International Obfuscated C Code Contest – 2018 Winning Entries | Hacker News Reader

International Obfuscated C Code Contest – 2018 Winning Entries

ioccc.org

276 pointsmatt_d53 comments

Fabrice Bellard (the wizard behind FFmpeg, QEMU, etc.) has his own entry, which I find amazing: a ~4 kB program that outputs a ~50 kB image (of Lena), in addition to being able to decompress other images. His entry's hint page: http://www.ioccc.org/2018/bellard/hint.html

Here's the default output (embedded 1220 byte 128x128 Lena picture) of Fabrice's IOCCC entry converted into PNG:

https://pasteboard.co/Hk60KEv.png

Of course there are plenty of compression artifacts, but very impressive for just 1220 bytes of image data embedded in decompressor written in C totaling only 3984 bytes of source code!

No idea about what kind of service pasteboard.co is, hopefully the image will stay up for a while...

Edit: For comparison, here's a roughly corresponding original Lena image converted into 1269 byte 128x128 JPEG.

  convert -resize 128x128 -strip -quality 12% lena.png lena.jpg

https://pasteboard.co/Hk67yXC.png

> No specific obfuscation was needed as the algorithms already have a significant complexity.

Hehe...

He wasn't joking: http://www.ioccc.org/2018/bellard/prog.c

Funny, the compiler seems to have a hard time with it. Running it OTOH is instant.

It's a 3KB decoder and 1KB of image data, from the hint: "The actual image data is 1220 byte long, which gives a compression ratio of 40"

Can you explain a bit more how this works? I am not familiar at all with these challenges

50kB to 4kB is a 10x compression, it doesn't seem that huge, what's the achievement here?

From the author's comments:

"The uncompressed image is 12 times larger than the source code of the program which includes the image data and the complete decoder. The actual image data is 1220 byte long, which gives a compression ratio of 40. Using a JPEG-like algorithm would not be enough to reach this level of compression (the Lena image would be barely recognizable). So the algorithm is based on the latest advances in image compression."

http://www.ioccc.org/2018/bellard/hint.html

Achieving 10x compression in a 4kB program+data file hybrid is pretty hard to do.

From the author’s notes:

> The actual image data is 1220 byte long, which gives a compression ratio of 40.

Those 4k include the decoder source code and the C string representation of the image data

For those using iTerm, a nice way to try this out is running it through imgcat:

  make && ./prog < lena512.bin | imgcat

If you have ImageMagick installed the `display` utility can also show PPM images from stdin:

    ./prog < lena512.bin | display

---

btw, the `animate` program can also be used to display the animated GIFs from endoh1.

Is there a program available somewhere to generate our own compressed image (.bin) files?

Almost certainly not yet. The compression method seems to be pretty advanced, borrowing ideas from h.264 etc. and is almost certainly incompatible with any currently existing format.

If we're lucky, Bellard might eventually post an image compressor program on his website at https://bellard.org/.

GIMP?

Didn't he come up with a custom image compression scheme? Or am I understanding this wrong?

You understood correctly. This is a custom format that has some ideas from h.264 and who knows what else.

It might be custom. I haven't checked or compared. There are options to save images in other formats with GIMP.

Christopher Mill's "Best of Show" pdp-7 emulator is seriously impressive. How is this even possible in such a small program?

An IOCCC Judge here. We are rather fond of this one. The "prog" variant allows you to build and run the mullender entry from the first IOCCC http://www.ioccc.org/years.html#1984. The source is provided in the image, as is the compiler.

The source code is a punchcard...

http://www.ioccc.org/2018/mills/prog.c

Anyone able to decode what is "punched" into it?

  > # There is no 2016 IOCCC contest
  > # There is no 2017 IOCCC contest

Anybody know why?

An IOCCC Judge here. Sure, a variety of things! A competition can take about 4 full weekends of time ~128hrs total (Fri:6+Sat:16+Sun:10 x 4) to set up, judge and release the results. Getting 3 independent and very busy people coordinated with work, travel and major life events going on can get quite difficult. Recently we've opted to not start a competition if we do not pre-schedule the weekends for completing it! The result is that 2016 and 2017 could not happen.

