 Hello and welcome to this podcast from filmsbychrist.com. That's Chris of the K today I'm just gonna be talking a little bit about qr codes if you're not familiar with a qr code is it's one of the many different types of 2d barcodes if you're familiar with barcode Like you buy when you buy products. There's usually what's called a UPC code, which is a standard for a type of barcode That's a 1d barcode it's it's read straight across and it can hold not only numbers but letters as well so you can put words in there But it's very limited like a barcoded pretty much the length of a sentence where these 2d barcodes that which are read Usually in a square or rectangle of some sort qr codes are very common and there's one of many like I said There's another standard. That's very common pdf 47 I think it is Which has nothing to do with pdfs as in portable printable port department document files portable or portable portable document files I think a qr code and these PDF I think it's 47 pdf 47s and there's a few others pdf 47 is the one if you look at least in the US here If you look on the back of your driver's license, there's a qr code not qr code, but a 2d barcode. That's a pdf 47 let me let me double check that it's a PDF PDF 417 is what it is and You can store a lot of data in these and I found it funny I don't know. I would say probably six seven years ago I was talking to a buddy of mine at work and he was talking about how qr codes are everywhere And his wife is a teacher and they're using them in the schools And he's like we need to stop using them or we're gonna run out and I laugh because that's kind of a silly concept of running out of qr codes and The reason for that is it's like not like there's a certain set number of qr codes But it's the data they hold and you gotta understand is that they can hold different lengths And also depending on what data is in there whether it's just numeric alphanumeric I think you can even put binary data in there the the number of characters can vary But if you didn't basic alphanumeric with you know characters like periods commas question marks, you know basically what you would have on your keyboard a Tiny qr code can hold almost five thousand characters And if you think of that in like terms of words on a page You're looking at like a page or at least a couple of paragraphs worth of text in each qr code And that's if you use the qr code to its fullest you can have different size qr codes as well you can have one word two words three words, you know and So and you think about all the books in the world and Let's say just one paragraph Worth of data in a qr code think of all the different paragraphs and all the different books And how there's all these different books and none of those paragraphs are identical So basically you can put all these different you're not going to have the same combination You can put every written book I would think not the entire book but a paragraph from each book into a qr code never have a repeating You know qr code and you still wouldn't use them all up and that's writing stuff that makes sense Not just randomly generated characters So the concept that we would eventually run out of qr code in fact I just looked it up. I was gonna try to do the math and like I said qr codes can vary in length depending on Obviously the size you put into it, but also the type of information being put into it But I googled how many unique qr codes are possible and I wish that I could say this number for you basically it's It's two point a very long number times 10 to the 4515 different ways so let me let me uh I Come in here and put this I'm going to quickly put this into this and so it's It's two point and then there's 52 digits after that to to the 10th power to times 10 to the 4515th power that's how many different possible combinations of qr codes are possible on the largest size of qr code which is a 177 by 177 square qr code so qr codes are not going to run out They're fairly standard, so they're gonna be around for a while I want to say that they're not gonna be replaced with something better in the future But think about how long just standard barcodes have been around Since the 70s at least maybe even the 60s. Let's see. Let me do the quick search here Wikipedia Barcodes and there's different standards of barcodes too, but let's see barcodes and Let's see if there's a year in here somewhere 1960s it looks like or let's see barcode was invented in 1952 so they've been around for a while and they're kind of antiquated They're kind of not nearly they can't hold nearly as much data as a qr code the same size Still very useful still around qr codes are great In comparison you can literally put binary data in there or even though it's plain text You can put base 64 data in there and even start like images and stuff and actually while I was looking up something to do this talk I was looking at the Wikipedia page For qr codes and I actually learned something that I didn't know about them now I knew that nfc near field communication you can make a tag or a chip that When you get your phone near it if you have nfc enabled it can open up a website Which you can do the same with qr codes In fact most qr codes you'll find out in the wild are in advertisements that are URLs but something that nfc can do as well is you can have the information for a Wi-Fi network so you could have one of these tags somewhere and people can put their phone near it and it will give the phone the Information to log on to the local Wi-Fi well turns out qr codes can do that too It's just a matter of typing out some plain text and giving it information a certain format Which I love when things are written in plain text because I can read it I can type it but basically it's just plain text. It says Wi-Fi Colon s and then you give it the SSID Semi-colon t colon and then whether it's WPA or WEP And then you do a P for password H for hidden or for if the Wi-Fi is hidden true or false I made one of these qr codes using qr in code in my Lenox shell scan it and sure enough Just the default camera app on my Motorola phone here Showed it as a Wi-Fi So and it asked if I wanted to add this Wi-Fi network to my phone So you could have a qr code by you know the front entrance to your house So when you have visitors you can be like oh just scan that qr code which most people it's very simple to get a qr code you There's qr code scanner In fact, there's JavaScript libraries so you can have a Reader in a web page. There's also qr code Generators that are in JavaScript so you can read and Encode qr codes right in your web browser, so you don't even need to install anything But a lot of phone like my phone the default Camera applications if it sees a barcode or a qr code it scans it and puts a little Icon up on the screen. I can click and it will read it and detect what type of qr code it is based on the formatting Unfortunately a lot of people don't even realize they can scan qr codes Even though they have a phone that's a scanner in their pocket all the time anyway these qr codes I just want to talk about them because I I love qr codes They're so useful and I just wish people would use them more and they are going to be around for a while So, you know if you haven't played with qr codes, I definitely recommend it if you want to generate your own you can use qr in code which is Should be in the package manager for pretty much all Linux Distros install that I have tutorials on it, you know You can search films by chris.com search qr code. You can have it generate a image such as you know a PNG So you can save that image somewhere for use in something. You can also have it output in a Unicode or ASCII characters right there in your shell So you don't even need a GUI interface to generate them and then if you want to decode them on your Linux system Zbar is a great application that can scan things live from a webcam Or you can pass it a image file such as PNG JPEG whatever and it will give you whatever Codes around there and it scans not only qr codes But standard bar codes as well and there could be multiple on a page and we'll list them all out So I definitely I just want people to use them more And actually I'm going to talk about them more in the next talk when it comes to like corporate use of them So yeah, check that out. I hope that you subscribe to my youtube channel I'll support me over on patreon.com forward slash metal x1000 if you are a supporter You know that you get these podcasts and all my videos early and available for download I thank you for watching and as always I hope that you have a great day