Geomatica Focus Version 10

This section primarily deals with how to accomplish certain tasks in Focus. Some of the questions may also deal alternative solutions to perform tasks in Modeler or EASI/PACE.

Geomatica Focus is a visual environment for working with a variety of data, including imagery, vectors, and graphical bitmaps. It is an application for viewing, enhancing, and examining remotely sensed imagery such as LANDSAT, SPOT, RADARSAT, ERS-1, NOAA AVHRR, Ikonos, and aerial photography. It also enables users to overlay their GIS data and view the attribute information included with such data. Focus includes many useful display tools, such as fast roam and zoom, image enhancements, numeric values display, and attributes table display.

The DN values reported in the ATCOR2_T result do not look to be in degrees Celsius. How can I convert the ATCOR2_T result to temperature in degrees Celsius?

What is the Algorithm Librarian in Focus?

I have an image channel and a pseudocolor segment. How do I display this as a three channel RGB image?

I have image data in Geotiff format but each channel is currently a separate file. How can I combine these into one RGB file?

I have used ASP (from the Algorithm Librarian) to create an aspect image from my DEM. Why are the resultant range of values in my aspect image between 0 and 510 instead of 0 and 360?

How do I get my scale bar to show kilometers instead of meters?

I used the NDVI script from the PCI Script Exchange page but it resulted with a grey-scaleimage, how can I group the valuesPCI Geomatics Support Center: Geomatica Focus FAQs of the image to represent my NDVI results in color

Why does my TIFF image look different in ArcGIS then it does in Focus?

When you add a point symbol or text to an image when the viewer is set to Area View mode, it will remain the same screen size regardless how far you zoom in or out. Why is this?

How can I only use a selection of records for an attribute as labels and not all the records?

I have a vector layer with an associated .rst file.  Is there any way that I can embed the representation so that it is saved with the .pix file and not with the associated .rst file?

I have an EASI script that runs a command that requires user input (i.e. PCIMOD). Each time I run my script it stops at this point. How do I incorporate user input in my EASI script so it will continue to run?

How can I add DEM elevations from a raster to my vector layer as a z coordinate or attribute?

How do I resample my image to a higher or lower resolution

How can I automatically add geometry attributes (length, area and perimeter) to my vector line and polygon layers?

How do I load my classified image and saved PCT?

How can I permanently scale and enhance my 16 bit image in Focus?

How can I export the same image channel from an existing file into a new image in Focus?

How do I add or delete layers to my file in Focus?

How do I create a Bitmap from my polygon vectors?

How can I remove the graticule lines from my grid on my map layout but retain my numeric values in Focus?

How can I export my classification to a Shape File?

How can I make my black "No Data" region transparent so that it does not cover my other data layers?

What does PCIDSK Linking do?

How do I generate a profile cross section of my terrain layer in Focus?

Can I collect GPS data directly into Focus?

What is the overview window and how do I enable it?

How do I enable vector snapping when I am creating new lines?

How do I set up a Digitizing Tablet in Focus?

What types of Meta Data is supported in Focus?

What are Pseudo Color Tables (PCT)?

What are Bitmap Segments?

What are Orbit Segments?

How can I convert my data to a different format to use with other software packages?

How do I import ASCII data in Focus?

How can I open data from a remote data source in Focus?

I use undefined Image data in Focus?

How do I clip files in Focus?

What is the Data Merge Wizard in Focus?

What is the Smart Digitizer tool?

What does Clone View do in Focus?

What are Named Regions?

How to use a math Model with an Image?

Can I create a map that is not rotated north up?

How do you combine several vector layers into one?

Should I always use the PCIDSK format when working in Focus?

How do I change the paper size of my output map?

Q) The DN values reported in the ATCOR2_T result do not look to be in degrees Celsius. How can I convert the ATCOR2_T result to temperature in degrees Celsius?

A) ATCOR2_T calculates a surface temperature for a flat area given a thermal Sensor. The temperature result has a scaling factor of 4.0 applied to it (for 8-bit data and 10.0 for 16-bit data). In order to get real temperature in Celsius, the value must be divided by 4.0.

For example a value of 100.0 will be 100.0/4.0 which gives 25 deg C.

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Q) What is the Algorithm Librarian in Focus?

A) The Algorithm Librarian in Focus is where all of the commands and tools essential to manipulating your data sets are located. The Algorithm Library is crucial to the Geomatica suite and contains predefined and user-defined programs that are organized in a tree structure. You can expand a category in the tree the way you would any other Windows application by clicking on the + next to a folder. When you expand a category or a sub-category, the items inside each folder are arranged in alphabetical order. Some folders contain sub-folders and some contain only a list of algorithms.

Some algorithms may not be available with the Geomatica license you have purchased. Files in the Algorithm Library that have a lock icon to the left of the algorithm name are not available. Contact PCI Geomatics for more information on your license package and for advice on the best Geomatica license for your needs.

The Algorithm Librarian dialog box allows you to search the algorithm directory tree. You can also create your own user-defined category folders to hold the algorithms that you use most often.To open the Algorithm Library, select Algorithm Librarian frrom the Tools menu. You can search through the categories within each folder using the Find utility or you can browse through the categories based on the directory topics found in each folder.

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Q) I have an image channel and a pseudocolor segment. How do I display this as a three channel RGB image?

