ECW ArcIMS® Connector and ER Mapper Raster Plug-in for ArcGIS® 8.x-9.x

Introduction

The ArcGIS 8.x-9.x Raster Plug-in allows greater productivity in the ArcGIS environment by adding support for ECW, URL, ALG and ERS image formats. It also includes the ECW compressor utility so you can now serve ECW images using your ArcGIS server. Join our community forums at: http://forum.ermapper.com/

Version

2.0

Supported Raster Formats

ECW, URL (Remote ECW), ALG and ERS

ECW Compressor Limitations

500MB Uncompressed Input Raster Size (larger imagery will be sub-sampled to 500MB)
Current Supported Input formats (ERS, ALG, HDR, BMP, DAT, DOQ, ECW, TIF and JPG).

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Installing the ArcGIS® plug-in

Installation Options

Double-click on the plug-in .exe file to begin the installation. You will be prompted to choose from the following options:

Option

Description

Destination Folder

Choose a folder where you would like the installation to take place. The majority of the program files will be placed here including documentation, sample data and ER Mapper runtime files. The default value is in program files i.e. C:\Program Files\Earth Resource Mapping\ArcGIS Plug-in with ECW Compressor

Setup Type

Choose between three setup types: Compact, Custom or Typical.

Compact setup will only install the ArcGIS plug-in. This

Custom setup is the default option and allows you to select the components to install. All of the components are selected by default, taking advantage of all the plug-in features.

Typical setup will install the ArcGIS plug-in and ECW compressor without the sample ECW files.

Note: you can reinstall the software to modify, repair or remove components.

Verifying Successful Installation

After installation, start ArcGIS and bring up the Options window by selecting the Tools > Options menu. Select the Raster tab. Under Raster Format Browsing, check that .ecw, .url, .alg, and .ers are listed as a valid raster formats. In ArcGIS 9.x, click on the File Formats button to display the same list.

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Adding/Viewing ECW and ER Mapper Images in a Project

ECW and ER Mapper images can be added to your project like any other raster format that is included with ArcGIS. (Except for remote ECW images. These will be described in another section.)

Within ArcMap®

View tutorial [ 200KB | 0:33min ] Tutorial will open in a new window

  1. Select Add Data… under the File menu or click on the Add Data… button to bring up the Add Data dialog shown below.
  2. Select an ECW, ERS or ALG raster dataset in the list and click on the Add button.

Within ArcCatalog®

View tutorial [ 181KB | 0:27min ] Tutorial will open in a new window

  1. Select the ECW, ERS or ALG raster dataset from the category tree and click the preview tab of the geography window.

ECW Example Imagery

If you chose a custom installation and selected the example ECW images, then you can perform the above steps to check that everything is OK.

Using the ECW and ER Mapper Toolbar

The ECW and ER Mapper toolbar allow easy access to the Connector information and features.

Displaying/Enabling the Toolbar

The toolbar should automatically be displayed after installation. If not, the toolbar can be displayed by enabling it under the Customize dialog. Bring up the customize dialog from Tools > Customize. Select ECW and ER Mapper in the Toolbars tab. Click on Close to finish.

Description of Toolbar Functions

Index

Functions

Description

1

Add Remote ECW

This function brings up the Add Remote ECW dialog where you can specify the location of a remote ECW file. If the remote ECW URL is valid it will be added to the project. Note that this command is only available in ArcMap.

2

Launch ECW Compressor

This function brings up the ECW Compressor application. You can continue working with your project while compression is in progress. This command is only available if the ECW Compressor is installed.

3

Refresh

This function is used to refresh the view window in ArcCatalog and ArcMap. The refresh command might be needed when working with remote ECW images over slow network connections. The refresh is immediate.

4

Options

This function brings up the ECW and ER Mapper Raster Options dialog. You can specify the reading techniques and remote ECW options used by the plug-in.

5

Help

This function brings up this help documentation in the default html browser.

6

About

This function brings up the About ECW and ER Mapper Raster Support dialog. It provides information about the plug-in such as version and links to the release notes and to our websites.

Add Remote ECW (ArcMap® Only)

This window allows the user to enter the URL address of a remote ECW file and add it to an ArcGIS project.

To add the remote ECW image to project, first type in the URL address in the Address field at the bottom of the window and then click Add. If the URL is valid, it will be added to the project. Additional URLs can be added one after another. To view the most recent URLs, click on the down arrow to the right of the Address field. When typing the address, the closest match in the recent URLs will be found and the entry will be auto-completed.

