Read posts about engineering

September 25

CHDK (eccentric squares (Kuya)) by noel

the canon hacker's development kit allows you to upload user developed software upgrades to your canon camera. i tried it on my trusty old SD700IS and it worked great. what initially drew me to CHDK was the auto exposure bracketing, since i was looking into some of that computational photography stuff. here's a list of features from their FAQ:

  • Shutter-priority (Tv) exposure - via shutter value override feature
  • Aperture-priority (Av) exposure - via aperture value override feature
  • Shooting in RAW, with RAW Average, RAW Sum, and RAW Develop features
  • Live histogram (RGB, blended, luminance and for each RGB channel)
  • Zebra mode (a live view of over and under-exposed areas of your picture)
  • Depth-of-field (DOF)-calculator, Hyperfocal-calculator with instant Hyperfocal and Infinity focus-set, and more
  • Battery indicator
  • RAW and Video space-remaining gauges with custom low-limit alerts
  • USB cable remote shutter release
  • Motion-detection trigger - automatically fires camera on motion detection. (Fast enough to capture lightning strikes.)
  • Customizable high-speed continuous (burst) Shutter-based (Tv), aperture-based (Av) and ISO-based exposure bracketing (unlimited shots)
  • Focus bracketing (unlimited shots)
  • 99 constant bit-rate and 10 constant-quality video compression levels
  • Elimination of 1 Gig video-size limit
  • Zoom during video function (for cameras without this feature)
  • Shutter, Aperture, and ISO Overrides
  • Ultra-long shutter speeds - up to 64 seconds
  • Ultra-fast shutter speeds - up to 1/10,000" and higher
  • High-speed Flash Sync at all speeds up to 1/64,000 second (even faster in some cameras)
  • Custom user-editable visible Grids for framing, cropping, and alignment
  • File browser
  • Text reader
  • Calendar
  • Some fun tools and games :)
  • Fully customizable CHDK display, info placement, user-colors, fonts in menus, etc.
  • Custom CHDK User-Menu (for instant recall of up to 10 favorite functions)
  • Scripts execution - including exposure bracketing, focus bracketing, intervalometer and more)
  • And other features too numerous to mention here. See the CHDK Firmware and Allbest Firmware usage pages for a more complete overview.
and a list of supported cameras:

if you have one of the listed cameras and are looking for any of the above features (or are really just looking for a painless way of getting your money's worth out of your camera), i'd say check out CHDK.

Posted in: cs , engineering , math
August 15

computational photography (eccentric squares (Kuya)) by noel

i'd gotten interested in computational photography at my last job, where i applied some HDR algorithms to satellite data. at SIGGRAPH, they offered several talks/papers on the topic as well as a great class (esp the sections given by jack tumblin) which reviewed the recent academic literature (there's been a lot) from the past 2 years.

at this point, the relevant question would be: what is computational photography? according to their website:
Computational photography combines plentiful computing, digital sensors, modern optics, actuators, and smart lights to escape the limitations of traditional film cameras and enables novel imaging applications. Unbounded dynamic range, variable focus, resolution, and depth of field, hints about shape, reflectance, and lighting, and new interactive forms of photos that are partly snapshots and partly videos are just some of the new applications found in Computational Photography.

an excess of text in a post about imagery is pretty lame, so in this post, i'll just describe (at a super high level) and link to some cool applications in this area.


the area that i had initially gotten interested in and which is becoming much more mainstream now is HDR imagery. high dynamic range images are ones which have scenes with super bright areas and super dark areas. to capture HDR images, ordinary cameras will capture several exposures of the exact same scene. post processing will combine the exposures into a single image which effectively conveys those high dynamic ranges on our low dynamic range monitors. tweaking the parameters to these algorithms can give photographers artistic license, yielding sometimes surreal looking photos:


programs like photoshop currently support HDR file formats and tone mapping and certain cameras offer features like auto bracketing, which can help in acquiring the exposures used as inputs into HDR tone mapping.



another easily accessible area is in panorama/auto stitching. these have been out for a while now, i got a program to do this with my canon SD700 2 years ago and photoshop CS3 has this in there too. this is a complex problem however, as if you've tried stitching together >100 gigapixels worth of images together, you'll find out what your computer isn't so happy. a recent SIGGRAPH talk demonstrated an algorithm which took an hour crunch on a notebook on a problem which took my work computer several days (before crashing and burning).



