ikonos sensor model support tour guide

IKONOS Sensor Model SupportTour Guide

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IKONOS Sensor Model Support / iii

/ ivIKONOS Sensor Model Support

Table of Contents / vIKONOS Sensor Model Support

Table of ContentsTable of Contents . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . v

Preface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . viiAbout This Manual . . . . . . . . . . . . . . . . . . . . . . . . . . vii

Documentation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . vii

Conventions Used in This Book . . . . . . . . . . . . . . . . . vii

Introduction to IKONOS Sensor Model Support . . . . . . . . . . . . 1Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1

IMAGINE Advantage IKONOS Support . . . . . . . . . . . . . . . . . . 3Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3

Select the Image . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3

Prepare Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4

Set Up the Geometric Model . . . . . . . . . . . . . . . . . . . . 5

Ortho Resample the Image . . . . . . . . . . . . . . . . . . . . . 8

View the Orthoimage . . . . . . . . . . . . . . . . . . . . . . . . . 9

Close the Files . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10

Conclusions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11

Next . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11

LPS Project Manager IKONOS Support . . . . . . . . . . . . . . . . 13Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13

Create a New LPS Project . . . . . . . . . . . . . . . . . . . . . 13Prepare the Block File . . . . . . . . . . . . . . . . . . . . . . . . . . . 13Select Model and Provide Information . . . . . . . . . . . . . . . . 15

Add Data to the Block . . . . . . . . . . . . . . . . . . . . . . . . 16

Generate Pyramid Layers . . . . . . . . . . . . . . . . . . . . . 18

Check the RPC File . . . . . . . . . . . . . . . . . . . . . . . . . . 19

Check the Frame Properties . . . . . . . . . . . . . . . . . . . 21

Ortho Resample the Images . . . . . . . . . . . . . . . . . . . 22

View the First Set of Orthoimages . . . . . . . . . . . . . . . 26Check the Registration . . . . . . . . . . . . . . . . . . . . . . . . . . 27

Start the Point Measurement Tool . . . . . . . . . . . . . . . 29Add Control Points . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29

Start Auto Tie . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33

Refine the Model with Polynomials . . . . . . . . . . . . . . 34

Ortho Resample the Images . . . . . . . . . . . . . . . . . . . 36

Compare the Results . . . . . . . . . . . . . . . . . . . . . . . . . 38Check the Registration . . . . . . . . . . . . . . . . . . . . . . . . . . 39

Table of Contents / viIKONOS Sensor Model Support

Check Results in LPS . . . . . . . . . . . . . . . . . . . . . . . . 40

Conclusions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43

Next . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43

LPS Automatic Terrain Extraction IKONOS Support . . . . . . . 45Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45

Create/Open a Block File . . . . . . . . . . . . . . . . . . . . . 45

Set DTM Extraction Properties . . . . . . . . . . . . . . . . . 47

Select Advanced Properties . . . . . . . . . . . . . . . . . . . 48General Tab . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48Image Pair Tab . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49Area Selection Tab . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50Accuracy Tab . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51

Generate the DTM . . . . . . . . . . . . . . . . . . . . . . . . . . 52

View the DEM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53

Check the Contour Map . . . . . . . . . . . . . . . . . . . . . . 54

Check the DTM Point Status Image . . . . . . . . . . . . . 55Arrange Layers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55Check Attributes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 56

Ortho Resample the Images . . . . . . . . . . . . . . . . . . 57

Close the Project . . . . . . . . . . . . . . . . . . . . . . . . . . . 57

Conclusions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57

Stereo Analyst IKONOS Support . . . . . . . . . . . . . . . . . . . . 59Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 59

Start Stereo Analyst . . . . . . . . . . . . . . . . . . . . . . . . 59Start from ERDAS IMAGINE . . . . . . . . . . . . . . . . . . . . . . . 59

Load IKONOS Images . . . . . . . . . . . . . . . . . . . . . . . 60

Use of the IKONOS Block File . . . . . . . . . . . . . . . . . . 61

Conclusions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 62

Index . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63

Conventions Used in This Book / viiIKONOS Sensor Model Support

Preface

About This Manual The IKONOS Sensor Model Support Tour Guide contains a few tour guides that help you begin to use IKONOS data in various programs.

Documentation This manual is part of a suite of on-line documentation that you receive with ERDAS IMAGINE software. There are two basic types of documents, digital hardcopy documents which are delivered as PDF files suitable for printing or on-line viewing, and On-Line Help Documentation, delivered as HTML files.

The PDF documents are found in <IMAGINE_HOME>\help\hardcopy. Many of these documents are available from the Leica Geosystems Start menu. The on-line help system is accessed by clicking on the Help button in a dialog or by selecting an item from a Help menu.

Conventions Used in This Book

In ERDAS IMAGINE, the names of menus, menu options, buttons, and other components of the interface are shown in bold type. For example:

“In the Select Layer To Add dialog, select the Fit to Frame option.”

When asked to use the mouse, you are directed to click, double-click, Shift-click, middle-click, right-click, hold, drag, etc.

• click — designates clicking with the left mouse button.

• double-click — designates clicking twice with the left mouse button.

• Shift-click — designates holding the Shift key down on your keyboard and simultaneously clicking with the left mouse button.

• middle-click — designates clicking with the middle mouse button.

• right-click — designates clicking with the right mouse button.

• hold — designates holding down the left (or right, as noted) mouse button.

• drag — designates dragging the mouse while holding down the left mouse button.

The following paragraphs are used throughout the ERDAS IMAGINE documentation:

These paragraphs contain strong warnings.

Conventions Used in This Book / viiiIKONOS Sensor Model Support

These paragraphs provide important tips.

These paragraphs describe software-specific information.

These paragraphs provide information about Leica Geosystems products.

These paragraphs lead you to other areas of this book or other manuals for additional information.

NOTE: Notes give additional instruction.

Shaded BoxesShaded boxes contain supplemental information that is not required to execute the steps of a tour guide, but is noteworthy. Generally, this is

Introduction / 1IKONOS Sensor Model Support

Introduction to IKONOS Sensor Model Support

Introduction This tour guide demonstrates how IKONOS satellite imagery can be used for single frame orthorectification (IMAGINE Advantage® Geo-correction Tool), rational polynomial coefficient (RPC) refinement and multi-image orthorectification with LPS Project Manager, automated digital terrain model (DTM) extraction with LPS Automatic Terrain Extraction, and 3D stereo viewing and feature collection with Stereo Analyst™.

