Topic: How would you like to design a bitcoin banknote? - page 10. (Read 94820 times)

point me to a link that generates those with a unique private key... (wallet)

I've put together an offline note generator:

https://github.com/salfter/btcnotes/

Notes are rendered four to a page.  Five denominations (0.5,1, 2, 5, and 10 BTC) are currently supported, each of which prints in its own color.  Addresses and private keys are generated on-the-fly, rendered as both text and QR codes.  Page layout is done in PostScript with artwork that started out as SVG, so you get the highest print quality possible.  For convenience, final output is to PDF.  I considered using HTML and CSS to position SVG images directly, but print quality proved a bit hit-or-miss...Firefox was usually OK, but Chrome frequently rendered SVG elements at 72 dpi or so before printing.  Even with Firefox, I sometimes had some unexplained print failures.

For sample output, try this:

https://dl.dropbox.com/u/57535575/job2948.pdf

Next time I revisit this image, it needs to have some color bleeds so that minor variations in cutting don't result in white stripes along the edges.

If someone else beats me to it, please add bleeds.

Another possibly useful bit of code that creates QR codes in SVG format:

This depends on netpbm and qrencode.  Basically, what we do is create a QR code PNG, convert it to a PBM text file, and mangle that with an awk script (an admittedly naive script, but it should work for addresses and private keys) into an SVG file.

First, the awk script, which we will call pbmtosvg.awk:


It reads the dimensions out of a PBM text file, then writes a grid of black and white rectangles into an SVG file.  To use it, try something like this:


Some examples:


1JzFx4iQqnpyBaQbjfZ9Tg2u4KzkSpTDzi


5HzQEdP55SGjBawGCw25A14FcjegFyPtbn3xhzb1rhpxX5dZcc4

You can then merge these with one of the SVG note designs already given however you want. I'm thinking a little HTML file with some CSS positioning info should work to overlay QR codes (and, optionally, text) over a note.  By keeping all images in SVG format, your notes should print at whatever resolution your printer can deliver.

Maybe this is a bit much like hammering a square peg into a round hole, but after messing around with Inkscape for a bit, I couldn't find an easy way to change the overall color of an SVG file (such as what several of the banknote designs posted here use) with it.  Since SVG is just a bunch of text, it's not much work to use standard command-line tools to do most of the work. 

First, grab a file you want to edit.  For this example, I'll use graphnote.svg from https://casascius.com/graphnote.zip.  First, we need to extract the colors used:


You may want to remove black (#000000), white, (#FFFFFF), and any grays (#666666, etc.) from the list.  Doing this with graphnote.svg produces 13 distinct colors.  Next, make a swatch file:


Next, load the swatch file into the image editor of your choice and adjust the colors.  I use the GIMP.  First, you'll want to select Image -> Mode -> RGB to enable the color editing we want to do.  Next, select Tools -> Color Tools -> Hue-Saturation... to tweak the colors.  Make sure Master is selected as the color to adjust, then use the hue, lightness, and saturation controls to shift the color swatches to something you think will look good.  To make a green bill out of graphnote.svg, try setting hue to 70 and saturation to -15.  Save the result back to a new PNG file (e.g., graphnote-70,0,-15.png).

Now we need to read the colors out of the edited swatch file:


Finally, we can use the original file and the two color table files (the text files generated) to create a new SVG in the desired color:


You will then end up with something like this (if you don't see a green Bitcoin note below, your browser is out-of-date and needs to be upgraded):



Repeat all but the first two steps to produce notes in however many colors you want.

I really like the design and I have printed several notes, but I have a suggestion. The value of the note is hard to find. I would like to suggest that the value be displayed prominently in the corners. In addition, the size of the value in its current location is too big for the space, so I would like to suggest making it smaller. Here is an example:

Thank you so much Where do I send the .25BTC??

https://casascius.com/billbackno.pdf

I am using RobKhor's printcoins project. It is online at http://print.printcoins.com. I don't use the online version. I downloaded the project to my off-line bitcoin machine (Raspberry PI) and I generate the bills on that. It's completely offline. It takes a while to generate on such a low powered machine but I don't have to worry about it being comprised.

I generate vanity addresses for my coins. "1BTC....", "1Coin....", "1Half....", 1ooBTC....", etc.

