There is a video on Youtube explaining some image formats. At the end of the video, QOI is mentioned as well. Check this out
https://youtu.be/EFUYNoFRHQI
Yes =) both @tom_ and @mattigames are right. I'm not a native English speaker, pardon my English usage. What I mean is, this guys achivement shows his self-motivation, dedication and knowledge level at a relatively younger age. (Maybe for some, he is old enough.)
I'm not even an engineer, and I have made one. But, making a 3D printer by yourself from ground up (or assembling one with the parts bought from china etc.) takes a lot of time. I only paid attention at my spare times, so it took my months. But I must say that, it is a very satisfying hobby. I strongly recommend it :)
But if you want to buy one, you can find very nice 3D printers at $250 - $300 range from aliexpress etc. It may take hours, a day or a week for calibration (depending on your printer model and printed part quality expectations), and you are good to go.
But I must say that, 3D printers need maintenance and that can take your time as well.
If you want to educate yourself, http://reprap.org/ is the site you would want to visit. Not only for making your own printer, but calibrating and maintaining a bought 3D printer as well...
The code looks like the ones from C64. I used to write C64 Basic when I was 5 to 10 years old. (Later my father bought me an Amiga 500 and I started to play around 68000 assembly with MSeka assembler. There was also a C compiler, but there wasn't any documentation about C and the libraries. So I didn't choose to learn C with trial and error. Also there wasn't any Internet... Assembly was so much easier and logical to me at those days.)
But at some time, my C64's tape recorder broke. And I couldn't save the programs I wrote. So, programming to me was, waking up in the morning, start writing some program and playing with it, and in the evening when I switched off the power button everything would be gone. But I loved to play with my C64 :)
At those days, sometimes I even wrote very long programs. But I must admit that, when I see those 322 lines, it really frightened me now! It's looks like a million line C or Java codebase to me. I have no intention to refactor that code at all.. But I agree it would be fun.
I wrote a Microsoft Excel macro (yes, it's VBA) when I started my current Job at 2008. It only converts badly formatted txt output of mainframe to an Excel file. Just does it only, but does it well.
I'm very amused that even today people use my macro and thank me for writing it.
But, I think judging a language (which claims math and scientific computing is it's strongest point) by print screen performance is not fair.
And, the authors last example is a little bit misleading I think. The C code sets up registers and jumps to the main sprintf routine. I don't know why didn't he tell that routine's instructions count...