mirror of
https://github.com/axiomatic-systems/Bento4.git
synced 2026-01-19 00:05:12 +08:00
334 lines
13 KiB
C++
334 lines
13 KiB
C++
/*****************************************************************
|
|
|
|
|
| AP4 - AAC Info
|
|
|
|
|
| Copyright 2002-2009 Axiomatic Systems, LLC
|
|
|
|
|
|
|
|
| This file is part of Bento4/AP4 (MP4 Atom Processing Library).
|
|
|
|
|
| Unless you have obtained Bento4 under a difference license,
|
|
| this version of Bento4 is Bento4|GPL.
|
|
| Bento4|GPL is free software; you can redistribute it and/or modify
|
|
| it under the terms of the GNU General Public License as published by
|
|
| the Free Software Foundation; either version 2, or (at your option)
|
|
| any later version.
|
|
|
|
|
| Bento4|GPL 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 General Public License for more details.
|
|
|
|
|
| You should have received a copy of the GNU General Public License
|
|
| along with Bento4|GPL; see the file COPYING. If not, write to the
|
|
| Free Software Foundation, 59 Temple Place - Suite 330, Boston, MA
|
|
| 02111-1307, USA.
|
|
|
|
|
****************************************************************/
|
|
|
|
/*----------------------------------------------------------------------
|
|
| includes
|
|
+---------------------------------------------------------------------*/
|
|
#include "Ap4BitStream.h"
|
|
#include "Ap4Mp4AudioInfo.h"
|
|
#include "Ap4DataBuffer.h"
|
|
#include "Ap4SampleDescription.h"
|
|
|
|
/*----------------------------------------------------------------------
|
|
| constants
|
|
+---------------------------------------------------------------------*/
|
|
const unsigned int AP4_AAC_MAX_SAMPLING_FREQUENCY_INDEX = 12;
|
|
static const unsigned int AP4_AacSamplingFreqTable[13] =
|
|
{
|
|
96000, 88200, 64000, 48000,
|
|
44100, 32000, 24000, 22050,
|
|
16000, 12000, 11025, 8000,
|
|
7350
|
|
};
|
|
|
|
/*----------------------------------------------------------------------
|
|
| AP4_Mp4AudioDsiParser
|
|
+---------------------------------------------------------------------*/
|
|
class AP4_Mp4AudioDsiParser
|
|
{
|
|
public:
|
|
AP4_Mp4AudioDsiParser(const AP4_UI08* data, AP4_Size data_size) :
|
|
m_Data(data, data_size),
|
|
m_Position(0) {}
|
|
|
|
AP4_Size BitsLeft() { return 8*m_Data.GetDataSize()-m_Position; }
|
|
AP4_UI32 ReadBits(unsigned int n) {
|
|
AP4_UI32 result = 0;
|
|
const AP4_UI08* data = m_Data.GetData();
|
|
while (n) {
|
|
unsigned int bits_avail = 8-(m_Position%8);
|
|
unsigned int chunk_size = bits_avail >= n ? n : bits_avail;
|
|
unsigned int chunk_bits = (((unsigned int)(data[m_Position/8]))>>(bits_avail-chunk_size))&((1<<chunk_size)-1);
|
|
result = (result << chunk_size) | chunk_bits;
|
|
n -= chunk_size;
|
|
m_Position += chunk_size;
|
|
}
|
|
|
|
return result;
|
|
}
|
|
|
|
private:
|
|
AP4_DataBuffer m_Data;
|
|
unsigned int m_Position;
|
|
};
|
|
|
|
/*----------------------------------------------------------------------
|
|
| AP4_Mp4AudioDecoderConfig::AP4_Mp4AudioDecoderConfig
|
|