In order to accurately create or extract geographic information from raw IKONOS imagery, the image geometry model (IGM) must be included with the imagery. The IGM consists of several metadata files. The metadata files contain RPCs, which are a series of coefficients used to describe the relationship between the image as it existed when captured and the Earth’s surface.

With the availability of RPCs, the IKONOS imagery can be used to accurately create orthorectified images, digital stereo models (DSMs), and DTMs without the need for ground control points (GCPs). If a higher degree of accuracy is required for a specific mapping project, the RPCs can be refined using GCPs. LPS Project Manager allows for the refinement of an IKONOS IGM using GCPs.

For more information about IKONOS sensor model support in IMAGINE Advantage, LPS Project Manager, Stereo Analyst, and LPS Automatic Terrain Extraction, see the On-Line Help.

For the most recent information about IKONOS sensor model support in Leica Geosystems products, visit our web site at www.gis.leica-geosystems.com.

Introduction / 2IKONOS Sensor Model Support

Select the Image / 3IKONOS Sensor Model Support

IMAGINE Advantage IKONOS Support

Introduction In this tour guide, you can see how to use the IMAGINE Advantage Geometric Correction tool to perform single frame orthorectification.

Approximate completion time for this tour guide is 15 minutes.

The steps you are going to perform in this tour guide include:

• View and select the image to be resampled.

• Set the geometric model parameters.

• Resample the image.

• View and evaluate the output orthoimage.

Select the Image To execute the steps in this tour guide, you must supply your own data: the data used in this example is not included with IKONOS sensor model support. However, the steps in this tour guide are applicable to any IKONOS data.

The IKONOS 4-meter data in this example is of San Diego, California, USA.

1. Start ERDAS IMAGINE®.

2. Click the Viewer icon on the ERDAS IMAGINE icon panel.

NOTE: You may be prompted to choose either the Classic Viewer or the Geospatial Light Table.

3. Click the Open icon to open a File Selector.

4. Navigate to the directory that contains the image you want to resample.

This installation only supports IKONOS images that are in TIFF (*.tif) format.

5. Select the image and click OK in the File Selector.

The image to be resampled displays in the Viewer.

Prepare Data / 4IKONOS Sensor Model Support

This image is in file (pixel) coordinates. You can use the Geometric Correction tool to resample the image into the Geographic Lat/Lon projection.

Prepare Data You can access the geo-correction tools via the Data Prep icon on the ERDAS IMAGINE tool bar.

1. Click the Data Prep icon on the ERDAS IMAGINE icon panel.

The Data Preparation menu opens.

This is an IKONOS image of San Diego, California. Currently, the data is in file coordinates only. You can use the geo-processing tools in IMAGINE Advantage to orthorectify the image.

IKONOS Sensor Model Support Set Up the Geometric Model / 5

2. From the Data Preparation menu, select Image Geometric Correction.

The Set Geo Correction Input File dialog opens.

3. Confirm that the From Viewer radio button is selected.

4. Click the Select Viewer button.

You are prompted by an instruction dialog to left-click in the Viewer containing the image you want to resample.

5. Click in the Viewer containing the IKONOS image.

Set Up the Geometric Model

Once you specify the image to orthorectify, the Set Geometric Model dialog opens.

Click to select Image Geometric Correctionfrom the menu

Since you opened the mage to be orthorectified n a Viewer, this option is lready selected for you

Click Select Viewer specify the image

Set Up the Geometric Model / 6IKONOS Sensor Model Support

1. In the Set Geometric Model dialog, select IKONOS from the list.

2. Click OK in the Set Geometric Model dialog.

The Geo Correction Tools and IKONOS Model Properties dialogs open.

The IKONOS Model Properties dialog is where you define the metadata associated with the image you want to resample. The information you need is in the RPC file. By default, the software looks in the same directory as the one that holds the image to find the RPC file. If it finds an RPC file name that matches the image, it is loaded in the RPC File field for you.

Select IKONOS from the list of geometric models

The rational polyno

Without GCPs,

coefficients file isselected for youif it is in thesame directory asthe image

you do not needto specify apolynomial order

IKONOS Sensor Model Support Set Up the Geometric Model / 7

3. Review the settings in the Parameters tab of the IKONOS Model Properties dialog.

The higher the polynomial order, the more known points you must have in the image. Since there are no GCPs collected for this data, the refinement with polynomials option is ignored.

You can specify an Elevation Source to improve the results of the resampling process. Either enter a Constant average value for the scene, or use a DEM to provide elevation information.

The Elevation Value, Elevation Min/Max, and Elevation Units are derived from the metadata file that accompanies IKONOS images. If you have a DEM file for the area covered by the image, use it for better accuracy.

You can view the metadata file in the IMAGINE Text Editor. Select Tools | Edit Text Files, then select the metadata file corresponding to your images.

4. Click the Projection tab in the IKONOS Model Properties dialog.

The projection parameters listed here are going to be applied to the output orthoimage.

RPC FilesIKONOS imagery is typically supplied with an RPC, rational polynomial coefficients, file. This file contains information that is mandatory to determining interior and exterior orientation, as well as supplemental information such as the geographic coordinates associated with the coordinates of the imagery.

NOTE: Space Imaging’s Geo Ortho Kit product includes RPC information.

The RPC file also contains information regarding the projection of the file, which is automatically incorporated into the IKONOS model at the time of image identification.

The output orthoimage will have this projection

Ortho Resample the Image / 8IKONOS Sensor Model Support

Ortho Resample the Image

Next, you use the Geometric Correction tools to resample the image.

1. In the Geo Correction Tools dialog, click on the Ortho Resampling icon.

The Resample dialog opens.

2. Click the Open icon to open a File Selector.

3. Navigate to a directory where you have write permission.

By default, output images are stored in your Default Output Directory, which is specified in the User Interface & Session category of the Preference Editor.

4. Name the file with an *.img extension and click OK in the File Selector.

5. If you wish, make changes to the Output Cell Sizes.

Click this icon to openthe Resample dialog

Name the output

Increase cell size

Ignore 0 in

file here

to speed resampling,or maintain default

statistics for a better solution

IKONOS Sensor Model Support View the Orthoimage / 9

Smaller cell sizes can potentially increase processing time.

6. Click the checkbox for Ignore Zero in Stats.

7. Click OK in the Resample dialog.

A status dialog opens, which tracks the progress of the resampling.

