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Unified Diff: webrtc/modules/audio_coding/codecs/opus/opus/src/doc/opus_in_isobmff.html

Issue 1612443002: Create local copy of Opus v1.1.2 Base URL: https://chromium.googlesource.com/external/webrtc.git@master
Patch Set: testing if neteq4_opus_network_stats.dat.sha1 needs to be updated Created 4 years, 11 months ago
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+<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN" "http://www.w3.org/TR/html4/strict.dtd">
+<html>
+ <head>
+ <link rel="stylesheet" type="text/css" href="opus_in_isobmff.css"/>
+ <meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
+ <title>Encapsulation of Opus in ISO Base Media File Format</title>
+ </head>
+ <body bgcolor="0x333333" text="#60B0C0">
+ <b><u>Encapsulation of Opus in ISO Base Media File Format</u></b><br>
+ <font size="2">last updated: January 12, 2015</font><br>
+ <br>
+ <div class="normal_link pre frame_box">
+
+ Encapsulation of Opus in ISO Base Media File Format
+ Version 0.6.6 (incomplete)
+
+
+Table of Contents
+<a href="#1">1</a> Scope
+<a href="#2">2</a> Normative References
+<a href="#3">3</a> Terms and Definitions
+<a href="#4">4</a> Design Rules of Encapsulation
+ <a href="#4.1">4.1</a> File Type Indentification
+ <a href="#4.2">4.2</a> Overview of Track Structure
+ <a href="#4.3">4.3</a> Definitions of Opus sample
+ <a href="#4.3.1">4.3.1</a> Sample entry format
+ <a href="#4.3.2">4.3.2</a> Opus Specific Box
+ <a href="#4.3.3">4.3.3</a> Sample format
+ <a href="#4.3.4">4.3.4</a> Duration of Opus sample
+ <a href="#4.3.5">4.3.5</a> Sub-sample
+ <a href="#4.3.6">4.3.6</a> Random Access
+ <a href="#4.3.6.1">4.3.6.1</a> Random Access Point
+ <a href="#4.3.6.2">4.3.6.2</a> Pre-roll
+ <a href="#4.4">4.4</a> Trimming of Actual Duration
+ <a href="#4.5">4.5</a> Channel Layout (informative)
+ <a href="#4.6">4.6</a> Basic Structure (informative)
+ <a href="#4.6.1">4.6.2</a> Initial Movie
+ <a href="#4.6.2">4.6.3</a> Movie Fragments
+ <a href="#4.7">4.7</a> Example of Encapsulation (informative)
+<a href="#5">5</a> Author's Address
+
+<a name="1"></a>
+1 Scope
+ This specification specifies the fundamental way of the encapsulation of Opus coded bitstreams in ISO Base Media
+ file format and its derivatives. The encapsulation of Opus coded bitstreams in QuickTime file format is outside
+ the scope of this specification.
+
+<a name="2"></a>
+2 Normative References
+ [1] ISO/IEC 14496-12:2012 Corrected version
+ Information technology — Coding of audio-visual objects — Part 12: ISO base media file format
+
+ [2] ISO/IEC 14496-12:2012/Amd.1:2013
+ Information technology — Coding of audio-visual objects — Part 12: ISO base media file format
+ AMENDMENT 1: Various enhancements including support for large metadata
+
+ [3] RFC 6716
+ Definition of the Opus Audio Codec
+
+ [4] draft-ietf-codec-oggopus-06
+ Ogg Encapsulation for the Opus Audio Codec
+
+<a name="3"></a>
+3 Terms and Definitions
+ 3.1 active track
+ enabled track from the non-alternate group or selected track from alternate group
+
+ 3.2 actual duration
+ duration constructed from valid samples
+
+ 3.3 edit
+ entry in the Edit List Box
+
+ 3.4 padded samples
+ PCM samples after decoding Opus sample(s) which are not valid samples
+ An Opus bitstream always contains them partially at the beginning and may contain them in part at the end, as
+ long as not physically removed yet at the beginning and/or the end.
