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What this is starting to reveal is that there's a clear need for some kind of chain of custody system that guarantees the authenticity of what we see. Nikon/Can

What this is starting to reveal is that there's a clear need for some kind of chain of custody system that guarantees the authenticity of what we see. Nikon/Canon tried doing this in the past, but improper storage of private keys lead to vulnerabilities. As far as I'm aware it's never extended to video either. With modern secure hardware keys it may yet be possible. The difficulty is that any kind of photo/video manipulation would break the signature (and there are practical reasons to want to be able to edit videos obviously). In the ideal world, any mutation to the original source content could be traceable to the original source content. But that's not an easy problem to solve.

throw__away7391 3y ago
No, we are merely returning to the pre-photography state of things where a mere printed image is not sufficient evidence for anything.
- tass 3y ago
  There goes the dashcam industry…
  - barbazoo 3y ago
    You're being downvoted but I think the comment raises a good question. what will happen when someone gets accused of doctoring their dashcam footage? Or any footage used for evidence.
    - tass 3y ago
      I wasn’t really kidding with my comment. I just recently used camera footage as part of an accident claim and the assessor immediately said “that wasn’t your fault, we take responsibility on behalf of the driver”. In a few years time when (if) faking realistic footage becomes trivial, I suspect this kind of video will have a much, much higher level of scrutiny or only be accepted from certain sources such as government owned traffic cameras.
- hx8 3y ago
  True, an image, audio clip, or video is not enough evidence to establish truth. We still need a way to establish truth. It's important for security cameras, for politics, and for public figures. Here are some things we could start looking into. * Cameras that sign their output. Yes, this camera caught this video, and it hasn't been modified. This is a must for recordings being used in court evidence IMO. Otherwise framing a crime is as easy as a few deep fakes and planting some DNA or fingerprints at the scene of the crime. * People digitally signing pictures/audio/videos of them. Even if they digitally modified the data it shows that they consent to having their image associated with that message. It reduces the strength of the attack vector of deep fake videos for reputation sabotage. * Malicious content source detection and flagging. Think email spam filter type tagging of fake content. Community notes on X would be another good example. * Digital manipulation detection. I'm less than hopeful this will be the way in the long term, but could be used to disprove some fraud.
  - alchemist1e9 3y ago
    Blockchains can be used for cryptography time-stamping. I’ve always had a suspicion that governments and large companies would prefer a world without hard cryptographic proofs. After wikileaks they noticed DKIM can cause them major blowback. Somehow general public isn’t aware all the emails were proven authentic with DKIM signatures and even in fairly educated circles people believe the “emails were fake” but it’s not actually possible.
    - PeterisP 3y ago
      Quite the opposite, governments and large companies even explicitly run services for digital timestamping of documents - if I wanted to potentially assert some facts in court, I'd definitely prefer having that e-document with a timestamp notarized from my local government service instead of Bitcoin, because while the cryptography is the same, it would be much simpler from the practical legal perspective, requiring less time and effort and cost to get the court to accept that.
  - alex_suzuki 3y ago
    Signing is great, but the hard part is managing keys and trust.
- BobaFloutist 3y ago
  Pre-photography it at least took effort, practice, and time, to draw something convincing. Any skill with that much of a barrier to entry kind of automatically reduces the ability to be anonymous. And we didn't have the ability to instantaneously distribute images world-wide.
- anigbrowl 3y ago
  merely You say this as if it were not a big deal, but losing a century's worth of authentication infrastructure/practises is a Bad Thing which will have large negative externalities.
  - throw__away7391 3y ago
    It isn't really though. It has been technical possible to convincingly doctor photos for some time already, gradually getting easier, cheaper, and faster with time for decades, and even now the currently available tech has limitations and the full change is not going to happen overnight.
deleted 3y ago
[deleted]
bonton89 3y ago
I expect this type of system to be implemented in my lifetime. It will allow whistleblowers and investigative sources to be discredited or tracked down and persecuted.
- 20after4 3y ago
  Unfortunately that seems inevitable.
PeterisP 3y ago
I think it's practically impossible for such a system to be globally trustworthy due to the practical inevitability of "but improper storage of private keys lead to vulnerabilities" scenarios. People will expect or require that chain of custody only if all or at least the vast majority of the content they want would have that chain of custody. Photo/video content will have that chain of custody only if all or almost all of devices recording that content will support it - including all the cheapest mass-produced devices in reasonably widespread use anywhere in the world. And that chain of custody provides the benefit only if literally 100% of these manufacturers have their private keys secure 100% of the time, which is simply not happening; at least one such key will leak, if not unintentionally then intentionally for some intelligence agency who wants to fake content. And what do you do once you see a leak of the private keys used for signing the certificates for the private keys securely embedded in (for example) all of 2029 Huawei smartphones, which could be like 200 million phones? The users won't replace their phones just because of that, and you'll have all these users making content - so everyone will have to choose to either auto-block and discard everything from all those 200 million users, or permit content with a potentially fake chain of custody; and I'm totally certain that most people will prefer the latter.
- macrolime 3y ago
  Multisig by the user and camera manufacturer can help to some extent.
  - PeterisP 3y ago
    Multisig requires user cooperation, many users will not care to cooperate, and chain of custody verification really starts working only if you can get (force) ~100% of legitimate users globally to adopt the system. Also, for the potential creators of political fakes, such a multisig won't change things - getting a manufacturer's key may take some effort, but getting (and 'burning') keys of a dozen random people is relatively trivial in many ways - e.g. buying off of poor people, stealing from compromised random machines, or simply issuing fake identities for state-backed actors.
qingcharles 3y ago
None of that works, it's simply theatre. I can just take a (crypto-signed) photo of another photo.
- pedalpete 3y ago
  The public block chain would show the chain of custody/ownership, so the photo of a photo would show the the final crypto signature does not belong to the claimed owner. You are correct that I as a viewer can't just rely on a crypto-signature like a watermark, I'd have to verify the chain of custody, but if I wanted to do that, it is available to do so.

