14 ms·

It'd be too easy to fake, just replace the sensor in an approved camera with your own data feed. And that's assuming it wouldn't be somewhat trivial to dump ke

It'd be too easy to fake, just replace the sensor in an approved camera with your own data feed. And that's assuming it wouldn't be somewhat trivial to dump keys from one or more cameras on the market to create a an easy tool or resignvideo.com... which is a massive assumption. As the movie industry has already seen, cryptography doesn't help you when you push out the keys to everyone. It'd be about as effective as DRM is at stopping video piracy.

tylerhou 7y ago
You could go on the level of Apple - hardware security chip with presigned bootloader + a chain of trust to boot the OS, and the private key stored in a secure enclave. Then generate a cert for every second of video or so and embed it into the media format. Don’t sign the video if you detect any foreign hardware.
- buildzr 7y ago
  You could try but it'd still be possible to just fake it at the sensor level, essentially so the IC would see your video as the analog signal coming in and encode it as if it were any other image. It's basically the "analog hole" of the video world. If you wanted to do the cheap version of this you could probably set up a screen with proper lighting such that it'd line up well enough that screen and sensor pixels matched closely making it near if not completely impossible to tell a screen was involved. Worse, such a signature on a fake video may give people false confidence in it being real, when really it still needs scrutiny especially if a possible state level or dedicated attacker is involved.
  - floatingatoll 7y ago
    Nikon’s been offering chip-based video crypto for years, it’s just not popular in consumer-grade hardware yet. If it was, we’d all be up in arms about our devices having a unique fingerprint in every photo (or video) that could be used to track us.
  - anbop 7y ago
    You could have onboard acceleration and depth sensors on the camera to make the fake costlier to produce.
  - alasdair_ 7y ago
    >If you wanted to do the cheap version of this you could probably set up a screen with proper lighting such that it'd line up well enough that screen and sensor pixels matched closely making it near if not completely impossible to tell a screen was involved. You could make things more difficult by using multiple cameras (and perhaps some other sensors) to detect a 3D scene rather than just a 2D representation, but I agree that it's all ultimately fakeable.
gambler 7y ago
You're not thinking this through. The problem isn't that creators can make fake videos (which would be analogous to DRM). Let them. There is no harm in it. The problem is that users have no way of verifying true videos. This can be solved with cryptography, because both parties involved (creators and viewers) would want this to work. In other words, DRM is about forcing everyone to do a thing. Verification is about allowing willing participants to check a thing. Different scenarios. Companies could make tamper-proof sensor modules that do the signing right where it matters. The important thing is to make sure they aren't astronomically priced and don't compromise privacy.
- anbop 7y ago
  Play deepfake on a TV, point signed camera at it.
  - gambler 7y ago
    Have you ever tried this? The quality will be awful. As far as I'm concerned, the need to use a real camera to capture real light is sufficient to thwart creation of truly convincing fakes.
    - jdietrich 7y ago
      >Have you ever tried this? Yes. It used to be the industry standard method for recording TV programmes prior to the invention of videotape recorders. If you know what you're doing and use the right equipment, the generational quality loss is very minor. https://en.wikipedia.org/wiki/Kinescope https://en.wikipedia.org/wiki/Kinescope
      - gambler 7y ago
        >It used to be the industry standard method for recording TV programmes prior to the invention of videotape recorders. Back when everything was analog and low-resolution, had noise and artifacts anyway, sure. Do you have a video that compares modern digital 1080p with its best "Kinescoped" version? You have to deal with parallax, mismatched frame frequencies, pixels and differences between natural light and whatever spectrum the source monitor produces. I have never seen a recording of a screen that looked anywhere close in quality to the original in 1080p.
swiley 7y ago
Better would be for people/organizations to be in the habit of signing things they publish. This is fundamentally just another MITM attack.
nessunodoro 7y ago
Invisible watermarking can be encoded into video frames. https://inis.iaea.org/collection/NCLCollectionStore/_Public/45/099/45099925.pdf?r=1&r=1 https://inis.iaea.org/collection/NCLCollectionStore/_Public/... I remember visiting the MIT media lab when I was in college, they described the audio version of "invisible watermarking" - manipulating the source audio with a generated acoustic effect, similar to a doppler shift. The effect is not detected by the human ear, but signal analysis can translate it into binary metadata, such as a DRM signature.
- buildzr 7y ago
  What's the relevant application here? If you're suggesting this could be added by video editing software or display hardware, it seems if everyone knew about such watermarking it'd be trivial to strip out and turn into noise, so it would work publicly exactly once. If you're saying it'd be added by legitimate camera sensors, well it wouldn't beat the possibilities I suggested already of simply feeding tampered data to the sensor.
  - nessunodoro 7y ago
    As it was described to me, the watermarking is encoded in such a way that it would be prohibitively expensive computationally to offset or overwrite it.
    - buildzr 7y ago
      Okay, let's assume that's remotely possible. Injecting such a watermark at the camera doesn't help you - in fact, such a watermark you're describing is attempting to be resistant to things like re-transcoding so it might actually be carried through an editing process successfully. Not to mention the previous camera sensor bypasses. So let's ignore camera based options. You have to get all video editing software or displays to inject such a watermark while keeping their keys private. Getting direct LVDS access to a panel and being able to write your own firmware pretty much bypasses most display options, and well... software based options are even worse I'd say, software is open to such a wide array of attacks and the mere existence of open source video editing tools, including FaceSwap itself makes this seem... questionable at best.
bob_doggo 7y ago
As a random user, this is what I would like: When I watch a video-clip of, let's say a press-conference, it would be nice to have a way to verify that the video-clip is indeed the one recorded by whatever journalist was at the press-conference. It's not about camera hardware, it's about making it easy to check if the video someone is presenting to me is what they claim it is.

