[FFmpeg-cvslog] r16485 - in trunk/libavcodec: aac.c aac_parser.c aac_parser.h
superdump
subversion
Wed Jan 7 23:09:22 CET 2009
Author: superdump
Date: Wed Jan 7 23:09:21 2009
New Revision: 16485
Log:
Support ADTS AAC files in the ffaac decoder (limited to streams containing one
raw_data_block() per ADTS frame)
Patch by Alex Converse ( alex converse gmail com) based on a patch by Robert
Swain ( robert swain gmail com )
Added:
trunk/libavcodec/aac_parser.h
Modified:
trunk/libavcodec/aac.c
trunk/libavcodec/aac_parser.c
Modified: trunk/libavcodec/aac.c
==============================================================================
--- trunk/libavcodec/aac.c Wed Jan 7 21:45:39 2009 (r16484)
+++ trunk/libavcodec/aac.c Wed Jan 7 23:09:21 2009 (r16485)
@@ -86,6 +86,7 @@
#include "aactab.h"
#include "aacdectab.h"
#include "mpeg4audio.h"
+#include "aac_parser.h"
#include <assert.h>
#include <errno.h>
@@ -384,12 +385,24 @@ static av_cold int aac_decode_init(AVCod
ac->avccontext = avccontext;
- if (avccontext->extradata_size <= 0 ||
- decode_audio_specific_config(ac, avccontext->extradata, avccontext->extradata_size))
+ if (avccontext->extradata_size > 0) {
+ if(decode_audio_specific_config(ac, avccontext->extradata, avccontext->extradata_size))
+ return -1;
+ avccontext->sample_rate = ac->m4ac.sample_rate;
+ } else if (avccontext->channels > 0) {
+ enum ChannelPosition new_che_pos[4][MAX_ELEM_ID];
+ memset(new_che_pos, 0, 4 * MAX_ELEM_ID * sizeof(new_che_pos[0][0]));
+ if(set_default_channel_config(ac, new_che_pos, avccontext->channels - (avccontext->channels == 8)))
+ return -1;
+ if(output_configure(ac, ac->che_pos, new_che_pos))
+ return -1;
+ ac->m4ac.sample_rate = avccontext->sample_rate;
+ } else {
+ ff_log_missing_feature(ac->avccontext, "Implicit channel configuration is", 0);
return -1;
+ }
avccontext->sample_fmt = SAMPLE_FMT_S16;
- avccontext->sample_rate = ac->m4ac.sample_rate;
avccontext->frame_size = 1024;
AAC_INIT_VLC_STATIC( 0, 144);
@@ -1506,6 +1519,29 @@ static void spectral_to_sample(AACContex
}
}
+static int parse_adts_frame_header(AACContext * ac, GetBitContext * gb) {
+
+ int size;
+ AACADTSHeaderInfo hdr_info;
+
+ size = ff_aac_parse_header(gb, &hdr_info);
+ if (size > 0) {
+ if (hdr_info.chan_config)
+ ac->m4ac.chan_config = hdr_info.chan_config;
+ ac->m4ac.sample_rate = hdr_info.sample_rate;
+ ac->m4ac.sampling_index = hdr_info.sampling_index;
+ ac->m4ac.object_type = hdr_info.object_type;
+ }
+ if (hdr_info.num_aac_frames == 1) {
+ if (!hdr_info.crc_absent)
+ skip_bits(gb, 16);
+ } else {
+ ff_log_missing_feature(ac->avccontext, "More than one AAC RDB per ADTS frame is", 0);
+ return -1;
+ }
+ return size;
+}
+
static int aac_decode_frame(AVCodecContext * avccontext, void * data, int * data_size, const uint8_t * buf, int buf_size) {
AACContext * ac = avccontext->priv_data;
GetBitContext gb;
@@ -1514,6 +1550,13 @@ static int aac_decode_frame(AVCodecConte
init_get_bits(&gb, buf, buf_size*8);
+ if (show_bits(&gb, 12) == 0xfff) {
+ if ((err = parse_adts_frame_header(ac, &gb)) < 0) {
+ av_log(avccontext, AV_LOG_ERROR, "Error decoding AAC frame header.\n");
+ return -1;
+ }
+ }
+
// parse
while ((elem_type = get_bits(&gb, 3)) != TYPE_END) {
elem_id = get_bits(&gb, 4);
Modified: trunk/libavcodec/aac_parser.c
==============================================================================
--- trunk/libavcodec/aac_parser.c Wed Jan 7 21:45:39 2009 (r16484)
+++ trunk/libavcodec/aac_parser.c Wed Jan 7 23:09:21 2009 (r16485)
@@ -22,16 +22,64 @@
#include "parser.h"
#include "aac_ac3_parser.h"
+#include "aac_parser.h"
#include "bitstream.h"
#include "mpeg4audio.h"
#define AAC_HEADER_SIZE 7
+int ff_aac_parse_header(GetBitContext *gbc, AACADTSHeaderInfo *hdr)
+{
+ int size, rdb, ch, sr;
+ int aot, crc_abs;
+
+ if(get_bits(gbc, 12) != 0xfff)
+ return AAC_AC3_PARSE_ERROR_SYNC;
+
+ skip_bits1(gbc); /* id */
+ skip_bits(gbc, 2); /* layer */
+ crc_abs = get_bits1(gbc); /* protection_absent */
+ aot = get_bits(gbc, 2); /* profile_objecttype */
+ sr = get_bits(gbc, 4); /* sample_frequency_index */
+ if(!ff_mpeg4audio_sample_rates[sr])
+ return AAC_AC3_PARSE_ERROR_SAMPLE_RATE;
+ skip_bits1(gbc); /* private_bit */
