0,0 → 1,205 |
/* |
* ADTS muxer. |
* Copyright (c) 2006 Baptiste Coudurier <baptiste.coudurier@smartjog.com> |
* Mans Rullgard <mans@mansr.com> |
* |
* This file is part of FFmpeg. |
* |
* FFmpeg is free software; you can redistribute it and/or |
* modify it under the terms of the GNU Lesser General Public |
* License as published by the Free Software Foundation; either |
* version 2.1 of the License, or (at your option) any later version. |
* |
* FFmpeg is distributed in the hope that it will be useful, |
* but WITHOUT ANY WARRANTY; without even the implied warranty of |
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
* Lesser General Public License for more details. |
* |
* You should have received a copy of the GNU Lesser General Public |
* License along with FFmpeg; if not, write to the Free Software |
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA |
*/ |
|
#include "libavcodec/get_bits.h" |
#include "libavcodec/put_bits.h" |
#include "libavcodec/avcodec.h" |
#include "libavcodec/mpeg4audio.h" |
#include "libavutil/opt.h" |
#include "avformat.h" |
#include "apetag.h" |
|
#define ADTS_HEADER_SIZE 7 |
|
typedef struct { |
AVClass *class; |
int write_adts; |
int objecttype; |
int sample_rate_index; |
int channel_conf; |
int pce_size; |
int apetag; |
uint8_t pce_data[MAX_PCE_SIZE]; |
} ADTSContext; |
|
#define ADTS_MAX_FRAME_BYTES ((1 << 13) - 1) |
|
static int adts_decode_extradata(AVFormatContext *s, ADTSContext *adts, uint8_t *buf, int size) |
{ |
GetBitContext gb; |
PutBitContext pb; |
MPEG4AudioConfig m4ac; |
int off; |
|
init_get_bits(&gb, buf, size * 8); |
off = avpriv_mpeg4audio_get_config(&m4ac, buf, size * 8, 1); |
if (off < 0) |
return off; |
skip_bits_long(&gb, off); |
adts->objecttype = m4ac.object_type - 1; |
adts->sample_rate_index = m4ac.sampling_index; |
adts->channel_conf = m4ac.chan_config; |
|
if (adts->objecttype > 3U) { |
av_log(s, AV_LOG_ERROR, "MPEG-4 AOT %d is not allowed in ADTS\n", adts->objecttype+1); |
return -1; |
} |
if (adts->sample_rate_index == 15) { |
av_log(s, AV_LOG_ERROR, "Escape sample rate index illegal in ADTS\n"); |
return -1; |
} |
if (get_bits(&gb, 1)) { |
av_log(s, AV_LOG_ERROR, "960/120 MDCT window is not allowed in ADTS\n"); |
return -1; |
} |
if (get_bits(&gb, 1)) { |
av_log(s, AV_LOG_ERROR, "Scalable configurations are not allowed in ADTS\n"); |
return -1; |
} |
if (get_bits(&gb, 1)) { |
av_log(s, AV_LOG_ERROR, "Extension flag is not allowed in ADTS\n"); |
return -1; |
} |
if (!adts->channel_conf) { |
init_put_bits(&pb, adts->pce_data, MAX_PCE_SIZE); |
|
put_bits(&pb, 3, 5); //ID_PCE |
adts->pce_size = (avpriv_copy_pce_data(&pb, &gb) + 3) / 8; |
flush_put_bits(&pb); |
} |
|
adts->write_adts = 1; |
|
return 0; |
} |
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static int adts_write_header(AVFormatContext *s) |
{ |
ADTSContext *adts = s->priv_data; |
AVCodecContext *avc = s->streams[0]->codec; |
|
if (avc->extradata_size > 0 && |
adts_decode_extradata(s, adts, avc->extradata, avc->extradata_size) < 0) |