tylerhou 7y ago

You could go on the level of Apple - hardware security chip with presigned bootloader + a chain of trust to boot the OS, and the private key stored in a secure enclave. Then generate a cert for every second of video or so and embed it into the media format. Don’t sign the video if you detect any foreign hardware.

buildzr 7y ago
You could try but it'd still be possible to just fake it at the sensor level, essentially so the IC would see your video as the analog signal coming in and encode it as if it were any other image. It's basically the "analog hole" of the video world. If you wanted to do the cheap version of this you could probably set up a screen with proper lighting such that it'd line up well enough that screen and sensor pixels matched closely making it near if not completely impossible to tell a screen was involved. Worse, such a signature on a fake video may give people false confidence in it being real, when really it still needs scrutiny especially if a possible state level or dedicated attacker is involved.
- floatingatoll 7y ago
  Nikon’s been offering chip-based video crypto for years, it’s just not popular in consumer-grade hardware yet. If it was, we’d all be up in arms about our devices having a unique fingerprint in every photo (or video) that could be used to track us.
- anbop 7y ago
  You could have onboard acceleration and depth sensors on the camera to make the fake costlier to produce.
- alasdair_ 7y ago
  >If you wanted to do the cheap version of this you could probably set up a screen with proper lighting such that it'd line up well enough that screen and sensor pixels matched closely making it near if not completely impossible to tell a screen was involved. You could make things more difficult by using multiple cameras (and perhaps some other sensors) to detect a 3D scene rather than just a 2D representation, but I agree that it's all ultimately fakeable.

gambler 7y ago

You're not thinking this through. The problem isn't that creators can make fake videos (which would be analogous to DRM). Let them. There is no harm in it. The problem is that users have no way of verifying true videos. This can be solved with cryptography, because both parties involved (creators and viewers) would want this to work. In other words, DRM is about forcing everyone to do a thing. Verification is about allowing willing participants to check a thing. Different scenarios. Companies could make tamper-proof sensor modules that do the signing right where it matters. The important thing is to make sure they aren't astronomically priced and don't compromise privacy.

anbop 7y ago
Play deepfake on a TV, point signed camera at it.
- gambler 7y ago
  Have you ever tried this? The quality will be awful. As far as I'm concerned, the need to use a real camera to capture real light is sufficient to thwart creation of truly convincing fakes.
  - jdietrich 7y ago
    >Have you ever tried this? Yes. It used to be the industry standard method for recording TV programmes prior to the invention of videotape recorders. If you know what you're doing and use the right equipment, the generational quality loss is very minor. https://en.wikipedia.org/wiki/Kinescope https://en.wikipedia.org/wiki/Kinescope
    - gambler 7y ago
      >It used to be the industry standard method for recording TV programmes prior to the invention of videotape recorders. Back when everything was analog and low-resolution, had noise and artifacts anyway, sure. Do you have a video that compares modern digital 1080p with its best "Kinescoped" version? You have to deal with parallax, mismatched frame frequencies, pixels and differences between natural light and whatever spectrum the source monitor produces. I have never seen a recording of a screen that looked anywhere close in quality to the original in 1080p.

swiley 7y ago

Better would be for people/organizations to be in the habit of signing things they publish. This is fundamentally just another MITM attack.

nessunodoro 7y ago

Invisible watermarking can be encoded into video frames. https://inis.iaea.org/collection/NCLCollectionStore/_Public/45/099/45099925.pdf?r=1&r=1 https://inis.iaea.org/collection/NCLCollectionStore/_Public/... I remember visiting the MIT media lab when I was in college, they described the audio version of "invisible watermarking" - manipulating the source audio with a generated acoustic effect, similar to a doppler shift. The effect is not detected by the human ear, but signal analysis can translate it into binary metadata, such as a DRM signature.

buildzr 7y ago
What's the relevant application here? If you're suggesting this could be added by video editing software or display hardware, it seems if everyone knew about such watermarking it'd be trivial to strip out and turn into noise, so it would work publicly exactly once. If you're saying it'd be added by legitimate camera sensors, well it wouldn't beat the possibilities I suggested already of simply feeding tampered data to the sensor.
- nessunodoro 7y ago
  As it was described to me, the watermarking is encoded in such a way that it would be prohibitively expensive computationally to offset or overwrite it.
  - buildzr 7y ago
    Okay, let's assume that's remotely possible. Injecting such a watermark at the camera doesn't help you - in fact, such a watermark you're describing is attempting to be resistant to things like re-transcoding so it might actually be carried through an editing process successfully. Not to mention the previous camera sensor bypasses. So let's ignore camera based options. You have to get all video editing software or displays to inject such a watermark while keeping their keys private. Getting direct LVDS access to a panel and being able to write your own firmware pretty much bypasses most display options, and well... software based options are even worse I'd say, software is open to such a wide array of attacks and the mere existence of open source video editing tools, including FaceSwap itself makes this seem... questionable at best.

bob_doggo 7y ago

As a random user, this is what I would like: When I watch a video-clip of, let's say a press-conference, it would be nice to have a way to verify that the video-clip is indeed the one recorded by whatever journalist was at the press-conference. It's not about camera hardware, it's about making it easy to check if the video someone is presenting to me is what they claim it is.