MrSID - NASA's ESAD (really detailed maps)
Posted: 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
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
