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gifplus
I'm crying. I always wanted one of these. I'm so happy.
samet
Very clever hack.
eslachance
That's pretty amazing, and it's really too bad that this technique wasn't actually available years before... (or was it?)
old_sound
It always was actually. I even tried this on IE6 and it works
DougWebb
I wrote the first (only?) GIF decoder for the Commodore 64 back in the day, including displaying animated frames. There was no 'live' delivery of images back then though; you had to download them in-full over FTP or a proprietary file transfer protocol before you started parsing. I suspect the encoding was too slow on most computers at the time to stream the file as it was encoded anyway. But yeah, the basic capability was present back then.

Once the WWW kicked off and GIFs started being served, and especially once cgi scripts started being written, someone could have had this idea and the software and hardware probably could have handled it. So we could have been doing this in the late 90's. I wish I had thought of it...

Xosofox
GIF... that's soooo geocities...

Very clever

emp_
> sadly we are in mid September here in the northern hemisphere.

I am in the south and can confirm we are also in September, will report back with news.

/snark

delinka
I really hope this statement by the project author was intended to be funny (as opposed to a serious belief that there's another calendar for the southern hemisphere.) I laughed. And then I realized I know people who would find this epiphanic and insightful.
hds
Of course if we did add 6 months (mod 12) then we could have hot July (almost) everywhere.

And an australian christmas in June, but it would be worth it!

Evbn
It's discontinuous. To make this work, stretch the months (add/subtract days) so the tropics only have July August and poles only have Jan/Feb. Adjust holidays appropriately.
TomatoTomato
And you can add/subtract hours and minutes to days so that the sun rises and sets and the same time all year!
sneeu
See: Riyadh Solar Time.
jeza
We had a white christmas in Australia... in July! ;-)
SeanDav
The world is flat, didn't you know?
gavingmiller
Our Canadian office managed to convince a couple of team members in our American office that we ran on a 20 hour clock, with 72 minutes in an hour. That was fun for a week.
eru
Metric time!
kragen
As a remarkable coincidence, another hack that Ka-Ping Yee did once was writing a nonstandard clock for his Palm. He spent a summer living 28-hour days: six 28-hour days per normal week, going in and out of phase with the sun once a week. So he needed a way to remember when to go to sleep, when to wake up, when to eat dinner, and so on. When it's 25:00, what do you do? We have a lifetime of intuition built up around clock times on a 24-hour clock.

So he wrote a digital clock that used standard-length seconds, but 70 of them per minute, 60 of those minutes per hour, and 24 of those hours per day. So when it was 10:30:59 by his nonstandard clock, he was at the phase of his nonstandard day that corresponds to 10:30 or so of the standard day --- but the clock would then roll over to 10:30:60, 10:30:61, ... 10:30:69, 10:31:00.

It was very amusing to see people's reactions upon watching the clock for a little while, especially at the time of week that it was more or less in phase with normal time.

crisnoble
If realtime messaging is a new and cool thing, what were chat rooms back in the day? not realtime? Am I missing something? I don't remember needing reloading those pages...

All that aside, this is amazing.

ceejayoz
A lot of those used a periodically refreshing frame or something similar.
delinka
I don't necessarily think they intend "realtime messaging" to be the focus here. We've had obvious IM for years and it didn't exactly lull as far as I know. Definitely cool that someone hacked around to learn the details about some bit of tech to make it do something it wasn't built for. I applaud this attitude.

That said, it seems that since the "digital revolution" we go through these re-inventions of basic ideas and tools quite frequently. We've had "email" since the time multiple people could use a computer; recently, I commented on HN about how someone reinvented server log analysis tools to find click fraud (they were outsourcing analytics and apparently were unaware that web server logs ever existed.)

wallunit
Chat rooms 10 years ago weren't using web standards like HTML, GIF and Javascript. They were writing either in Java or in Flash.

However MSIE6 also supports XmlHttpRequest (though an Active-X Control), which you can also use for real-time communication. Just setup a XmlHttpRequest and let the request idle on the server-side until new data become available.

WickyNilliams
Wouldn't that lock up a thread, per request? Things would quickly grind to a halt I'm sure
GeneralMaximus
Depends on your web server. AFAIK, nginx uses a combination of events and threads to handle a ginormous number of simultaneous connections.

See:

    http://en.wikipedia.org/wiki/Asynchronous_I/O

    http://www.slideshare.net/joshzhu/nginx-internals
    
    http://www.aosabook.org/en/nginx.html
    
    http://serverfault.com/questions/86674/why-is-nginx-so-fast
Also, Node.js.