A) There are two ways to do this in Focus.

• You can use the Add Layer Wizard with the Pseudo Color data type option

or

• You can switch to the Files tab, right click and use the Add option to open your image file, (or if your image is already loaded into Focus, then just switch to the Files tab) then right click on the raster layer and choose View As Pseudo color.

Each case above will load the image data with a default PCT unless you specify otherwise.  To specify your image layer to use a specific PCT layer after you have loaded your image as a Pseudo Color image switch over to the Maps tab and open the PCT Layer Properties window by right clicking on the file and selecting Properties… After the window opens up, switch to the Source Image tab, you can then specify which PCT segment to use with your image (The PCT segment can be located in the same file or you can also use one from another file).

Another option that you may want to use is to create a permanent RGB image from your input image data and your PCT segment so you can avoid loading the data with the PCT layer every time. To do this use the PCE (PCT encoding) program in the Algorithm Librarian to convert the PCT and the image layer to a new RGB image.

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Q) I have image data in Geotiff format but each channel is currently a separate file. How can I combine these into one RGB file?

A) There are several ways to combine three separate to file to one RGB file:

1) In Focus select Tools, Data Merge. This will open the Data Merge Wizard. Walk through the Wizard selecting the image layers you want to combine and the proper geo information for the new output file to create.

2) With Modeler, add an import module for each image layer that you wish to combine on to the canvas and then select one of the images for each Import module. Add a merge module and connect up the import modules. Finally add an export module and set up the output parameters for it. Connect the Merge module to the Export one and then run the Model.

3) You can also use the Transfer Layers tool (from Focus, Modeler or Ortho Engine) to transfer image channels into an existing file. From the Files menu locate the Transfer Layers window. Select the source and destination files and then choose the image layers from the left hand side of the window that you want to transfer, click >Add> and then the Transfer Layers button (continue with the remaining files).

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Q) I have used ASP (from the Algorithm Librarian) to create an aspect image from my DEM.Whyare the resultant range of values in my aspect image between 0 and 510 instead of 0 and 360?

A) The value of 510 is a default value that represents the areas of your image that had no slope, if you look closer at your values you will notice that they should be between 0 and 360 with the exception of the 510 values that are representing zero slope, since no slope would have no orientation.

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Q) How do I get my scale bar to show kilometers instead of meters?

A) To change the scale bar units in the Focus surround from displaying Meter to Km:

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Q) I used the NDVI script from the PCI Script Exchange page butit resulted with a grey-scale image, how can I group the values ofthe image to represent my NDVI results in color?

A) The output from the NDVI image is a grey-scale image because the results are stored within one image channel with values rangingfrom -1 to +1. If you would like to see the NDVI image in color, then you can either use a PCT (pseudo color table) or with the Representation editor in Focus.

A) When your image is viewed in Focus, it will often have an enhancement applied to it that allows it to be optimized for viewing with the human eye, often removing enhancements to your data will result in the image appearing dark and hard to see. When the same file is opened in most software packages such as ArcGIS it will not be optimized and will appear dark. In Focus you can customize your image and then export it with the visual enhancements preserved so that when viewed in ArcGIS it will appear the way that you want it to.

• In Focus set customize your image with the desired enhancement to appear how you wish it to be viewed in ArcGIS.

• Right click on your file name (under the maps tab) and select Save As option.

• In the Save As window, select your output file name, the file format and the bands that you wish to include in your new file.

• Next select the Properties… button for each layer to customize the Output Later Properties.

• In the Scaling Option box choose VISUAL option and select OK (repeat for each layer).

• Click the Save button to create the new file and when you open it in ArcGIS it should appear the way that you want it to be viewed.

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Q) When you add a point symbol or text to an image when the viewer is set to Area View mode, it will remain the same screen size regardless how far you zoom in or out. Why is this?

A) In Map View mode when you zoom in on a point or text it will become larger on screen. You can zoom in to a point where that one symbol fills the whole screen. This is fine in Map View Mode because zooming is equivalent to simply moving the paper closer to your eyes.

In Area View Mode, this behavior is not particularly fitting. When you zoom in Area Mode you presumably would like to capture additional detail about the geographic region you are viewing. So, when you zoom in Area View Mode, text will use the same number of screen pixels.

If you do not like this method (or are having a hard time reading text when zoomed in), then you can change that option by simply, going to View on the main menu and selecting Display Options... to open the Display options window where you can check the "Scale Representation When Zooming in Area View Mode" and then click the OK button.

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Q) How can I only use a selection of records for an attribute as labels and not all the records?

A) Open your file in Focus and then open the Attribute Manager for your vector layer from the Maps tab. In the Attribute Manager use your mouse and the CTR key to select the records you wish to label and then close the window.Right click on the vector layer in the Maps Tree and select Properties to open the Vector Layer Properties window. Switch to the Labels tab and click the Add New… button. Choose the attribute that you wish to label and the other optional parameters such as style and positioning. Click the Apply and the OK buttons to continue and then only the records that were highlighted in the Attribute Manager will be labeled for your vector layer.

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Q: I have a vector layer with an associated .rst file. Is there any way that I can embed the representation so that it is saved with the .pix file and not with the associated .rst file?