+
+ 3.5 priming samples
+ padded samples at the beginning of the Opus bitstream
+
+ 3.6 sample-accurate
+ for any PCM sample, a timestamp exactly matching its sampling timestamp is present in the media timeline.
+
+ 3.7 valid samples
+ PCM samples after decoding Opus sample(s) corresponding to input PCM samples
+
+<a name="4"></a>
+4 Design Rules of Encapsulation
+ 4.1 File Type Indentification<a name="4.1"></a>
+ This specification does not define any brand to declare files are conformant to this specification. However,
+ files conformant to this specification shall contain at least one brand, which supports the requirements and the
+ requirements described in this clause without contradiction, in the compatible brands list of the File Type Box.
+ As an example, the minimal support of the encapsulation of Opus bitstreams in ISO Base Media file format requires
+ the 'iso2' brand in the compatible brands list since support of roll groups is required.
+<a name="4.2"></a>
+ 4.2 Overview of Track Structure
+ This clause summarizes requirements of the encapsulation of Opus coded bitstream as media data in audio tracks
+ in file formats compliant with the ISO Base Media File Format. The details are described in clauses after this
+ clause.
+ + The handler_type field in the Handler Reference Box shall be set to 'soun'.
+ + The Media Information Box shall contain the Sound Media Header Box.
+ + The codingname of the sample entry is 'Opus'.
+ This specification does not define any encapsulation using MP4AudioSampleEntry with objectTypeIndication
+ specified by the MPEG-4 Registration Authority (http://www.mp4ra.org/).
+ See 4.3.1 Sample entry format to get the details about the sample entry.
+ + The 'dOps' box is added to the sample entry to convey initializing information for the decoder.
+ See 4.3.2 Opus Specific Box to get the details.
+ + An Opus sample is exactly one Opus packet for each of different Opus bitstreams.
+ See 4.3.3 Sample format to get the details.
+ + Every Opus sample is a sync sample but requires pre-roll for every random access to get correct output.
+ See 4.3.6 Random Access to get the details.
+<a name="4.3"></a>
+ 4.3 Definitions of Opus sample
+ 4.3.1 Sample entry format<a name="4.3.1"></a>
+ For any track containing Opus bitstreams, at least one sample entry describing corresponding Opus bitstream
+ shall be present inside the Sample Table Box. This version of the specification defines only one sample
+ entry format named OpusSampleEntry whose codingname is 'Opus'. This sample entry includes exactly one Opus
+ Specific Box defined in 4.3.2 as a mandatory box and indicates that Opus samples described by this sample
+ entry are stored by the sample format described in 4.3.3.
+
+ The syntax and semantics of the OpusSampleEntry is shown as follows.
+
+ class OpusSampleEntry() extends AudioSampleEntry ('Opus'){
+ OpusSpecificBox();
+ }
+
+ + channelcount:
+ The channelcount field shall be set to the sum of the total number of Opus bitstreams and the number
+ of Opus bitstreams producing two channels. This value is indentical with (M+N), where M is the value of
+ the *Coupled Stream Count* field and N is the value of the *Stream Count* field in the *Channel Mapping
+ Table* in the identification header defined in Ogg Opus [4].
+ + samplesize:
+ The samplesize field shall be set to 16.
+ + samplerate:
+ The samplerate field shall be set to 48000&lt&lt16.
+ + OpusSpecificBox
+ This box contains initializing information for the decoder as defined in 4.3.2.
+
+ 4.3.2 Opus Specific Box<a name="4.3.2"></a>
+ Exactly one Opus Specific Box shall be present in each OpusSampleEntry.
+ The Opus Specific Box contains the Version field and this specification defines version 0 of this box.
+ If incompatible changes occured in the fields after the Version field within the OpusSpecificBox in the
+ future versions of this specification, another version will be defined.
+ This box refers to Ogg Opus [4] at many parts but all the data are stored as big-endian format.
+
+ The syntax and semantics of the Opus Specific Box is shown as follows.
