Tool for Marine Biologist

Sunday, January 15th, 2012

My brother-in-law is a marine biologist and he often will do ocean surveys as a contractor. Recently, he did a survey to measure the amount of eel grass in a certain area. The way that he does this is via scuba and a GPS unit. He essentially gathers data, in a methodical way (I’ll spare you the details), and then uses the data to generate a black & white pixel map. Black areas indicate that eel grass is present. He then usually brings this map into a really expensive software to calculate the total area of eel grass.

I recently happened to be tooling around in Processing and decided to make a very quick and dirty tool to do this calculation. You run this program, pick the image, set the pixel measurement for your area unit, and the software will tell you how many area units you image contains. The interface is not pretty…just functional.

PrimeSense 3D sensor

Thursday, January 5th, 2012

PrimeSense has partnered with ASUS an entered the market with their own 3D sensor, the Xtion Pro Live (There’s actually the Xtion Pro model which doesn’t have a RGB camera…so if you’re just interested in getting 3D data but not actual image data, this is the version for you).

I can’t get one of these yet…just got the Kinect to play with. But here are the comparisons.

KinectXtion Pro Live



Kinect SpecsXtion Pro Live specs

Moving Time Machine backups to a bigger drive

Thursday, January 5th, 2012

I have a drive with 3 partitions (The Big One, Rachel Time Machine, James Time Machine). I had quite an ordeal trying to moving each TM backup to a new/bigger drive. Initially I tried doing a straight copy from the File Manager…i.e. just dragging the Backups.backupdb directory to the new drive. It worked for Rachel Time Machine (took probably 3 or 4 hours). (I also found out that doing a straight file copy essentially is not efficient because doesn’t preserve the links (logical pointers to files) but essentially duplicates the file that the links are pointing to (see patrix’s comments in the link above). After copying the files over, I pointed Rachel’s laptop to use the her new Time Machine drive and I can see all of the older backups. Great!

Migrating James Time Machine to a new drive was not so smooth. Doing a straight file copy took forever (something like 5 to 6 hours)…I basically let it run over night. In the morning I woke up to find that it didn’t work. Here’s the ordeal described for a Stack Exchange post. As you can see from the post, trying to copy using OSX’s Disk Utility didn’t really work the way I wanted to. It basically cloned my drive so that my NEW drive was just as small as my original (I think it basically created a small partition…but the weird thing is that if you look at the disk in Disk Utility, there is only one partition and it should be 1TB, the size of the new drive…hmmm). Carbon Clone Copy didn’t work either. Finally SuperDuper! did the trick!!!

I have to thank this Neil’s Apple Blog post for mitigating some of the frustration along the way…it was comforting to see someone else with the same issue and that a solution was possible!