MrSID - NASA's ESAD (really detailed maps)

kojikun · Post by **kojikun** » 2003-07-16 04:20pm

MrSID Helps You See the Earth From Space

Get an alien's-eye view of your neighborhood.
Watch today at 8 a.m. and 12 p.m. Eastern.

By Patrick Norton

I like to roam around Baja Mexico chasing race trucks, searching for empty surf breaks, and sucking down vast numbers of fish tacos. The downside o' this hobby is the simple fact that very few maps of Baja, North or South, are very good.

While it's not that hard to find your way home -- there's only one road that runs the length of the Baja peninsula -- finding that road before you run out of gas can be a problem.

So I started searching online for satellite imagery of Baja. Sure, it's not a map, but it is a picture of the place, right? Also, the tech exists to link these pictures to GPS mapping software. If I can make it work, I have the ultimate "You Are Here" tool to stow in my truck.

My search turned up something really cool: the most amazing space pics of the Earth's surface I've seen since I showed you the NASA maps a few months ago.

Better than JPEG

The pix come from NASA's Earth Science Applications Directorate. They look so good 'cause they're compressed using the Multi-Resolution Seamless Image Database (MrSID). Designed for distributing imagery over networks, MrSid (LizardTech sells it under the name GeoExpress) uses lossless compression and merges multiple files into an easy-to-browse mosaic.

Why should you care? Unlike, say, a JPEG file, as you click on the "zoom in" microscope, these files still look sharp. They don't become giant blocks of pixels. They look gorgeous.

Here's how you get 'em

Download a SID viewer from LizardTech Software's download page. Unless, of course, you just happen to have some serious GIS software lying around.

Open this page on NASA's Earth Science Applications Directorate website. You'll probably need to use IE to get it to work. My install of Mozilla wouldn't work on the next step.

Select one of the tiny blue squares over some portion of the Earth you want to see.

See the square for the area you want? Good. Check the "Select Image" button and click the square you want. The image should launch in a new browser window.

If you want to download the image to your hard drive, spiffy. Just click the "Download MrSID Image" link. Be forewarned: The ones I've downloaded range from 29MB to more than 40MB!

Happy viewing!

Learn more about the images

The ESAD put together a great tutorial. It has tips on how to read the images and explains how color has been pumped up from true color (vegetation is green, urban areas are lavender, water is black to dark blue, bare soil is magenta, lavender, or pale pink).

Tell your congressional rep and senators to show NASA some love when they're working on the federal budget!

More SID images

NIMA's historical maps, from Lewis and Clark through D-Day
Clementine Lunar Image Browser

kojikun · Post by **kojikun** » 2003-07-16 10:50pm

^^Bump^^

cmon, surely someone thinks this is nifty.

Mitth`raw`nuruodo · Post by **Mitth`raw`nuruodo** » 2003-07-16 10:54pm

kojikun wrote:^^Bump^^

cmon, surely someone thinks this is nifty.

I'm sure it's great, what areas can you get pictures of?

kojikun · Post by **kojikun** » 2003-07-16 11:10pm

Mitth-raw-nuruodo wrote:
kojikun wrote:^^Bump^^

cmon, surely someone thinks this is nifty.
I'm sure it's great, what areas can you get pictures of?

Why don't you take a look at the website and find out.. or because youre lazy, The entirety of the planet (except tiny islands and stuff in the pacific).

Xenophobe3691 · Post by **Xenophobe3691** » 2003-07-16 11:31pm

Wow....I can see my house? Is it like Terraserver, or is it better?

Warspite · Post by **Warspite** » 2003-07-17 06:09am

I'll give it a go later... Sounds good.

kojikun · Post by **kojikun** » 2003-07-17 09:48am

Its not literally good enough to see your house, but its pretty close.

phongn · Post by **phongn** » 2003-07-17 11:44am

Terraserver has aerial (as opposed to things like LANDSAT) reconnaisance so you get more detail. However, GIS data from LANDSAT tends to be more accurate (as photocomposites can have problems) and can bring more information.

kojikun · Post by **kojikun** » 2003-07-17 12:04pm

phongn wrote:Terraserver has aerial (as opposed to things like LANDSAT) reconnaisance so you get more detail. However, GIS data from LANDSAT tends to be more accurate (as photocomposites can have problems) and can bring more information.

Ahh but are Terraserver's images *.sid?

phongn · Post by **phongn** » 2003-07-17 12:10pm

Terraserver is not GIS information, unfortunately.

kojikun · Post by **kojikun** » 2003-07-17 12:24pm

phongn wrote:Terraserver is not GIS information, unfortunately.

Well fuck that then.