+
+ class ChannelMappingTable (unsigned int(8) OutputChannelCount){
+ unsigned int(8) StreamCount;
+ unsigned int(8) CoupledCount;
+ unsigned int(8 * OutputChannelCount) ChannelMapping;
+ }
+
+ aligned(8) class OpusSpecificBox extends Box('dOps'){
+ unsigned int(8) Version;
+ unsigned int(8) OutputChannelCount;
+ unsigned int(16) PreSkip;
+ unsigned int(32) InputSampleRate;
+ signed int(16) OutputGain;
+ unsigned int(8) ChannelMappingFamily;
+ if (ChannelMappingFamily != 0) {
+ ChannelMappingTable(OutputChannelCount);
+ }
+ }
+
+ + Version:
+ The Version field shall be set to 0.
+ In the future versions of this specification, this field may be set to other values. And without support
+ of those values, the reader shall not read the fields after this within the OpusSpecificBox.
+ + OutputChannelCount:
+ The OutputChannelCount field shall be set to the same value as the *Output Channel Count* field in the
+ identification header defined in Ogg Opus [4].
+ + PreSkip:
+ The PreSkip field indicates the number of the priming samples, that is, the number of samples at 48000 Hz
+ to discard from the decoder output when starting playback. The value of the PreSkip field could be zero
+ when removing Opus samples containing the number of PCM samples equal to or more than of the priming
+ samples. The PreSkip field is not used for discarding the priming samples at the whole playback at all
+ since it is informative only, and that task falls on the Edit List Box.
+ + InputSampleRate:
+ The InputSampleRate field shall be set to the same value as the *Input Sample Rate* field in the
+ identification header defined in Ogg Opus [4].
+ + OutputGain:
+ The OutputGain field shall be set to the same value as the *Output Gain* field in the identification
+ header define in Ogg Opus [4]. Note that the value is stored as 8.8 fixed-point.
+ + ChannelMappingFamily:
+ The ChannelMappingFamily field shall be set to the same value as the *Channel Mapping Family* field in
+ the identification header defined in Ogg Opus [4].
+ + StreamCount:
+ The StreamCount field shall be set to the same value as the *Stream Count* field in the identification
+ header defined in Ogg Opus [4].
+ + CoupledCount:
+ The CoupledCount field shall be set to the same value as the *Coupled Count* field in the identification
+ header defined in Ogg Opus [4].
+ + ChannelMapping:
+ The ChannelMapping field shall be set to the same octet string as *Channel Mapping* field in the identi-
+ fication header defined in Ogg Opus [4].
+
+ 4.3.3 Sample format<a name="4.3.3"></a>
+ An Opus sample is exactly one Opus packet for each of different Opus bitstreams. Due to support more than
+ two channels, an Opus sample can contain frames from multiple Opus bitstreams but all Opus packets shall
+ share with the total of frame sizes in a single Opus sample. The way of how to pack an Opus packet from
+ each of Opus bitstreams into a single Opus sample follows Appendix B. in RFC 6716 [3].
+ The endianness has nothing to do with any Opus sample since every Opus packet is processed byte-by-byte.
+ In this specification, 'sample' means 'Opus sample' except for 'padded samples', 'priming samples', 'valid
+ sample' and 'sample-accurate', i.e. 'sample' is 'sample' in the term defined in ISO/IEC 14496-12 [1].
+
+ +-----------------------------------------+-------------------------------------+
+ | Opus packet 0 (self-delimiting framing) | Opus packet 1 (undelimited framing) |
+ +-----------------------------------------+-------------------------------------+
+ |<---------------------------- the size of Opus sample ------------------------>|
+
+ Figure 1 - Example structure of an Opus sample containing two Opus bitstreams
+
+ 4.3.4 Duration of Opus sample<a name="4.3.4"></a>
+ The duration of Opus sample is given by multiplying the total of frame sizes for a single Opus bitstream
+ expressed in seconds by the value of the timescale field in the Media Header Box.