+ ch = get_bits(gbc, 3); /* channel_configuration */
+
+ if(!ff_mpeg4audio_channels[ch])
+ return AAC_AC3_PARSE_ERROR_CHANNEL_CFG;
+
+ skip_bits1(gbc); /* original/copy */
+ skip_bits1(gbc); /* home */
+
+ /* adts_variable_header */
+ skip_bits1(gbc); /* copyright_identification_bit */
+ skip_bits1(gbc); /* copyright_identification_start */
+ size = get_bits(gbc, 13); /* aac_frame_length */
+ if(size < AAC_HEADER_SIZE)
+ return AAC_AC3_PARSE_ERROR_FRAME_SIZE;
+
+ skip_bits(gbc, 11); /* adts_buffer_fullness */
+ rdb = get_bits(gbc, 2); /* number_of_raw_data_blocks_in_frame */
+
+ hdr->object_type = aot;
+ hdr->chan_config = ch;
+ hdr->crc_absent = crc_abs;
+ hdr->num_aac_frames = rdb + 1;
+ hdr->sampling_index = sr;
+ hdr->sample_rate = ff_mpeg4audio_sample_rates[sr];
+ hdr->samples = (rdb + 1) * 1024;
+ hdr->bit_rate = size * 8 * hdr->sample_rate / hdr->samples;
+
+ return size;
+}
+
static int aac_sync(uint64_t state, AACAC3ParseContext *hdr_info,
int *need_next_header, int *new_frame_start)
{
GetBitContext bits;
- int size, rdb, ch, sr;
+ AACADTSHeaderInfo hdr;
+ int size;
union {
uint64_t u64;
uint8_t u8[8];
@@ -40,40 +88,14 @@ static int aac_sync(uint64_t state, AACA
tmp.u64 = be2me_64(state);
init_get_bits(&bits, tmp.u8+8-AAC_HEADER_SIZE, AAC_HEADER_SIZE * 8);
- if(get_bits(&bits, 12) != 0xfff)
- return 0;
-
- skip_bits1(&bits); /* id */
- skip_bits(&bits, 2); /* layer */
- skip_bits1(&bits); /* protection_absent */
- skip_bits(&bits, 2); /* profile_objecttype */
- sr = get_bits(&bits, 4); /* sample_frequency_index */
- if(!ff_mpeg4audio_sample_rates[sr])
- return 0;
- skip_bits1(&bits); /* private_bit */
- ch = get_bits(&bits, 3); /* channel_configuration */
- if(!ff_mpeg4audio_channels[ch])
- return 0;
- skip_bits1(&bits); /* original/copy */
- skip_bits1(&bits); /* home */
-
- /* adts_variable_header */
- skip_bits1(&bits); /* copyright_identification_bit */
- skip_bits1(&bits); /* copyright_identification_start */
- size = get_bits(&bits, 13); /* aac_frame_length */
- if(size < AAC_HEADER_SIZE)
+ if ((size = ff_aac_parse_header(&bits, &hdr)) < 0)
return 0;
-
- skip_bits(&bits, 11); /* adts_buffer_fullness */
- rdb = get_bits(&bits, 2); /* number_of_raw_data_blocks_in_frame */
-
- hdr_info->channels = ff_mpeg4audio_channels[ch];
- hdr_info->sample_rate = ff_mpeg4audio_sample_rates[sr];
- hdr_info->samples = (rdb + 1) * 1024;
- hdr_info->bit_rate = size * 8 * hdr_info->sample_rate / hdr_info->samples;
-
*need_next_header = 0;
*new_frame_start = 1;
+ hdr_info->sample_rate = hdr.sample_rate;
+ hdr_info->channels = ff_mpeg4audio_channels[hdr.chan_config];
+ hdr_info->samples = hdr.samples;
+ hdr_info->bit_rate = hdr.bit_rate;
return size;
}
Added: trunk/libavcodec/aac_parser.h
==============================================================================
--- /dev/null 00:00:00 1970 (empty, because file is newly added)
+++ trunk/libavcodec/aac_parser.h Wed Jan 7 23:09:21 2009 (r16485)
@@ -0,0 +1,53 @@
+/*
+ * AAC parser prototypes
+ * Copyright (c) 2003 Fabrice Bellard
+ * Copyright (c) 2003 Michael Niedermayer
+ *
+ * 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
+ */
+
+#ifndef AVCODEC_AAC_PARSER_H
+#define AVCODEC_AAC_PARSER_H
+
+#include <stdint.h>
+#include "aac_ac3_parser.h"
+#include "bitstream.h"
+
+typedef struct {
+ uint32_t sample_rate;
+ uint32_t samples;
+ uint32_t bit_rate;
+ uint8_t crc_absent;
+ uint8_t object_type;
+ uint8_t sampling_index;
+ uint8_t chan_config;
+ uint8_t num_aac_frames;
+} AACADTSHeaderInfo;
+
+/**
+ * Parses AAC frame header.
+ * Parses the ADTS frame header to the end of the variable header, which is
+ * the first 54 bits.
+ * @param gbc[in] BitContext containing the first 54 bits of the frame.
+ * @param hdr[out] Pointer to struct where header info is written.
+ * @return Returns 0 on success, -1 if there is a sync word mismatch,
+ * -2 if the version element is invalid, -3 if the sample rate
+ * element is invalid, or -4 if the bit rate element is invalid.
+ */
+int ff_aac_parse_header(GetBitContext *gbc, AACADTSHeaderInfo *hdr);
+
+#endif /* AVCODEC_AAC_PARSER_H */
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