A: It is possible to embed the representation for a vector file.In Focus, open your vector file and the RST file. While under the Maps Tab click and drag the RST layer onto the vector layer (the vector layer will be highlighted for an instance to show it is affected). Right click on the Vector Layer and select Properties to open the Vector Layer Properties window. Then under the General Tab, click the Embed button, click the Apply button and then OK. Lastly right click on the vector layer and select Save.

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Q) I have an EASI script that runs a command that requires user input (i.e. PCIMOD). Each time I run my script it stops at this point. How do I incorporate user input in my EASI script so it will continue to run?

A) When using the PCIMOD command in an EASI script, you will get the following error message when you try to run it:

*** WARNING ***

If PCIMOD aborts before completion PCIDSK file may be corrupted! Make a backup copy of PCIDSK file on tape or disk before continuing. NEVER abort PCIMOD using CTRL-C. Always let it run to completion. The PCIDSK file is NOT corrupted if PCIMOD fails due to lack of disk space.

 Do you wish to continue? [Y/N] _

To get past this user input step add the following command to your EASI script before the PCIMOD command is run:

EASI>monitor="OFF"
EASI>run PCIMOD
You should turn it back on after you run PCIMOD to ensure proper error reporting
EASI>monitor="ON"

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Q) How can I add DEM elevations from a raster to my vector layer as a z coordinate or attribute?

A) If you have a vector layer with vertices that have only x and y coordinates, you are able to extract the elevations from a raster DEM for each vertex using the SETELEV command in the Algorithm Librarian. SETELEV will overlay the vector layer on top of the raster DEM and assign a z coordinate to each vertex using bilinear interpolation for the georeferenced coordinates. The new elevation value will overwrite any previous z coordinate, or if none were present, it will add a new one.

Similar commands: VIMAGE or VSAMPLE can be used to extract pixel values and add these values to the attributes. You can extract elevations from a DEM, but these values do not become the z coordinate, they will be added to a new column in the vectors attribute table. The VIMAGE command can be used on point or polygon vector layers and the VSAMPLE can be used with point or line vector layers.

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Q) How do I resample my image to a higher or lower resolution?

A) If your images are georeferenced then you can use the Reprojection function in Focus, Modeler or Ortho Engine.

• In Focus select Reprojection from Tools on the main menu.

• In the Reproject Window select your Source (existing) and Destination (new) files.

• In the Reprojection Bounds section select "use bounds & resolution", then manually enter the pixel size (X and Y) for the desired resolution in to the Pixel Size boxes.

• In the selectable layers section, highlight all the layers of your file and move them to the new file by clicking the >Add> button and then click the Reproject button.

Your new file should contain the same georeferencing information but have a different pixel size.

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Q) How can I automatically add geometry attributes (length, area and perimeter) to my vector line and polygon layers?

A) Geometry attributes are automatically created for all vectors created using Geomatica however it is also possible to add the geometry attributes to vectors which do not contain them. To add geometry attributes to previously digitized lines and polygons:

• Open the file in Focus.

• Open the Attribute Manager for the file.

• From the Field menu, select Add New.

• Click the Create button at the bottom of the Table Definition window.

• Confirm the geometry fields that will be added by clicking OK, then Apply.

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Q) How do I load my classified image and saved PCT?

A) Go to the files tree list (under the File tab) in Focus, expand theraster layer, right click on the classified channel, and select View | As Pseudo color.Switch to theMaps tab then right click on the pseudo colored layer and select Properties to open the PCT Layer Properties window. Here you can specify what PCT to open with this image.

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Q) How can I permanently scale and enhance my 16 bit image in Focus?

A) When your 16 bit image is viewed in Focus, it will often have an enhancement applied to it that allows it to be optimized for viewing with the human eye, often removing enhancements to your data will result in the image appearing dark and hard to see. When the same file is opened in most software packages such as ArcGIS or Photo Shop it will not be optimized and will appear dark. In Focus you can customize your image and then export it scaled to 8 bit depth with the visual enhancements preserved so that when viewed it will appear the way that you want it to.

• In Focus set customize your image with the desired enhancement to appear how you wish it to be viewed.

• Right click on your file name (under the maps tab) and select Save As option.

• In the Save As window, select your output file name, the file format and the bands that you wish to include in your new file.

• Next select the Properties… button for each layer to customize the Output Later Properties.

• In the Output Type select the bit depth to scale your image to and in the Scaling Option box choose VISUAL option and select OK (repeat for each layer).

• Click the Save button to create the new file and when you open it in another software package then it should appear the way that you want it to be viewed.

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Q) How can I export the same image channel from an existing file into a new image in Focus?

A) If you need to have the same image data in two channels of an RGB image file (e.g. your new image may need to be created with a 3,2,2 setup) then you will need to use the Save As option or the Transfer Layers option from File Utility. The Translate (or Export) option will not work because it will only allow you to export one of each channel.

• In the Save As window, select your output file name, the file format and the bands that you wish to include in your new file. (Optional: select the Properties… button for each layer to customize the Output Later Properties.).

• Choose what input layers you wish to have as your output RGB layers and then click the Save Button.

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Q) How do I add or delete layers to my file in Focus?

A) In Focus switch over to Files Tab and right click on the file that you wish to add or delete layers to/from. To Add New layers choose New, the data channel type you wish to add and then the number of each channel or segment you wish to add. To delete a channel or segment, simply right click on it and choose delete.

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Q) How do I create a Bitmap from my polygon vectors?