+ Let's say an Opus sample consists of two Opus bitstreams, where the frame size of one bitstream is 40 milli-
+ seconds and the frame size of another is 60 milliseconds, and the timescale field in the Media Header Box
+ is set to 48000, then the duration of that Opus sample shall be 120 milliseconds since three 40 millisecond
+ frame and two 60 millisecond frames shall be contained because of the maximum duration of Opus packet, 120
+ milliseconds, and 5760 in the timescale indicated in the Media Header Box.
+
+ To indicate the valid samples excluding the padded samples at the end of Opus bitstream, the duration of
+ the last Opus sample of an Opus bitstream is given by multiplying the number of the valid samples by the
+ value produced by dividing the value of the timescale field in the Media Header Box by 48000.
+
+ 4.3.5 Sub-sample<a name="4.3.5"></a>
+ The structure of the last Opus packet in an Opus sample is different from the others in the same Opus sample,
+ and the others are invalid Opus packets as an Opus sample because of self-delimiting framing. To avoid
+ complexities, sub-sample is not defined for Opus sample in this specification.
+
+ 4.3.6 Random Access<a name="4.3.6"></a>
+ This subclause describes the nature of the random access of Opus sample.
+
+ 4.3.6.1 Random Access Point<a name="4.3.6.1"></a>
+ All Opus samples can be independently decoded i.e. every Opus sample is a sync sample. Therefore, the
+ Sync Sample Box shall not be present as long as there are no samples other than Opus samples in the same
+ track. And the sample_is_non_sync_sample field for Opus samples shall be set to 0.
+
+ 4.3.6.2 Pre-roll<a name="4.3.6.2"></a>
+ Opus bitstream requires at least 80 millisecond pre-roll after each random access to get correct output.
+ Pre-roll is indicated by the roll_distance field in AudioRollRecoveryEntry. AudioPreRollEntry shall not
+ be used since every Opus sample is a sync sample in Opus bitstream. Note that roll_distance is expressed
+ in sample units in a term of ISO Base Media File Format, and always takes negative values.
+
+ For any track containing Opus bitstreams, at least one Sample Group Description Box and at least one
+ Sample to Group Box within the Sample Table Box shall be present and these have the grouping_type field
+ set to 'roll'. If any Opus sample is contained in a track fragment, the Sample to Group Box with the
+ grouping_type field set to 'roll' shall be present for that track fragment.
+
+ For the requirement of AudioRollRecoveryEntry, the compatible_brands field in the File Type Box shall
+ contain at least one brand which requires support for roll groups.
+<a name="4.4"></a>
+ 4.4 Trimming of Actual Duration
+ Due to the priming samples (or the padding at the beginning) derived from the pre-roll for the startup and the
+ padded samples at the end, we need trim from media to get the actual duration. An edit in the Edit List Box can
+ achieve this demand, and the Edit Box and the Edit List Box shall be present.
+
+ For sample-accurate trimming, proper timescale should be set to the timescale field in the Movie Header Box
+ and the Media Header Box inside Track Box(es) for Opus bitstream. The timescale field in the Media Header Box is
+ typically set to 48000. It is recommended that the timescale field in the Movie Header Box be set to the same
+ value of the timescale field in the Media Header Box in order to avoid the rounding problem when specifying
+ duration of edit if the timescales in all of the Media Header Boxes are set to the same value.
+
+ For example, to indicate the actual duration of an Opus bitstream in a track with the timescale fields of both
+ the Movie Header Box and the Media Header Box set to 48000, we would use the following edit:
+ segment_duration = the number of the valid samples
+ media_time = the number of the priming samples
+ media_rate = 1 &lt&lt 16
+
+ The Edit List Box is applied to whole movie including all movie fragments. Therefore, it is impossible to tell
+ the actual duration in the case producing movie fragments on the fly such as live-streaming. In such cases,
+ the duration of the last Opus sample may be helpful by setting zero to the segment_duration field since the
+ value 0 represents implicit duration equal to the sum of the duration of all samples.