Thanks! And thanks for taking the time to organise these competitions when you can, they're truly edifying.

poikola:

    X enum  {T,F}  z; //True & False

    #define E {
    #define B }

Old ideas, but they'll still catch people out.

It's interesting to see how well, or badly, the syntax colourization in NeoVIM copes with the various entries.

Yang's spoiler.html is actually super interesting as it's a live coding session for the entire program essentially. Also I thought the program name looked familiar when it said nuko, it's from the manga/anime Shoujo Shuumatsu Ryokou. It's a cute little thing that likes to eat technology, looks like this one's eaten four programs!

Don Yang provided a video of how he wrote the code and transformed it into the obfuscated version (see spoiler.html). It is as interesting as the final result itself.

Yusuke Endoh's "Best Use of Python" entry is a memetic masterpiece

Anyone else feel that their URL should be cocic.gro ?

hugged to death?

I have tried navigate the page, but I still have not figured out what the goal was this year, who won, with which program and what has been obfuscated in it. Is there a better summary of this contest somewhere? Is there a link I'm missing?

Goals: http://www.ioccc.org/2018/rules.txt

Who Won?: http://www.ioccc.org/2018/whowon.html

Guidelines: http://www.ioccc.org/2018/guidelines.txt

rules.txt contains rules and the overarching goals of the IOCCC, not the particular theme/goal for this year, and now I've wasted a few minutes poking through it to make sure. Thanks a lot.

I don't think there are any "goals" to the IOCC beyond writing the most clever and obfuscated code. There are only rules limiting what's acceptable.

You pointed me in the right direction, thanks! I was confusing IOCCC with the Underhanded C Coding Contest, which does have a goal / theme.

http://underhanded-c.org/#summary

Are you perhaps thinking of the underhanded code contest?

I am! Good catch, that explains my confusion. :-)

Everyone's a winner! :)

http://www.ioccc.org/2018/whowon.html

The page / site really needs a redesign and a bit of writing done.

I'm actually of a mind to start a new webpage that does just that, but there might be some copyright issues there.

> Creative Commons License. This work by Landon Curt Noll, Simon Cooper, and Leonid A. Broukhis is licensed under a Creative Commons Attribution-ShareAlike 3.0 Unported License.

Should be fine, no?

I'm not sure what copyright issues (writing or code or?) you are concerned about, but you should be able to get around them with a little planning. Just don't outright copy stuff.

Or just get in touch with the people behind the site and ask for explicit permission. Seems the simplest way to be sure, no?

"It is easier to get forgiveness than permission." -- Words of wisdom from a career bureaucrat.

I think the simplest way is to just set up a site and make sure you cite your sources. The site under discussion here would be a primary source and should be listed as such on every single page that references any of the data found there.

Beyond that, it really depends on what the GP intends.

Start a blog and write a little blurb about each winner as separate blog posts? I don't think any permission is needed. Just write whatever you want to say about the project and note that they are the winner listed here and link to the page where they are listed.

Start a clone of the site that adds additional info? Yeah, you maybe need to go talk to folks and find out if they are okay with that and get it in writing.

An IOCCC Judge here. Do you want to volunteer? What do you have in mind? Please contact us at j.2018@ioccc.org and include "IOCCC 2018" in the subject line. Thanks!

Not GP, but if you put the whole website on a git repo people can contribute easily (I can somehow imagine you may not too keen on handing things over to Github or something centralised like that, but surely you can have a self-hosting option)

right at the top are a couple of links like rules.txt and whowon.html, those might explain a bit more

And they say Perl is unreadable

Funny enough, the creator of Perl's previously well known accomplishment was winning these contests pretty much any time he cared to join. Take that as you will.

You know this competition is old when they still use .text files

Stuff that works doesn't need fixing.

It's very liberating, when you don't need to chase a trend.

The trend of three letter file extensions has been around since about 1989?

I'm more used to .md or .markdown, but apparently .text is also used for markdown files. Picking .txt (which I assume you're hinting at) would not be the most specific choice here.

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