Metadata: The Digital Fingerprint You Had No Idea Is Attached To Every Photo You Take
Metadata: The Digital Fingerprint You Had No Idea Is Attached To Every Photo You Take
BY TYLER DURDEN SUNDAY, MAR 28, 2021 - 04:00 PM
In a day and age where everyone is walking around carrying a
portable GPS/supercomputer in their pockets, it should be of no surprise that
location data can help track you at almost any given point in the day.
But while this may be semi-expected, one way in which
people may not know they're offering up information is through photographs.
Such was the topic of a new BBC report,
which delved into exactly how much information
people are offering up with their photo metadata - the digital
"fingerprint" that's attached to every digital photo you take.
Metadata became a national issue when comparisons of two
photographs of former President Trump at Walter Reed Medical Center were
scrutinized closely to try and determine whether they were staged or not, BBC
notes. Metadata also led to authorities being able to detain John McAfee in
2012, after a photograph's location data revealed he was in Guatemala at the
time.
This data "automatically and parasitically burrows itself
into every photo you take," BBC notes. And while it's not impossible to
get rid of, most people don't even realize that it's there before widely
sharing their photographs on social media. And while some platforms remove
sensitive information, like where a photo was taken, others don't.
The tool has become useful for police investigations, who often use it to place criminals at a scene. But the data can clearly be a slippery slope and be used for nefarious purposes, as well.
And as the BBC notes, it's not just the metadata hidden in your
photos. They also contain a "unique personal identifier linking every
image you capture to the specific camera used". The report goes on to
describe how unique imaging sensors are, and how that data is stored:
To understand what this identifier is, you first have to
understand how a photo is captured. Central to every digital camera, including
those inside smartphones, is its imaging sensor. This is composed of a grid of
millions of silicon "photosites", which are cavities that absorb
photons (light). Due to a phenomenon known as the photoelectric effect, the
absorption of photons causes a photosite to eject electrons a bit like a
nightclub bouncer....
The different sensitivities of the photosites creates a type of
imperceptible image watermark. Although unintentional, it acts like a
fingerprint, unique to your camera’s sensor, which is imprinted onto every
photo you take. Much like snowflakes, no two imaging
sensors are alike.
The good news, however, is that the data can also be used to
help identify fake photographs. This can be helpful in a day and age where even
deepfake video, let
alone faked photographs, are starting to look flawless. Hany Farid, a
professor in electrical engineering and computer sciences at the University of
California, said that photo fingerprinting can "have positive and
negative uses".
Jessica Fridrich of Binghamton University in New York state, for
example, has patented a photo fingerprinting technique, which has
subsequently "been officially approved for use as forensic evidence in
court cases in the United States."
And how can one avoid sending out their personal data when just
trying to take a couple of photos of the family bar-b-que? BBC notes there's
plenty of tools - like EXIFTool - that can help you access,
and scrub, metadata.
Comments
Post a Comment