I fell like this should be known to everyone by now, but every once in a while I see an otherwise clever person looking at internet ads! I hate to tell you guys… that’s sooooo 2005.
In fact, I haven’t seen an internet ad in years. Who do I thank? Adblock Plus. This is a Firefox plugin, so if you’re using Firefox (which you should be)… you can be ad-free just moments after clicking here (to get Adblock) and then here (to get the set of filters).
In this project I look at engineering from a different perspective… the business perspective. My team and I started with an idea: Track cars in a parking lot and use the information to help the whole operation run smoother. From there, we researched, though, and schemed until we had a sturdy business plan for the new venture. Click to continue →
If you do computer vision research (as some of you may). Or any other type of research for that matter… Its a good idea to make nice videos of the results that you obtain. This is a simple disaster-proof way of demoing your work. I’ve been doing this quite a bit lately (as a result of all the video tracking work). I’ve come up with some tips, tricks, and tools that will help out the aspiring video-creator (who uses Matlab and Linux… otherwise you’re out of luck).
Personally, I find Matlab’s built-in avi code terrible. It’s just bad. Instead, I prefer to make figures that show what I want to show on each frame, save those out, and then compile them into a movie later. This seems to be the nicest command to save the frames out:
>>for i=1:last_frame
>> %% code to create the frame in a figure
>> f = getframe;
>> imwrite(f.cdata, sprintf('./video/%04d.png',i));
>>end
This should leave you with a directory full of .png files. From here you have to assemble these into a movie. This is a fantastic script called mkmpeg4 (download). The way to run it is as such (by the way, this only works in Linux with mplayer installed)
$mkmpeg4 -o output.avi -f 30 `ls *.png`
$mplayer output.avi
Note the ` quotation marks as opposed to your typical ‘ marks. This makes compressed videos that look good and will still play on Linux, Windows, and Mac. (Also, they work in PowerPoint). One final tip. If you want to go the other way; take a video and convert it to frames, here’s how:
$mplayer -vo png movie_to_unpack.avi
If you video file is interlaced (looks good in a player, extracted images look bad), try this instead:
$mplayer -nosound -vf pp=ci -vo png:z=0 movie_to_unpack.avi
Happy Matlab Video-ing. Feel free to post your own tips or correct mine in the comments.
Eurotrip 2007 is officially on. I purchased some tickets so now its happening! I’ll be flying into Paris on May 7th and flying back to the US from Munich on the 21st. In the meantime, I hope to pass through Italy and Switzerland. I would very much like to meet up with anyone who will be anywhere close. Here is my plan so far:
… as you can see, its not too detailed. I’ll be getting some details done in the coming weeks… I’m pretty excited about this trip. Any suggestions, invitations, ideas, warnings are welcome. See y’all in the EU.
My newest research focus has moved away from medical images and towards moving images… And instead of finding organs and tumors, I’m tracking moving objects in the videos. Check out some of my latest successes (and failures). Click to continue →
This weekend, my buddies Ryan, Ian, and I went for a bonanza hiking/camping trip on the Georgia/Tennessee Border. Over the course of 24 hours we:
- Hiked 20+ miles
- Crossed a river about 22 times
- Jumped off of a 25 foot rock overhang into a waterfall
- Climbed a mountain
- Camped out
- Got wet and rained on
- Saw about 10 people total
- Finally made it back
It was a great trip. As an exercise in ‘minimalist camping’ we took only 1 tarp and a blanket to sleep on. While it made the packs lighter for the hike, it certainly made it a wet night when it started raining and blowing fierce wind at the top of the ridge where we were camping!
Check out some of the pictures:
The tree of us on a rock.
Me in front of Jack’s River Falls.
Yikes! 25 Foot jump!
Mmmmm. Hot soup after a long day.
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