I added BitPay's Leonardo note to Rob's project and it is now part of the main project on github.  I also added a turning note from another project I found made by aristus.

I have since talked to Anthony (?) at BitPay and he sent me the layered images for his notes so the one I'm using now is slightly different than the one in the printcoins project. I intend on adding it to the project soon though because I think it's prettier.

Additionally I will be adding the bitpay "bond" but I have not come up with a design modification I'm happy with yet.

My hero too. I remember when the first round of Casascius coins went out with a typographical error...the response of some of the less useful among us really ticked me off...

Well done again sir. Well done.

I don't have adobe illustrator. I have a macbook pro as my main computer. I don't have photoshop but I do have gimp.

I have a feeling blockchain.info or weusecoins.com wont' go away ever but you never know. Websites have a tendency to turn into cobwebs in the long term and my customers seem to hoarding long term. That said I like having both of those domains in the text. The only one I have an issue with is the bitaddress.com address since this information is not going to help the buyers of my paper coins and instead confuse them.

If it is trivial to make a change, I think that one of the following quotes  would be great in place of the text "Print more of these: bitaddress.org". I'm willing to donate .25 BTC for this change if you make it casascius.

Number 1 choice: "Store in a safe dry place"

Other choices which I would like in no particular order.

"Join the revolution"
"Bitcoin, an idea worth spending."
"In cryptography we trust"


I completely agree with you. Us geeks take so much for granted. Most of us do not understand how people have a hard time buying/spending coin. It seems so simple to us. Not to them though.

I did this in Adobe Illustrator.  It is nothing more than a block of text (which I repeated with cut-n-paste) and then warped with a 1x1 mesh envelope by skewing two of the corner points.

If you load the PDF in Illustrator, it will still recognize its own objects natively, including the envelope.

The font is Ubuntu, freely available, just google "ubuntu font".  It's also in the zip file of my https://casascius.com/btcaddress.zip because it's a dependency of my note generator for Windows.

If you don't have access to Illustrator, I would be happy to make trivial changes to it and send it along.  Do you have an online generator for your notes?  I'm just curious to see it.


Aww, thanks.  I just want to get Bitcoin in the hands of the computer illiterate and non-computer-enthusiastic, and I see this as the way to do it.

Casascius, do you have a layered image file of this design? (xcf, psd) and a copy of the font used?

I really like it a lot. Since I am using a modified version of the BitPay design with my notes, the "print more of these:" portion would need to be changed for me. I have nothing against bitaddress.org it's just that my customers are paying a premium for printed coins and bitddress.org does not offer the desgin I added to RobKhor's printcoins project.

On a side note, Casascius, you are one of my bitcoin heroes because of the physical bitcoin implementations you have followed through with.

This is quite nice. I don't use the pay design but these look great on the back of any design!

Nice!

Very cool. Do you know who runs blockchain.info?

Check out this printable back pattern I made: https://casascius.com/billback.pdf

This is a good idea, just print the pattern on one side, pop it in the printer again and print the bills

While I agree with 100% of what you are saying I think that the 'throw away' blank back is an opportunity for education.  Assume we had a good repeating pattern with the bitcoin logo and WeUseCoins.com at a diagonal (think the sponsor graphics behind people at press conferences).

You hand a bill to someone and they ask (WTF is bitcoin?) you can flip it over and they have all the info they need.  It is also very easily customized for each person printing but doesn't tie a bill design to any given site.  You could even use a mixture of sites if you wanted.

Another benefit to this approach is that it would be very easy to print if designed to either: 1) fill an entire sheet, or  2) just be bigger than the bills themselves.  Then you just trim the bills as normal and don't have to worry about the background.

In fact there could even be a tiny opportunity to provide pre-printed linen paper for those who want to print there own bills.

Hey, I just wanted to say, you're totally right.

I printed a bunch of these out on good 100% cotton paper and they are perfect. Now that I've actually used them a few times, I see the value of making them look nice but not too nice. Having designs on both sides is overkill. They are just about perfect -- it's no big rigamarole to print them, you don't feel bad writing on them, and they are durable enough for you wallet (on the cotton paper) but they still feel like single-use coupon style notes.

So glad to have these. Thanks!