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Landsat Data

California Landsat Scenes | Metadata | Data Location | Creating JPEGs | Scenes Outside CA

 

California Landsat Scenes

 

The Branner Earth Sciences Library has Landsat-7 Thematic Mapper images for the entire state of California. Most of the scenes were taken during the winter of 1999/2000 and have close to 0% cloud cover.   Each scene is a collection of about 300MB of data.

The individual Landsat CDs also contain a "README.GTF" file (which can be opened with any text editor) that has metadata including a description of the Landsat naming convention.

For more information about the Landsat-7 Mission and its products vists the USGS Landsat-7 Homepage.

To view thumbnails of the images, go to: http://www.sdc.ucsb.edu/imagery_examples/L7/L7.html

For help selecting the scene you want, reference the grid below (click on the image to view a larger version)
 

 


Metadata
 


Lansdat-7 ETM+ Band Characteristics

Band
Number
Spectral Range
(µ)
Ground Resolution
(m)
Data Lines
Per Scan
Data Line
Length (bytes)
Bits Per
Sample
1 .450 to .515 30 16 6,600 8
2 .525 to .605 30 16 6,600 8
3 .630 to .690 30 16 6,600 8
4 .775 to .900 30 16 6,600 8
5 1.550 to 1.750 30 16 6,600 8
6* 10.40 to 12.50 60 8 3,300 8
7 2.090 to 2.35 30 16 6,600 8
8 .520 to .900 15 32 13,200 8

*Values apply to both high- and low-gain data.

Data Location

Most of the state is available on CD-ROM at Branner library. They are held at the circulation desk under the call number G4361.A4 2000.E7. Please specify the path and row number you need. 

The remainder of the state is available via FTP from UC Santa Barbara. Contact the GIS Staff to order any of the remaining California images.

These images are available to Stanford affiliates only.  Please don't send e-mail requests if you don't meet this requirement. 

 

Creating JPEGs

How to create a "real color" JPEG from Landast TM spectral data using ArcView Image Analysis or Adobe Photoshop

Arcview | Adobe Photoshop


Using ArcView Image Analysis

  1. Copy the necessary files from the CD onto the hard drive.  For real color images, you need bands 1,2, and 3.  The band numbers are all the way at the end of a very long file name, so you may have to scroll out. Look for “_b10” etc.

  2. Once you have copied them over, right-click on each file and choose “Properties” from the drop-down list that comes up.  At the bottom of this menu, uncheck the “Read only” box.

  3. Open ArcView.  Turn on the Image Analysis and TIFF extensions.

  4. Open a new view.  Under the View menu choose “Add themes” in order to bring in each of the three bands. Change the Data Source Types” to “Image Analysis Data.” This is important you won’t be able to manipulate the files if you bring them in as anything else.

  5. When asked, do NOT create pyramid layers for the images.

  6. In the Image Analysis menu select Stack Images (You need lots of free disk space in order to perform this operation, and it takes a few minutes).

  7. Once the stack operation is done, a new theme will appear.  Turn it on.  It should look approximately like the real world.

  8. At this point, you have a couple of options depending on what kind of resolution you want.  If you just want a low resolution image, you can now immediately export the image as a JPEG under the  file menu.  If you want a nice,  large, high resolution image, you have one more step.  Choose Theme>Save Image As and change the file type to TIFF.  This will take a long time and create an   enormous image.  If you want a high resolution JPEG then open  this large file in Adobe Photoshop and re-save it as a JPEG.  This will also take a few minutes.  Now you should have an image that   you can work with in any graphics program.

Using Adobe Photoshop (on a PC)

  1. Open the image files for bands 1,2, and 3.

  2. Make one of the images active

  3. From the Window menu choose "Show Channels"

  4. In the window that appers, right click on the black triangle at the top left corner. (This will reveal a secondary menu). Select "Merge Channels."

  5. In the Merge Channels window, select RGB color for Mode. The number of Channels should be 3. Hit the OK button.

  6. In the Merge RGB Channels window, use the pull-down menus to specify band 3 for Red, band 2 for Green, and band 1 for Blue. Hit the OK button.

  7. The resultant image can now be saved as a .jpeg or in a number of other file formats.

 

Scenes Outside California

Several websites provide access to Landsat imagery from around the world. Global Land Cover Facility is the one we use most often. Several other sites are linked from our web data page.

USGS offers a Global Visualization Viewer where you can browse images from several different satellite sensors(ASTER, EO-1, Landsat 1-7, MODIS).

 



Last modified: July 21, 2006

   
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