A) Load your polygon layer into Focus, then from the Algorithm librarian find the POLY2BIT command. Setup the input and output ports and then the pixel size for the bitmap and click run to continue.

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Q) How can I remove the graticule lines from my grid on my map layout but retain my numeric values in Focus?

A) In Map mode, add a grid to your map surround and then open the properties window for that feature. Switch to the Layout tab and then select the radio button under Display to None and check the radio button to Show border.

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Q) How can I export my classification to a Shape File?

A) A shape file is a vector format but your classification results are in a raster format. Therefore all you basically need to do is to convert the raster to a vector format and then extract and attach the classification classes as attributes of the vector file.

• The RAS2POLY command found from the Algorithm librarian will allow you to convert your raster image to an equivalent vector layer. Setup the input and output ports, the output polygon type and then click the Run button to begin.

• Locate VIMAGE command from the Algorithm librarian. Use your classification image as the Input Image Layer and your resultant vector layer from the RAS2POLY process as your Input Vector Layer, specify your output options, and the output column name to store the attribute for the classification results. Click the Run button to create your output file.

• Export your resultant vector file to Shape File with Save As or Translate from the File Utility.

This procedure could also be performed with Modeler and all three steps could be combined into one process and also batch processed if you had multiple files that needed to be exported.

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Q) How can I make my black "No Data" region transparent so that it does not cover my other data layers?

A) Using the Layer Manager (found from under Layer on the main menu) you can specify any raster value (or a range of values) to make all occurrences of that DN value(s) to become transparent. For example when you create an orthophoto in Ortho Engine any non image data will be given a value of 0. If you make all 0 values of this image transparent then you can overlay it with other imagery and compare the fit of the ortho.

This can also be accomplished by right clicking on your file while under the Maps tab and opening the RGB Layer properties. In the RGB Layer properties window switch to the Display tab and you can specify the transparent value(s).

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Q) What does PCIDSK Linking do?

A) The Link utility protects your source data by creating a new empty PCIDSK database file and allowing indirect access to the original imagery on both GDB-supported and PCIDSK files.

Auxiliary information, such a LUTs or bitmaps are transferred to the newly created PCIDSK file. Linking files allows several users to work with data while preserving the integrity of the original source files. You can access data across a network or on the same system disk without duplicating large files. Imagery is not copied or transferred; instead, pointers are created to describe the directory location and layout of data. Changes are saved to the linked file only.

The link file copies auxiliary information such as LUTs, PCTs, bitmaps, vectors, and georeferencing information into a new file but does not copy the original image data. You can link to a remote source file, select a destination file, and set overview options.

1. From the File menu, select Utility and then Link.

2. In the PCIDSK Link window, click the Browse buttons to setup the input source file and a file name and location of the output file.

3. Select an overview option from the Overview options list box and click the Link button.

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Q) How do I generate a profile cross section of my terrain layer in Focus?

A) The profile tool under Layer on the main menu will allow you to generate a cross section of your image in Focus.

1) Open the Profile tool, from under layer on the main menu. From the File menu, select Utility and then Link. A default line will be added to the Focus viewer and a Profile graph and a Profile Table Window will open up.

2) You can edit the default vector line, add a new vector or load an existing one to use for your profile source. Select the vector to use with the profile with the Select Tool and the profile graph and table should change to contain the values of the desired vector.

To export your profile information, you can:

• Save your graph as a PCIDSK (.pix), TIFF (.tif), bitmap (.bmp), or PostScript (.ps) file through the Graph Controls dialog box.

• Print the profile graph by clicking Print at the bottom of the Graph Controls dialog box.

• Save your profile table to a text file through the Profile Table dialog box. This text file can be imported to any spreadsheet for editing or analysis.

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Q) Can I collect GPS data directly into Focus?

A) The GPS tool found can be used to collect GPS point data or stream a vector line from GPS point data. Before the GPS tool can be accessed, a connection must be set. The GPS receiver connection is setup through the Focus Options dialog box found under Tools on the main menu. Once the GPS receiver connection is set, the GPS tool can then be used.

1. Ensure a GPS connection has been established.

2. Open an Area in Focus containing appropriate georeferencing information, or define a new one.

The Area georeferencing bounds should correspond to the area where the GPS receiver is located (If the receiver is outside of these bounds then you will not be able to update the cursor or collect new vectors).

1. From the Tools menu, click GPS Tool.

After the GPS tool becomes active, you will be able to update the cursor position or add new vector data to your project.

To input vector point data using a GPS receiver:

1. (After activating the GPS connection) From under the Maps tab right-click the Area and click New Vector Layer.

2. In the New Vector Layer window, choose the Point option and click OK.

3. In the Maps tree, select the new point layer that you have just created.

4. On the Editing toolbar, click the New Shapes icon and choose Points.

5. From the Tools menu, click GPS Tool.

6. In the GPS Tool dialog box, click one of the following buttons:

Capture Stream — updates the new point layer with a point determined by the location of the GPS receiver

Capture Point — adds new points to the vector layer at a specified stream interval. You can continue to collect points by repeatedly clicking the button.

1. Click Finish, right click on your vector layer and select Save to preserve the new data.

To input vector line or polygon data using the GPS receiver:

1. (After activating the GPS connection) From under the Maps tab right-click the Area and click New Vector Layer.