8. When the resampling process is complete, click OK to close the status dialog.

The presence of the status dialog after process completion is controlled by a preference, Keep Job Status Box, in the User Interface & Session category of the Preference Editor.

View the Orthoimage

When the process is complete, you can view the orthoimage in a Viewer and compare it to the original image.

1. Click the Viewer icon on the ERDAS IMAGINE tool bar.

NOTE: You may be prompted to select the Classic Viewer or the Geospatial Light Table.

2. Click the Open icon to access a File Selector.

3. In the File Selector, click the Recent button.

Select the file from the list of recent images

Close the Files / 10IKONOS Sensor Model Support

4. From the Recent list, select the orthoimage you just generated.

5. Click OK in the List of Recent Filenames dialog.

6. Click OK in the File Selector.

The orthoimage displays in the Viewer.

The image is now in the Geographic Lat/Lon projection, and is oriented correctly in the Viewer. Compare its orientation with the original image.

Close the Files

1. Close the Viewers containing the original and resampled IKONOS images.

2. If you wish, save the geometric model by clicking Yes in the Verify Save on Close dialog, and name it in the File Selector (with a *.gms extension); if not, click No.

3. Close the Data Preparation menu by clicking Close.

4. Close ERDAS IMAGINE by selecting Session | Exit IMAGINE from the icon panel.

IKONOS Sensor Model Support Next / 11

Conclusions As you have learned, the Geometric Correction tool in IMAGINE Advantage can be used to quickly orthorectify a single image. The resulting orthoimage is accurate to real-world coordinates. While GCPs were not used in this example, you can also use the GCP tool to enter reference coordinates with which to improve the accuracy of your output orthoimage.

You access the GCP tool by clicking the GCP Editor icon in the Geo Correction Tools dialog. Then you can enter reference coordinates from one of many sources.

Next Next, you can learn how to use LPS Project Manager to create multiple orthoimages using IKONOS data.

Next / 12IKONOS Sensor Model Support

Create a New LPS Project / 13IKONOS Sensor Model Support

LPS Project Manager IKONOS Support

Introduction In this section of the tour guide, you can learn how to use LPS Project Manager, which is part of the Leica Photogrammetry Suite, to perform RPC refinement and multi-image orthorectification.


The steps you are going to perform in this tour guide include.

• Create a new LPS Project Manager project.

• Select the sensor model and define block properties.

• Add imagery to the block file.

• View the RPC file.

• Orthorectify the images.

• Collect GCPs.

• Generate tie points.

• Refine the model.

• Orthorectify the images again.

• Compare results.

• Save the block file.

Create a New LPS Project

In this section of the tour guide, you can learn how to create a new LPS Project Manager block file using 4-meter IKONOS data and the associated IGM file, such as an RPC file.

This data is of San Diego, California, USA. Because of the size of the data, it is not included with this tour guide; however, the steps are applicable to any IKONOS data accompanied by the IGM, such as the GeoPlus product and the Stereo product.

Prepare the Block File

1. Start ERDAS IMAGINE.

2. Click the LPS icon on the ERDAS IMAGINE icon panel.

Create a New LPS Project / 14IKONOS Sensor Model Support

The LPS Project Manager opens.

3. Click the New File icon .

The Create New Block File dialog opens.

IKONOS Sensor Model Support Create a New LPS Project / 15

4. Navigate to a directory in which you have write permission.

5. Click in the text field next to File name, and type a name for the block file, such as ikonos_tour.blk, then press Enter on your keyboard.

6. Click OK to close the Create New Block File dialog.

The Model Setup dialog opens.

Select Model and Provide Information

The Model Setup dialog begins the next series of steps wherein you specify the sensor model to apply to the block file. In this tour guide, you are working with IKONOS data, which has a unique model.

1. Click the dropdown list for Geometric Model Category and choose Rational Functions.

2. In the Geometric Model list, click to select IKONOS.

3. Click OK to accept the geometric model and close the Model Setup dialog.

The Block Property Setup dialog opens and displays the Reference Coordinate System information.

ave the block file in a rectory where you have rite permission

Select the IKONOSgeometric modelfrom the list

IKONOS is arational functionmodel

Add Data to the Block / 16IKONOS Sensor Model Support

In the case of IKONOS data, the Projection is always initially set to Geographic (Lat/Lon). Likewise, the Datum is always set to WGS 84. You can change the projection to be associated with the block file by clicking the Set button to access the Projection Chooser dialog.

If you wish to reproject the final orthoimage, you can also do so using the ERDAS IMAGINE Reprojection utility.

The reference units associated with IKONOS data default to Degrees for Horizontal Units.

4. Click OK in the Block Property Setup dialog.

Add Data to the Block

At this stage, you supply the IKONOS data.

NOTE: You must supply your own data for this tour guide.

1. Click Images in the Block Project Tree View.

2. Click the Add Frame icon .

The Image File Name dialog opens.

All IKONOS images are initially set tothe Lat/Lon projection

Click the Images folderto add images to the block

IKONOS Sensor Model Support Add Data to the Block / 17

3. Navigate to the directory containing the IKONOS images.

4. Click the Files of type dropdown list and select TIFF.

5. From the file name list, select the first image.

NOTE: IKONOS images are usually in TIFF or NITF format. This example uses TIFF images. The IKONOS stereo imagery has already been geoprocessed to remove Y parallax.

6. Ctrl-click the second image to add it to the current selection.

7. Click OK in the Image File Name dialog.

The LPS Project Manager updates. Both of the selected images are added to the block file.

8. Click the plus sign next to Images to see the images listed.

Ctrl-click to add he second imageo the selection

Select the first image o add to the block file

Generate Pyramid Layers / 18IKONOS Sensor Model Support

Alternately, you may open an existing block file. If the images are not on-line, you should reattach them. Click the Frame Properties icon to access the IKONOS Frame Editor. There, you can use the Attach button to reattach images in the block.

Generate Pyramid Layers

Pyramid layers allow you to rapidly display images at any resolution. You can quickly generate pyramid layers for your data by clicking in the Pyr. column that corresponds to the image.

The TIFF Image Files category of the Preference Editor has an option called Edits Allowed. Check to ensure that this option is enabled when you are generating pyramid layers for TIFF images.

1. Click in the Pyr. cell that corresponds to the first image.

The Compute Pyramid Layers dialog opens. By default, the All Images Without Pyramids radio button is selected.

