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[[bold]]4.2 Image Formats[[/bold]]
Each KidSat image is 18MB in its full processed standard TIFF form (3060 x 2036 pixels) and displays an area of 100 to 200 km on a side depending on the lens used to take the photograph. As part of the processing, the image file formats were converted to generic raw pixels and the images were sized down to include one fourth the resolution of the original image.  These images were stretched, based on the maximum and minimum intensity of values of the green band and placed on the Web so that each image could be displayed as the full image, scaled to 720 x 479 pixels (1.011MB), or reduced so that a smaller portion of the image could be seen.  Each zoom step reduced the size of the image by a factor of four. The image or the zoomed region could then be downloaded in a variety of image formats (GIF, JPEG, TIFF, PICT) and sizes (see Table 4).

[[3 columned tabled]]
[[italics]]Table 4: Image Download Options[[/italics]]
|Image Resolution|Pixel Size|Data Download Size (kB)
|Very High|3060 x 2036|1624|
|High|1530 x 1018|406|
|Moderate|765 x 509|101|
|Low|382 x 254|25|

[[bold]]4.3 Data System Interface[[/bold]]
The Data System Web pages allow students to find, view, verify, and analyze the images in multiple ways. Three search options are available fro the Data System page. The Latest Image Search engine presents the images in reverse time order, with the first image page displaying the latest images to arrive at the Data System. This option was most useful during the mission because students viewed the images for the first time as they were downloaded from space to the classrooms. The images are presented in thumbnail format with each image displayed as a 96 x 64 pixel (18kB) image. The Image Viewer function is accessed by clicking on the image of interest. 

The Geographic Search option allows students to search any geographic area of interest by pointing and clicking on a map of the world. There are four types of maps that can be used on a search basis: 
• an image map derived from a global mosaic of optical satellite images from the Advanced Very High Resolution Radiometer (AVHRR) instrument, 
• a political map, 
• a topographic map, and 
• a weather map (also very useful during the mission to determine where to take a picture.)

Available images are shown on the map as colored, diamond-shaped icons with a different color for each KidSat mission. Students zoom in on the map or view a particular image by selecting the Inspect Images icon.

The last method for finding a particular image or set of images is the Form Search, which allows students to find an image by MET, by an attribute of the image, or by viewing a list of image names or thumbnails. Links at the top of this page provide helpful hints and a short tutorial on how to effectively use the Form Search. Searches by geographical content (e.g., images with rivers) are based only on the student validations-i.e., the students are responsible for providing the Data System with the image content. 

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