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A comment on NFT projects are just MLMs for tech elites. Parent comment

Re:NFT projects are just MLMs for tech elites by mcintyre1994 on Friday October 01, 2021 @07:39AM (#28717155)
Can you give an example of the proprietary entity you're referring to? I was curious so I took a short course that covered minting NFTs with Solidity, and the way it seemed to work is that the JSON strings (which contain the base64 encoded image) are stored (as an ERC-721 token) on the Ethereum blockchain. Eg. you can see a random such token here: https://rinkeby.etherscan.io/token/0x6b96751051cd25c29cdcea7...

The only proprietary entity involved in that process seems to be Alchemy. My understanding of them is a bit vague but they seem to just help with making miners aware of the new contract and getting it distributed. But that's just the contract, once it's deployed it's nothing to do with them and the NFTs AFAIK don't pass through them at all.

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Re:NFT projects are just MLMs for tech elites by dkersten on Friday October 01, 2021 @11:38AM (#28719841)
Maybe a stupid question, but where do I find the base64 encoded image in your linked token? The only thing I can see is a transaction moving it from one address to another, the contract bytecode (which I guess might encode an image but its definitely not obvious[1]) and the "extra data" hex in the transaction (that doesn't appear to be an encoded image either, from what I can tell).

I'm probably missing something, so if you could let me know where to look, that'd be nice!

[1] I decompiled it here: https://rinkeby.etherscan.io/bytecode-decompiler?a=0x6b96751...

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Re:NFT projects are just MLMs for tech elites by mcintyre1994 on Friday October 01, 2021 @12:09PM (#28720255)
I'm not sure about that either TBH! If you copy the to address (0x22f542cd394fba213df8d1f6c46f454b74e05503) and paste it into testnets.opensea.io then you can see the collection here: https://testnets.opensea.io/0x22f542cd394fba213df8d1f6c46f45...

The contract has no mention of opensea, so they must be reading it from the blockchain somehow - but I guess etherscan doesn't display these tokens in a similar way for some reason. It's all pretty new to me and I definitely don't have a super joined up understanding of it all!

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Re:NFT projects are just MLMs for tech elites by miracle2k on Friday October 01, 2021 @10:43PM (#28725473)
To query the URI of your tokens through your contract, you need to interact with its ABI through code; alternatively, you can upload the ABI to Etherscan, which will provide a UI to query it.

You can use the URI to store base64 encoded image or svg data, and that is super cool; but will be too expensive for larger images, at which point you will link to an IPFS-hosted url.

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Re:NFT projects are just MLMs for tech elites by mcintyre1994 on Saturday October 02, 2021 @10:58AM (#28729061)
Ah thankyou! In that course we did write a web frontend that interacts with the contract ABI to mint the NFTs, but we didn’t do the display side. I’m curious how opensea are doing it, because they can display NFTs from my contract without me ever giving them the ABI. Can you go from decompiled contract (like etherscan can generate) -> ABI maybe?
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Re:NFT projects are just MLMs for tech elites by miracle2k on Saturday October 02, 2021 @03:50PM (#28731464)
When you are implementing an NFT, you are likely implementing either the ERC 721 or the ERC 1155 interfaces; as such, certain standard functions will be available using a standard ABI call.

So OpenSea will just try to call `tokenURI`; if you have implemented the interface correctly, that will succeed, if not, OpenSea will not show a placeholder image.

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