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Yeah this deep fake is flawed enough to be amusing. But I know we're probably only 1-2 years away from producing extremely convincing deep fakes at a whim. In

Yeah this deep fake is flawed enough to be amusing. But I know we're probably only 1-2 years away from producing extremely convincing deep fakes at a whim. In my mind, blockchain is the only thing that can counterbalance this tech. We need blockchain signed photos and videos to ensure authenticity.

jsf01 6y ago
What stops me from signing my own deepfaked video and putting that on the blockchain?
- scubbo 6y ago
  ^^ this
- sitkack 6y ago
  What stops me from writing a check to myself and cashing it?
  - blahbhthrow3748 6y ago
    a) it is absolutely conceivable to write a cheque to yourself. For example, to move cash between bank accounts b) the bank has a big database and a system of clearing cheques that ensures you cannot double-spend money by writing yourself a cheque. If you try to kite cheques by abusing the latency in the system they notice because it turns out you can just write that down in a central database too and it's pretty effective
  - wolco 6y ago
    I remember a friend doing that. More funny a friend wrote I owe you $5 and deposited and took out $10 the minimum allowed. What happened was that person lost the ability to deposit and withdraw. There is a level of trust but things will catch up to you.
  - sitkack 6y ago
    For those that aren't following along, the answer is nothing and the parents comment completely misses the point of being able to attribute something to a person.
- chrisco255 6y ago
  If you want to incriminate yourself with a deep fake, go for it. But the point is that video evidence will cease to be a reliable source of truth by the end of this decade. That's stunning, and the implications are drastic. Digital signatures to validate a source and recording method are needed.
scubbo 6y ago
I see blockchain-verification hype all over the place, and no-one's ever been able to convince me of how it would actually work in situations like this. Could you elaborate? How would you differentiate between "a 'legitimate' video that has been taken by a camera" and "a video that has been edited, and then had its provenance metadata edited to look like it is raw"? Given that there cannot possibly be any consensus protocol that verifies that "data I created myself" is legitimate, how can you prove that anything isn't legitimate?
- evanevan 6y ago
  One thing you could do is have the camera hardware sign the raw image, then make a zero knowledge proof that says original photo was signed by real hardware, and then the only edits applied to it were simple things like cropping, changing colors etc Seems reasonable to coordinate the updates with a blockchain (though not necessary for use cases where you trust the platform / coordinating entity). Disclaimer I work at a zkSNARK / blockchain company :)
  - Nursie 6y ago
    So like most solutions involving blockchains, no blockchain is actually required.
lern_too_spel 6y ago
Why blockchain? You just need the original video and its metadata to be signed by the camera. A blockchain would be just as useless here as every other place a blockchain has been applied.
- chrisco255 6y ago
  I use Ethereum every week. I buy things with Bitcoin at least once a month. I invest and bank part of my money on decentralized applications pegged to the USD in stable coins. Sorry, blockchain is more than useful and your rhetoric is out of date. The use of blockchain is important as a global timestamp that can be trusted.
  - lern_too_spel 6y ago
    The point is that everywhere you are using blockchain, other solutions are superior, which makes it useless. If I wanted to inconvenience myself, I could buy things by bartering paperclips too, but that doesn't mean that paperclips are useful as currency. The difference between paperclips and blockchain is that paperclips solve one problem better than others, while blockchain has zero real world uses where it is better than alternatives.
irjustin 6y ago
Sigh... why is blockchain the only answer? Blockchain or any signing system, PGP, shared key, is only as good as the person/entity signing it. Who will perform that signing that you trust... CNN? Fox News? Google? THE US GOVERNMENT?!
- deckarep 6y ago
  Isn’t that the whole point of blockchain? A distributed ledger with no central authority so no single entity has the power to manipulate the history...
  - irjustin 6y ago
    Let's say you can't manipulate history (it's possible btw). History is only as good as the one telling the story. In this case, who inserted the initial video? The FIRST person who inserted gets to say "this is truth". With Bitcoin what's being traded existed from the beginning. It was "mined" from the original pool. Here we all collectively said, "we trust that original pool not to be shifty". So because we trust that original source, we can trade these "items" confidently. Here the question isn't "Proof of work", it's "proof of source" which currently I cannot see a good solution for.
    - chrisco255 6y ago
      https://en.m.wikipedia.org/wiki/Proof_of_authority https://en.m.wikipedia.org/wiki/Proof_of_authority Proof of Authority. What matters is the reputation of the source. You can have varying degrees of trustworthiness based on an source's reputation, which is built up on the chain. For example, Craig Wright has faced a lot of backlash for claiming to be Satoshi Nakamoto. There's been no way for him to be proven wrong. Recently, someone signed a transaction with an address that hadn't moved Bitcoin since 2009 (implying it was an early adopter or contributor) and they called out Wright's lie (he had claimed to own that block). So Wright lost credibility. That's what we need. We need the ability to develop reputation on the blockchain and a way to punish that reputation economically for posting invalid data. EDIT (I'm out of HN replies): Reputation can be established based on a staking transaction. You create a smart contract for say, independent journalist Tim Pool. He signs it and stakes some amount and publicly declares that address to be his. He posts all his videos with a signature embedded that can be validated against that contract. The hardware itself (with algos signed by chip manufacturer) could also sign the video. An open source app could also sign. If you've got 3 signatures on a video HW, SW, and individual (associated with smart contract address) and a public blockchain timestamp, you've got a high degree of trustworthiness in that footage.
soheil 6y ago
I'm trying to figure out if this entire thread is a troll or serious

jsf01 6y ago

What stops me from signing my own deepfaked video and putting that on the blockchain?