a couple areas were targeted towards removing blur from photos. a couple years ago, mitubishi announced it would develop a camera which would facilitate motion deblurring. the image linked above and this paper (both show some pretty amazing results) are software techniques to remove blur. this paper (image below) even gives an algorithm for removing haze:


with sites like flickr, the widespread availablity of geolocated images is now a reality. one pretty freaky project builds up a statistical analysis of the outdoor lighting conditions in these large data sets so that, given a time stamp, the system can identify the location to within 50 miles!



if you've ever had to crop or resize an image, watch the video above. they have a method to interactively size images and movies without distorting proportions. ...just watch it.



a super cool demo related to the problems i work on now is microsoft's photo tourism/photosynth. it effectively recreates 3d spaces from 2d photos, allowing the user to take virtual tours.



above is another cool demo out of microsoft research called unwrap mosaics. the intermediate stage (the unwrapped mosaic) is frightfully reminiscent of a picasso painting, but the end product and apparent ease with which its produced is almost comically easy.
Posted in: cs , engineering , math , pictures , video
April 28

i like to move it move it, ya like to MOVE IT! (eccentric squares (Kuya)) by noel

i switched careers recently, from the aerospace industry to the entertainment industry. i'm working at a motion capture company, and to get us up to speed on the system, we spent the day as talent (aka actors). here are some pics from that day (keep in mind that we're actually getting paid for this hahaha).

Posted in: cs , engineering , math , pictures
March 7

you are here (eccentric squares (Kuya)) by noel




i've told people before that i spend a large amount of time at work, just staring at the clouds, here's an example of what i really mean. in testing some of my code, i randomly pulled this data for unit testing purposes and it was so pretty, i decided to make it my desktop wallpaper. i put this composite together with that code along with some manual editing in photoshop.

originally i wanted to take the original and make posters of it, but it got watered down significantly in the process for making it fit for public consumption. i've literally spent hours just zooming into and admiring the expected and unexpected features in the unaltered images. it's pretty cool to make animations out of these too. anyway, i think this version still looks pretty amazing (especially if you haven't seen the earth in infrared before) and it's probably also the most expensive desktop wallpaper evar lol.
Posted in: cs , engineering , math , pictures

they are there (eccentric squares (Kuya)) by noel

another public release image below, sanitized for the unwashed masses. you'll notice that this one is just black and white. well, that's because i had massively photochopped the other one lol. in that picture, i had just taken the intensity values per pixel and multiplied by the blue from the NASA visible light Blue Marble photos. this one is slightly truer to it's native form, where the brightness of each pixel is some funny function (my aesthetic preference) of irradiance.


Posted in: cs , engineering , math
February 24

Das Boot (Kilala.nl (Cailin Coilleach)) by Cailin Coilleach

Not many people know this, but if it weren't for my bad eye sight I would not have gone into IT. I'm not even sure if I ever told Marlijne, because this was way before her time. Right after leaving high school I looked into one option that I have left eschewed.

You see, I would have pursued a maritime career as first officer or as shipboard engineer if I had the chance. I have no logical explanation for this, but I feel some odd, deep draw to the sea. It's not like I've lived anywhere near the sea, or that I've been involved with Her in any way, but still that feeling exists deep down in me. Heck, I might not even be that suited for a life at sea!

And the engineering role brings me to another thing that has a strange draw to me, one that I've also left completely ignored: heavy machinery. I love the scent of diesel and oil and find lure of huge engines enticing. I think I would greatly enjoy a line of work that will allow me to maintain beasts like those.

But *sigh* For now those are two career tracks that I'd better leave alone. The first would take me away from home more than I would like, while the other would require such strenuous re-schooling that it is currently unfeasible.

What brought all of this on? Ah! I just sat through the director's cut of Das Boot, on ARD-1.

I leave you tonight with a wonderful quote from the movie (some background to the quote).

Aber wir wussten auch dies:
Einmal vor Unerbittlichem stehen,
wo Gebete entrechtet, Gewinsel zu Gott lächerlich ist,
wo keines Mutter sich nach uns umsieht, kein Weib unsern Weg kreuzt,
wo alles ohne Liebe ist, wo nur die Wirklichkeit herrscht, grausig und groß,
solches macht sicher und stolz.


Posted in: career options , das boot , engineering , the sea