IKONOS Sensor Model Support Check the RPC File / 19

LPS pyramid layers are different from traditional ERDAS IMAGINE pyramid layers. LPS pyramid layers are created using the binomial interpolation technique. You must generate LPS pyramid layers to proceed.

2. Click OK in the Compute Pyramid Layers dialog to generate pyramid layers for the two images.

Once the pyramid layers have been generated, which is indicated by the status bar at the bottom of the LPS Project Manager, the Pyr. cells in the CellArray are green.

The color of the columns is controlled by a preference, Status On Color. To access the LPS Project Manager preferences, select Session | Preferences, then select LPS in the Category section of the Preference Editor dialog.

Check the RPC File Each IKONOS image is accompanied by a RPC file. This file is a text file that is typically located in the same directory as that from which you accessed your IKONOS images. The IKONOS Frame Editor dialog is used to identify and attach the RPC file associated with each IKONOS image in your block file.

Next, you are going to examine the contents of an RPC file.

1. From the Tools menu of the ERDAS IMAGINE tool bar, select Edit Text Files.

The ERDAS IMAGINE Editor opens.

2. Click the Open icon .

Each image in the block fileneeds LPSpyramid layers

e green column indicates pyramid layers have been generated

Check the RPC File / 20IKONOS Sensor Model Support

3. In the Load File dialog, navigate to the directory that contains your IKONOS data, and select the RPC text file.

NOTE: RPC files are usually named the same as the image itself, with the “_rpc” designation.

4. Click OK in the Load File dialog to open the RPC file.

The file opens in the Editor.

5. Scroll through the contents of the file.

If you remember when you were setting up the block file, the default projection of the images was set to Geographic Lat/Lon. The RPC file also includes data such as offsets and pixel scale, as well as the coefficients needed to adjust the image. This file provides the coefficient model relationship of the image to the ground. The coefficients are based on a 3rd order transformation. The coefficients are calculated from the original IKONOS sensor model definition.

6. Click File | Close in the Editor dialog.

Information in this RPC file provides LPS Project Manager(Stereo Analyst and LPS ATE) with both interior and

exterior orientation information for the image

IKONOS Sensor Model Support Check the Frame Properties / 21

Check the Frame Properties

1. On the LPS toolbar, click the Frame Properties icon .

The IKONOS dialog opens the Sensor tab, and displays the first IKONOS image in your block file. Like other types of block files, you can use the Next button to move through the images in the block to ensure that the appropriate RPC file is associated with each image. If the RPC is located in the same directory as the image file, LPS Project Manager loads it for you.

2. If it is located in a folder other than the one that contains the

IKONOS images, click the Open icon and navigate to the

directory containing the RPC file for the first image.

3. Select the file and click OK in the File Selector.

Notice that the RPC Coefficients file name matches that of the Image File Name. The minimum and maximum elevation and meters defaults are derived from the metadata file that accompanies IKONOS images.

4. Click the Next button to see the second image in the block file.

5. Again, if necessary, click the Open icon and navigate to the

directory containing the RPC file for the second image.

6. Select the file and click OK in the File Chooser.

7. Click OK in the IKONOS Frame Editor dialog to accept the images and their associated RPC files.

You are returned to the LPS Project Manager. The RPC file provides enough information to approximate the interior and exterior orientation parameters; therefore, those columns are green in the CellArray.

he RPC file associated with the particular image

identified here

Ortho Resample the Images / 22IKONOS Sensor Model Support

Ortho Resample the Images

At this point, you can resample the IKONOS images in the block file. With the coefficients, LPS Project Manager has enough information to create orthoimages. You use these orthoimages generated only from the RPC file contents for comparison later in the tour guide.

The advantage of orthorectifying in this manner is solely one of speed. The accuracy of the resulting orthoimages is within 20-40 meters of real-world objects and topography. Your accuracy is better if you take the time to collect several GCPs with which to further refine the sensor model.

1. Click in the Ortho column to open the Ortho Resampling dialog, or

click the Ortho Resampling icon .

The Ortho Resampling dialog opens:

Interior and exterior orientation information exists, and you can resample a

IKONOS Sensor Model Support Ortho Resample the Images / 23

NOTE: The following settings are appropriate for the particular data set used in this tour guide. Your data may require different settings. See the On-Line Help for more information.

2. Click in the Active Area field and type 90.0, or use the increment nudgers to the right of the field.

3. Click in the Output File Name field and type a name for the output file, or accept the default name.

4. Confirm that the DTM Source dropdown list displays Constant.

5. In this case, the value 64 is appropriate for the Constant Value field.

You can also use an external DEM to improve accuracy of the output orthoimage.

6. Click in the Output Cell Sizes fields and enter .00004 (an appropriate value for this data set) in both the X and Y fields.

NOTE: These cell sizes are measured in degrees, not meters.

7. Click the Advanced tab in the Ortho Resampling dialog.

8. Click the checkbox next to Ignore Value, and maintain the value of 0.

In lieu of a DEM covering the area, set a constant elevation value

Output cell sizes are measured in degrees

Set the active area to use a percentage of theoriginal image

Images to be resampled display in the CellArray


Now that you have the parameters set, you can add the other IKONOS image and it inherits those parameters.

9. Click the Add button at the bottom of the dialog.

In this example, there is only one additional file to add to the orthoresampling process, so clicking the Add button is appropriate. If you have multiple images, you should choose Add Multiple.

The Add Single Output dialog opens.

10. Click the Input File Name dropdown list and select the second image in the block file.

The Output File Name is automatically assigned; however, you can change it and the directory in which it is stored if you wish.

11. Click the checkbox next to Use Current Cell Sizes.

12. Click OK in the Add Single Output dialog.

The information updates in the Advanced tab.

Choose the image to add from the dropdown list


13. In the CellArray, click in the > column corresponding to the second image and scroll to see the settings.

The second image in the block file is added to the Ortho Resampling CellArray with the same parameters (for example, cell size and constant elevation value) as the first image in the block file.

You can modify the settings of each image by clicking in the > column to make the image active, then changing settings in the dialog, or in the CellArray.

14. Click OK in the Ortho Resampling dialog to start the resampling process.

A Job Status dialog opens to display the progress of the resampling.

15. When the process is complete, click OK in the job status dialog.

The second image is added to the CellArray with the same settings as the first

When the resampling is complete, click OK

View the First Set of Orthoimages / 26IKONOS Sensor Model Support

Note, this process could take several minutes, depending on the size of the images, the output orthoimage cell size, and your system resources.

