Antti Kupila

Personal Blog, Portfolio and Online playground

View over the green room at Sid Lee, Montreal

Pixel Bender levels example

Pixel Bender is huge and is going to be even bigger once Flash player 10 officially is out (and spreads a bit so that we can start using it in commercial projects). I just love it when Adobe constantly lower the restrictions on creativity :)

A lot of the examples we see online for Pixel Bender (previously codenamed Hydra) are crazy visual effects. While they’re amazing for certain visual effects (mostly due to the processing speed), finding real life use is harder. I’ve had the need for a similar-to-photoshop levels filter multiple times, if nothing else for preprocessing a bitmap for further analysis. Turns out creating something like this with Pixel Bender is really simple and even better; it’s blazing fast.

If you’ve read my previous articles you know that I’ve already written a prototype for the levels filter (geesh, it’s almost a year ago!). Well, back then Pixel Bender was called Hydra and the code written isn’t compatible with today’s version anymore. I addition to that we weren’t able to export stuff, it just ran in the Hydra toolkit. Today I updated the code and exported it as a .pbj that can be used in Flash.

I’ve made a small example with a couple example images with the contrast reduced. You’ll need Flash player 10 to play with it. If all you see is white download the plugin from Adobe labs.

A couple pointers on the example: Clicking a histogram will automatically balance it. Double clicking will reset it to 0-255. Clicking the image will load a new image. In photoshop you can choose to either modify the luminosity or the individual channels. Here i enabled you to modify both at the same time, but this means that if you modify all 4, the automatic mapping won't be correct anymore (the histogram in the bottom left corner will show the result of this). I could make it understand this, but since it's just a proof of concept i think this is fine. Also gamma isn't supported at the moment.

The source is of course available:

Do you have other real life uses for Pixel Bender?

Stack Overflow goes live

The name Joel Spolsky may or may not ring a bell in your head. If not, maybe Jeff Atwood or the site Well, these guys have got together and built a resource for programmers. The goal of the project is simply to “”. The site launched for the general public today.

I’ve been following the project with the weekly podcasts since they started them . It’s been interesting to listen to the progress of a site like this which essentially is doing the same thing as many other sites out there, but trying to do it better. If they succeeded or not is for you to decide but judging from the beta I’ve been testing recently, i think it’s definitely looking good.

I think an interesting approach has been the balance between technology and psychology in the project. A social site of course has it’s technical challanges with databases and such but even more it’s the human side to it. Sure you can optimize your code, squeeze out every millisecond, add a bunch of features and all that but if it’s not usable to a human being or even more precisely the target group, it’s not going to work. If you ask me it’s the non-technological features that make stackoverflow rise above the rest; the site encourages users to make it better.

Take it for a spin:

Also read Joel’s post: Stack Overflow Launches
Jeff doesn’t have one up yet, but I’m guessing he’s going to write something so keep your eyes peeled.

I’m sure the site will change & improve a lot in the coming year so make sure you come with your ideas to the team.