ISO Base Media File Format

isobmff.md

AAC

ISO/IEC 14496-3, 1.6.2.1 AudioSpecificConfig

AudioSpecificConfig() {
	audioObjectType = GetAudioObjectType();
	samplingFrequencyIndex; // 4 bslbf
	if (samplingFrequencyIndex == 0xf) {
		samplingFrequency; // 24 uimsbf
	}
	channelConfiguration; // 4 bslbf
	sbrPresentFlag = -1;
	psPresentFlag = -1;
	if (audioObjectType == 5 || audioObjectType == 29) {
		// ...
	}
	else {
		extensionAudioObjectType = 0;
	}
	switch (audioObjectType) {
	case 1: case 2: case 3: case 4: //...
		GASpecificConfig();
		break:
	case ...:
		//...
	}
	if (extensionAudioObjectType != 5 && bits_to_decode() >= 16) {
		//...
	}

GetAudioObjectType() {
	audioObjectType; // 5 uimsbf
	if (audioObjectType == 31) {
		audioObjectType = 32 + audioObjectTypeExt; // 6 uimsbf
	}
	return audioObjectType;
}

ISO/IEC 14496-3, 1.5.1.1 Audio object type definition

ID	Type
0	Null
1	AAC main
2	AAC LC
3	AAC SSR
4	AAC LTP
5	SSR
...	...

ISO/IEC 14496-3, 1.6.3.4 samplingFrequencyIndex

index	value
0x0	96000
0x1	88200
0x2	64000
0x3	48000
0x4	44100
0x5	32000
0x6	24000
0x7	22050
0x8	16000
0x9	12000
0xa	11025
0xb	8000
0xc	7350
0xd	reserved
0xe	reserved
0xf	escape value

H.264/AVC

ISO/IEC 14496-15, 5.3.3.1.2 Syntax

aligned(8) class AVCDecoderConfigurationRecord {
	unsigned int(8) configurationVersion = 1;
	unsigned int(8) AVCProfileIndication;
	unsigned int(8) profile_compatibility;
	unsigned int(8) AVCLevelIndication; 
	bit(6) reserved = '111111'b;
	unsigned int(2) lengthSizeMinusOne; 
	bit(3) reserved = '111'b;
	unsigned int(5) numOfSequenceParameterSets;
	for (i = 0; i < numOfSequenceParameterSets; i++) {
		unsigned int(16) sequenceParameterSetLength ;
		bit(8*sequenceParameterSetLength) sequenceParameterSetNALUnit;
	}
	unsigned int(8) numOfPictureParameterSets;
	for (i = 0; i < numOfPictureParameterSets; i++) {
		unsigned int(16) pictureParameterSetLength;
		bit(8*pictureParameterSetLength) pictureParameterSetNALUnit;
	}
	if (profile_idc == 100 || profile_idc == 110 ||
	    profile_idc == 122 || profile_idc == 144)
	{
		bit(6) reserved = '111111'b;
		unsigned int(2) chroma_format;
		bit(5) reserved = '11111'b;
		unsigned int(3) bit_depth_luma_minus8;
		bit(5) reserved = '11111'b;
		unsigned int(3) bit_depth_chroma_minus8;
		unsigned int(8) numOfSequenceParameterSetExt;
		for (i = 0; i < numOfSequenceParameterSetExt; i++) {
			unsigned int(16) sequenceParameterSetExtLength;
			bit(8*sequenceParameterSetExtLength) sequenceParameterSetExtNALUnit;
		}
	}
}

ITU-T H.264(ISO/IEC 14496-10), A.2 Profiles

idc	Profile
66	Baseline
77	Main
88	Extended
100	High
110	High 10
122	High 4:2:2
144	(High 4:4:4; removed)
244	High 4:4:4 Predictive

ITU-T H.264(ISO/IEC 14496-10), A.3 Levels

Defined level_idc: 10, 9¹, 11, 12, 13, 20, 21, 22, 30, 31, 32, 40, 41, 42, 50, 51, 52

H.265/HEVC

ISO/IEC 14496-15, 8.3.3.1.2 Syntax

aligned(8) class HEVCDecoderConfigurationRecord {
	unsigned int(8) configurationVersion = 1;
	unsigned int(2) general_profile_space;
	unsigned int(1) general_tier_flag;
	unsigned int(5) general_profile_idc;
	unsigned int(32) general_profile_compatibility_flags;
	unsigned int(48) general_constraint_indicator_flags;
	unsigned int(8) general_level_idc;
	bit(4) reserved = ‘1111’b;
	unsigned int(12) min_spatial_segmentation_idc;
	bit(6) reserved = ‘111111’b;
	unsigned int(2) parallelismType;
	bit(6) reserved = ‘111111’b;
	unsigned int(2) chromaFormat;
	bit(5) reserved = ‘11111’b;
	unsigned int(3) bitDepthLumaMinus8;
	bit(5) reserved = ‘11111’b;
	unsigned int(3) bitDepthChromaMinus8;
	bit(16) avgFrameRate;
	bit(2) constantFrameRate;
	bit(3) numTemporalLayers;
	bit(1) temporalIdNested;
	unsigned int(2) lengthSizeMinusOne; 
	unsigned int(8) numOfArrays;
	for (j=0; j < numOfArrays; j++) {
		bit(1) array_completeness;
		unsigned int(1) reserved = 0;
		unsigned int(6) NAL_unit_type;
		unsigned int(16) numNalus;
		for (i=0; i< numNalus; i++) {
			unsigned int(16) nalUnitLength;
			bit(8*nalUnitLength) nalUnit;
		}
	}
}

ITU-T H.265(ISO/IEC 23008-2), A.3 Profiles

idc	Profile
1	Main
2	Main 10
3	Main Still Picture

ITU-T H.265(ISO/IEC 23008-2), A.4 Tiers and levels

flag	Tier
0	Main
1	High

idc	Level
30	1
60	2
63	2.1
90	3
93	3.1
120	4
123	4.1
150	5
153	5.1
156	5.2
180	6
183	6.1
186	6.2

Footnotes

1. level_idc==9 represents "Leve 1b" unless Baseline(Constrained Baseline), Main, or Extended profiles. ↩