+<a name="4.5"></a>
+ 4.5 Channel Layout (informative)
+ By the application of alternate_group in the Track Header Box, whole audio channels in all active tracks from
+ non-alternate group and/or different alternate group from each other are composited into the presentation. If
+ an Opus sample consists of multiple Opus bitstreams, it can be splitted into individual Opus bitstreams and
+ reconstructed into new Opus samples as long as every Opus bitstream has the same total duration in each Opus
+ sample. This nature can be utilized to encapsulate a single Opus bitstream in each track without breaking the
+ original channel layout.
+
+ As an example, let's say there is a following track:
+ OutputChannelCount = 6;
+ StreamCount = 4;
+ CoupledCount = 2;
+ ChannelMapping = {0, 4, 1, 2, 3, 5}; // front left, front center, front right, rear left, rear right, LFE
+ Here, to couple front left to front right channels into the first stream, and couple rear left to rear right
+ channels into the second stream, reordering is needed since coupled streams must precede any non-coupled stream.
+ You extract the four Opus bitstreams from this track and you encapsulate two of the four into a track and the
+ others into another track. The former track is as follows.
+ OutputChannelCount = 6;
+ StreamCount = 2;
+ CoupledCount = 2;
+ ChannelMapping = {0, 255, 1, 2, 3, 255}; // front left, front center, front right, rear left, rear right, LFE
+ And the latter track is as follows.
+ OutputChannelCount = 6;
+ StreamCount = 2;
+ CoupledCount = 0;
+ ChannelMapping = {255, 0, 255, 255, 255, 1}; // front left, front center, front right, rear left, rear right, LFE
+ In addition, the value of the alternate_group field in the both tracks is set to 0. As the result, the player
+ may play as if channels with 255 are not present, and play the presentation constructed from the both tracks
+ in the same channel layout as the one of the original track. Keep in mind that the way of the composition, i.e.
+ the mixing for playback, is not defined here, and maybe different results could occur except for the channel
+ layout of the original, depending on an implementation or the definition of a derived file format.
+
+ Note that some derived file formats may specify the restriction to ignore alternate grouping. In the context of
+ such file formats, this application is not available. This unavailability does not mean incompatibilities among
+ file formats unless the restriction to the value of the alternate_group field is specified and brings about
+ any conflict among their definitions.
+<a name="4.6"></a>
+ 4.6 Basic Structure (informative)
+ 4.6.1 Initial Movie<a name="4.6.1"></a>
+ This subclause shows a basic structure of the Movie Box as follows:
+
+ +----+----+----+----+----+----+----+----+------------------------------+
+ |moov| | | | | | | | Movie Box |
+ +----+----+----+----+----+----+----+----+------------------------------+
+ | |mvhd| | | | | | | Movie Header Box |
+ +----+----+----+----+----+----+----+----+------------------------------+
+ | |trak| | | | | | | Track Box |
+ +----+----+----+----+----+----+----+----+------------------------------+
+ | | |tkhd| | | | | | Track Header Box |
+ +----+----+----+----+----+----+----+----+------------------------------+
+ | | |edts| | | | | | Edit Box |
+ +----+----+----+----+----+----+----+----+------------------------------+
+ | | | |elst| | | | | Edit List Box |
+ +----+----+----+----+----+----+----+----+------------------------------+
+ | | |mdia| | | | | | Media Box |
+ +----+----+----+----+----+----+----+----+------------------------------+
+ | | | |mdhd| | | | | Media Header Box |
+ +----+----+----+----+----+----+----+----+------------------------------+
+ | | | |hdlr| | | | | Handler Reference Box |
+ +----+----+----+----+----+----+----+----+------------------------------+
+ | | | |minf| | | | | Media Information Box |
+ +----+----+----+----+----+----+----+----+------------------------------+
+ | | | | |smhd| | | | Sound Media Header Box |
