Cryptographic provenance metadata about how media was created or edited.
It helps trace origin, but absence of C2PA does not prove a file is fake.
JRC DigComp / EPSOHQ Digital Skills DB
Deep dive
C2PA: cryptographic provenance metadata for media
C2PA adds cryptographic provenance metadata showing how media was created or edited; the exam trap is that missing C2PA does not mean the file is fake.
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var parts = value.trim().split(':');
var seconds = parts.pop() || '0';
var minutes = parts.pop() || '0';
var hours = parts.pop() || '0';
return (Number(hours) * 3600) + (Number(minutes) * 60) + Number(seconds.replace(',', '.'));
};
var parseCues = function(text) {
return text
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var timing = lines.shift() || '';
var parts = timing.split('-->').map(function(part) { return part.trim(); });
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start: parseTimestamp(parts[0] || '0'),
end: parseTimestamp(parts[1] || '0'),
text: lines.join(' '),
};
})
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};
var findCue = function(cues, time) {
return cues.find(function(cue) { return time >= cue.start && time < cue.end; })
|| cues.find(function(cue) { return time < cue.start; })
|| cues[cues.length - 1]
|| null;
};
players.forEach(function(player) {
var audio = player.querySelector('audio');
var output = player.querySelector('[data-audio-captions-output]');
if (!audio || !output) {
return;
}
fetch(player.dataset.captionsUrl)
.then(function(response) { return response.ok ? response.text() : ''; })
.then(function(text) {
var cues = parseCues(text);
var activeText = '';
var render = function() {
var cue = findCue(cues, audio.currentTime);
if (!cue || cue.text === activeText) {
return;
}
activeText = cue.text;
output.textContent = cue.text;
};
render();
audio.addEventListener('timeupdate', render);
audio.addEventListener('seeked', render);
audio.addEventListener('play', render);
});
});
})();
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