2. In the New Vector Layer window, choose one of the following options in the Layer Type area: Line / Topological Line / Polygon /Topological Polygon and click OK.

3. In the Maps tree, select the new layer that you have just created.

4. In the GPS Tool dialog box, click one of the following buttons:

Capture Stream — adds a new vertex to the vector layer at the specified stream interval. New vertices are added to the line or polygon until you click Finish.

Capture Point — adds only the initial vertex to the line or polygon layer. You can continue to collect vertices for the line or polygon with each click of the button.

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Q) What is the overview window and how do I enable it?

A) If you have a very large image file open or if your image is zoomed in, you can pan around the image in the view pane. There are two ways to pan around images: you can click the Pan button (small white hand) in the Focus toolbar or you can use the bounding outline in the overview window. The extents for the overview window are based on the extents of all data loaded in the main viewer regardless of what data types you set to be shown.

When you open image data in Focus, the overview window shows a smaller version of the image in the view pane. The overview window has a bounding outline that you can use to control the view in the view pane. You can click the bounding outline to pan around the image in the view pane and you can resize the bounding outline to zoom the image in the view pane.

To enable the overview window:

1. Open the Focus Options window from Tools on the main menu.

2. Click the check box beside Overview window in the Show section of the General interface options and click Apply.

To zoom using the overview window:

1. In the overview window, pointer to a corner of the bounding box.

2. Drag the bounding box to a new size.

Dragging the box in the overview window moves the image in the view pane without changing the zoom level.

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Q) How do I enable vector snapping when I am creating new lines?

A) You will find the controls for creating and editing vectors in the Focus Options window in the Vector Editing section. The Vector editing option sets the units and tolerances for Search, Snap, and Weed vertices tolerances. This option also sets the snap feature for digitizing operations.

1. Open the Focus Options window from Tools on the main menu.

2. Switch to the Vector editing section by clicking on Vector editing from the selection tree on the left hand side of the window, the right side will then switch to allow you to customize your editing preferences.

3. Type a value in the Snap tolerance box and then choose a measurement unit from the list box.

4. Enable the Snap automatically check box to activate the snap operation (You can still activate or deactivate the snap operation by holding the Alt key while starting or ending a line or starting an area).

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Q) How do I set up a Digitizing Tablet in Focus?

A) You can connect a digitizing tablet to your system and use it with Focus. The Digitizing Tablet option found in the Options Window from the Tools section of the main menu allows you set up a digitizing tablet.

Before using a digitizing tablet, you must connect it to the computer and set up the software to communicate with the tablet. Focus supports Wintab and provides several other tablet drivers.

To do set up a digitizing tablet using Wintab:

1. Ensure the digitizing tablet is connected according to the manufacturer’s instructions.

2. From the Tools menu, click Options to open the customizable Options window.

3. Select Digitizing Tablet from the selection tree on the left hand side of the window.

4. Enable the Wintab device option radio button. If your device is Wintab enabled, The option will be enabled by default, and the device setup area will be populated with the Wintab settings.

5. Enter the values of components by reading them from Wintab and then click Test Connection.

To set up a digitizing tablet using a driver:

1. Ensure the digitizing tablet hardware is connected according to the manufacturer’s instructions.

2. From the Tools menu, click Options to open the customizable Options window.

3. Select Digitizing Tablet from the selection tree on the left hand side of the window. By default, the Generic device option is selected, and the Wintab device option is unavailable.

4. Choose a hardware communication port from the Device list box.

5. Choose a driver that matches your device from the Tablet list box (Note that the SummaSketch III digitizer is no longer supported, however, the ASCII BCD report format is supported).

6. In the Communication settings area, choose a baud-rate, data-bit, parity, and stop-bit value from the appropriate list boxes, according to the digitizing tablet manufacturer specifications and then click Test Connection.

The setup is successful if a device string appears in the Device String box in the Digitizing Tablet Connection Testing dialog box. If no device string displays, click OK to reset the device setup and communication settings.

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Q) What types of MetaData is supported in Focus?

A) Focus uses the following metadata tags for raster layers:

• DEFAULT_PCT_REF - Reference to the pseudo-color table (PCT) segment for displaying an image in pseudo-color mode. This entry defaults the image to pseudo-color display mode.

• DEFAULT_LUT_REF - Reference to a look-up table (LUT) segment for a default enhancement when displaying an image.

• SCALING_MIN - Default value to use as a minimum for scaling an image channel to 8-bit for display purposes.

• SCALING_MAX - Default value for maximum scaling in an image channel to 8-bit for display purposes.

• NO_DATA_VALUE - Image value indicating no data is available.

• ELEVATION_UNITS - May be UNKNOWN (implicit default), FEET, or METRES. Primarily intended for use with elevation channels and should be UNKNOWN for non-elevation data.

• Class_n_Name - Short name for a theme class in a raster with "n" being the class number. Should be less than 9 characters.

• Class_n_Desc - Longer description for a class in a raster.

• Class_n_Color - Color for displaying a particular theme class. Value is the color encoding using the RGB (rrr ggg bbb) convention as seen in the PCLColor class.

• ACQUISITION_DATE - Date and time an image was acquired. The format of date is YYYY/MM/DD HH:MM:SS.

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Q) What are Pseudo Color Tables (PCT)?

