The workflow is similar to that of ObscuraCam, but with a few key differences. Notice that on start-up, the app triggers the on-board sensors. (Notifications in the top right corner clearly indicate the GPS and Bluetooth modules have been turned on.) This allows the app to register sensory and atmospheric data throughout the session. These “bundles” of data contain the following:
Whether the user is taking a picture, or editing an existing piece of media, the app registers the goings-on, and signs each bundle of data with the user’s public key. This mean that all actions taken on a piece of media (from capture to editing) are attributed to the user.
As with ObscuraCam, the user can perform image filtering and obfuscation on image regions. InformaCam also adds the “Identify” filter, which prompts the user for the subject’s name (or pseudonym) and to fill in whether or not the subject has given his or her consent to be filmed. This checklist of subject permissions can be further developed to match the needs of any organization to provide further protection to the people in front of the camera. Notice again the sensor notifications: the context surrounding each edit to the image is recorded and will be inserted into the media as metadata once the media is saved.
When the user saves the image or video, a dialog appears prompting her to choose one or more “trusted destinations.” This could be an organization, a news outlet, or any friend whose PGP key is known to you. A copy of the unredacted, data-rich image will be created and encrypted to those parties. At the same time, a redacted and data-stripped version is made available to share with anyone, anywhere.
The metadata is organized in four categories: intent, consent, geneaology, and data. Here’s a rundown of what these categories mean.
This expresses information about the media’s creator, and the rules governing how this particular media object can be shared, and to whom.
This bucket of information regards the subjects contained in the image. Each subject is identified (by a name or pseudonym selected by the user) along with their stated preferences regarding treatment of their likeness. For example, if Bobby insists that he wants his face to be fully redacted (rather than blurred) this preference should be registered in metadata.
This information regards chain-of-custody, and represents how the media was acquired, and if a particular image or video is a duplicate of another.
This category includes all standard metadata (timestamp, acquired sensory data, location and movement data) that have been collected during the lifetime of the image, from the moment it was opened to the instant it was saved.
A sample metadata bundle for an image taken with InformaCam looks like this in JSON notation:
{
"data":{
"device":{
"bluetoothInformation":{
"selfOrNeighbor":-1,
"deviceBTAddress":"00:25:36:79:EC:6C",
"deviceBTName":"nexxxie"
},
"imei":"363289131048142"
},
"sourceType":101,
"imageRegions":[
{
"regionDimensions":{
"height":256,
"width":256.00006103515625
},
"regionCoordinates":{
"left":527.705078125,
"top":196.15255737304688
},
"obfuscationType":"Identify",
"location":{
"locationType":11,
"locationData":{
"gpsCoords":"[40.7085011,-73.9668647]",
"cellId":"36789325"
}
},
"captureTimestamp":{
"timestamp":1326216508313,
"timestampType":7
},
"subject":{
"consentGiven":"general_consent",
"informedConsentGiven":true,
"subjectName":"Harlo!"
},
"unredactedRegion":"I@4070cf30"
}
],
"imageHash":"f18e7510faaad0d942db68b5c75f219a",
},
"geneaology":{
"dateAcquired":0,
"localMediaPath":"\/mnt\/sdcard\/DCIM\/Camera\/1326216520426.jpg",
"dateCreated":1326216527629
},
"intent":{
"owner":{
"ownershipType":25,
"ownerKey":"MY-IDENTITY-IS-HERE"
},
"securityLevel":1,
"intendedDestination":"[\"harlo.holmes@gmail.com\"]"
}