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If the same key could be integrated into video stream, we could have a way to avoid deep fakes? Is the video manipulated? Calculate the hash/key, and use a pub

If the same key could be integrated into video stream, we could have a way to avoid deep fakes? Is the video manipulated? Calculate the hash/key, and use a public key lookup for RPi to verify. To avoid hacking of the key, embed every camera with a unique private key.

gspr 5y ago
With a central authority to issue unique "authentic camera keys"? What dystopian nonsense you're suggesting! Because without such an authority, what's to stop the deepfake source from generating its own unique key? And we're back to square one.
- deleted 5y ago
  [deleted]
- dmurray 5y ago
  You don't need a centralized authority. Every manufacturer can issue their own keys. I take a digitally signed photo and tell you "I took the photo with this tamper proof Canon camera, and I can prove it by taking more photos of any subject you ask for and signing them with the same key". If you worry that I made an authentic-looking counterfeit Canon camera (but you're satisfied I couldn't have extracted the private key from a real one), Canon can confirm that they sold a camera with that key.
  - gspr 5y ago
    But what prevents me from saying I'm a manufacturer of tamper proof gspr cameras, that just happen to generate deepfakes? Surely there will be enough cheap devices out there that not everyone can be expected to remember the names of venerable manufacturers? I personally have no idea who makes the camera in my phone. Anyway, the point is moot. The analog hole is still there, you'll just feed the pixels straight from the deep fake generator into the Really Real Tamper Proof Canon's CCD.
digitallyfree 5y ago
One method would be to have a unique key burned into the image sensor by the manufacturer. That key will be in turn used to cryptographically sign the raw signal output from the sensor to verify that the image was indeed generated by that specific sensor. Now if the image is compressed, this is obviously moot. But for important documentation and the like, it's feasible to store the signed raw signal to confirm that the image was taken by that specific camera. Of course, this depends on the security of the keystore, the trustworthiness of the manufacturer, etc.
- yjftsjthsd-h 5y ago
  > One method would be to have a unique key burned into the image sensor by the manufacturer. That key will be in turn used to cryptographically sign the raw signal output from the sensor to verify that the image was indeed generated by that specific sensor. This would be horrible for privacy, although somewhat mitigated if the camera program/app discarded the signature by default.
  - digitallyfree 5y ago
    Yeah it would, and ideally it should be possible for the user to choose to include the signature or not in their images. Though I wouldn't be surprised to see this type of tech being the norm in the future, perhaps in a sneaky way like what they did with printers and digital watermarking (https://en.wikipedia.org/wiki/Machine_Identification_Code https://en.wikipedia.org/wiki/Machine_Identification_Code). We may even see this in other integrated sensors like a MEMS mic with a built-in AD on the silicon.
- sudosysgen 5y ago
  This isn't doable. Nothing prevents you from gluing or projecting a screen directly into the sensor, after tone mapping the image properly. There is no winning. It wouldn't even be expensive!
  - BlueTemplar 5y ago
    Yes, that has been repeatedly pointed out. And yet the industry still did it and your digital cables carrying video aren't going to work properly without the HDCP DRM.
irjustin 5y ago
possible to hardware hack to create a deep fake and simply pass it though the camera CCD to get it be crypto signed.
- mikepurvis 5y ago
  Or just take-a-picture-of-a-picture. It's possible to do such things much more convincingly than when Trump tweeted out that classified satellite pic in 2019 with a flash visible in the middle of it.
  - kevin_thibedeau 5y ago
    Satellite imagery suffers from sunlight glint that oversaturates the CCD. That isn't a mark of a fake.
    - mikepurvis 5y ago
      Sure, okay. I was just following what I had thought to be the widely accepted narrative on this, eg: "CNBC reported that Trump was shown the photo during the briefing. A flash visible in the center of the image suggests Trump or someone else took a photo of the original image — which Hanham says might have been the intelligence briefing slide." https://www.npr.org/2019/09/05/758038714/can-president-trump-really-tweet-a-highly-classified-satellite-photo-yep-he-can https://www.npr.org/2019/09/05/758038714/can-president-trump... In any case, the point is that with proper staging, you could absolutely take a picture-of-a-picture in a way that would result in the image being marked as genuine and untampered, even accounting for the signing info including a GPS-based time- and position-stamp and including camera details like focal length.
deleted 5y ago
[deleted]
yjftsjthsd-h 5y ago
What stops someone from pointing this camera at a really high resolution display showing anything they want? The analog hole goes both ways.
- sudosysgen 5y ago
  You could even just remove the lens and glue a screen to the sensor.

