Sony .mp4s contain a <?xml...> packet stored in a Meta > XML subdirectory, whose contents Exiftool displays as tags in family 0 and family 1 as group "XML".
I can't find any documentation at exiftool.org or other sites about this. Questions:
1. The syntax is standard XML, but are the contents defined by an industry standard, or are they Sony proprietary?
2. Is this <?xml...> packet what is referred to in the Exiftool documentation as the XML tag (tagid 'xml') in the QuickTime Meta Tags:
https://exiftool.org/TagNames/QuickTime.html ?
That XML tag refers to XMP XML Tags:
https://exiftool.org/TagNames/XMP.html#XML
which refers to XMP dc tags:
https://exiftool.org/TagNames/XMP.html#dc
which doesn't seem related at all to the contents of the <?xml...> packet, so I'm very confused.
An example of the packet and Exiftool's output:
<?xml version="1.0" encoding="UTF-8"?>
<NonRealTimeMeta xmlns="urn:schemas-professionalDisc:nonRealTimeMeta:ver.2.00" xmlns:lib="urn:schemas-professionalDisc:lib:ver.2.00" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" lastUpdate="2021-12-26T09:56:58-06:00">
<TargetMaterial umidRef="060A2B340101010501010D43130000000C78206A749505CF009D6BFFFEB03E97"/>
<Duration value="225"/>
<LtcChangeTable tcFps="30" halfStep="false">
<LtcChange frameCount="0" value="67155600" status="increment"/>
<LtcChange frameCount="224" value="51235600" status="end"/>
</LtcChangeTable>
<CreationDate value="2021-12-26T09:56:58-06:00"/>
<VideoFormat>
<VideoRecPort port="DIRECT"/>
<VideoFrame videoCodec="AVC_1920_1080_HP@L41" captureFps="29.97p" formatFps="29.97p"/>
<VideoLayout pixel="1920" numOfVerticalLine="1080" aspectRatio="16:9"/>
</VideoFormat>
<AudioFormat numOfChannel="2">
<AudioRecPort port="DIRECT" audioCodec="LPCM16" trackDst="CH1"/>
<AudioRecPort port="DIRECT" audioCodec="LPCM16" trackDst="CH2"/>
</AudioFormat>
<Device manufacturer="Sony" modelName="ILCE-7M3" serialNo="4294967295"/>
<RecordingMode type="normal" cacheRec="false"/>
<AcquisitionRecord>
<Group name="CameraUnitMetadataSet">
<Item name="CaptureGammaEquation" value="rec709-xvycc"/>
<Item name="CaptureColorPrimaries" value="rec709"/>
<Item name="CodingEquations" value="rec709"/>
</Group>
<Group name="ExifGPS">
<Item name="VersionID" value="2.2.0.0"/>
<Item name="Status" value="V"/>
<Item name="MapDatum" value="WGS-84"/>
<Item name="Differential" value="0"/>
</Group>
</AcquisitionRecord>
</NonRealTimeMeta>
$ exiftool -a -G0 -xml:all *.MP4
[XML] Last Update : 2021:12:26 09:56:58-06:00
[XML] Target Material Umid Ref : 060A2B340101010501010D43130000000C78206A749505CF009D6BFFFEB03E97
[XML] Duration Value : 225
[XML] Ltc Change Table Tc Fps : 30
[XML] Ltc Change Table Half Step : false
[XML] Ltc Change Table Ltc Change Frame Count: 0
[XML] Ltc Change Table Ltc Change Value: 67155600
[XML] Ltc Change Table Ltc Change Status: increment
[XML] Ltc Change Table Ltc Change Frame Count: 224
[XML] Ltc Change Table Ltc Change Value: 51235600
[XML] Ltc Change Table Ltc Change Status: end
[XML] Creation Date Value : 2021:12:26 09:56:58-06:00
[XML] Video Format Video Rec Port Port: DIRECT
[XML] Video Format Video Frame Video Codec: AVC_1920_1080_HP@L41
[XML] Video Format Video Frame Capture Fps: 29.97p
[XML] Video Format Video Frame Format Fps: 29.97p
[XML] Video Format Video Layout Pixel : 1920
[XML] Video Format Video Layout Num Of Vertical Line: 1080
[XML] Video Format Video Layout Aspect Ratio: 16:9
[XML] Audio Format Num Of Channel : 2
[XML] Audio Format Audio Rec Port Port: DIRECT
[XML] Audio Format Audio Rec Port Audio Codec: LPCM16
[XML] Audio Format Audio Rec Port Track Dst: CH1
[XML] Audio Format Audio Rec Port Port: DIRECT
[XML] Audio Format Audio Rec Port Audio Codec: LPCM16
[XML] Audio Format Audio Rec Port Track Dst: CH2
[XML] Device Manufacturer : Sony
[XML] Device Model Name : ILCE-7M3
[XML] Device Serial No : 4294967295
[XML] Recording Mode Type : normal
[XML] Recording Mode Cache Rec : false
[XML] Acquisition Record Group Name : CameraUnitMetadataSet
[XML] Acquisition Record Group Item Name: CaptureGammaEquation
[XML] Acquisition Record Group Item Value: rec709-xvycc
[XML] Acquisition Record Group Item Name: CaptureColorPrimaries
[XML] Acquisition Record Group Item Value: rec709
[XML] Acquisition Record Group Item Name: CodingEquations
[XML] Acquisition Record Group Item Value: rec709
[XML] Acquisition Record Group Name : ExifGPS
[XML] Acquisition Record Group Item Name: VersionID
[XML] Acquisition Record Group Item Value: 2.2.0.0
[XML] Acquisition Record Group Item Name: Status
[XML] Acquisition Record Group Item Value: V
[XML] Acquisition Record Group Item Name: MapDatum
[XML] Acquisition Record Group Item Value: WGS-84
[XML] Acquisition Record Group Item Name: Differential
[XML] Acquisition Record Group Item Value: 0
Most likely proprietary Sony data. If you Google search on professionalDisc:nonRealTimeMeta or professionalDisc:lib, you'll find a fair amount of links.
QuoteIf you Google search on professionalDisc:nonRealTimeMeta or professionalDisc:lib, you'll find a fair amount of links.
I already did that, and I didn't see anything remotely authoritative, just people struggling to understand what they were seeing.
ExifTool really doesn't pre-define any XML tags. The dc tags are an exception because they are used in multiple XML schemas.
XML is basically a free-for-all as far as I can tell. Some schemas are published, but many are not.
- Phil
"ExifTool really doesn't pre-define any XML tags. The dc tags are an exception because they are used in multiple XML schemas."
Thanks for the details, that removes some of my confusion.