A) PCT segments contain an array of 256 colors and assigns color values to 8-bit images. A PCT always contains exactly 256 entries. File formats, such as TIFF, which may have color tables with less than 256 colors, assigns a value of zero to unused colors. There is no support for alpha channels in the table.

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Q) What are Bitmap Segments?

A) Bitmap segments are binary pseudo-images (raster grids) similar to image layers, and must have the same number of pixels and lines as other raster layers in the database however each pixel of the bitmap is only 1 bit. In other words, the DN value of the bitmap pixel can be either zero (pixel not "on") or 1 (pixel "on"). Bitmap pixels with a value of 1 are visible (they take on the color of the graphic plane). The georeferencing associated with the raster layer is assumed to apply to bitmap layers as well. Bitmaps are used most commonly for delineating masks or creating training areas in classification.

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Q) What are Orbit Segments?

A) Orbit segments hold satellite ephemeras data, used in the orthorectification process. This information is read from the original data source, or from a text file.

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Q) How can I convert my data to a different format to use with other software packages?

A) Geomatica allows you to export (or translate) data from one GeoGateway supported file format to another or create a new PCIDSK file from a GeoGateway format using only the layers you specify. This feature is available from all programs of the Geomatica suite and is found under Translate from the File menu in Focus. In the Translate File dialog box you select similarly georeferenced source and destination files and then share layer information between the two files.

1. From the File menu, click Utility and then Translate.

2. In the Translate (Export) File window, select the Source file and the Destination file as well as the location for your files.

3. Select the format you want to use from the Output format list box.

4. In the Source Layers area, select the data files that will make up your destination file from the View list box.

5. Select an item from the Source Layers list and click Add. You can remove a layer from the Destination Layers list by selecting it and clicking Remove.

6. Click Translate.

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Q) How do I import ASCII data in Focus?

A) The Import ASCII Table/Points Wizard allows you to import ASCII files into a project and convert them into vector-point data. Table values that combine coordinates with field research data can be imported to the Attribute Manager spreadsheet and converted into vector-point files that you can add to a project and open as layers in the view pane. For more information on this process refer the following tutorial:

http://www.pcigeomatics.com/products/Creating_LIDAR_surface_from_ASCII.pdf

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Q) How can I open data from a remote data source in Focus?

A) You can open data from an Oracle database, a Web service, a URL, and through Open Database Connectivity (ODBC) as long as the data formats are compatible with GDB technology.

Focus supports read and write access to Oracle8i and Oracle 10g Spatial. For more information, refer to "ORACLE" in Supported File Formats under Technical References in the Geomatica Help.

A Web service provides access to data published on the servers connected to the Web. You can access any Web mapping service (WMS) or Web feature service (WFS) complying with the OGC Web Mapping or Feature Service specifications, and display the data as a layer in the Focus project. The data is read-only

To open data from the Web or a database:

1. From the File menu, click Open.

2. In the File Selector dialog box, click Remote Data.

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Q) Can I use undefined Image data in Focus?

A) You can open undefined or raw image data the same way you would any other file. In the File Selector dialog box, locate and select your raw imagery and click Open.

When you open raw images the Raw Imagery File Definition dialog box opens automatically, allowing you to define the raw imagery file format. The following controls are available to define data:

Header Bytes Specifies the number of bytes to allocate for header information. The zero value, indicates that imagery data starts at the very beginning of the file.

Image Size defines the X (Pixel) and Y (Line) size of the image file. These should be the full size of the image in the file, even if you only wish to open a sub-set of the file.

Number of Channels Indicates the number of channels or planes of image data stored in the file.

Data Interleaving Indicates how multiple channels of image data are interleaved. This field is not applicable for one channel image files. However, single-band data can have band interleaving.

PIXEL: The channels are pixel interleaved. For example, in a three-channel file, the values in the file are 123123123..., with the channel values for a given pixel located together.

LINE: The channels are line interleaved. The data for line 1 of the first channel occurs first, followed by the data for line 1 of the second channel and line 1 of the third channel. Next is line 2 of the first channel, and so on. For example, in a three-channel file, the values in the file would be (line 1) 111...222...333, (line 2) 111...222...333, and so on.

BAND: The channels are band sequential. All the data for the entire first channel would be first, followed by all the data for the second channel, and so on.

Data Type: 8-bit Unsigned, 16-bit Unsigned, 16-bit Signed, or 32-bit Real

Byte Order options for storing the order of multiple-byte data words. Used for non-8-bit image data only, it can be ignored for files containing only 8-bit data.

Least Significant Byte first (LSB) is common on IBM computers with Intel 80 x 86 architecture. It is sometimes known as swapped or little endian. In LSB order, a 16U-pixel value of 1 would be expressed as two bytes, the first a 1, and the second a 0.

Most Significant Byte first (MSB) is the order common on Sun, IBM, RS/6000, HP, SGI, and Mac systems. It is also known as unswapped, big endian, or Motorola order. In MSB order a 16U-pixel value of one would be expressed as two bytes, the first a zero, and the second a one. The default selected on the panel is the byte order of the local system.

To save raw configurations:

• In the Raw Imagery Definition dialog box, click Accept.

A new header file is created with the file name extension .aux.

The new raw configuration file is an auxiliary file that contains layout information for the imagery that you provide. Focus automatically recognizes the new raw file without redefining it.

