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/bitstream.h"
26 #define ADTS_HEADER_SIZE 7
31 int sample_rate_index;
35 static int decode_extradata(AVFormatContext *s, ADTSContext *adts, uint8_t *buf, int size)
39 init_get_bits(&gb, buf, size * 8);
40 adts->objecttype = get_bits(&gb, 5) - 1;
41 adts->sample_rate_index = get_bits(&gb, 4);
42 adts->channel_conf = get_bits(&gb, 4);
44 if (adts->objecttype > 3) {
45 av_log(s, AV_LOG_ERROR, "MPEG-4 AOT %d is not allowed in ADTS\n", adts->objecttype);
48 if (adts->sample_rate_index == 15) {
49 av_log(s, AV_LOG_ERROR, "Escape sample rate index illegal in ADTS\n");
52 if (adts->channel_conf == 0) {
53 ff_log_missing_feature(s, "PCE based channel configuration", 0);
62 static int adts_write_header(AVFormatContext *s)
64 ADTSContext *adts = s->priv_data;
65 AVCodecContext *avc = s->streams[0]->codec;
67 if(avc->extradata_size > 0 &&
68 decode_extradata(s, adts, avc->extradata, avc->extradata_size) < 0)
74 static int adts_write_frame_header(AVFormatContext *s, int size)
76 ADTSContext *ctx = s->priv_data;
78 uint8_t buf[ADTS_HEADER_SIZE];
80 init_put_bits(&pb, buf, ADTS_HEADER_SIZE);
82 /* adts_fixed_header */
83 put_bits(&pb, 12, 0xfff); /* syncword */
84 put_bits(&pb, 1, 0); /* ID */
85 put_bits(&pb, 2, 0); /* layer */
86 put_bits(&pb, 1, 1); /* protection_absent */
87 put_bits(&pb, 2, ctx->objecttype); /* profile_objecttype */
88 put_bits(&pb, 4, ctx->sample_rate_index);
89 put_bits(&pb, 1, 0); /* private_bit */
90 put_bits(&pb, 3, ctx->channel_conf); /* channel_configuration */
91 put_bits(&pb, 1, 0); /* original_copy */
92 put_bits(&pb, 1, 0); /* home */
94 /* adts_variable_header */
95 put_bits(&pb, 1, 0); /* copyright_identification_bit */
96 put_bits(&pb, 1, 0); /* copyright_identification_start */
97 put_bits(&pb, 13, ADTS_HEADER_SIZE + size); /* aac_frame_length */
98 put_bits(&pb, 11, 0x7ff); /* adts_buffer_fullness */
99 put_bits(&pb, 2, 0); /* number_of_raw_data_blocks_in_frame */
102 put_buffer(s->pb, buf, ADTS_HEADER_SIZE);
107 static int adts_write_packet(AVFormatContext *s, AVPacket *pkt)
109 ADTSContext *adts = s->priv_data;
110 ByteIOContext *pb = s->pb;
115 adts_write_frame_header(s, pkt->size);
116 put_buffer(pb, pkt->data, pkt->size);
117 put_flush_packet(pb);
122 AVOutputFormat adts_muxer = {
124 NULL_IF_CONFIG_SMALL("ADTS AAC"),