0,0 → 1,118 |
/* |
* MPEG-2/4 AAC ADTS to MPEG-4 Audio Specific Configuration bitstream filter |
* Copyright (c) 2009 Alex Converse <alex.converse@gmail.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 "avcodec.h" |
#include "aacadtsdec.h" |
#include "put_bits.h" |
#include "get_bits.h" |
#include "mpeg4audio.h" |
#include "internal.h" |
|
typedef struct AACBSFContext { |
int first_frame_done; |
} AACBSFContext; |
|
/** |
* This filter creates an MPEG-4 AudioSpecificConfig from an MPEG-2/4 |
* ADTS header and removes the ADTS header. |
*/ |
static int aac_adtstoasc_filter(AVBitStreamFilterContext *bsfc, |
AVCodecContext *avctx, const char *args, |
uint8_t **poutbuf, int *poutbuf_size, |
const uint8_t *buf, int buf_size, |
int keyframe) |
{ |
GetBitContext gb; |
PutBitContext pb; |
AACADTSHeaderInfo hdr; |
|
AACBSFContext *ctx = bsfc->priv_data; |
|
init_get_bits(&gb, buf, AAC_ADTS_HEADER_SIZE*8); |
|
*poutbuf = (uint8_t*) buf; |
*poutbuf_size = buf_size; |
|
if (avctx->extradata) |
if (show_bits(&gb, 12) != 0xfff) |
return 0; |
|
if (avpriv_aac_parse_header(&gb, &hdr) < 0) { |
av_log(avctx, AV_LOG_ERROR, "Error parsing ADTS frame header!\n"); |
return -1; |
} |
|
if (!hdr.crc_absent && hdr.num_aac_frames > 1) { |
avpriv_report_missing_feature(avctx, |
"Multiple RDBs per frame with CRC"); |
return AVERROR_PATCHWELCOME; |
} |
|
buf += AAC_ADTS_HEADER_SIZE + 2*!hdr.crc_absent; |
buf_size -= AAC_ADTS_HEADER_SIZE + 2*!hdr.crc_absent; |
|
if (!ctx->first_frame_done) { |
int pce_size = 0; |
uint8_t pce_data[MAX_PCE_SIZE]; |
if (!hdr.chan_config) { |
init_get_bits(&gb, buf, buf_size * 8); |
if (get_bits(&gb, 3) != 5) { |
avpriv_report_missing_feature(avctx, |
"PCE-based channel configuration " |
"without PCE as first syntax " |
"element"); |
return AVERROR_PATCHWELCOME; |
} |
init_put_bits(&pb, pce_data, MAX_PCE_SIZE); |
pce_size = avpriv_copy_pce_data(&pb, &gb)/8; |
flush_put_bits(&pb); |
buf_size -= get_bits_count(&gb)/8; |
buf += get_bits_count(&gb)/8; |
} |
avctx->extradata_size = 2 + pce_size; |
avctx->extradata = av_mallocz(avctx->extradata_size + FF_INPUT_BUFFER_PADDING_SIZE); |
|
init_put_bits(&pb, avctx->extradata, avctx->extradata_size); |
put_bits(&pb, 5, hdr.object_type); |
put_bits(&pb, 4, hdr.sampling_index); |
put_bits(&pb, 4, hdr.chan_config); |
put_bits(&pb, 1, 0); //frame length - 1024 samples |
put_bits(&pb, 1, 0); //does not depend on core coder |
put_bits(&pb, 1, 0); //is not extension |
flush_put_bits(&pb); |
if (pce_size) { |
memcpy(avctx->extradata + 2, pce_data, pce_size); |
} |
|
ctx->first_frame_done = 1; |
} |
|
*poutbuf = (uint8_t*) buf; |
*poutbuf_size = buf_size; |
|
return 0; |
} |
|
AVBitStreamFilter ff_aac_adtstoasc_bsf = { |
.name = "aac_adtstoasc", |
.priv_data_size = sizeof(AACBSFContext), |
.filter = aac_adtstoasc_filter, |
}; |