Once the .aux file is created, you cannot define the raw file again until the .aux file is deleted. When experimenting with possible raw file definitions, an .aux file is not recommended.

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Q) How do I clip files in Focus?

A) Clipping data is an effective method to working with large data sets. In research and testing situations, you may want to create subsets of a large data base. By working with small representative areas, you can reduce processing times or you can use file subsets to test an image process. When you obtain a promising result on a subset, you can repeat the process on a larger, more complex scene.

To clip or subset a file:

1. From the Clipping/Subsetting window (found under Tools on the main menu), choose input file (If the file is not listed, click Browse and choose a file from the File Selector dialog box).

2. Enable the layers from the file that you want to include with your clipped image from the Available Layers list. A check mark indicates the layers that will be clipped, no check mark indicates that it will not be included.

3. In the Output area, choose a new file name, location for the file, and select the file format that you want (you can specify options for the format by clicking Options and select options from the GDB Options Editor).

4. Enter a value that you want to use for pixels without data in the output file in the Initialization Value box. Use a value that does not occur in the image being clipped. If you want to give the initialization value the metadata tag of no data, enable the Set as No Data Value check box.

5. Depending on how you want to use to clip the image, select one of the following options from the Definition Method list box:

User-entered Coordinates — enters the corner coordinates for the clip region. All layers will be clipped to fit that region.

Select a File — uses a smaller, intersecting file to define the bounds of a subset.

Select a Clip Layer — uses a smaller, intersecting layer from a file to define the bounds of a subset.

Select a Named Region — bases the clip on a named region you created in Focus.

Select a Script Subset File — creates several clip regions on the same image. You can create a text file containing the coordinates and the output file name; Focus automatically produces the series of subset files.

Use Current View — bases the clip on the region displayed in the view pane (only available from Area view)

1. Click the Clip button once all parameters have been set to clip your image.

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Q) What is the Data Merge Wizard in Focus?

A) The Data Merge Wizard allows you to combine a group of files, regardless of bounds, projection, data type, or resolution into a single output file. When you start the Data Merge Wizard, simply follow the instructions at the top of the wizard dialog boxes for each step. The following information gives an outline of how to add information to each of the Data Merge Wizard dialog boxes.

If a layer does not have a proper projection, it will not be available; however, LUT, PCT, and GCP layers can be transferred even if the source files have no georeferencing. A warning message opens when georeferencing is not compatible.

The Data Merge Wizard has three steps: choosing input layers, setting the output and georeferencing, and setting up output layers.

Open the Data merge wizard from Tools on the main menu by clicking Data Merge.

 In the Data Merge window, click Browse to locate the file you want to add and click open to add the layers from that file to the Available Files/Layers list.

In the Available Files/Layers list, enable a check mark next to any layer that you want to add as an input layer and then click the next button to continue.

Provide a name and file location for your output file or choose an existing file (Existing files are not over written, the merged data is added to the existing file).

Choose an output file format from the Output format list box (with any options that may be needed from the Options box).

In the Georeferencing Setup area, define the following items for your file: Projection, Extents, and the Resolution.

In the Reprojection Parameters section choose the sampling settings and then click next to continue.

Step 3 of the Data Mege Wizard is a summary of your data before the merge, this window allows you to make any final changes before executing the process. The layer order that you see is the order in which layers will be merged to the output file. By default, the order is what was selected in the Choose Input Layers step. To change the order, drag a layer up or down the list. To rename a layer, right-click the layer and click Rename. To remove a layer, right-click the layer and click Remove.  To edit parameters, double-click a layer in the Select Layer(s) list. A parameters dialog box opens for the selected data type.

Once all settings have been set click the Finish button to begin the process.

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Q) What is the Smart Digitizer tool?

A) The Smart Digitizer is a semi-automatic digitizing tool created by GeoTango International Corporation that uses a pattern-recognition process to quickly extract feature lines and polygons from a wide variety of remotely sensed images, such as high- and low-resolution satellite imagery, aerial photos, optical images, hyperspectral images, and radar data. Its line-fitting algorithm greatly reduces the number of points that you must digitize in order to capture the outline of a feature and produces a better approximation of image features than the straight-line segments gathered between manually entered points. The Smart Digitizer is available only if you have a license for it.

You can use the Smart Digitizer to digitize polygonal, thin-line, and thick-line features. Polygonal features are regions within an image and include lakes, buildings, classes in a thematic image, agricultural fields, and so on. For more information on the Smart Digitizer see the following quick guide (http://www.pcigeomatics.com/services/support_center/quickguides/Working_with_Smart_Digitizer.pdf) or refer to Geomatica Help. 

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Q) What does Clone View do in Focus?

A) A Clone View window is a separate opened window for the current project that is connected through your main Focus Maps and Files trees in the view panel.  You can use this feature for several tasks. For example, if you want to compare classified images with reference images or if you want to analyze multi-temporal imagery, you can use Clone View to open several independently enhanced versions of the same image to help discriminate certain features.

When you have an open Clone View, you can use the Chained Window command to have the cursor position in the Focus view panel automatically control the cursor position in the Clone view, vice versa, or have both cursors affect each other.

To chain a Clone View window:

1. Select Clone View from View on the main menu in Focus.

2. If you want the cursor in the Focus view panel to follow the cursor in the Clone view, click the Chained Window button on the Focus toolbar.

