The first part of Module three, data and tools, presents some of the resources available on the internet to get images from the satellites presented

Transcription

1 The first part of Module three, data and tools, presents some of the resources available on the internet to get images from the satellites presented in the previous module and some uses of the images, including some tools to process these images. This set of slides presents how CBERS images can be downloaded from the Images Catalog of INPE. The other presentations show how to obtain images from other major remote sensing data sets. Specifically, you will learn how to access the web sites, and learn how to locate and download imagery. 1

2 INPE s Image catalog is accessed through the web site shown in this slide. The available images are not restricted to CBERS imagery and contains images from Landsat, India s Resource-sat, MODIS, and also the compilation created by NASA, the Global Land Survey using Landsat images. 2

3 CBERS 2 and 2B images are from CCD, IRM, WFI and HRC sensors. Most of the available images are over South America from the ground station located in Brazil. Some images are available for Africa and they can be browsed by countries. The search capabilities will be shown later in this presentation. 3

4 To Access the catalog, just type in the URL in the address field of your browser. The web page presented in this slide should appear. It is initially shown in Portuguese. We will see how to to change the language in the next slide. 4

5 Change to your preferred language using the options at the upper left corner, as indicated by the red arrow: Português, English, Français or Español. In this presentation we will use English. 5

6 The initial screen shows quick information on how to proceed. The items 1, 3 and 4 are the usual ones to download images. It s better to go to the step 2 first to register as a new user if you really want to download some images. Item 5 is required only if you want to access general information about images, but most of the information is in Portuguese. The software that can be downloaded in item 6 is a very basic one to display images. For any processing, it is better to use a tool such as SPRING, which will be described later in the course. So let s start with the step REGISTER in User s database. 6

7 Click on REGISTER to open the registration page. 7

8 Fill in REGISTER fields. It is important to remember the User name, the second field, and to use a valid address. The will be the only way the system will inform that selected images are available for download or to retrieve a lost password. The other fields will help INPE to understand the needs of different users. Once all fields are completed, click on Register button to register the user in User s database. 8

9 Just click on OK to continue. 9

10 Now you need to log in the system, just click on Log In to continue. 10

11 Type your username and password. If you don t remember one of them or both, click on the text and a new window will be shown, where you can type your . Your username and password will be sent to your address. 11

12 Now the image catalog knows who you are. In the next step, you should specify the parameters to select the images that you want to request. The parameters are defined using the options on the panel located on the left side. To get help on the parameters, you can click on criteria, as shown by the red arrow. 12

13 Parameters options are: which satellite; instrument (also known as sensor); image capture time interval, which can also be a seasonal interval; maximum cloud cover in each quadrant; and location. 13

14 Start selecting the parameters. In this example, let s select a CBERS 2B satellite, HRC instrument, and default values for time interval and cloud cover. To define the location, you can use country, with all countries in South America and Africa, state only Brazilian ones, and city all Brazilian and some important ones in South America and Africa. Type in sao jose in the City field and click on the Execute button just under the City field. 14

15 Scroll the list down and select São José dos Campos(SP)-(Brasil) by clicking on the name. 15

16 Now a map using a satellite image is shown with the location of the selected city indicated by a dark blue arrow. The light blue stars indicate the location of the center of the images from CBERS 2B HRC instrument, which were found in the catalog for the region around the selected city. Pan and zoom controls on the map are available through the icons on the edges of the map frame. The geographic coordinates of the corners and of the current mouse position are also shown 16

17 Click on one of the stars to select an image. 17

18 After clicking on one of the stars, the images that satisfy the parameters are shown using thumbnails. If there are more than 20 images, then multiple pages are available. Select page 2. 18

19 In page 2, click on one of the images. In this slide, the image from July/2008 was selected based on the region and the visual quality. 19

20 The left side shows the image metadata and in the main panel, a larger image is shown. The image is not in full resolution. To obtain the full resolution image, the image must be added to cart. Add to Cart by clicking on the indicated button. After adding to cart, other images can be selected. In our example, we will select this image only. 20

21 The cart must have one image now. Click on Cart to access and finish the image order. 21

22 The window now shows the cart contents, with one image. Note that the media format is FTP, meaning that the Image Catalog system will give you a ftp site to download from. The other option is to receive the image by regular mail, which costs fifty reais. But I have never used this option and do not know how it works to send outside Brazil. Click on Go ahead button to continue. 22

23 The next window is another confirmation one, just to make sure you know what you are doing. 23

24 The request number is shown in the next window. You can continue to browse the catalog or to logoff from the system. 24

25 An acceptance is sent right after the image is ordered. 25

26 Some of the ordered images need processing. The time needed to complete the order depends on that. Usually, in less than a minute, the order is completed and another is sent. The FTP link is shown in the text. Click on it to access the image files. 26

27 The FTP site contents is shown in the web page. The image is available in compressed format using ZIP. Click on the ZIP file image to download the compressed image. The web browser usually asks where the image file should be saved. Choose one folder in your computer and click on the save button. 27

28 Clicking on the compressed file should bring a decompress utility. In this slide, a new folder is created and the zip file contents is placed there. The contents of the image order file are one TIFF image and a XML text. The XML is shown in the slide and it contains information about the image acquisition and processing. 28

29 Other metadata are available as text files in the scenario folder of the FTP order site. 29

30 The TIFF image file can be used in any image processing, remote sensing or GIS software. 30

31 Next, let s look some application of CBERS images. These images were selected by Paulo Martini at INPE. 31

32 This is an image CBERS Wide Field Imager sensor. WFI sensor has 2 bands in red and infrared. This image color composition is infrared displayed in Red and Green color and red band displayed in Blue. The bluish gray areas are being affected by a severe drought in this image from February

33 This is another CBERS WFI image over the ocean. The color composition is infrared band in Red color and red band in green and blue. A careful observation of the image showed a pattern similar to oil spill, since this is the main oil field in Brazil. 33

34 A closer examination of the probable spill was done using CBERS CCD image. The color composition is infrared band in red, blue band in green and green band in blue color. A field survey later concluded that the image shows a natural exudation and not a oil spill. 34

35 This WFI image is over forest and agricultural lands in the south of Amazon basin. The color composition is red band in red and blue color and infrared band in green. The image green shows where there is forest. The dark green areas are wetter forests. Areas in pink are agricultural lands. The dark violet areas are swamps. 35

36 The same region shown in CCD sensor image. The details of each agricultural land can be seen here. Color vectors indicate planning that was drawn on top of the image. Color composition is infrared band in green, red band in red and green band in blue color. Areas where the color in not green indicate different types of land use. 36

37 This CCD image shows pollutant dispersion around Santa Catarina island. The south portion of the bay is exposed to currents from the south and are cleaner than the north side, which is protected from the currents. Color composition is infrared band in red color, red band in green and green band in blue color. 37

38 This is a HRC sensor image. The high spatial resolution of the image allows the features of the largest copper mine in the world, located in Chile, to be appreciated. 38

39 Another HRC image showing an oil terminal. The circular objects are storage tanks. 39

40 To conclude this part, I will just remind that the INPE s image catalog can be accessed using the web page address presented in this slide. Any questions can be asked by or on the schedule chat session. Also, the activity related to this part is in teleduc. In the activity, you should select and download one CBERS image. Good Luck! 40