View the First Set of Orthoimages

Now that you have two orthoimages of your IKONOS data, you can examine them in a Viewer.

1. On the ERDAS IMAGINE icon bar, click the Viewer icon.

If necessary, you may choose either the Classic Viewer and the Geospatial Light Table.


3. Click the Recent button and select the first orthoimage.

4. Click OK in the List of Recent Files dialog.

5. In the File Selector, click the Raster Options tab and make sure that Clear Display is not selected.

6. Make sure that the Fit to Frame and Background Transparent checkboxes are selected.

7. Click OK.

8. Follow step 2. through step 7., selecting the second file for display in the Viewer.

The orthoimages display in the Viewer.

IKONOS Sensor Model Support View the First Set of Orthoimages / 27

Check the Registration You can use the Swipe utility to see how accurately the images were orthorectified using only the information contained in the RPC file. Then you can compare this output with the results you get when you orthorectify the images using GCPs.

1. From the Utility menu in the Viewer, select Swipe.

The Viewer Swipe dialog opens.

2. Click the Zoom In icon , and click in the Viewer multiple times

until you can see an area of sufficient detail.

3. In the Swipe dialog, move the slider bar to the left and right to see how well the images overlap in the Viewer.

Use the slider bar to adjust the display of the images in the Viewer

View the First Set of Orthoimages / 28IKONOS Sensor Model Support

4. When you are finished checking the registration, click Cancel in the Viewer Swipe dialog.

5. Close the Viewer.

Notice that each column of the LPS Project Manager CellArray (with the exception of the DTM column, which is a separate process) is green indicating that the process is complete.

Even though you have completed the process, you can still backtrack and repeat steps to improve the registration of the images in the block file. In the next series of steps, you are going to select GCPs and specify a reference DEM with which to improve the output orthoimages’ accuracy.

Road networks are a good place to check the geometric fidelity of the output images

The process is complete (with the exception of the DTM generation), indicatby the green cells in each of the columns

IKONOS Sensor Model Support Start the Point Measurement Tool / 29

Start the Point Measurement Tool

The Point Measurement tool is designed to collect GCPs and tie points that are common to two images so that the images can be correlated. In the case of IKONOS imagery, the RPC file that comes with the images contains valuable information that lessens the need to collect large numbers of control points.

In this portion of the tour guide, you can see how choosing GCPs and generating automatic tie points can considerably improve the results of your orthorectification.

1. In the LPS CellArray, click in the > cell corresponding to the first image in the block.

This ensures that the first image in the block appears in the Left View.

2. On the LPS toolbar, click to select the Point Measurement icon .

The Point Measurement tool opens, displaying the two IKONOS images in the block file.

Add Control Points You can select well-distributed control points on each of the images with which to improve the correlation between the IKONOS images. In the following steps, ground control point coordinates that have been provided by the data vendor are added to the reference CellArray.

You are going to add control points to the reference CellArray

Start the Point Measurement Tool / 30IKONOS Sensor Model Support

1. In the Point Measurement tool, click the Add button.

A new Point # is added to the reference CellArray at the bottom of the Point Measurement tool.

2. Click in the Description cell and type SD-GCP7.

3. Click the Type cell and select Full.

4. Click the Usage cell and select Control.

5. Using the following table, input the X, Y, and Z Reference values into the reference CellArray.

You can optionally change the format of the columns to increase the number of places past the decimal. Right click in the column heading, choose Format, and enter the Custom Format (for example, 0.000000). Click Apply, then Close to apply the new format. This format information is not saved when you exit LPS Project Manager.

NOTE: Even if all numerals past the decimal do not display in the cell, LPS Project Manager uses all the coordinate information you supply.

6. Locate the points and place them in the two images using the Create

Point tool .

The following table gives coordinates of the points. These coordinates are placed in the file CellArray at the bottom right of the Point Measurement tool.

7. Click the Add button to add another point.



Table 1: SD-GCP7 Reference Coordinates

Point ID X Reference Y Reference Z Reference

SD-GCP7 -117.148912 32.835735 80.31

Table 2: SD-GCP7 File Coordinates

GCP Image X File Y File

SD-GCP7 1 4412.078 605.672

2 4409.696 605.957

IKONOS Sensor Model Support Start the Point Measurement Tool / 31




Point tool . The following table gives file coordinates.







Point tool . The following table gives coordinates.




SD-GCP10 -117.085834 32.837056 132.82



SD-GCP10 1 4747.460 2039.984

2 4737.814 2040.044



SD-GCP90 -117.163992 32.749788 53.42



SD-GCP90 1 2005.597 738.606

2 2006.565 738.609

Start the Point Measurement Tool / 32IKONOS Sensor Model Support






Point tool . The following table gives coordinates.

25. Click Save in the Point Measurement tool.

Your Point Measurement tool should look similar to the following.



SD-GCP110 -117.142110 32.692361 -31.54



SD-GCP110 1 542.547 1568.697

2 556.201 1568.880

IKONOS Sensor Model Support Start Auto Tie / 33

Start Auto Tie LPS Project Manager can automatically select tie points in your block file with the help of the control points you just selected. Tie points can also improve your final orthoimages.

1. In the Point Measurement tool, click the Auto Tie Properties icon

.

The Automatic Tie Point Generation Properties dialog opens on the General tab.

In this case, the default settings in the dialog are appropriate.

2. Click Run in the dialog.

Reference coordinates are Corresponding file coordinaisted in this CellArray display here

Click Run to begin Auto Tie

Refine the Model with Polynomials / 34IKONOS Sensor Model Support

When the process is complete, the tie points are appended to the bottom of the reference CellArray in the Point Measurement tool.

3. Click in the > column of one of the points to see its location in both images.

If you wish, you can view each of the automatically generated tie points and deactivate the ones that are at the edges of the image by clicking in the Active column to remove the X.

Refine the Model with Polynomials

With IKONOS data, you can refine the sensor model with polynomials, which are contained in the RPC file you specified in the Frame Editor dialog. Using these coefficients along with the GCPs creates a more accurate orthoimage.

1. Click the Triangulation Properties icon in the Point

Measurement tool.

The Rational Function Refinement dialog opens.

Pixel coordinates for the tie points are located in the file CellArray

IKONOS Sensor Model Support Refine the Model with Polynomials / 35

2. Make sure the Refinement with Polynomials checkbox is checked.

By using this option, you apply polynomial corrections to the original rational function model. This option corrects remaining error and refines the mathematical solution.