+---------------------------------------------------------------------*/
|
|
AP4_Mp4AudioDecoderConfig::AP4_Mp4AudioDecoderConfig()
|
|
{
|
|
Reset();
|
|
}
|
|
|
|
/*----------------------------------------------------------------------
|
|
| AP4_Mp4AudioDecoderConfig::Reset
|
|
+---------------------------------------------------------------------*/
|
|
void
|
|
AP4_Mp4AudioDecoderConfig::Reset()
|
|
{
|
|
m_ObjectType = 0;
|
|
m_SamplingFrequencyIndex = 0;
|
|
m_SamplingFrequency = 0;
|
|
m_ChannelCount = 0;
|
|
m_ChannelConfiguration = CHANNEL_CONFIG_NONE;
|
|
m_FrameLengthFlag = false;
|
|
m_DependsOnCoreCoder = false;
|
|
m_CoreCoderDelay = 0;
|
|
m_Extension.m_SbrPresent = false;
|
|
m_Extension.m_PsPresent = false;
|
|
m_Extension.m_ObjectType = 0;
|
|
m_Extension.m_SamplingFrequencyIndex = 0;
|
|
m_Extension.m_SamplingFrequency = 0;
|
|
}
|
|
|
|
/*----------------------------------------------------------------------
|
|
| AP4_Mp4AudioDecoderConfig::ParseAudioObjectType
|
|
+---------------------------------------------------------------------*/
|
|
AP4_Result
|
|
AP4_Mp4AudioDecoderConfig::ParseAudioObjectType(AP4_Mp4AudioDsiParser& parser, AP4_UI08& object_type)
|
|
{
|
|
if (parser.BitsLeft() < 5) return AP4_ERROR_INVALID_FORMAT;
|
|
object_type = (AP4_UI08)parser.ReadBits(5);
|
|
if ((int)object_type == 31) {
|
|
if (parser.BitsLeft() < 6) return AP4_ERROR_INVALID_FORMAT;
|
|
object_type = (AP4_UI08)(32 + parser.ReadBits(6));
|
|
}
|
|
return AP4_SUCCESS;
|
|
}
|
|
|
|
/*----------------------------------------------------------------------
|
|
| AP4_Mp4AudioDecoderConfig::ParseExtension
|
|
+---------------------------------------------------------------------*/
|
|
AP4_Result
|
|
AP4_Mp4AudioDecoderConfig::ParseExtension(AP4_Mp4AudioDsiParser& parser)
|
|
{
|
|
if (parser.BitsLeft() < 16) return AP4_ERROR_INVALID_FORMAT;
|
|
unsigned int sync_extension_type = parser.ReadBits(11);
|
|
if (sync_extension_type == 0x2b7) {
|
|
AP4_Result result = ParseAudioObjectType(parser, m_Extension.m_ObjectType);
|
|
if (AP4_FAILED(result)) return result;
|
|
if (m_Extension.m_ObjectType == AP4_MPEG4_AUDIO_OBJECT_TYPE_SBR) {
|
|
m_Extension.m_SbrPresent = (parser.ReadBits(1) == 1);
|
|
if (m_Extension.m_SbrPresent) {
|
|
result = ParseSamplingFrequency(parser,
|
|
m_Extension.m_SamplingFrequencyIndex,
|
|
m_Extension.m_SamplingFrequency);
|
|
if (AP4_FAILED(result)) return result;
|
|
if (parser.BitsLeft() >= 12) {
|
|
sync_extension_type = parser.ReadBits(11);
|
|
if (sync_extension_type == 0x548) {
|
|
m_Extension.m_PsPresent = (parser.ReadBits(1) == 1);
|
|
}
|
|
}
|
|
}
|
|
} else if (m_Extension.m_ObjectType == AP4_MPEG4_AUDIO_OBJECT_TYPE_ER_BSAC) {
|
|
m_Extension.m_SbrPresent = (parser.ReadBits(1) == 1);
|
|
if (m_Extension.m_SbrPresent) {
|
|
result = ParseSamplingFrequency(parser,
|
|
m_Extension.m_SamplingFrequencyIndex,
|
|
m_Extension.m_SamplingFrequency);
|
|
if (AP4_FAILED(result)) return result;
|
|
}
|
|
parser.ReadBits(4); // extensionChannelConfiguration
|
|
}
|
|
}
|
|
return AP4_SUCCESS;
|
|
}
|
|
|
|
