Ravnur C2PA Implementation

A JavaScript library that helps to implement a client for C2PA manifest validation.

C2PA is an open technical standard providing publishers, creators, and consumers the ability to trace the origin of different types of media. https://c2pa.org/public-draft/

Get Started

1. Import c2pa dependency in your package.json.
2. Create C2PA object instance: c2pa = new C2PA(manifestValidationCallback);
3. Invoke c2pa.initSegment(initSegment); to validate the init segment.
4. Invoke c2pa.validateSegment(dataSegment, validationCallback); to validate the data segment.

Examples

Integration with HLS.js

Create HLS object and setup it according to your needs:

let hls = new Hls(/* parameters */);

Create C2PA object, pass the validation callback as a parameter:

let c2pa = new C2PA((validationResult, manifestData) => {
    if (validationResult == ValidationResult.Complete) {
        alert("c2pa manifest validation complete!");
    }

    if (validationResult == ValidationResult.NoData) {
        alert("c2pa manifest was not found!");
    }

    if (validationResult == ValidationResult.Failed) {
        alert("c2pa manifest validation failed!");
    }
});

Subscribe to HLS event to validate the init segment:

hls.on(Hls.Events.FRAG_PARSING_INIT_SEGMENT, (eventName, initSegmentData) => {
    c2pa.initSegment(initSegmentData);
});

Subscribe to HLS event to validate data segments:

hls.on(Hls.Events.FRAG_PARSING_DATA, (eventName, segmentData) => {
    c2pa.validateSegment(segmentData, validationResult => {
        alert("Data segment is validated!");
    });
});

API Description

C2PA object provides methods for validating the c2pa manifest, validating the data segments and reporting the result.

C2PA( manifestValidationCallback )

The object consturctor accepts validation callback, that invoked after the validation of the c2pa manifest.

manifestValidationCallback: (validationResult, manifestData) => { }

validationResult: ValidationResult // The value from the ValidationResult enum: 'Succeed', 'Failed' or 'NoData'

manifestData: [{
    name: string, // Name of the manifest
    valid: bool // Validation result
}, ...]

initSegment( initSegmentData )

This method completes validation of the init segment.

initSegmentData: {
    tracks {
        video: {
            initSegment: ArrayBuffer // Raw bytes of the video track init segment
        },
        audio: {
            initSegment: ArrayBuffer // Raw bytes of the audio track init segment
        },
        ...
    }
}

validateSegment( dataSegment, validationCallback)

This method completes validation of the video segment.

dataSegment: {
    type: string, // 'video' or 'audio' segment
    frag: {
        start: number, // 0-based offset of the segment start time second
        duration: number, // duration of the segment in seconds
    },
    data1: ArrayBuffer // Raw bytes of the data segment
}

validationCallback: validationResult => { }

validationResult = {
    track: string, // 'video' or 'audio' segment
    start: number, // 0-based offset of the segment start time second
    duration: number, // duration of the segment in seconds
    valid: bool // whether validation succeed
}