "Only AAC streams can be muxed by the ADTS muxer\n");
105 return AVERROR(EINVAL);
107 if (par->extradata_size > 0)
108 return adts_decode_extradata(s, adts, par->extradata,
109 par->extradata_size);
114 static int adts_write_header(AVFormatContext *s)
116 ADTSContext *adts = s->priv_data;
119 ff_id3v2_write_simple(s, 4, ID3v2_DEFAULT_MAGIC);
124 static int adts_write_frame_header(ADTSContext *ctx,
125 uint8_t *buf, int size, int pce_size)
129 unsigned full_frame_size = (unsigned)ADTS_HEADER_SIZE + size + pce_size;
130 if (full_frame_size > ADTS_MAX_FRAME_BYTES) {
131 av_log(NULL, AV_LOG_ERROR, "ADTS frame size too large: %u (max %d)\n",
132 full_frame_size, ADTS_MAX_FRAME_BYTES);
133 return AVERROR_INVALIDDATA;
136 init_put_bits(&pb, buf, ADTS_HEADER_SIZE);
138 /* adts_fixed_header */
139 put_bits(&pb, 12, 0xfff); /* syncword */
140 put_bits(&pb, 1, ctx->mpeg_id); /* ID */
141 put_bits(&pb, 2, 0); /* layer */
142 put_bits(&pb, 1, 1); /* protection_absent */
143 put_bits(&pb, 2, ctx->objecttype); /* profile_objecttype */
144 put_bits(&pb, 4, ctx->sample_rate_index);
145 put_bits(&pb, 1, 0); /* private_bit */
146 put_bits(&pb, 3, ctx->channel_conf); /* channel_configuration */
147 put_bits(&pb, 1, 0); /* original_copy */
148 put_bits(&pb, 1, 0); /* home */
150 /* adts_variable_header */
151 put_bits(&pb, 1, 0); /* copyright_identification_bit */
152 put_bits(&pb, 1, 0); /* copyright_identification_start */
153 put_bits(&pb, 13, full_frame_size); /* aac_frame_length */
154 put_bits(&pb, 11, 0x7ff); /* adts_buffer_fullness */
155 put_bits(&pb, 2, 0); /* number_of_raw_data_blocks_in_frame */
162 static int adts_write_packet(AVFormatContext *s, AVPacket *pkt)
164 ADTSContext *adts = s->priv_data;
165 AVCodecParameters *par = s->streams[0]->codecpar;
166 AVIOContext *pb = s->pb;
167 uint8_t buf[ADTS_HEADER_SIZE];
171 if (!par->extradata_size) {
173 size_t side_data_size;
176 side_data = av_packet_get_side_data(pkt, AV_PKT_DATA_NEW_EXTRADATA,
178 if (side_data_size) {
179 ret = adts_decode_extradata(s, adts, side_data, side_data_size);
182 ret = ff_alloc_extradata(par, side_data_size);
185 memcpy(par->extradata, side_data, side_data_size);
188 if (adts->write_adts) {
189 int err = adts_write_frame_header(adts, buf, pkt->size,
193 avio_write(pb, buf, ADTS_HEADER_SIZE);
194 if (adts->pce_size) {
195 avio_write(pb, adts->pce_data, adts->pce_size);
199 avio_write(pb, pkt->data, pkt->size);
204 static int adts_write_trailer(AVFormatContext *s)
206 ADTSContext *adts = s->priv_data;
214 #define ENC AV_OPT_FLAG_ENCODING_PARAM
215 #define OFFSET(obj) offsetof(ADTSContext, obj)
216 static const AVOption options[] = {
217 { "write_id3v2", "Enable ID3v2 tag writing", OFFSET(id3v2tag), AV_OPT_TYPE_BOOL, {.i64 = 0}, 0, 1, ENC},
218 { "write_apetag", "Enable APE tag writing", OFFSET(apetag), AV_OPT_TYPE_BOOL, {.i64 = 0}, 0, 1, ENC},
219 { "write_mpeg2", "Set MPEG version to MPEG-2", OFFSET(mpeg_id), AV_OPT_TYPE_BOOL, {.i64 = 0}, 0, 1, ENC},
223 static const AVClass adts_muxer_class = {
224 .class_name = "ADTS muxer",
225 .item_name = av_default_item_name,
227 .version = LIBAVUTIL_VERSION_INT,
230 AVOutputFormat ff_adts_muxer = {
232 .long_name = NULL_IF_CONFIG_SMALL("ADTS AAC (Advanced Audio Coding)"),
233 .mime_type = "audio/aac",
234 .extensions = "aac,adts",
235 .priv_data_size = sizeof(ADTSContext),
236 .audio_codec = AV_CODEC_ID_AAC,
237 .video_codec = AV_CODEC_ID_NONE,
239 .write_header = adts_write_header,
240 .write_packet = adts_write_packet,
241 .write_trailer = adts_write_trailer,
242 .priv_class = &adts_muxer_class,
243 .flags = AVFMT_NOTIMESTAMPS,