Edit: formatting.

wallunit
Only if your server code process each request in a separate thread. But that's also true, when using web-sockets or when using the GIF approach. When implementing real-time applications, you always have to write non-blocking asynchronous server code, for example using node.js or Twisted.
macca321
does it work in email clients?
dkroy
That is extremely clever, this just goes to show that if you know how something works inside and out you can come up with clever hacks.
jcfrei
hacking at its finest. while real life use cases are debatable the implementation is very, very cool.
fmax30
It would be much cooler if you were to send the video stream to the gif instead of the booring old messages. Very cool though. Just think if something like this with video was invented back in the days of IE6 , it would have been the skype of its day.
david927
HN's jacquesm did just that, and made a lot of money doing so.
whyleyc
Could you expand on what jacquesm did ? Interested to hear.
Xosofox
Combine this with a client side JavaScript based OCR implementation, and you could even send TEXT in real-time.

Imagine the possibilities !!11!1

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simonw
I've seen this technique once before... Ka-Ping Yee built a demo that did this back in 1999: http://zesty.ca/chat/

It's an awesome hack, cool to see it being rediscovered/reinvented after so much time!

old_sound
That's the chat I refer on the CREDITS. Thanks for the link I added you and the link there.
danellis
A friend of mine wrote a Citrix ICA client using this idea and a server-side image map, IIRC. It was actually usable.
sp332
For a while (they've changed clients a few times but it still might work) the last fallback of LogMeIn remote desktop software was a gif of your desktop in an image map. It was surprisingly usable!
TazeTSchnitzel
I've always thought of that, but never an animated gif. It seems brilliant!
gojomo
Also some early webcam/security-cam 'zero install' stream-via-web-pages used this technique, if I recall correctly.
jere
I am convinced HN is the Pinterest of software.

Someone made a coffee table out of old crates? Pin. Someone made a fence out of old wood pallets? Pin.

Someone made a realtime messaging library out of animated gifs? Upvote.

__alexs
Someone made a logic gate out of crabs? Ignore :(

http://news.ycombinator.com/item?id=3831987

Evbn
Wow, they found an even messier substrate than water!

... - transitors - vacuum-tubes - water - crabs - ...

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_suoiruc
This made me laugh. Perfect follow-up.

That's the way to get the good stories onto the front page.

andrewflnr
It's a hack. HN is for (among other things) news about hacks.
peterwwillis
It's not really a hack. It's slowly printing a GIF for a kind of really limited server push. If you want to send someone messages via server-push in an old-school way, use multipart/x-mixed-replace.

A hack would be taking the input of a TV tuner card, converting the video to .gif frames, and printing that out slowly enough to view a slow video over a DSL line to watch TV without a media player.

tcdent
Maybe not a great enough hack for you, but it's still a hack by definition; using something beyond it's intended purpose.
damncabbage
It's not really a hack. ... A hack would be taking the input of a TV tuner card, ...

No True Scotsman: Hacker Edition?

jaylevitt
No, a hack would be doing all that while building an abstraction layer around Google Calculator to act as a primitive CPU to do the GIF encode.
tylermenezes
It seems a bit arrogant to say "I don't like this particular article, therefore the community is primitive." An Animated GIF messaging library is certainly of interest to a majority of hackers.
jere
I didn't say anything of the sort.

I simply made an amusing (to me) observation. I had earlier thought Pinterest seemed like MacGyver for people into crafts (at least that's the kind of thing my wife kept getting excited about). That's not to disparage HN or Pinterest or MacGyver for that matter.

will_work4tears
As a die hard McGyver fan, I'm offended you'd compare him to a subset of stay at home mom's pinning pictures of other women with flat abs as "motivation." Ok, occasionally they post some pretty cool stuff, but mostly it is the former.
wisty
Someone wrote blogspam about how fences made out of old pallets are a bit of flash in the pan? Pin.
aggronn
Does this work on the iphone? I expect this would be a great alternative to socket.io for mobile that doesn't support websockets or flash.
majke
SockJS works basically everywhere.
arscan
This is awesome -- you never know when a solution like this might come in handy.

Wayyyyy back in the day (NS4, IE4 day) I used the width / height of an image the browser polled every few seconds as a transport mechanism... the only other option (refreshing a hidden frame) caused an irritating "page refresh" clicking noise. This was before XMLHttpRequest obviously and was enough bandwidth for our needs. It worked so well that I believe its still being used in production systems.

I haven't looked at the javascript generated in this animated gif solution, but I assume that it does some stuff that wouldn't work in the pre-IE6 browsers. It would be extremely amazing if it did though.

old_sound
This doesn't use any javascript
arscan
Ah, I just realized that this simply prints text out in a gif... it doesn't encode text in the gif and then decode it in the browser into text that javascript could manipulate. Too bad. I wonder if that's possible...
streptomycin
It is possible, as you can now get the raw pixel data of an image by copying it to a canvas and using getImageData.

