/tech/ - Technology★

S N O W C R A S H

convert input.gif -type truecolor -depth 8 +matte tmp1.bmp
head -c 138 tmp1.bmp > tmp2
cat archive.7z >> tmp2
dd if=tmp2 of=tmp1.bmp conv=notrunc
convert tmp1.bmp outputimage.png

>blur-aware color orde

how does that work when the camera moves vertically or diagonally or slightly up because the user's hand is shaky

>>983629

they expect the blur to be one-dimensional.

Any methods that can save a high volume of data without the annoying process of being "scanned"? I'm thinking like punchtape or something, something physical which you can just conveniently feed through.

>>983619

Why not convert it to base64?

>>983773

"Scanning" is for the mobile age, and it also have use for archiving with Paperback

Tagging the streets with QR code is basically /pol/'s passtime (see https://twitter.com/ahundredhands)

> Base64

FIle embedding is about hiding data in weird places for times when a website only accepts images, videos, audio and such. See >>983624 for YouTube

Challenge 1: bash script that hides data in EXIF/*IFF metadata blocks, or even MKV/MP4 metadata blocks

Challenge 2: hash visualization similar to hashblot and polyhash

>>983571 (OP)

>Master/Slave Symbols

UGH!

>>983619

>But has anyone tried to make our own brand of QR code >>983583 ?

Translation: I'm too stupid to make something, someone else please make it for me!

>>983583

>Why can't 8chan make its own barcode?

Just for fun? Or do you want to solve a real problem? Making 2d barcodes isn't difficult. Making something more useful than existing solutions is difficult.

>>983994

> Just for fun? Or do you want to solve a real problem?

Just a FOSS version of a circular/annular/dart barcode, because it looks good for sharing PGP keys, IPFS/Torrent hashes or hyperlinks.

The Messenger code looks pretty obvious with 4 "eyes" 90 degrees apart for position/alignment, but we don't know where the timing patterns are.

The Kik code is even weirder as there is no position/alignment pattern or Timing pattern.

Snapchat's code (non-annular) looks pretty arbitrary with the logo, the format is static and scanning is easy, adapting it for 8chan or some other project would be sweet.

>>983571 (OP)

There's a reason why color isn't used for printed barcodes because blacks are cheap.

>>984602

negligible cost and phone-to-phone data transfer makes it easy to use color barcodes.

>>984604

First of all, cost of ink amounts to millions of dollars. Second, color printers have quadruple the complexity and failure rate of black and white printers. From which follows the third, color printers are vastly more expensive to operate.

>>984614

Firstly, if you have the money to print colored posters, the side cost of colored barcodes are negligible.

Second, you have not answer the phone-to-phone or screen-to-camera data transfer question.

>>984602

>cheap

Printers are garbage and produce vastly different color results, cameras are garbage and produce vastly different color results, time is garbage and changes printed colors over time, the whole idea of using color as scannable information is a bad idea.

>>984625

Ah and let's not forget how ambient color (daytime, surrounding materials and colors, etc) change the way things look.

>>984625

>Vastly different color result

When you only use primary and/or secondary colors it becomes negligible

>cameras are garbage and produce vastly different color results

Ditto

>time is garbage and changes printed colors over time

Then you are printing on the wrong type of material in the first place

>ambient color

Color adjustments, people, it is EASY (especially with phone camera lights)

>>984629

>When you only use primary and/or secondary colors it becomes negligible

If you do that then the cost of ink is definitely less worth it. It'll probably be a better idea to use shapes rather than colors. For example I imagine you could change squares into horizontal & vertical lines pretty easily.

>>984630

> change squares into horizontal & vertical lines pretty easily.

And that is how you reduce data capacity of a barcode! Well done, faggot!

Seriously, standard line barcodes have been around for decades with shit capacity, then >>983579, >>983582 and >>983583 came and nothing is the same ever again

>>984634

>And that is how you reduce data capacity of a barcode

Squares = pixels in the QR code or whatever. Rather than just reading whether it's black or white, you also check whether the pixel is tall or wide.

>>984635

increases unnecessary complexity, and the tradeoff is that you have to make larger prints to prevent print blurs.

>>983583

Thirty Kikcodes as example!

https://my.mixtape.moe/ewwpgz.zip

Now, all we need is to find which patterns are used as position/alignment pattern

>>985002

https://my.mixtape.moe/iajgen.zip

There, 100 examples sorted by resolution. Surely you can make something outta this

Bumping this for fun

2DPD

>>984626

also uncalibrated screens lol

>>984625

>>984626

That's why you put a calibration region on the image.

I was thinking of making a small 2 hour project where you could encode strings into small images that would be made up of 1x5 "tiles", representing 5 bits/32 unique characters,

00000 would be a space obviously

00001-11011 would be the characters of the alphabet

11110-11111 would be 5 extra special characters, the ones i have in mind are ",", "-", (apostrophe), "?", and "."

I'd have the decoder two commas into a colon, a comma and a period to a semicolon, a comma and a hypen to a to an exclamation mark, and two hypens into parenthesis.

This is fascinating. I've always wanted a means of storing data on giant tapes of some ridiculously strong material that could stand the test of time and be simple enough to implement on SBCs.

>>986229

No. That is not creative

https://en.wikipedia.org/wiki/PDF417

https://en.wikipedia.org/wiki/Code_39

https://en.wikipedia.org/wiki/Code_93

https://en.wikipedia.org/wiki/Code_128

https://en.wikipedia.org/wiki/Telepen

bump

CQR code-5, CQR code-9 and HiQ codes FTW

https://pdfs.semanticscholar.org/95c7/fe455a084b0f0ce9923e996652156c1f7998.pdf

https://arxiv.org/pdf/1704.06447.pdf

https://www.researchgate.net/publication/313674473_CQR_CODES_COLORED_QUICK-RESPONSE_CODES

http://home.ie.cuhk.edu.hk/~hlxu/papers/TIP2018.pdf

>>986229

Baudot code or ITA2.

There are numerous protocols currently in development and they all have unique abilities. One is even challenging wireless protocols like NFC in terms of throughput. The main thing is being able to decode with a 99%+ success rate in ANY lighting. The next few months should be interesting, I mean, serving data off your screen like its some kind of antenna, that's freaking sweet. Good luck fellow developers, let us make this a good run. - JP

>>988443

https://jabcode.org/