/*----------------------------------------------------------------------
|
|
| AP4_Mp4AudioDecoderConfig::ParseGASpecificInfo
|
|
+---------------------------------------------------------------------*/
|
|
AP4_Result
|
|
AP4_Mp4AudioDecoderConfig::ParseGASpecificInfo(AP4_Mp4AudioDsiParser& parser)
|
|
{
|
|
if (parser.BitsLeft() < 2) return AP4_ERROR_INVALID_FORMAT;
|
|
m_FrameLengthFlag = (parser.ReadBits(1) == 1);
|
|
m_DependsOnCoreCoder = (parser.ReadBits(1) == 1);
|
|
if (m_DependsOnCoreCoder) {
|
|
if (parser.BitsLeft() < 14) return AP4_ERROR_INVALID_FORMAT;
|
|
m_CoreCoderDelay = parser.ReadBits(14);
|
|
} else {
|
|
m_CoreCoderDelay = 0;
|
|
}
|
|
if (parser.BitsLeft() < 1) return AP4_ERROR_INVALID_FORMAT;
|
|
unsigned int extensionFlag = parser.ReadBits(1);
|
|
if (m_ChannelConfiguration == CHANNEL_CONFIG_NONE) {
|
|
/*program_config_element (); */
|
|
return AP4_ERROR_NOT_SUPPORTED;
|
|
}
|
|
if (m_ObjectType == AP4_MPEG4_AUDIO_OBJECT_TYPE_AAC_SCALABLE ||
|
|
m_ObjectType == AP4_MPEG4_AUDIO_OBJECT_TYPE_ER_AAC_SCALABLE) {
|
|
if (parser.BitsLeft() < 3) return AP4_ERROR_INVALID_FORMAT;
|
|
parser.ReadBits(3); // layerNr
|
|
}
|
|
if (extensionFlag) {
|
|
if (m_ObjectType == AP4_MPEG4_AUDIO_OBJECT_TYPE_ER_BSAC) {
|
|
if (parser.BitsLeft() < 16) return AP4_ERROR_INVALID_FORMAT;
|
|
parser.ReadBits(16); // numOfSubFrame (5); layer_length (11)
|
|
}
|
|
if (m_ObjectType == AP4_MPEG4_AUDIO_OBJECT_TYPE_ER_AAC_LC ||
|
|
m_ObjectType == AP4_MPEG4_AUDIO_OBJECT_TYPE_ER_AAC_SCALABLE ||
|
|
m_ObjectType == AP4_MPEG4_AUDIO_OBJECT_TYPE_ER_AAC_LD) {
|
|
if (parser.BitsLeft() < 3) return AP4_ERROR_INVALID_FORMAT;
|
|
parser.ReadBits(3); // aacSectionDataResilienceFlag (1)
|
|
// aacScalefactorDataResilienceFlag (1)
|
|
// aacSpectralDataResilienceFlag (1)
|
|
}
|
|
if (parser.BitsLeft() < 1) return AP4_ERROR_INVALID_FORMAT;
|
|
unsigned int extensionFlag3 = parser.ReadBits(1);
|
|
if (extensionFlag3) {
|
|
return AP4_ERROR_NOT_SUPPORTED;
|
|
}
|
|
}
|
|
|
|
return AP4_SUCCESS;
|
|
}
|
|
|
|
/*----------------------------------------------------------------------
|
|
| AP4_Mp4AudioDecoderConfig::ParseSamplingFrequency
|
|
+---------------------------------------------------------------------*/
|
|
AP4_Result
|
|
AP4_Mp4AudioDecoderConfig::ParseSamplingFrequency(AP4_Mp4AudioDsiParser& parser,
|
|
unsigned int& sampling_frequency_index,
|
|
unsigned int& sampling_frequency)
|
|
{
|
|
if (parser.BitsLeft() < 4) {
|
|
return AP4_ERROR_INVALID_FORMAT;
|
|
}
|
|
|
|
sampling_frequency_index = parser.ReadBits(4);
|
|
if (sampling_frequency_index == 0xF) {
|
|
if (parser.BitsLeft() < 24) {
|
|
return AP4_ERROR_INVALID_FORMAT;
|
|
}
|
|
sampling_frequency = parser.ReadBits(24);
|
|
} else if (sampling_frequency_index <= AP4_AAC_MAX_SAMPLING_FREQUENCY_INDEX) {
|
|
sampling_frequency = AP4_AacSamplingFreqTable[sampling_frequency_index];
|
|
} else {
|
|
sampling_frequency = 0;
|
|
return AP4_ERROR_INVALID_FORMAT;
|
|
}
|
|
|
|
return AP4_SUCCESS;
|
|
}
|
|
|
|
/*----------------------------------------------------------------------
