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10

I'm working on a Bitcoin project, and what I've seen are: Just the Bitcoin address A url parameter-like scheme with the format "bitcoin:{plus the bitcoin address}" (no brackets used) A more elaborate url parameter that includes the amount, like "bitcoin:{bitcoin addr}?amount={the amount} Coinbase uses the last scheme and it is fully recognized by the ...


9

You can't include the USD amount, but you certainly can include the btc amount in the QR code. The QR code essentially embeds a text like this: bitcoin:1ArmoryXcfq7TnCSuZa9fQjRYwJ4bkRKfv?amount=0.005 Note the amount here is the amount in BTC. You can generate a QR code for that text using gobitcoin.io. If you just want to insert an image, you can use ...


8

The easiest way to do this is to have the QR code be a URL. For example, http://www.example.com/bitcoingiveaway/E34IKJ. Just assign a unique code to each location, the E34IKJ in my example. What that web page does is up to you. It has to track how many times it has been accessed, of course. The first time, it can send a form that allows a person to fill in ...


7

In terms of marketing, here is a very nice QR code that could be used for spreading the word about Bitcoin. It contains a link to bitcoin.org. See this thread on bitcointalk.org for more information. It was created by phelix at bitcoinx.com.


5

When using bitcoin to pay at the point-of-sale or for a face-to-face transaction, there is the problem of how to communicate the Bitcoin address to be paid in a way that the person paying can use. A bitcoin address is just data, but it is between 27 and 34 characters so that is way to much info to expect the person paying to have to manually type in. A ...


5

In ECDSA public keys are usually generated from a random private key. The simple answer then would be, that instead of using a random private key, you use the given private key and it should generate the public key. After that, perform the steps listed in the Wiki to find out the conventional notation for the public key you can use anywhere.


4

As of November 2013, Bitcoin-qt generates a QR code. Click the Addresses button at the top of the window, highlight the wallet address you want, and then click the "Show QR Code" button at the bottom of the window. Add a message, if you want, or not, and then click the "Save As" button. It will be saved as a PNG image file.


4

The QR code is simply a convenient way of sharing an address, to avoid having to type it. It encodes exactly the same information as the alphanumeric address and provides no additional security. If you have another way of giving someone an address (e.g. sending it to them by email), there is no need to use a QR code at all. How the other person verifies ...


3

I'm the founder of CryptoCoinJS and use the library for my own software. This is probably obvious, when scanning QR codes, check for both. When generating QR codes, for backup I'd just do the address and for payment requests, I'd use the URI scheme.


3

You can use QR codes with Shamir's Secret Sharing for making secure backups of deterministic wallets: http://code.google.com/p/bccapi/wiki/ManagingLongPassphrases


3

You can use also use the standard bitcoin URI QR codes to transfer bitcoin addresses from one application to another. For instance you can show your Instawallet.com bitcoin address as a QR code and drag it into the MultiBit send bitcoin screen. (www.multibit.org). It automatically parses it and creates an 'address book' entry with the bitcoin address and ...


3

Nowadays pretty much every device has a camera built in so it is much easier to scan the QR code rather than typing very long Bitcoin account address. If you have wallet in your mobile phone and you want to send money to someone he can email you the QR code and you will be able to scan it quickly with your phone and send the money. Without that you would ...


3

You generally don't publish your public keys, you give clients an address (which is usually computed from a public key, but not exactly the same). You can definitely put an address in a QRCode. Putting a logo in the QRCode doesn't change anything about that. Generally you'd put a "bitcoin:" URI in the QRCode. More information can be found in BIP21. Note ...


3

This is definitely a scam. Even if an activation fee was a legitimate thing, they would just charge that amount out of the amount you were going to receive - if you were to receive $1000 and the fee was $5, they'd just give you $995. Beyond that, no bank I'm aware of charges fees in cryptocurrencies. Don't send any money to these people.


3

A QR code encoding… a payment request specific to some payment provider is subject to the specific payment provider's terms of use. A typical range could be between a few hours and a day. an on-chain Bitcoin address remains valid indefinitely. Although address reuse is not recommended, it could be used for multiple payments. a Lightning Invoice will be ...


2

You can use any QR generator to create the image. Just select type "text", ECC level "H", and UTF-8 encoding. The QR codes are nothing more than the address. I use http://goqr.me/ for a quick online generator. Otherwise Mikael's link works well from what I've heard.


2

Do you want to just generate the QR code for one time use, or include the code generation into a program? If the latter you can use this for javascript: http://larsjung.de/qrcode/


2

Janina Lowisz of Bitnation's BlockchainID project became the first "World Citizen on the Blockchain" by making a sort of blockchain passport: Something similar could be done for identifying pets. For instructions on how she did it, see: https://github.com/MrChrisJ/World-Citizenship


2

However it is possible to generate a bitcoin QR code with a given value in USD, but it is no use since high transaction fees and highly volatile nature of bitcoin. Still, you can use third party services like CoinGate which provides you a real time convertion of USD to almost all major crypto currencies. But CoinGate will show their own BTC address to ...


2

that's not a bad idea in regards of doing business and distributing it to people. however, as far as I know, a single address is fine because the address itself is secured. the security flaw of a single address distributed will be - people can check the addresses on how good your business is doing. hehe. correct me if I'm wrong. Wishing you all the luck with ...


2

Unfortunately, that’s the hacker’s BTC address. There are way too many fake BTC QR generators nowadays, so the best way to do that is to ask your wallet to generate the QR for you (or use a well-known website).


1

Check out https://github.com/shesek/bitcoinuri. Make sure to read the warnings.


1

Here is an example of taking a 256-bit hex-encoded private key and creating an uncompressed Wallet Input Format (WIF) private key for testnet using the libbitcoin v3.0 bitcoin-explorer (bx) command line interface. bx sub-commands manual pages are located on the right column of its Wiki % echo "0000111122223333444455556666777788889999aaaabbbbccccddddeeeeffff"...


1

Yes, if you don't want the hassle of registering or giving your details to a website an ATM would be the better choice. Note that ATMs usually charge more than an online exchange. They give you a bitcoin address and its QR code as well as a private key and its QR code. The private key is all you need to have control and access of your coins on that ...


1

A QR Code is just a short-cut for a string of text. As you probably know, a Bitcoin address is also a string of text. So too, are the keys to your Bitcoin wallet. So many different things can be stored in a QR code. Is it a wallet address? Or is it a back up of a wallet with its keys? Or is it a web address? Or an email address? It can be anything. So ...


1

These wallets do: Bitcoin Wallet Mycelium


1

You don't need internet or an app. Actually, the machine can either scan a paper QR code or a mobile phone. The problem would either be that the QR code encodes different information than what you thought it does, or that the scanner of the ATM does not recognize the QR code on the screen. What you need to show is a Bitcoin address. Try to set your screen ...


1

I've met the Coinpunk developer last month at a meeting and he was discussing about how hard it was for him to create an entirely HTML5-based bitcoin QR code generator, that would work also on iOS devices. Apparently he was successful. I'd therefore suggest to look into his project which is open-source: https://github.com/kyledrake/coinpunk


1

That's a paper wallet. Search for that. bitaddress.org or paperwallet.com are examples. The way you intend to use it basically comes down to printing the private key part of a bitcoin wallet and giving that to someone else. Another use would be putting it in a safe so you can't get hacked.


1

Webcams aren't supported in MultiBit. You can however paste a QR code using the 'paste' button in the side bar. You can also drag and drop an image onto the existing QR code in the side bar.


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