3. Click in the Polynomial Order field and type 1, or use the increment nudgers.

An order of 0 would result in a simple shift to both image x and y coordinates. A 1st order, as used in this example, applies an affine transformation.

4. In the Rational Function Refinement dialog, click the Run button.

The Refinement Summary dialog opens.

If you wish, you can click the Report button to see a more detailed refinement report.

5. Click Accept in the Refinement Summary dialog.

This saves the refinement information to the block file.

6. Click Accept in the Rational Function Refinement dialog.

The X Reference, Y Reference, and Z Reference cells corresponding to the Tie points update.

7. Click Save in the Point Measurement tool.

Click the checkbox to refine with polynomials—this improves the solution

The total error isreported here


8. Click Close in the Point Measurement tool.


Now, you can ortho resample the imagery.

1. Click in the Ortho column to open the Ortho Resampling dialog, or

click the Ortho Resampling icon .

2. You are prompted as to whether or not you want to delete the orthoimage corresponding to the first image you created in the first part of this tour guide. Click No in the Attention dialog.

The Ortho Resampling dialog opens:

3. Click in the Active Area field and type 90.0, or use the increment nudgers to the right of the field.

4. Click in the Output File Name section and type a new name for the output orthoimage.

5. Click the DTM Source dropdown list and select DEM.

6. Click the dropdown list next to DEM File Name and select Find DEM.

NOTE: You must supply your own DEM.

Images to be resampled display in the CellArray

Set the active area to use a percentage of theoriginal imageSelect a DEM

covering the area

Output cell sizes are measured in degrees


The DEM you select must overlap the input images by at least 30% in order to be used in orthoresampling.

7. Select the DEM and click OK in the File Selector.

8. Click in the Output Cell Sizes fields and enter .00004 in both the X and Y fields.

NOTE: These cell sizes are measured in degrees, not meters.

9. Click the Advanced tab in the Ortho Resampling dialog.

10. Click the checkbox next to Ignore Value, and maintain the value of 0.

Now that you have the parameters set, you can add the other IKONOS image, and it inherits those parameters.

11. Click the Add button at the bottom of the dialog.

12. You are prompted as to whether or not you want to delete the orthoimage corresponding to the second image you created in the first part of this tour guide. Click No in the Attention dialogs.

The Add Single Output dialog opens.

13. Click the Input File Name dropdown list to select the second image in the block file.

14. Give the output image a name.

15. Make sure that the checkbox next to Use Current Cell Sizes is selected.

16. Click OK in the dialog to transfer the information back to the CellArray of the Ortho Resampling dialog.

The second image in the block file is added to the Ortho Resampling CellArray with the same parameters (for example, cell size and constant elevation value) as the first image in the block file.

17. Click OK in the Ortho Resampling dialog to start the ortho resampling process.

A Job Status dialog opens to display the progress of the ortho resampling.

18. When the process is complete, click OK in the job status dialog.

Note, this process could take several minutes, depending on the size of the images, the output orthoimage cell size, and your system resources.

Compare the Results / 38IKONOS Sensor Model Support

Compare the Results

Now you can view the two sets of orthoimages in Viewers and compare the results of ortho resampling both without and with GCPs and tie points.

1. On the ERDAS IMAGINE icon bar, select the Viewer icon.


3. Click the Recent button and select the first orthoimage.


5. In the File Selector, click the Raster Options tab and make sure that Clear Display is not selected.

6. Make sure that the Fit to Frame checkbox is selected.

7. Make sure that the Background Transparent checkbox is selected.

8. Click OK.

9. Follow step 2. through step 7., and select the second file.

The orthoimages display in the Viewer.

IKONOS Sensor Model Support Compare the Results / 39

Check the Registration You can use the Swipe utility to see how accurately the images were orthorectified using only the information contained in the RPC file. Then you can compare this output with the results you get when you orthorectify the images using GCPs.

1. From the Utility menu in the Viewer, select Swipe.

The Viewer Swipe dialog opens.

2. Click the Zoom In icon , and click in the image multiple times

until you can see an area of sufficient detail in the Viewer.

3. In the Swipe dialog, move the slider bar to the left and right to see how well the images overlap in the Viewer.

Use the slider bar to adjust the display of the images in the Viewer

Check Results in LPS / 40IKONOS Sensor Model Support

4. Compare the registration with the first set of orthoimages you created.

5. When you are finished checking the registration, click Cancel in the Viewer Swipe dialog.

6. Select File | Save in the LPS Project Manager.

Check Results in LPS

You can see a graphical representation of the orthos you created in the LPS Project Overview window.

1. In the Block Tree View on the left-hand side of the dialog, click the plus sign next to Orthos to expand the list.

Road networks are a good place to check the overlap of the images

Click the plus signto expand the list

IKONOS Sensor Model Support Check Results in LPS / 41

2. Resize the Block Tree View as necessary to see as much of the complete file names as you like.

3. To view a specific ortho in the Project Graphic Status window, select it either in the Orthos list or in the CellArray at the bottom of the LPS Project Manager.

Check Results in LPS / 42IKONOS Sensor Model Support

4. With the Selector tool , click on one of the Squares (Tie Points)

or Triangles (Control Points) displayed in the image to see the Point Data for that point.

5. Once you have finished reviewing the data, click the Dismiss button to close the Point Data dialog.

IKONOS Sensor Model Support Next / 43

6. Click the Save icon on the LPS toolbar to save the changes to

your block file.

7. Close LPS by selecting File | Exit.

8. Close the Viewers by selecting File | Close.

9. If you wish, close ERDAS IMAGINE by selecting Session | Exit IMAGINE.

Conclusions While the RPC file associated with IKONOS imagery can provide valuable information regarding the interior and exterior orientation of an image to produce accurate orthoimages, using a few GCPs and tie points can further improve the quality of the output orthoimages.

Next Next, you can learn how to create DTMs from your IKONOS data using LPS ATE.

Next / 44IKONOS Sensor Model Support

Create/Open a Block File / 45IKONOS Sensor Model Support

LPS Automatic Terrain Extraction IKONOS Support

Introduction In this section of the tour guide, you can see how to use LPS ATE to extract DTMs from IKONOS imagery.



• Create/open a block file.

• Set DTM extraction properties.

• Check advanced extraction properties.

• Generate the DTM of the IKONOS images.

• Use the DTM in orthorectification of the images (optional).

Create/Open a Block File

You must supply your own data in order to execute the steps in this tour guide. However, the steps are applicable to any IKONOS data.

