CAE Project Format

Note: this is internal information, project format may change at any time.

The CAE raw project json format is based on the EAO project format (currently it is more or less equal to it).

Project.json and CAE container

A raw CAE project is a JSON formatted file describing the used essences, the timeline (sequence) and other metadata.

Example:

JS

{
    "EAO": {
        "Comment": "",
        "Text": "",
        "Duration": 60000,
        "LastChange": {
            "User": "Unknown",
            "Date": 1657088850613
        },
		"Files": [
			...
		],
		"Media": [
			...
		],
		"Sequence": {
			"Tracks": [
				...
			],
			"Markers": [
				...
			],
			"Groups": [
				...
			]
		},
		CustomData: {
		}
	}
}

The raw CAE project.json file together will locally created content is stored inside a CAE container file with file extension .cae (also often called a CAE project). A CAE container file is a zip file of the following structure:

project.json
audio sub folder containing locally created content, referenced in project.json

Example:

CODE

project.json
audio
    82b5ea20-2dbe-4306-b1e6-a5abb2dd105b

Top-level entities

Property	Description
Comment	MKL? Free text?
Text	MKL? Is this something like a title?
Duration	MKL? Which duration is this? Sequence duration?
LastChange	MKL? Stored in UTC or local time?
Files	An essence file can be... a DigaSystem URL reference (Filename property starts with http:// or https://) a locally created content (Filename property starts with blob:) something that has to be recreated (Filename property is empty)
Media	A medium description has a one-to-one relationship to a file? A medium description additionally contains Clips and TranscriptionData.
Sequence
CustomData

Files

Property	Description
Filename	a DigaSystem URL reference starting with http:// or https:// a locally created content starting with blob: empty = something that has to be recreated on loading
Format	e.g. Linear, Peakfile, Transcript
FileType	e.g. WAV, WAVEFORM, S2T
Duration	in milliseconds
MediumIdRef	Reference to a medium in Media
SampleRate
SampleCount

Example:

JS

"Files": [{
                "Filename": "https://dpe-demo.davidsystems.com/DpeWebApplication/Media.ashx?tableid=DigaSystem\\playground&entryid=17",
                "Format": "Linear",
                "FileType": "WAV",
                "Duration": 55379,
                "MediumIdRef": "226cc802-60c0-44f9-b131-c6fd743dcfae",
                "SampleRate": 44100,
                "SampleCount": 2442239.2575000003
            }, {
                "Filename": "",
                "Format": "Peakfile",
                "FileType": "WAVEFORM",
                "Duration": 55379,
                "MediumIdRef": "226cc802-60c0-44f9-b131-c6fd743dcfae",
                "SampleRate": 44100,
                "SampleCount": 2442239.2575000003
            }, {
                "Filename": "",
                "Format": "Transcript",
                "FileType": "S2T",
                "Duration": 0,
                "MediumIdRef": "226cc802-60c0-44f9-b131-c6fd743dcfae",
                "SampleRate": 0,
                "SampleCount": 0
            }, {
                "Filename": "blob:https://demo-cae-latest.davidsystems.com/8b9db916-0524-457d-8b3e-2946cdead3ef",
                "Format": "Linear",
                "FileType": "WAV",
                "Duration": 3000,
                "MediumIdRef": "82b5ea20-2dbe-4306-b1e6-a5abb2dd105b",
                "SampleRate": 44100,
                "SampleCount": 132301
            }, {
                "Filename": "",
                "Format": "Peakfile",
                "FileType": "WAVEFORM",
                "Duration": 3000,
                "MediumIdRef": "82b5ea20-2dbe-4306-b1e6-a5abb2dd105b",
                "SampleRate": 44100,
                "SampleCount": 132301
            }
        ]

Media

Property	Description
MediumId	One-to-one relationship to a file
Clips	Clips
TranscriptData	Transcription data

Example:

JS

        "Media": [{
                "MediumId": "226cc802-60c0-44f9-b131-c6fd743dcfae",
                "Clips": [{
                        "Title": "Clip created from file import",
                        "Id": "0eeafbea-fe2e-4bf3-9e98-d3af4108da37",
                        "StartPosition": 0,
                        "Duration": 55379,
                        "Comment": "",
                        "Markers": []
                    }
                ],
                "TranscriptData": {
					...
                }
            }, {
                "MediumId": "82b5ea20-2dbe-4306-b1e6-a5abb2dd105b",
                "Clips": [{
                        "Title": "Clip created from file import",
                        "Id": "6af746d7-117d-4bba-9050-794be15073bb",
                        "StartPosition": 0,
                        "Duration": 3000,
                        "Comment": "",
                        "Markers": []
                    }
                ]
            }

Clips

Clips allow to specify which part of a medium should be used.

Clips are the entities that are referenced from TrackElements.

Property	Description
Title	Clip title
Id	Unique identifier referenced from a TrackElement
StartPosition	Start position (offset) inside its medium
Duration	Duration inside its medium
Comment	Clip comment
Markers	MKL? Is this used? How do they relate to Markers on top-level sequence?

TranscriptData

Sequence

Property	Description
Tracks	Array of tracks
Markers	Array of markers
Groups	MKL?

Tracks

Property	Description
TrackName	Track name
TrackElements	Array of track elements
Muted	true/false
Placeholders	MKL? What is this?
Locked	true/false
Color	MKL? which formats are supported? Example: #1879c7

TrackElements

Property	Description
Id	Unique identifier
RefId	Reference to Clip
Position	Offset on track
Label
Comment
Gain	Example: 1
Locked	true/false
Color	MKL? which formats are supported? Example: #1879c7
FadeIn
FadeOut
GainAutomation	MKL?
TrackElementTranscript	MKL?

Markers

Groups

How do Files, Media, Clips, Tracks and TrackElements relate to each other?

Files and Media

There is a one-to-one relationship between a File (property MediumIdRef) and a Medium (property MediumId)
A file contains information about the essence, e.g. where is it stored and what kind of essence is it
A medium adds the ability to define clips (parts of a file) and transcription data

Tracks, TrackElements and Clips

Tracks contain TrackElements
The TrackElement property Position specifies the offset on the track
The TrackElement property RefId references a Clip
The Clip is part of a Medium
The Clip properties StartPosition and Duration specify the part of the medium that is used
The Medium is linked to a File by the File property MediumIdRef

Sequence => Track => TrackElement => Clip => Medium => File