gspr 5y ago

With a central authority to issue unique "authentic camera keys"? What dystopian nonsense you're suggesting! Because without such an authority, what's to stop the deepfake source from generating its own unique key? And we're back to square one.

deleted 5y ago
[deleted]
dmurray 5y ago
You don't need a centralized authority. Every manufacturer can issue their own keys. I take a digitally signed photo and tell you "I took the photo with this tamper proof Canon camera, and I can prove it by taking more photos of any subject you ask for and signing them with the same key". If you worry that I made an authentic-looking counterfeit Canon camera (but you're satisfied I couldn't have extracted the private key from a real one), Canon can confirm that they sold a camera with that key.
- gspr 5y ago
  But what prevents me from saying I'm a manufacturer of tamper proof gspr cameras, that just happen to generate deepfakes? Surely there will be enough cheap devices out there that not everyone can be expected to remember the names of venerable manufacturers? I personally have no idea who makes the camera in my phone. Anyway, the point is moot. The analog hole is still there, you'll just feed the pixels straight from the deep fake generator into the Really Real Tamper Proof Canon's CCD.

digitallyfree 5y ago

One method would be to have a unique key burned into the image sensor by the manufacturer. That key will be in turn used to cryptographically sign the raw signal output from the sensor to verify that the image was indeed generated by that specific sensor. Now if the image is compressed, this is obviously moot. But for important documentation and the like, it's feasible to store the signed raw signal to confirm that the image was taken by that specific camera. Of course, this depends on the security of the keystore, the trustworthiness of the manufacturer, etc.

yjftsjthsd-h 5y ago
> One method would be to have a unique key burned into the image sensor by the manufacturer. That key will be in turn used to cryptographically sign the raw signal output from the sensor to verify that the image was indeed generated by that specific sensor. This would be horrible for privacy, although somewhat mitigated if the camera program/app discarded the signature by default.
- digitallyfree 5y ago
  Yeah it would, and ideally it should be possible for the user to choose to include the signature or not in their images. Though I wouldn't be surprised to see this type of tech being the norm in the future, perhaps in a sneaky way like what they did with printers and digital watermarking (https://en.wikipedia.org/wiki/Machine_Identification_Code https://en.wikipedia.org/wiki/Machine_Identification_Code). We may even see this in other integrated sensors like a MEMS mic with a built-in AD on the silicon.
sudosysgen 5y ago
This isn't doable. Nothing prevents you from gluing or projecting a screen directly into the sensor, after tone mapping the image properly. There is no winning. It wouldn't even be expensive!
- BlueTemplar 5y ago
  Yes, that has been repeatedly pointed out. And yet the industry still did it and your digital cables carrying video aren't going to work properly without the HDCP DRM.

irjustin 5y ago

possible to hardware hack to create a deep fake and simply pass it though the camera CCD to get it be crypto signed.

mikepurvis 5y ago
Or just take-a-picture-of-a-picture. It's possible to do such things much more convincingly than when Trump tweeted out that classified satellite pic in 2019 with a flash visible in the middle of it.
- kevin_thibedeau 5y ago
  Satellite imagery suffers from sunlight glint that oversaturates the CCD. That isn't a mark of a fake.
  - mikepurvis 5y ago
    Sure, okay. I was just following what I had thought to be the widely accepted narrative on this, eg: "CNBC reported that Trump was shown the photo during the briefing. A flash visible in the center of the image suggests Trump or someone else took a photo of the original image — which Hanham says might have been the intelligence briefing slide." https://www.npr.org/2019/09/05/758038714/can-president-trump-really-tweet-a-highly-classified-satellite-photo-yep-he-can https://www.npr.org/2019/09/05/758038714/can-president-trump... In any case, the point is that with proper staging, you could absolutely take a picture-of-a-picture in a way that would result in the image being marked as genuine and untampered, even accounting for the signing info including a GPS-based time- and position-stamp and including camera details like focal length.

deleted 5y ago

[deleted]

yjftsjthsd-h 5y ago

What stops someone from pointing this camera at a really high resolution display showing anything they want? The analog hole goes both ways.

sudosysgen 5y ago
You could even just remove the lens and glue a screen to the sensor.