+ +----+----+----+----+----+----+----+----+------------------------------+
+ | | | | |dinf| | | | Data Information Box |
+ +----+----+----+----+----+----+----+----+------------------------------+
+ | | | | | |dref| | | Data Reference Box |
+ +----+----+----+----+----+----+----+----+------------------------------+
+ | | | | | | |url | | DataEntryUrlBox |
+ +----+----+----+----+----+----+ or +----+------------------------------+
+ | | | | | | |urn | | DataEntryUrnBox |
+ +----+----+----+----+----+----+----+----+------------------------------+
+ | | | | |stbl| | | | Sample Table |
+ +----+----+----+----+----+----+----+----+------------------------------+
+ | | | | | |stsd| | | Sample Description Box |
+ +----+----+----+----+----+----+----+----+------------------------------+
+ | | | | | | |Opus| | OpusSampleEntry |
+ +----+----+----+----+----+----+----+----+------------------------------+
+ | | | | | | | |dOps| Opus Specific Box |
+ +----+----+----+----+----+----+----+----+------------------------------+
+ | | | | | |stts| | | Decoding Time to Sample Box |
+ +----+----+----+----+----+----+----+----+------------------------------+
+ | | | | | |stsc| | | Sample To Chunk Box |
+ +----+----+----+----+----+----+----+----+------------------------------+
+ | | | | | |stsz| | | Sample Size Box |
+ +----+----+----+----+----+ or +----+----+------------------------------+
+ | | | | | |stz2| | | Compact Sample Size Box |
+ +----+----+----+----+----+----+----+----+------------------------------+
+ | | | | | |stco| | | Chunk Offset Box |
+ +----+----+----+----+----+ or +----+----+------------------------------+
+ | | | | | |co64| | | Chunk Large Offset Box |
+ +----+----+----+----+----+----+----+----+------------------------------+
+ | | | | | |sgpd| | | Sample Group Description Box |
+ +----+----+----+----+----+----+----+----+------------------------------+
+ | | | | | |sbgp| | | Sample to Group Box |
+ +----+----+----+----+----+----+----+----+------------------------------+
+ | |mvex|* | | | | | | Movie Extends Box |
+ +----+----+----+----+----+----+----+----+------------------------------+
+ | | |trex|* | | | | | Track Extends Box |
+ +----+----+----+----+----+----+----+----+------------------------------+
+
+ Figure 2 - Basic structure of Movie Box
+
+ It is strongly recommended that the order of boxes should follow the above structure.
+ Boxes marked with an asterisk (*) may be present.
+ For most boxes listed above, the definition is as is defined in ISO/IEC 14496-12 [1]. The additional boxes
+ and the additional requirements, restrictions and recommendations to the other boxes are described in this
+ specification.
+
+ 4.6.2 Movie Fragments<a name="4.6.2"></a>
+ This subclause shows a basic structure of the Movie Fragment Box as follows:
+
+ +----+----+----+----+----+----+----+----+------------------------------+
+ |moof| | | | | | | | Movie Fragment Box |
+ +----+----+----+----+----+----+----+----+------------------------------+
+ | |mfhd| | | | | | | Movie Fragment Header Box |
+ +----+----+----+----+----+----+----+----+------------------------------+
+ | |traf| | | | | | | Track Fragment Box |
+ +----+----+----+----+----+----+----+----+------------------------------+
+ | | |tfhd| | | | | | Track Fragment Header Box |
+ +----+----+----+----+----+----+----+----+------------------------------+
+ | | |trun| | | | | | Track Fragment Run Box |
+ +----+----+----+----+----+----+----+----+------------------------------+
+ | | |sgpd|* | | | | | Sample Group Description Box |
+ +----+----+----+----+----+----+----+----+------------------------------+
+ | | |sbgp|* | | | | | Sample to Group Box |
+ +----+----+----+----+----+----+----+----+------------------------------+
+
+ Figure 3 - Basic structure of Movie Fragment Box
+
+ It is strongly recommended that the Movie Fragment Header Box and the Track Fragment Header Box be
+ placed first in their container.
+ Boxes marked with an asterisk (*) may be present.
+ For the boxes listed above, the definition is as is defined in ISO/IEC 14496-12 [1].
