Bitcoin Forum

Basics
A program called PaperBack (http://www.ollydbg.de.nyud.net/Paperbak/)(Win32 at this time, Open Source'd) allows a user to encrypt and  print a paper copy of a file, to restore the file you scan or provide a image of the printed paper and it dumps out the file

How to use with you wallet.dat
1) Download PaperBack from the location provided before
2) Open PaperBack
3) Open Options and select the options you wish to have (For more info, read the page provided above)
4) Drag and drop the file (wallet.dat) into the window for printing
4.5)File -> Save to bitmap, It will ask you what file to encode, and then where to save the bitmap

Restoring your Wallet.dat
1)Scan or provide the bitmap of the backup
2)Wait for processing
3)Save wallet.dat

Example
(Due to me not having a printer, I had to kinda fake it)
Here is the first Image: http://imgur.com/8b7nz (http://imgur.com/8b7nz)
Its a empty wallet.dat with Encryption on (AES-256), standard options past that
Here is the damaged copy, Opened in GIMP saved as a JPEG at 4% Compression, then converted back into a Bitmap
http://imgur.com/nKKLO (http://imgur.com/nKKLO)

ECC had to correct 56bytes of bad data.. once decoded the md5 hashes where the same!

Here is a screenshot asking for the password (The password is "bitcoin")
http://imgur.com/OEj6G (http://imgur.com/OEj6G)

Extras

Found this while googling around,

http://ronja.twibright.com/optar/ (http://ronja.twibright.com/optar/) Its GPL'd and seems to be better for data storage and recovery, but I hear its harder to use

what problem do you see this solving? just curious.

its just another form of backup :)

I've backed up some private keys to paper in the past, and found it very useful when i had to go and recover them

If the wallet.dat isn't located on a hard drive or memory it cannot be used by anyone.

The piece of paper can make the wallet.dat appear from physical to digital.

I like this.

I guess for long term backups it could make sense.
a file still exists on disk after you delete. it is only gone when new data is written over it.

Low level format takes care of that

a file still exists on disk after you delete. it is only gone when new data is written over it.
[/quote]

I think a lot of people know that.

certainly. but that seems a bit extreme. lets not give anybody any ideas ;)

not saying a physical copy isnt an interesting idea, but i think an encrypted thumbdrive would serve the same purpose.. or maybe always reading/writing to a tape drive if you really want to eliminate any trace from your machine.

most dont actually, but thats not the point. we are talking about turning something that is on disc into something physical that can be stored and then read back on to disc. no way around it, its still there unless you go through the trouble of manually flipping the bits.

What about this, you print your wallet.dat and store it, and print the method of reading it

30 years down the line (BTC is still around) your kids find it, and wish to decode it,

Paper last longer then most digital medium at the moment

this is probably how i would utilize it, but i suggest also storing a copy of the program somewhere to reread it. it would be a total bummer if 30 yrs in the future the software is long gone. :-\

if you download the source, and if your any kind of programmer. decode.cpp seems simple to work with print that thing in plain text

id suggest adding this to your howto just in case. this is an interesting idea for a sort of alternative bitcoin savings account.

Agreed. Very cool.

edit---

So in 30 years people have to still be able to run this program or could it still be decrypted as long as the passphrase is known?

Only if it supported by the new OS
:P


But, this is actually a good idea. I would keep one on a flash drive and another on paper. Digital data can be damaged easily, so having a paper backup in the same location wouldn't be a bad idea.

Thanks for sharing this!

Remember, flash drives are almost a pain to delete things from.  The technology that protects cells from repetitive use also keeps security programs from effectively overwriting data....

But honestly, it's safer then holding cash.. . and if you want to hide it from the IRS.. . this maybe the next best thing lol

Interesting idea.

Say, where IS the wallet.dat? I just downloaded bitcoin and am trying to learn and have been looking for a couple hours for an answer - all over the wiki and here and on my computer, too - can't find wallet.dat.

I, of course, have no bit coins yet - will I get one if I can figure how to get a coin? Thanks and sorry for being a dumb n00b. I'm not computer illiterate by any stretch but this one got me good.

Pretty cool but id end up losing the paper that i saved it on.

wallet.dat can be found in these locations:

Windows:
%APPDATA%/Bitcoin/

Mac:
~/Library/Application Support/Bitcoin/wallet.dat

Linux/Unix:
~/.bitcoin/wallet.dat

I made a interesting post about this a while ago, and it's buried now.

See http://forum.bitcoin.org/index.php?topic=1705.msg42765#msg42765
 (http://forum.bitcoin.org/index.php?topic=1705.msg42765#msg42765)

Thanks for the guide!

I thought this was something new, only now to find out this had been around for so many years. lol

 Great ide and I was going to try this out but then I thought,

`If I print to paper then I need the source to read it again. If I'm printing to paper for longevity ten I need to store the source for how to read it as well`

 And that's the thing -will the program to decode it still be available in 30 years time? I suppose I'd write a note with it giving as much info as possible, perhaps even the sourcecode too...  but then you might need to skill/effort to compile it. That might be possible, certainly if there's lots of money involved... but I can see myself getting frustrated with it. Perhaps if a very basic structure was saved with it as to how the data is encoded.

 Only a couple of years ago I had some stuff on cassette saved from a Commodore Plus4. In that case I could have searched the community for info but in practice I couldn't be bothered. That's the thing, we don't know how much it will be worth the effort in the future.

 It's a good point though, media types. Isn't there a more mainstream solution? Like double archive quality CDs?