The IKONOS data in this example is of San Diego, California, USA.

This tour guide assumes that you already have a block file that you have created with LPS Project Manager. If you need instructions on how to create a block file using IKONOS data, see “LPS Project Manager IKONOS Support”.


2. Click the LPS icon on the icon panel.

The LPS Project Manager opens.

Create/Open a Block File / 46IKONOS Sensor Model Support

3. Click the Open icon at the top of the dialog.

A File Selector opens, from which you can select a pre-existing block file.

4. Navigate to the appropriate directory, select the block file, then click OK in the File Selector.

The LPS Project Manager updates to include the new block file information.

IKONOS Sensor Model Support Set DTM Extraction Properties / 47

Set DTM Extraction Properties

Now, set the properties for extraction of the DTM from the IKONOS data.

1. From the LPS toolbar, select the DTM Extraction icon , or select

Process | DTM Extraction.

The DTM Extraction dialog opens. It allows you to select the type of DTM you wish to create, as well as the parameters to apply during the extraction of the DTM.

All of the necessary parameters have already been defdirectly to DTM extractionyou can proceed

Select Advanced Properties / 48IKONOS Sensor Model Support

By default, the Output DTM Type is DEM.

2. In the Output Form section, click the radio button next to Single DTM Mosaic.

3. In the Output DTM File section, click the Open icon and

navigate to a directory where you have write permission.

By default, output images are placed in your Default Output Directory as specified in your IMAGINE Preferences.

4. Give the DEM a name, then click OK in the File Selector.

5. Change the DTM Cell Size in X and Y if you wish.

The use of this option removes erroneous data that may appear at the edges of the images. This eliminates the need to subset at the end of the DTM extraction process.

Select Advanced Properties

You can assign advanced properties to the images that are used in DTM extraction. You can also generate quality images as well as contour images as well as DTMs using LPS ATE.

1. Click the Advanced Properties button on the DTM Extraction dialog.

General Tab The DTM Extraction Properties dialog opens on the General tab. The General tab has information regarding the projection and units, which are inherited from the block file.

You also have the opportunity here to generate a Contour Map corresponding to the output DTM. You can select a contour interval that suits your application.

To check the accuracy of the output DTM, an option to create a DTM Point Status image. It has categories defining the accuracy of the DTM.

Output type is DEM by default

Choose the form and give the output a name

Trim the border to removeerroneous data

IKONOS Sensor Model Support Select Advanced Properties / 49

You also have the option to reduce the correlation area in the General tab. The reduction occurs before DTM processing and reduces the edges of the images by a specified percent. If you select 10%, for example, 5% is removed from each of the four sides of the output DTM.

2. Click the checkbox next to Create Contour Map.

The Contour Map is in Shape file format, and is designated with "_contour" appended to the file name.

3. In the Contour Interval field, change the value to 20.

4. Click the checkbox next to Create DTM Point Status Output Image.

The DTM Point Status image is in ERDAS IMAGINE .img format, and is designated with "_quality" appended to the file name.

Image Pair Tab The Image Pair tab is used to evaluate image pairs and determine which image pairs you want to use for automated DTM extraction. Only those image pairs that overlap by the specified overlap threshold are active.Click the Image Pair tab.

1. Click the Image Pair tab.

2. Click the View icon to open the views at the top of the dialog.

Create supplemental map and image by checking the checkboxes

Select Advanced Properties / 50IKONOS Sensor Model Support

Notice that there is only one image pair in the block file. It is designated Active, and the DEM will be generated from it.

Area Selection Tab The Area Selection tab is provided so that you can specify which geographic regions contained within an image pair are used for DTM extraction, or are not used for DTM extraction. You can create custom strategies applicable to particular regions to improve the accuracy of your output DTM.

1. Click the Area Selection tab.


Image pairs in theblock file arelisted here in theCellArray

IKONOS Sensor Model Support Select Advanced Properties / 51

Notice that the OverView displays the extent of the correlation area in red, and the default overlap in white. This helps you to digitize regions in the Area Selection tab for the purpose of applying specific strategies.

Accuracy Tab The Accuracy tab is provided so that you can define 3D reference information that is used to compute the accuracy of the output DTM. 3D reference information includes control, check, and tie points from the block file; an external DEM covering all or a portion of the image pair; and tie points you define.

1. Click the Accuracy tab.


3. Click the checkbox next to Use Block GCPs.

4. Click the checkbox next to Use Block Tie Points.

5. Click the checkbox next to Use External DEM.

6. Click the Open icon next to Use External DEM to open a File

Selector.

Tools for digitizingregions are here

Regions are listedin the CellArray asthey are created

This is theOverView

Generate the DTM / 52IKONOS Sensor Model Support

7. Navigate to the directly containing the DEM, select it, and click OK in the File Selector.

NOTE: You must supply your own DEM.

The Graphic Status Display of the Accuracy tab updates accordingly.

8. Click OK in the Accuracy tab.

You are returned to the DTM Extraction dialog.

Generate the DTM

1. Click Run in the DTM Extraction dialog to start the process.

A status bar appears at the bottom of the LPS ATE dialog tracking the progress of the DTM extraction.

When the extraction is complete, the DTM column in the LPS CellArray becomes green.

Options for computingaccuracy are here

Click a Row # to highlight that pointin the Graphic StatusDisplay

IKONOS Sensor Model Support View the DEM / 53

View the DEM

1. On the ERDAS IMAGINE icon bar, select the Viewer icon.

NOTE: You may be prompted to choose either the Classic Viewer or the Geospatial Light Table.


3. Click the Recent button and select the DEM you just created.


5. Click OK In the File Selector.

The DEM displays in the Viewer. You may need to fit the image to the window.

The DEM can now be used in other applications such as Stereo Analyst and IMAGINE VirtualGIS.

Check the Contour Map / 54IKONOS Sensor Model Support

6. Clear the Viewer by clicking the Remove Contents from Viewer icon

.

Check the Contour Map

1. In the open Viewer, click the Open icon to access a File

Selector.

2. Navigate to the directory in which you saved the Contour Map (the same directory as the output DEM).

3. Click the Files of type dropdown list and select Shapefile (*.shp).

4. Select the file (it has a “_contour” element), and click OK in the File Selector.

The Contour Map displays in the Viewer.

The Contour Map can be viewed in conjunction with the DTM Point Status image to evaluate the accuracy of the output DTM.