return -1; |
|
return 0; |
} |
|
static int adts_write_frame_header(ADTSContext *ctx, |
uint8_t *buf, int size, int pce_size) |
{ |
PutBitContext pb; |
|
unsigned full_frame_size = (unsigned)ADTS_HEADER_SIZE + size + pce_size; |
if (full_frame_size > ADTS_MAX_FRAME_BYTES) { |
av_log(NULL, AV_LOG_ERROR, "ADTS frame size too large: %u (max %d)\n", |
full_frame_size, ADTS_MAX_FRAME_BYTES); |
return AVERROR_INVALIDDATA; |
} |
|
init_put_bits(&pb, buf, ADTS_HEADER_SIZE); |
|
/* adts_fixed_header */ |
put_bits(&pb, 12, 0xfff); /* syncword */ |
put_bits(&pb, 1, 0); /* ID */ |
put_bits(&pb, 2, 0); /* layer */ |
put_bits(&pb, 1, 1); /* protection_absent */ |
put_bits(&pb, 2, ctx->objecttype); /* profile_objecttype */ |
put_bits(&pb, 4, ctx->sample_rate_index); |
put_bits(&pb, 1, 0); /* private_bit */ |
put_bits(&pb, 3, ctx->channel_conf); /* channel_configuration */ |
put_bits(&pb, 1, 0); /* original_copy */ |
put_bits(&pb, 1, 0); /* home */ |
|
/* adts_variable_header */ |
put_bits(&pb, 1, 0); /* copyright_identification_bit */ |
put_bits(&pb, 1, 0); /* copyright_identification_start */ |
put_bits(&pb, 13, full_frame_size); /* aac_frame_length */ |
put_bits(&pb, 11, 0x7ff); /* adts_buffer_fullness */ |
put_bits(&pb, 2, 0); /* number_of_raw_data_blocks_in_frame */ |
|
flush_put_bits(&pb); |
|
return 0; |
} |
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static int adts_write_packet(AVFormatContext *s, AVPacket *pkt) |
{ |
ADTSContext *adts = s->priv_data; |
AVIOContext *pb = s->pb; |
uint8_t buf[ADTS_HEADER_SIZE]; |
|
if (!pkt->size) |
return 0; |
if (adts->write_adts) { |
int err = adts_write_frame_header(adts, buf, pkt->size, |
adts->pce_size); |
if (err < 0) |
return err; |
avio_write(pb, buf, ADTS_HEADER_SIZE); |
if (adts->pce_size) { |
avio_write(pb, adts->pce_data, adts->pce_size); |
adts->pce_size = 0; |
} |
} |
avio_write(pb, pkt->data, pkt->size); |
|
return 0; |
} |
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static int adts_write_trailer(AVFormatContext *s) |
{ |
ADTSContext *adts = s->priv_data; |
|
if (adts->apetag) |
ff_ape_write_tag(s); |
|
return 0; |
} |
|
#define ENC AV_OPT_FLAG_ENCODING_PARAM |
#define OFFSET(obj) offsetof(ADTSContext, obj) |
static const AVOption options[] = { |
{ "write_apetag", "Enable APE tag writing", OFFSET(apetag), AV_OPT_TYPE_INT, {.i64 = 0}, 0, 1, ENC}, |
{ NULL }, |
}; |
|
static const AVClass adts_muxer_class = { |
.class_name = "ADTS muxer", |
.item_name = av_default_item_name, |
.option = options, |
.version = LIBAVUTIL_VERSION_INT, |
}; |
|
AVOutputFormat ff_adts_muxer = { |
.name = "adts", |
.long_name = NULL_IF_CONFIG_SMALL("ADTS AAC (Advanced Audio Coding)"), |
.mime_type = "audio/aac", |
.extensions = "aac,adts", |
.priv_data_size = sizeof(ADTSContext), |
.audio_codec = AV_CODEC_ID_AAC, |
.video_codec = AV_CODEC_ID_NONE, |
.write_header = adts_write_header, |
.write_packet = adts_write_packet, |
.write_trailer = adts_write_trailer, |
.priv_class = &adts_muxer_class, |
}; |