3. If you want the cursor in the Clone view to follow the cursor in the Focus view pane, click the Chained Window button on the Clone view toolbar.

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Q) What are Named Regions?

A) Named regions are similar to “book marks” of web browsers where you can define a certain area in your view panel and then come back to the same location later on. You can create custom views of your map or image with the Named Regions tool.

New named regions are defined by upper-left and lower-right corner coordinates. You can define the boundaries of a new region by using either the zoom tools on the Focus toolbar or by using the advanced features of the Named Regions dialog box. You can save your named regions when you save the current project. If you add, remove, or edit the name of a Map or Area in the Maps tree, the information is updated in the Named Regions tree.

To create a named region:

1. In the Focus viewer window zoom to a desired area of your image with any of the zoom tools to define your region.

2. Click the Named Regions icon to open the Named Regions window.

3. Click the + button, enter a name to define the selected region in the Named Region 1 box and click OK

4. When you want to return to a defined area, Click the Named Regions icon and choose a defined Region from the window that you created and click OK. The Focus window should revert to your saved view.

To remove a named region:

1. Click the Named Regions icon to open the Named Regions window.

2. Select an existing named region, click the – button and click OK (You can also right-click a named region in the Named Regions tree and click Remove).

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Q) How to use a math Model with an Image?

A) A math model is a mathematical relationship used to correlate the pixels of an image to correct locations on the ground accounting for known distortions. Different sensors require different math models to correct the distortions.

Math models can come from a number of sources. QuickBird, Ikonos, and OrbView imagery can come with a text file that contains rational function coefficients called Image Geometry Model (IGM) or Rapid Positioning Capability (RPC), which Focus uses to define a Rational Functions math model. You can build a math model in OrthoEngine and export it as a segment in the file containing a raw image. Geomatica also contains algorithms that can build math models. These algorithms can be run in Modeler, EASI, or in the Algorithm Librarian:

• SATMODEL: to compute Toutin's Model, which is a rigorous satellite math model.

• RSMODEL: to compute the ASAR and RADARSAT-specific math model.

• RFMODEL to compute the Rational Functions math model.

• AVMODEL: to compute the math model for AVHRR imagery.

• OEMODEL: to compute any model from an OrthoEngine project file.

When you open an image containing a math model segment, you can choose to use the file georeferencing or math model. When you choose file georeferencing, the image opens in a layer in an Area using the georeferencing saved in the file or pixel-based georeferencing if no georeferencing is available. When you choose the math model, the image is displayed as a layer and the Area is changed to a Math Model Area. In the Math Model Area the image is displayed without correction in the viewer, but accurate ground coordinates are calculated for each pixel using the pixel and line coordinates, the math model, and the digital elevation model (DEM), or an approximate elevation value that you provide.

The advantage of using the math model is that you can display geocoded coordinates, overlay geocoded vectors, and digitize geocoded three-dimensional vectors on the raw image instead of going through the potentially time-consuming, labor-intensive process of orthorectifying or geometrically correcting the imagery. This process is also known as mono-restitution.

To open an image with a math model:

1. Open an image file

2. If you want to use the georeferencing saved in the file, click File.

3. If you want to display the image using the math model associated to the file, click Math Model.

4. Click OK.

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Q) Can I create a map that is not rotated north up?

A) One of the improvements of Geomatica v10 Focus over its predecessors is the ability to rotate your map. Some image formats support raster rotation, which can display the raster as spun in a particular position, usually so North is at the top of the viewer. Currently, PIX, GeoTIFF, MrSID and JPEG2000 can store rotations internally. TIFF (with .tfw), JPEG (with .jpw), BIP (with .biw), BIL (with .blw) and NITF (with .niw) support rotations via their associated world file. Other formats may support rotations via a PCI Geomatics .aux file.

When you open a raster that contains a rotation, you will be prompted to choose whether you want the raster to display as a rectangular grid (Raster Up) aligned with the Area or with the rotation from the file (North Up).

With the North Up option, the rotated raster opens as any other raster. In the Focus view pane the raster may appear turned in the Area since it has been corrected so North is at the top of the viewer.

With the Raster Up option, the Area is rotated to counteract the effect of the rotation in the file so the first pixel in the data is in the top left corner of the Area. In the Focus view pane the raster appears squared to the Area.

When you create a map with a rotated Area (Raster Up), two surround elements are affected: Grid and North Arrow. You cannot create a grid in a rotated Area. When you create a North Arrow in a rotated Area, the North Arrow will be rotated by the amount set in the Area properties.

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Q) How do you combine several vector layers into one?

A) A combined vector layer amalgamates several vector layers into one. For example, one vector layer covering the eastern US can be combined with another layer covering the western US to produce a virtual single layer for all of the US. When you combine layers, data is not duplicated, it is linked. The combined layer does not store data but acts as a pointer to the source data.

You can combine vector layers from your current data files and from other source files with a two-part process to locate and choose the data you want to combine.

To combine layers:

1. With at least two PCIDSK files open in the control pane, click the Files tab.

2. In the Files tree, right-click the file folder icon and click New and then click Combined Vector Layer.

3. In the Combined Layer dialog box, click Browse.

4. From the Select Layer dialog box, select a file from the File list box.

5. Select an available layer from the Layers available list.

6. Click OK.

The layers and