IKONOS Sensor Model Support Check the DTM Point Status Image / 55

Check the DTM Point Status Image

1. In the same Viewer, click the Open icon to access a File

Selector.

2. Navigate to the directory in which you saved the DTM Point Status image (the same directory as the output DEM).

3. Click the Files of type dropdown list and select IMAGINE Image (*.img).

4. Select the file (it has a “_quality” element), and

5. Click the Raster Options tab.

6. Make sure that Clear Display is not active.

7. Make sure that Fit to Frame is active.

8. Click OK in the File Selector.

The DTM Point Status image displays over the Contour Map in the Viewer.

Arrange Layers

1. From the View menu, select Arrange Layers.

2. Click, hold, and drag the raster layer, ikonos_dem_quality.img(:Layer_1), below the vector layer, Vector: ikonos_dem_contour.shp.

3. Click Apply in the Arrange Layers dialog.

Check the DTM Point Status Image / 56IKONOS Sensor Model Support

The Contour Map displays over the DTM Point Status image. By viewing the output files in this way, you can identify areas that may benefit from post-processing.

For information about post-processing DTMs generated by LPS ATE, see the Leica Photogrammetry Suite Project Manager User’s Guide and the Leica Photogrammetry Suite Automatic Terrain Extraction User’s Guide, which is located in the <IMAGINE_HOME>/help/hardcopy directory.

4. Click Close in the Arrange Layers dialog.

Check Attributes The DTM Point Status image has an attributes table that details the number of Excellent, Good, Fair, Isolated, and Suspicious points in the output DEM.

1. From the Raster menu, select Attributes to open the Raster Attribute Editor table.

2. Resize the table by dragging the corners and sides to see all of the information.

IKONOS Sensor Model Support Conclusions / 57

The number in the Histogram column corresponds to the number of pixels with the value of Background, Excellent, Good, Fair, Isolated, and Suspicious.

3. When you are finished looking at the Raster Attribute Editor, select File | Close.

4. Close the Viewer.


At this point, you might choose to ortho resample the images using the DEM you created. First, however, you should check the DEM and perform any necessary post-processing. If you want to perform this process, see “Ortho Resample the Images” for instructions.

Close the Project

1. Click File | Save in the LPS Project Manager.

2. Click File | Exit in the LPS Project Manager to close LPS.

3. Close ERDAS IMAGINE, if you wish, by selecting Session | Exit IMAGINE.

Conclusions As this chapter has shown, you can make highly accurate DTMs of your IKONOS data using LPS ATE. You can use these DTMs in other applications such as IMAGINE VirtualGIS and Stereo Analyst. Next, you can learn about the Stereo Analyst IKONOS functionality.

Conclusions / 58IKONOS Sensor Model Support

Start Stereo Analyst / 59IKONOS Sensor Model Support

Stereo Analyst IKONOS Support

Introduction In this section of the tour guide, you can see how to use Stereo Analyst to view and IKONOS images.



• Open a Stereo Analyst workspace.

• Select the metadata text file.

• View the IKONOS data in block file format.

Start Stereo Analyst

You must supply your own data in order to execute the steps in this tour guide. However, the steps are applicable to any IKONOS data.

The IKONOS data in this example is of San Diego, California, USA.

Start from ERDAS IMAGINE


2. Click the Stereo Analyst icon on the tool bar.

3. On the Stereo Analyst dialog, click to select Stereo Analyst...

An empty Stereo Analyst workspace opens.

Click this button

Load IKONOS Images / 60IKONOS Sensor Model Support

Load IKONOS Images

1. From the File menu of the empty Stereo Analyst workspace, select Open | Open an Image in Mono.

2. Click to select the *.tif file, then click OK in the file selector dialog.

That image loads in the Stereo Analyst Workspace.

3. Select File | Open | Add a Second Image for Stereo.

4. Click to select a second *.tif file, then click OK in the file selector dialog

Stereo Analyst reads the metadata.txt file and RPC files associated with the images listed in the metadata file. From those files, you can create a block (*.blk) file. It is that block file which is opened in the Stereo Analyst workspace.

Select the file to reate a block

IKONOS Sensor Model Support Use of the IKONOS Block File / 61

Use of the IKONOS Block File

This block file is like any other, and you can use it in Stereo Analyst to perform the following tasks:

• collect true, real-world, three-dimensional geographic information in one simple step, and to higher accuracies than when using raw imagery, geocorrected imagery, or orthophotos,

• use timesaving, automated feature collecting tools for collecting roads, buildings, and parcels,

• attribute features automatically with attribute tables (both spatial and nonspatial attribute information associated with a feature can be input during collection),

• collect and measure 3D information,

• collect X, Y, Z mass points and breaklines for triangulated irregular networks, and import and export in 3D, and

• directly output and immediately use your 3D Shape files in ERDAS IMAGINE and ESRI Arc products.

Conclusions / 62IKONOS Sensor Model Support

Conclusions As you have learned, opening an IKONOS block file in Stereo Analyst is an easy process. Once the block file is displayed in the workspace, you can use it like any other block file.

Index / 63IKONOS Sensor Model Support

IndexSymbols*.gms file 10

AAccuracy tab 51Add data to the block 16Advanced properties 48Area Selection tab 50Attributes 56Auto tie 33Automatic tie point generation properties 33

CContour Map 54Create Contour Map 49Create DTM Point Status image 49

DDialog

Rational Function Refinement 35Digital stereo model 1Digital terrain model 1DSM 1DTM 1DTM extraction properties 47DTM Point Status image 55

FFile format

*.gms 10Frame properties 21

GGCP 1General tab 48Geo-correction 4Geographic Lat/Lon 20Geometric correction tools 8Geometric model 5Ground control point 1

IIGM 1IKONOS model properties 6IKONOS Sensor Model 15Image geometric correction 4Image geometry model 1Image Pair tab 49

LLoad IKONOS images 60

MMetadata file 60Metadata files 1Model setup 15

PPoint Measurement tool 29Polynomial order 35Polynomial refinement 34Pyramid layers 18

RRational function refinement 34Rational Function Refinement dialog 35Rational polynomial coefficient 1Rational Polynomial Coefficients 19Refine model 34Refinement summary 35Resample 8RPC 1RPC file 19RPC file example 20RPC Files 7

SSet geometric model 5Single-frame orthorectification 4Start Stereo Analyst 59

TTriangulation properties 34

VViewer swipe 27, 39

IKONOS Sensor Model Support Index / 64

ikonos sensor model support tour guide

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