|
|
| AP4_Mp4AudioDecoderConfig::Parse
|
|
+---------------------------------------------------------------------*/
|
|
AP4_Result
|
|
AP4_Mp4AudioDecoderConfig::Parse(const unsigned char* data,
|
|
AP4_Size data_size)
|
|
{
|
|
AP4_Result result;
|
|
AP4_Mp4AudioDsiParser bits(data, data_size);
|
|
|
|
// default config
|
|
Reset();
|
|
|
|
// parse the audio object type
|
|
result = ParseAudioObjectType(bits, m_ObjectType);
|
|
if (AP4_FAILED(result)) return result;
|
|
|
|
// parse the sampling frequency
|
|
result = ParseSamplingFrequency(bits,
|
|
m_SamplingFrequencyIndex,
|
|
m_SamplingFrequency);
|
|
if (AP4_FAILED(result)) return result;
|
|
|
|
if (bits.BitsLeft() < 4) {
|
|
return AP4_ERROR_INVALID_FORMAT;
|
|
}
|
|
m_ChannelConfiguration = (ChannelConfiguration)bits.ReadBits(4);
|
|
m_ChannelCount = (unsigned int)m_ChannelConfiguration;
|
|
if (m_ChannelCount == 7) {
|
|
m_ChannelCount = 8;
|
|
} else if (m_ChannelCount > 7) {
|
|
m_ChannelCount = 0;
|
|
}
|
|
|
|
if (m_ObjectType == AP4_MPEG4_AUDIO_OBJECT_TYPE_SBR ||
|
|
m_ObjectType == AP4_MPEG4_AUDIO_OBJECT_TYPE_PS) {
|
|
m_Extension.m_ObjectType = AP4_MPEG4_AUDIO_OBJECT_TYPE_SBR;
|
|
m_Extension.m_SbrPresent = true;
|
|
m_Extension.m_PsPresent = m_ObjectType == AP4_MPEG4_AUDIO_OBJECT_TYPE_PS;
|
|
result = ParseSamplingFrequency(bits,
|
|
m_Extension.m_SamplingFrequencyIndex,
|
|
m_Extension.m_SamplingFrequency);
|
|
if (AP4_FAILED(result)) return result;
|
|
result = ParseAudioObjectType(bits, m_ObjectType);
|
|
if (AP4_FAILED(result)) return result;
|
|
if (m_ObjectType == AP4_MPEG4_AUDIO_OBJECT_TYPE_ER_BSAC) {
|
|
if (bits.BitsLeft() < 4) return AP4_ERROR_INVALID_FORMAT;
|
|
bits.ReadBits(4); // extensionChannelConfiguration (4)
|
|
}
|
|
} else {
|
|
m_Extension.m_ObjectType = 0;
|
|
m_Extension.m_SamplingFrequency = 0;
|
|
m_Extension.m_SamplingFrequencyIndex = 0;
|
|
m_Extension.m_SbrPresent = false;
|
|
m_Extension.m_PsPresent = false;
|
|
}
|
|
|
|
switch (m_ObjectType) {
|
|
case AP4_MPEG4_AUDIO_OBJECT_TYPE_AAC_MAIN:
|
|
case AP4_MPEG4_AUDIO_OBJECT_TYPE_AAC_LC:
|
|
case AP4_MPEG4_AUDIO_OBJECT_TYPE_AAC_SSR:
|
|
case AP4_MPEG4_AUDIO_OBJECT_TYPE_AAC_LTP:
|
|
case AP4_MPEG4_AUDIO_OBJECT_TYPE_AAC_SCALABLE:
|
|
case AP4_MPEG4_AUDIO_OBJECT_TYPE_TWINVQ:
|
|
case AP4_MPEG4_AUDIO_OBJECT_TYPE_ER_AAC_LC:
|
|
case AP4_MPEG4_AUDIO_OBJECT_TYPE_ER_AAC_LTP:
|
|
case AP4_MPEG4_AUDIO_OBJECT_TYPE_ER_AAC_SCALABLE:
|
|
case AP4_MPEG4_AUDIO_OBJECT_TYPE_ER_AAC_LD:
|
|
case AP4_MPEG4_AUDIO_OBJECT_TYPE_ER_TWINVQ:
|
|
case AP4_MPEG4_AUDIO_OBJECT_TYPE_ER_BSAC:
|
|
result = ParseGASpecificInfo(bits);
|
|
if (result == AP4_SUCCESS) {
|
|
if (m_Extension.m_ObjectType != AP4_MPEG4_AUDIO_OBJECT_TYPE_SBR &&
|
|
bits.BitsLeft() >= 16) {
|
|
result = ParseExtension(bits);
|
|
}
|
|
}
|
|
if (result == AP4_ERROR_NOT_SUPPORTED) {
|
|
// not a fatal error
|
|
result = AP4_SUCCESS;
|
|
}
|
|
if (result != AP4_SUCCESS) return result;
|
|
break;
|
|
|
|
default:
|
|
return AP4_ERROR_NOT_SUPPORTED;
|
|
}
|
|
|
|
return AP4_SUCCESS;
|
|
}
|
|
|
|
|
|
|
|
|