Thursday, August 23, 2007

The Power of GIS


I read Lou Minatti's blog every day, and he posted a photo over there that I've seen before. It appears to be a newspaper photo from the Roanoke Times of a smoking woman standing in her front yard pondering what the sound of jackhammers will do to her unborn child. (Get it? Smoking. Pregnant. Sound of jackhammers is worse.) I agree with Lou that the caption could have been Photoshopped.

I don't think it's a faked photo though. In fact using the truly awsome power of GIS here at the Virginia DOT, I've even tracked down the exact location the photo was taken. Take a look at Lou's original blog entry. Compare that to my photo. (Click to make the photo bigger.) The hydrant. The house of the left side of the street. The Hardees down the block.

The woman was standing right behind the stone wall of the house on the corner on the right. Corner of Bullitt Ave & 8th St E, Roanoke, VA. Latitude 37.267867N, Longitude 79.93010W.

2 comments:

Lou Minatti said...

Howdja do that???

Michael Ryan said...

How? It wasn't too hard. All the clues were there.

An article in the Roanoke Times speaks as if every one knows where Bullitt Ave. is, so it must be in town.

Bring up my copy of ArcGIS, load the data layers for road centerlines (which I've spent thousands of hours on helping build), Tiger Roads 2000 (for Postal Service street names), and aerial photos (which I've helped load and vet).

Query for Bullitt Ave, and then bring up our "right of way" images. These were collected by a van driving the street taking a photo ever 1/100 mile. (I "touched" every one of 5.5M images, back in 2002, as I loaded them from tape.) "Drive" the street, and Bingo!

We even have a public version of the ROW image viewer. (Works in IE only.)
- Go to http://198.176.41.132/
- Choose Roanoke from the Jurisdiction drop-down (Be patient while it looks up the available routes.)
- Choose "PR 24" from the list (Yes, that's what I needed the road centerlines for.)
- Choose to start the virtual drive at intersection 50.
- Click the "Drive It!" link
- A "VCR-like" player will open where you can single step or 'drive' the images. The image I showed was 8 (0.08mi) from this starting point.