+<a name="4.7"></a>
+ 4.7 Example of Encapsulation (informative)
+ [File]
+ size = 17790
+ [ftyp: File Type Box]
+ position = 0
+ size = 24
+ major_brand = mp42 : MP4 version 2
+ minor_version = 0
+ compatible_brands
+ brand[0] = mp42 : MP4 version 2
+ brand[1] = iso2 : ISO Base Media file format version 2
+ [moov: Movie Box]
+ position = 24
+ size = 757
+ [mvhd: Movie Header Box]
+ position = 32
+ size = 108
+ version = 0
+ flags = 0x000000
+ creation_time = UTC 2014/12/12, 18:41:19
+ modification_time = UTC 2014/12/12, 18:41:19
+ timescale = 48000
+ duration = 33600 (00:00:00.700)
+ rate = 1.000000
+ volume = 1.000000
+ reserved = 0x0000
+ reserved = 0x00000000
+ reserved = 0x00000000
+ transformation matrix
+ | a, b, u | | 1.000000, 0.000000, 0.000000 |
+ | c, d, v | = | 0.000000, 1.000000, 0.000000 |
+ | x, y, w | | 0.000000, 0.000000, 1.000000 |
+ pre_defined = 0x00000000
+ pre_defined = 0x00000000
+ pre_defined = 0x00000000
+ pre_defined = 0x00000000
+ pre_defined = 0x00000000
+ pre_defined = 0x00000000
+ next_track_ID = 2
+ [iods: Object Descriptor Box]
+ position = 140
+ size = 33
+ version = 0
+ flags = 0x000000
+ [tag = 0x10: MP4_IOD]
+ expandableClassSize = 16
+ ObjectDescriptorID = 1
+ URL_Flag = 0
+ includeInlineProfileLevelFlag = 0
+ reserved = 0xf
+ ODProfileLevelIndication = 0xff
+ sceneProfileLevelIndication = 0xff
+ audioProfileLevelIndication = 0xfe
+ visualProfileLevelIndication = 0xff
+ graphicsProfileLevelIndication = 0xff
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+ [trak: Track Box]
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+ size = 608
+ [tkhd: Track Header Box]
+ position = 181
+ size = 92
+ version = 0
+ flags = 0x000007
+ Track enabled
+ Track in movie
+ Track in preview
+ creation_time = UTC 2014/12/12, 18:41:19
+ modification_time = UTC 2014/12/12, 18:41:19
+ track_ID = 1
+ reserved = 0x00000000
+ duration = 33600 (00:00:00.700)
+ reserved = 0x00000000
+ reserved = 0x00000000
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+ volume = 1.000000
+ reserved = 0x0000
+ transformation matrix
+ | a, b, u | | 1.000000, 0.000000, 0.000000 |
+ | c, d, v | = | 0.000000, 1.000000, 0.000000 |
+ | x, y, w | | 0.000000, 0.000000, 1.000000 |
+ width = 0.000000
+ height = 0.000000
+ [edts: Edit Box]
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+ size = 36
+ [elst: Edit List Box]
+ position = 281
+ size = 28
+ version = 0
+ flags = 0x000000
+ entry_count = 1
+ entry[0]
+ segment_duration = 33600
+ media_time = 312
+ media_rate = 1.000000
+ [mdia: Media Box]
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+ size = 472
+ [mdhd: Media Header Box]
+ position = 317
+ size = 32
+ version = 0
+ flags = 0x000000
+ creation_time = UTC 2014/12/12, 18:41:19
+ modification_time = UTC 2014/12/12, 18:41:19
+ timescale = 48000
+ duration = 34560 (00:00:00.720)
+ language = und
+ pre_defined = 0x0000
+ [hdlr: Handler Reference Box]
+ position = 349
+ size = 51
+ version = 0
+ flags = 0x000000
+ pre_defined = 0x00000000
+ handler_type = soun
+ reserved = 0x00000000
+ reserved = 0x00000000
+ reserved = 0x00000000
+ name = Xiph Audio Handler
+ [minf: Media Information Box]
+ position = 400
+ size = 381