    <img src="test.gif" id="img">

    <script type=text/javascript>
    var img = document.getElementById("img");
    var canvas = document.createElement("canvas");
    canvas.width = img.width;
    canvas.height = img.height;

    var ctx = canvas.getContext("2d");
    ctx.drawImage(img, 0, 0);

    var imageData = ctx.getImageData(0, 0, canvas.width, canvas.height);
    </script>
Then you can do whatever you want with the pixel data.
mmastrac
Unfortunately not on IE6, and this would require both canvas support and CORS. I think most browsers that support that also support true web sockets.
arscan
This would be a great step in some kind of rube goldberg inspired website.
xxbondsxx
Encoding data into images is certainly possible, albeit sometimes a PITA.
gfodor
Awesome. I did this trick too, many years ago. I stole it from Liveperson I think.
kragen
When we were doing Comet in Netscape 4 and IE4 at KnowNow (in 2000, although Rohit, Adam, and Peyman got the technique working in 1999), we used an endless HTML frame, which simply never stopped loading. We'd spit out a <script> tag whenever there was a new message to deliver. There was an annoying clicking noise in IE, but only when the frame did finish loading because you'd lost your network connection or restarted the server.

This eventually got open-sourced as "mod_pubsub".

riobard
There you go, Facebook's BigPipe!
dotborg
there is no client side code or am I missing something?

how do I decode my data from animated gif in javascript?

icebraining
You don't, it just displays the image.
dotborg
title is very misleading, on purpose I guess
richthegeek
I did something similar for cheap (insecure) desktop streaming a few years ago.

Roughly, use scrot (or similar screen capturing command line tool) to take a screenshot of the desktop and then encode it into a gif frame. Repeat once per second. Boom, your desktop is now a gif.

The main problem with this approach is that transmitting stuff via gif (low-color bitmaps, remember) is painfully slow even with modern internet.

That said, could probably be very useful in some instances!

dbaupp
It is possible to do some interframe compression with gifs[1], so one can potentially reduce the data sent significantly, especially if one is typing or not changing the whole screen. (And gifs aren't "just" bitmaps, they have some compression[2].)

[1]: "Some economy of data is possible where a frame need only rewrite a portion of the pixels of the display, because the Image Descriptor can define a smaller rectangle to be rescanned instead of the whole image." https://en.wikipedia.org/wiki/Graphics_Interchange_Format#An...

[2]: https://en.wikipedia.org/wiki/Lempel%E2%80%93Ziv%E2%80%93Wel...

eliaskg
Would it be possible to use <canvas> for extracting pixel information as binary data?
old_sound
I was thinking about doing something like that as well. To not send real images but some binary data. Dunno if it will work
masklinn
> http://ernestdelgado.com/public-tests/gifoncanvas/

Kinda:

> if we add an animated GIF as the first source, every time a drawImage call happens it will render whatever the status of the GIF is at that very second

So if you call drawImage in a (timeout/setinterval) loop, you can get the frame's data, compare to the previous frame's data and if they're different you got a new frame-worth of data.

Considering that requires canvas support (with image-query capabilities) you're probably better off using websockets and the like.

joezydeco
So when you read about countries like Venezuela installing proxies in front of Twitter before an upcoming election [1], is there a potential to use this technique to tunnel information into areas that normally would suppress it?

[1] http://orvtech.com/en/general/gobierno-venezolano-elecciones...

king_jester
This is pretty cool. I don't know if I would use this in production, as people with epilepsy usually disable GIFs to protect themselves, so this tech would probably fail (usually people use an extension or set the browser to only load frame 1 of the GIF and stop).
dllthomas
Also, I can't imagine it would play well with screen readers.
benwerd
First person to turn a 90s animated GIF divider into an actual live progress bar with API wins the Internet.
Phargo
Couldn't this be used to add another layer of security to a conversation? If there is a way to generate gifs on the fly that contained what you wished to say, it could be used to mask your message from basic text screening and copy/paste.

Thoughts?

dangrossman
Writing text onto an image is easy. Graphical hit counters are almost as old as the web. The first ones just lined up images with preprinted numbers on them, but as soon as CGI became popular, people had libraries to write the text on top of an image too.
andreasvc
It wouldn't provide any meaningful security; think of how difficult it is to make a CAPTCHA that is both readable for humans and hard to beat for computers. Adding security to a conversation is a solved problem in the technical sense (use encryption such as GPG), the only reason that it's not in widespread use is that people can't be bothered.