blob: 5e006dd38f61bc95c5ba92912ad914f340b34b68
1 | /* |
2 | * ADTS muxer. |
3 | * Copyright (c) 2006 Baptiste Coudurier <baptiste.coudurier@smartjog.com> |
4 | * Mans Rullgard <mans@mansr.com> |
5 | * |
6 | * This file is part of FFmpeg. |
7 | * |
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. |
12 | * |
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. |
17 | * |
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 |
21 | */ |
22 | |
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" |
28 | #include "avformat.h" |
29 | #include "apetag.h" |
30 | #include "id3v2.h" |
31 | |
32 | #define ADTS_HEADER_SIZE 7 |
33 | |
34 | typedef struct ADTSContext { |
35 | AVClass *class; |
36 | int write_adts; |
37 | int objecttype; |
38 | int sample_rate_index; |
39 | int channel_conf; |
40 | int pce_size; |
41 | int apetag; |
42 | int id3v2tag; |
43 | uint8_t pce_data[MAX_PCE_SIZE]; |
44 | } ADTSContext; |
45 | |
46 | #define ADTS_MAX_FRAME_BYTES ((1 << 13) - 1) |
47 | |
48 | static int adts_decode_extradata(AVFormatContext *s, ADTSContext *adts, const uint8_t *buf, int size) |
49 | { |
50 | GetBitContext gb; |
51 | PutBitContext pb; |
52 | MPEG4AudioConfig m4ac; |
53 | int off; |
54 | |
55 | init_get_bits(&gb, buf, size * 8); |
56 | off = avpriv_mpeg4audio_get_config(&m4ac, buf, size * 8, 1); |
57 | if (off < 0) |
58 | return off; |
59 | skip_bits_long(&gb, off); |
60 | adts->objecttype = m4ac.object_type - 1; |
61 | adts->sample_rate_index = m4ac.sampling_index; |
62 | adts->channel_conf = m4ac.chan_config; |
63 | |
64 | if (adts->objecttype > 3U) { |
65 | av_log(s, AV_LOG_ERROR, "MPEG-4 AOT %d is not allowed in ADTS\n", adts->objecttype+1); |
66 | return AVERROR_INVALIDDATA; |
67 | } |
68 | if (adts->sample_rate_index == 15) { |
69 | av_log(s, AV_LOG_ERROR, "Escape sample rate index illegal in ADTS\n"); |
70 | return AVERROR_INVALIDDATA; |
71 | } |
72 | if (get_bits(&gb, 1)) { |
73 | av_log(s, AV_LOG_ERROR, "960/120 MDCT window is not allowed in ADTS\n"); |
74 | return AVERROR_INVALIDDATA; |
75 | } |
76 | if (get_bits(&gb, 1)) { |
77 | av_log(s, AV_LOG_ERROR, "Scalable configurations are not allowed in ADTS\n"); |
78 | return AVERROR_INVALIDDATA; |
79 | } |
80 | if (get_bits(&gb, 1)) { |
81 | av_log(s, AV_LOG_ERROR, "Extension flag is not allowed in ADTS\n"); |
82 | return AVERROR_INVALIDDATA; |
83 | } |
84 | if (!adts->channel_conf) { |
85 | init_put_bits(&pb, adts->pce_data, MAX_PCE_SIZE); |
86 | |
87 | put_bits(&pb, 3, 5); //ID_PCE |
88 | adts->pce_size = (avpriv_copy_pce_data(&pb, &gb) + 3) / 8; |
89 | flush_put_bits(&pb); |
90 | } |
91 | |
92 | adts->write_adts = 1; |
93 | |
94 | return 0; |
95 | } |
96 | |
97 | static int adts_write_header(AVFormatContext *s) |
98 | { |
99 | ADTSContext *adts = s->priv_data; |
100 | AVCodecParameters *par = s->streams[0]->codecpar; |
101 | |
102 | if (adts->id3v2tag) |
103 | ff_id3v2_write_simple(s, 4, ID3v2_DEFAULT_MAGIC); |
104 | if (par->extradata_size > 0) |
105 | return adts_decode_extradata(s, adts, par->extradata, |
106 | par->extradata_size); |
107 | |
108 | return 0; |
109 | } |
110 | |
111 | static int adts_write_frame_header(ADTSContext *ctx, |
112 | uint8_t *buf, int size, int pce_size) |
113 | { |
114 | PutBitContext pb; |
115 | |
116 | unsigned full_frame_size = (unsigned)ADTS_HEADER_SIZE + size + pce_size; |