scubbo 6y ago
^^ this
sitkack 6y ago
What stops me from writing a check to myself and cashing it?
- blahbhthrow3748 6y ago
  a) it is absolutely conceivable to write a cheque to yourself. For example, to move cash between bank accounts b) the bank has a big database and a system of clearing cheques that ensures you cannot double-spend money by writing yourself a cheque. If you try to kite cheques by abusing the latency in the system they notice because it turns out you can just write that down in a central database too and it's pretty effective
- wolco 6y ago
  I remember a friend doing that. More funny a friend wrote I owe you $5 and deposited and took out $10 the minimum allowed. What happened was that person lost the ability to deposit and withdraw. There is a level of trust but things will catch up to you.
- sitkack 6y ago
  For those that aren't following along, the answer is nothing and the parents comment completely misses the point of being able to attribute something to a person.
chrisco255 6y ago
If you want to incriminate yourself with a deep fake, go for it. But the point is that video evidence will cease to be a reliable source of truth by the end of this decade. That's stunning, and the implications are drastic. Digital signatures to validate a source and recording method are needed.

scubbo 6y ago

I see blockchain-verification hype all over the place, and no-one's ever been able to convince me of how it would actually work in situations like this. Could you elaborate? How would you differentiate between "a 'legitimate' video that has been taken by a camera" and "a video that has been edited, and then had its provenance metadata edited to look like it is raw"? Given that there cannot possibly be any consensus protocol that verifies that "data I created myself" is legitimate, how can you prove that anything isn't legitimate?

evanevan 6y ago
One thing you could do is have the camera hardware sign the raw image, then make a zero knowledge proof that says original photo was signed by real hardware, and then the only edits applied to it were simple things like cropping, changing colors etc Seems reasonable to coordinate the updates with a blockchain (though not necessary for use cases where you trust the platform / coordinating entity). Disclaimer I work at a zkSNARK / blockchain company :)
- Nursie 6y ago
  So like most solutions involving blockchains, no blockchain is actually required.

lern_too_spel 6y ago

Why blockchain? You just need the original video and its metadata to be signed by the camera. A blockchain would be just as useless here as every other place a blockchain has been applied.

chrisco255 6y ago
I use Ethereum every week. I buy things with Bitcoin at least once a month. I invest and bank part of my money on decentralized applications pegged to the USD in stable coins. Sorry, blockchain is more than useful and your rhetoric is out of date. The use of blockchain is important as a global timestamp that can be trusted.
- lern_too_spel 6y ago
  The point is that everywhere you are using blockchain, other solutions are superior, which makes it useless. If I wanted to inconvenience myself, I could buy things by bartering paperclips too, but that doesn't mean that paperclips are useful as currency. The difference between paperclips and blockchain is that paperclips solve one problem better than others, while blockchain has zero real world uses where it is better than alternatives.

irjustin 6y ago

Sigh... why is blockchain the only answer? Blockchain or any signing system, PGP, shared key, is only as good as the person/entity signing it. Who will perform that signing that you trust... CNN? Fox News? Google? THE US GOVERNMENT?!

deckarep 6y ago
Isn’t that the whole point of blockchain? A distributed ledger with no central authority so no single entity has the power to manipulate the history...
- irjustin 6y ago
  Let's say you can't manipulate history (it's possible btw). History is only as good as the one telling the story. In this case, who inserted the initial video? The FIRST person who inserted gets to say "this is truth". With Bitcoin what's being traded existed from the beginning. It was "mined" from the original pool. Here we all collectively said, "we trust that original pool not to be shifty". So because we trust that original source, we can trade these "items" confidently. Here the question isn't "Proof of work", it's "proof of source" which currently I cannot see a good solution for.
  - chrisco255 6y ago
    https://en.m.wikipedia.org/wiki/Proof_of_authority https://en.m.wikipedia.org/wiki/Proof_of_authority Proof of Authority. What matters is the reputation of the source. You can have varying degrees of trustworthiness based on an source's reputation, which is built up on the chain. For example, Craig Wright has faced a lot of backlash for claiming to be Satoshi Nakamoto. There's been no way for him to be proven wrong. Recently, someone signed a transaction with an address that hadn't moved Bitcoin since 2009 (implying it was an early adopter or contributor) and they called out Wright's lie (he had claimed to own that block). So Wright lost credibility. That's what we need. We need the ability to develop reputation on the blockchain and a way to punish that reputation economically for posting invalid data. EDIT (I'm out of HN replies): Reputation can be established based on a staking transaction. You create a smart contract for say, independent journalist Tim Pool. He signs it and stakes some amount and publicly declares that address to be his. He posts all his videos with a signature embedded that can be validated against that contract. The hardware itself (with algos signed by chip manufacturer) could also sign the video. An open source app could also sign. If you've got 3 signatures on a video HW, SW, and individual (associated with smart contract address) and a public blockchain timestamp, you've got a high degree of trustworthiness in that footage.

soheil 6y ago

I'm trying to figure out if this entire thread is a troll or serious