Landsat 8 Pansharpen and Mosaic Geomatica 2015 Tutorial

Transcription

1 Landsat 8 Pansharpen and Mosaic Geomatica 2015 Tutorial On February 11, 2013, Landsat 8 was launched adding to the constellation of Earth imaging satellites. It is the seventh satellite to reach orbit successfully but the eighth satellite in the Landsat program. Landsat 8 operates in the visible, near-infrared, short wave infrared and thermal infrared spectrums. It captures an average of 400 scenes a day ranging from Earth s land surfaces to its polar regions. Landsat 8 data is freely available for download. Landsat 8 data can be acquired a number of different ways through the USGS website Google Earth, Earth Explorer or Glovis are all tools available to download imagery. Please refer to our tutorial on acquiring Landsat 8 data for more information on downloading imagery. This tutorial shows the steps required to pansharpen and mosaic a number of Landsat 8 images. Initial Project Setup 1. Open Focus from the Geomatica 2015 toolbar. 2. To view the extracted images in Focus drag and drop the _MTL.txt into the Focus window. Select MS to load the multispectral channels. Click OK. 3. Drag and drop the _MTL.txt into the Focus window a second time. Select PAN to select the Panchromatic channels. Click OK. Page 1

2 4. Repeat this step to load all images into the Focus viewer. Pansharpen Creating a pansharpened image by combining the multispectral data (30m resolution) and panchromatic data (15m resolution) will result in a high resolution 15m color image. 1. Open the Algorithm Librarian from the Tools menu. 2. Navigate to the PANSHARP algorithm. Page 2

3 3. Select multispectral channels for the Input Multispectral Image Channels. 4. Select panchromatic channel 8 for the Panchromatic Image Channel 5. Select an output file name and location. 6. Click Run 7. Run the PANSHARP algorithm on all images in your dataset. Page 3

4 Mosaic Creating a mosaic of the images will allow for a seamless image. This is done through OrthoEngine. 1. Open the Geomatica 2015 OrthoEngine application. 2. In OrthoEngine click File New. 3. Give your project a Filename, Name and Description. 4. Select None (mosaic only) under Math Modeling Method. 5. Click OK. 6. Click Cancel on the set projection window. Click OK on the window that tells you that the projection information will be read in from the imagery. 7. Select Data Input as the Processing step. a. Click Open a new or existing image b. Click New Image. c. Navigate to the location of the data. Select all the pansharped images and click OK d. Click Yes when asked if you wish to create overviews now. Page 4

5 8. Select Mosaic as the Processing step. Click Define mosaic area. 9. In the Define Mosaic window select a file name and location for the output mosaic file. Click OK 10. Select Automatic mosaicking from the OrthoEngine Toolbar Page 5

6 11. The default parameters can be used in the Automatic Mosaicking window or changes can be made to the color balance, cutlines or blend width. a. Click Generate Mosaic when ready to do so. This may take a while. b. Click OK when the mosaicking process has completed. c. Save and close the OrthoEngine Project. Page 6

7 You can now open the mosaic file in Focus. Page 7