throw__away7391 3y ago

No, we are merely returning to the pre-photography state of things where a mere printed image is not sufficient evidence for anything.

tass 3y ago
There goes the dashcam industry…
- barbazoo 3y ago
  You're being downvoted but I think the comment raises a good question. what will happen when someone gets accused of doctoring their dashcam footage? Or any footage used for evidence.
  - tass 3y ago
    I wasn’t really kidding with my comment. I just recently used camera footage as part of an accident claim and the assessor immediately said “that wasn’t your fault, we take responsibility on behalf of the driver”. In a few years time when (if) faking realistic footage becomes trivial, I suspect this kind of video will have a much, much higher level of scrutiny or only be accepted from certain sources such as government owned traffic cameras.
hx8 3y ago
True, an image, audio clip, or video is not enough evidence to establish truth. We still need a way to establish truth. It's important for security cameras, for politics, and for public figures. Here are some things we could start looking into. * Cameras that sign their output. Yes, this camera caught this video, and it hasn't been modified. This is a must for recordings being used in court evidence IMO. Otherwise framing a crime is as easy as a few deep fakes and planting some DNA or fingerprints at the scene of the crime. * People digitally signing pictures/audio/videos of them. Even if they digitally modified the data it shows that they consent to having their image associated with that message. It reduces the strength of the attack vector of deep fake videos for reputation sabotage. * Malicious content source detection and flagging. Think email spam filter type tagging of fake content. Community notes on X would be another good example. * Digital manipulation detection. I'm less than hopeful this will be the way in the long term, but could be used to disprove some fraud.
- alchemist1e9 3y ago
  Blockchains can be used for cryptography time-stamping. I’ve always had a suspicion that governments and large companies would prefer a world without hard cryptographic proofs. After wikileaks they noticed DKIM can cause them major blowback. Somehow general public isn’t aware all the emails were proven authentic with DKIM signatures and even in fairly educated circles people believe the “emails were fake” but it’s not actually possible.
  - PeterisP 3y ago
    Quite the opposite, governments and large companies even explicitly run services for digital timestamping of documents - if I wanted to potentially assert some facts in court, I'd definitely prefer having that e-document with a timestamp notarized from my local government service instead of Bitcoin, because while the cryptography is the same, it would be much simpler from the practical legal perspective, requiring less time and effort and cost to get the court to accept that.
- alex_suzuki 3y ago
  Signing is great, but the hard part is managing keys and trust.
BobaFloutist 3y ago
Pre-photography it at least took effort, practice, and time, to draw something convincing. Any skill with that much of a barrier to entry kind of automatically reduces the ability to be anonymous. And we didn't have the ability to instantaneously distribute images world-wide.
anigbrowl 3y ago
merely You say this as if it were not a big deal, but losing a century's worth of authentication infrastructure/practises is a Bad Thing which will have large negative externalities.
- throw__away7391 3y ago
  It isn't really though. It has been technical possible to convincingly doctor photos for some time already, gradually getting easier, cheaper, and faster with time for decades, and even now the currently available tech has limitations and the full change is not going to happen overnight.

deleted 3y ago

[deleted]

bonton89 3y ago

I expect this type of system to be implemented in my lifetime. It will allow whistleblowers and investigative sources to be discredited or tracked down and persecuted.

20after4 3y ago
Unfortunately that seems inevitable.

PeterisP 3y ago

I think it's practically impossible for such a system to be globally trustworthy due to the practical inevitability of "but improper storage of private keys lead to vulnerabilities" scenarios. People will expect or require that chain of custody only if all or at least the vast majority of the content they want would have that chain of custody. Photo/video content will have that chain of custody only if all or almost all of devices recording that content will support it - including all the cheapest mass-produced devices in reasonably widespread use anywhere in the world. And that chain of custody provides the benefit only if literally 100% of these manufacturers have their private keys secure 100% of the time, which is simply not happening; at least one such key will leak, if not unintentionally then intentionally for some intelligence agency who wants to fake content. And what do you do once you see a leak of the private keys used for signing the certificates for the private keys securely embedded in (for example) all of 2029 Huawei smartphones, which could be like 200 million phones? The users won't replace their phones just because of that, and you'll have all these users making content - so everyone will have to choose to either auto-block and discard everything from all those 200 million users, or permit content with a potentially fake chain of custody; and I'm totally certain that most people will prefer the latter.

macrolime 3y ago
Multisig by the user and camera manufacturer can help to some extent.
- PeterisP 3y ago
  Multisig requires user cooperation, many users will not care to cooperate, and chain of custody verification really starts working only if you can get (force) ~100% of legitimate users globally to adopt the system. Also, for the potential creators of political fakes, such a multisig won't change things - getting a manufacturer's key may take some effort, but getting (and 'burning') keys of a dozen random people is relatively trivial in many ways - e.g. buying off of poor people, stealing from compromised random machines, or simply issuing fake identities for state-backed actors.

qingcharles 3y ago

None of that works, it's simply theatre. I can just take a (crypto-signed) photo of another photo.

pedalpete 3y ago
The public block chain would show the chain of custody/ownership, so the photo of a photo would show the the final crypto signature does not belong to the claimed owner. You are correct that I as a viewer can't just rely on a crypto-signature like a watermark, I'd have to verify the chain of custody, but if I wanted to do that, it is available to do so.