117 | if (full_frame_size > ADTS_MAX_FRAME_BYTES) { |
118 | av_log(NULL, AV_LOG_ERROR, "ADTS frame size too large: %u (max %d)\n", |
119 | full_frame_size, ADTS_MAX_FRAME_BYTES); |
120 | return AVERROR_INVALIDDATA; |
121 | } |
122 | |
123 | init_put_bits(&pb, buf, ADTS_HEADER_SIZE); |
124 | |
125 | /* adts_fixed_header */ |
126 | put_bits(&pb, 12, 0xfff); /* syncword */ |
127 | put_bits(&pb, 1, 0); /* ID */ |
128 | put_bits(&pb, 2, 0); /* layer */ |
129 | put_bits(&pb, 1, 1); /* protection_absent */ |
130 | put_bits(&pb, 2, ctx->objecttype); /* profile_objecttype */ |
131 | put_bits(&pb, 4, ctx->sample_rate_index); |
132 | put_bits(&pb, 1, 0); /* private_bit */ |
133 | put_bits(&pb, 3, ctx->channel_conf); /* channel_configuration */ |
134 | put_bits(&pb, 1, 0); /* original_copy */ |
135 | put_bits(&pb, 1, 0); /* home */ |
136 | |
137 | /* adts_variable_header */ |
138 | put_bits(&pb, 1, 0); /* copyright_identification_bit */ |
139 | put_bits(&pb, 1, 0); /* copyright_identification_start */ |
140 | put_bits(&pb, 13, full_frame_size); /* aac_frame_length */ |
141 | put_bits(&pb, 11, 0x7ff); /* adts_buffer_fullness */ |
142 | put_bits(&pb, 2, 0); /* number_of_raw_data_blocks_in_frame */ |
143 | |
144 | flush_put_bits(&pb); |
145 | |
146 | return 0; |
147 | } |
148 | |
149 | static int adts_write_packet(AVFormatContext *s, AVPacket *pkt) |
150 | { |
151 | ADTSContext *adts = s->priv_data; |
152 | AVIOContext *pb = s->pb; |
153 | uint8_t buf[ADTS_HEADER_SIZE]; |
154 | |
155 | if (!pkt->size) |
156 | return 0; |
157 | if (adts->write_adts) { |
158 | int err = adts_write_frame_header(adts, buf, pkt->size, |
159 | adts->pce_size); |
160 | if (err < 0) |
161 | return err; |
162 | avio_write(pb, buf, ADTS_HEADER_SIZE); |
163 | if (adts->pce_size) { |
164 | avio_write(pb, adts->pce_data, adts->pce_size); |
165 | adts->pce_size = 0; |
166 | } |
167 | } |
168 | avio_write(pb, pkt->data, pkt->size); |
169 | |
170 | return 0; |
171 | } |
172 | |
173 | static int adts_write_trailer(AVFormatContext *s) |
174 | { |
175 | ADTSContext *adts = s->priv_data; |
176 | |
177 | if (adts->apetag) |
178 | ff_ape_write_tag(s); |
179 | |
180 | return 0; |
181 | } |
182 | |
183 | #define ENC AV_OPT_FLAG_ENCODING_PARAM |
184 | #define OFFSET(obj) offsetof(ADTSContext, obj) |
185 | static const AVOption options[] = { |
186 | { "write_id3v2", "Enable ID3v2 tag writing", OFFSET(id3v2tag), AV_OPT_TYPE_BOOL, {.i64 = 0}, 0, 1, ENC}, |
187 | { "write_apetag", "Enable APE tag writing", OFFSET(apetag), AV_OPT_TYPE_BOOL, {.i64 = 0}, 0, 1, ENC}, |
188 | { NULL }, |
189 | }; |
190 | |
191 | static const AVClass adts_muxer_class = { |
192 | .class_name = "ADTS muxer", |
193 | .item_name = av_default_item_name, |
194 | .option = options, |
195 | .version = LIBAVUTIL_VERSION_INT, |
196 | }; |
197 | |
198 | AVOutputFormat ff_adts_muxer = { |
199 | .name = "adts", |
200 | .long_name = NULL_IF_CONFIG_SMALL("ADTS AAC (Advanced Audio Coding)"), |
201 | .mime_type = "audio/aac", |
202 | .extensions = "aac,adts", |
203 | .priv_data_size = sizeof(ADTSContext), |
204 | .audio_codec = AV_CODEC_ID_AAC, |
205 | .video_codec = AV_CODEC_ID_NONE, |
206 | .write_header = adts_write_header, |
207 | .write_packet = adts_write_packet, |
208 | .write_trailer = adts_write_trailer, |
209 | .priv_class = &adts_muxer_class, |
210 | .flags = AVFMT_NOTIMESTAMPS, |
211 | }; |
212 |