+ [smhd: Sound Media Header Box]
+ position = 408
+ size = 16
+ version = 0
+ flags = 0x000000
+ balance = 0.000000
+ reserved = 0x0000
+ [dinf: Data Information Box]
+ position = 424
+ size = 36
+ [dref: Data Reference Box]
+ position = 432
+ size = 28
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+ flags = 0x000000
+ entry_count = 1
+ [url : Data Entry Url Box]
+ position = 448
+ size = 12
+ version = 0
+ flags = 0x000001
+ location = in the same file
+ [stbl: Sample Table Box]
+ position = 460
+ size = 321
+ [stsd: Sample Description Box]
+ position = 468
+ size = 79
+ version = 0
+ flags = 0x000000
+ entry_count = 1
+ [Opus: Audio Description]
+ position = 484
+ size = 63
+ reserved = 0x000000000000
+ data_reference_index = 1
+ reserved = 0x0000
+ reserved = 0x0000
+ reserved = 0x00000000
+ channelcount = 6
+ samplesize = 16
+ pre_defined = 0
+ reserved = 0
+ samplerate = 48000.000000
+ [dOps: Opus Specific Box]
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+ size = 27
+ Version = 0
+ OutputChannelCount = 6
+ PreSkip = 312
+ InputSampleRate = 48000
+ OutputGain = 0
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+ StreamCount = 4
+ CoupledCount = 2
+ ChannelMapping
+ 0 -> 0: front left
+ 1 -> 4: fron center
+ 2 -> 1: front right
+ 3 -> 2: side left
+ 4 -> 3: side right
+ 5 -> 5: rear center
+ [stts: Decoding Time to Sample Box]
+ position = 547
+ size = 24
+ version = 0
+ flags = 0x000000
+ entry_count = 1
+ entry[0]
+ sample_count = 18
+ sample_delta = 1920
+ [stsc: Sample To Chunk Box]
+ position = 571
+ size = 40
+ version = 0
+ flags = 0x000000
+ entry_count = 2
+ entry[0]
+ first_chunk = 1
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+ sample_description_index = 1
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+ samples_per_chunk = 5
+ sample_description_index = 1
+ [stsz: Sample Size Box]
+ position = 611
+ size = 92
+ version = 0
+ flags = 0x000000
+ sample_size = 0 (variable)
+ sample_count = 18
+ entry_size[0] = 977
+ entry_size[1] = 938
+ entry_size[2] = 939
+ entry_size[3] = 938
+ entry_size[4] = 934
+ entry_size[5] = 945
+ entry_size[6] = 948
+ entry_size[7] = 956
+ entry_size[8] = 955
+ entry_size[9] = 930
+ entry_size[10] = 933
+ entry_size[11] = 934
+ entry_size[12] = 972
+ entry_size[13] = 977
+ entry_size[14] = 958
+ entry_size[15] = 949
+ entry_size[16] = 962
+ entry_size[17] = 848
+ [stco: Chunk Offset Box]
+ position = 703
+ size = 24
+ version = 0
+ flags = 0x000000
+ entry_count = 2
+ chunk_offset[0] = 797
+ chunk_offset[1] = 13096
+ [sgpd: Sample Group Description Box]
+ position = 727
+ size = 26
+ version = 1
+ flags = 0x000000
+ grouping_type = roll
+ default_length = 2 (constant)
+ entry_count = 1
+ roll_distance[0] = -2
+ [sbgp: Sample to Group Box]
+ position = 753
+ size = 28
+ version = 0
+ flags = 0x000000
+ grouping_type = roll
+ entry_count = 1
+ entry[0]
+ sample_count = 18
+ group_description_index = 1
+ [free: Free Space Box]
+ position = 781
+ size = 8
+ [mdat: Media Data Box]
+ position = 789
+ size = 17001
+<a name="5"></a>
+5 Authors' Address
+ Yusuke Nakamura
+ Email: muken.the.vfrmaniac |at| gmail.com
+ </div>
+ </body>
+</html>
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