To obtain the image properties and preview of the current URL in the Address field, click Get Properties and Preview button near the top right hand corner of the window. Note that you can zoom and pan by holding the left (and right) mouse button down while the cursor is over the preview window.

You can monitor the status message on the right hand side of the window to see what task is being processed or the status of the URL.

To close the dialog just click on the Close button at the top right corner of the window.

To check for existing URLs that have been added or included with the installation, click the Browse for URLs button:

This brings up the following window:

To provide URL support in ArcGIS, a local file with a .url extension is required to store the actual URL. This window lists all the URLs that are located in the directory currently assigned to store the URLs (see options). To look in another directory just click the button with the folder icon. This is useful to find URLs that you have entered previously or to share URLs over a mapped network drive.

Double click on or select and click on OK to add it to the address field of the Add Remote ECW Image dialog. This can now be added to the project or you can view the properties and preview the image.

Options

Click on the Options button to change the settings of the plug-in. Settings can be changed to optimize performance.

The current options can be divided into two areas: the raster reading technique and remote ECW imagery options. The dialog is shown below with default options. Index numbers have been added to the screen shot to help with the descriptions.

These options and buttons are described below:

Index

Option/Button

Description

Default Value

1

Force Block Reads

If this option is selected, instead of reading a group of blocks, each individual block is read (fixed size). This offers a reading technique that will be slower but may be more reliable or work better in some cases. This option will also display the raster as it reads the blocks (before SP1).

UNCHECKED

2

Display Performance (block size adjustment)

This changes the block size used when reading. This can make viewing, printing or saving faster, particularly when viewing a sub-section of a large image. If the view is not too large, the plug-in will read the blocks in groups. In this case, the smaller the block size, the more efficient is the raster request and hence it is displayed faster.

2 (MIDDLE)

3

Directory for .url files

When adding a remote ECW image to ArcMap®, local .url files are created which contain the location of the ECW. These files are stored in this directory and can be added to project like any other raster format.

<Plug-in Install Directory>\ArcGIS Plug-in\URLs

4

Display Progress Window

If viewing remote ECW over a slow network connection, the view may take a significant time to download. If this is the case and this option is selected, a progress dialog will be displayed.

CHECKED

5

Draft Quality Output

If viewing remote ECW over a slow network connection, the view may take a significant time to download. If this option is selected and the zoom level is greater than 1:1, the plug-in will sub-sample the data by a factor of 2. This means that the data can be displayed faster (potentially 4x) when roaming and zooming and then display at normal quality when zoomed in to 1:1.

UNCHECKED

6

Default

Sets all options to default, options are not saved, and the dialog is left open

-

7

OK

Save options and close the dialog

-

8

Cancel

Do not save any changes to the options and close the dialog

-

9

Apply

Save options but leave the dialog open

-

About Window

Click on the About button to view the following information about the plug-in:

Click on OK to close the window.

Accessing Individual Commands

If you need to access individual commands included with the plug-in to customize ArcGIS, bring up the Customize dialog by going to Tools > Customize menu, then click on the Commands tab. Under Categories, select “Earth Resource Mapping” and the available commands should appear in the Commands pane on the right hand side. You can assign shortcut keys to each command by clicking on the Keyboard… button.

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Adding/Viewing Remote ECW Images to a Project

Within ArcMap®

View tutorial [ 160KB | 0:20min ] Tutorial will open in a new window

Click the Add Remote ECW… command button on the ECW and ER Mapper toolbar. Please refer to the earlier section “Using the ECW and ER Mapper Toolbar”.

Within ArcCatalog®

View tutorial [ 253KB | 0:49min ] Tutorial will open in a new window

Follow the steps in the earlier section “Adding/Viewing ECW and ER Mapper Images to Project”. The difference in ArcCatalog is that the file you choose has a .url extension. To find the location of the URLs, check the “Directory for .url Files” option (see section “Using ECW and ER Mapper Toolbar” > “Options”).

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Accessing the Free ECW Compressor

The ECW Compressor included with the plug-in has an input size limit of 500MB and runs as a separate executable. It offers the following advantages:

If you want to use the ECW compressor in ArcGIS, it must be installed on your machine. If you have not installed it already, you can re-run the installation, choose Modify, and select the ECW Compressor as part of the install.

To access the ECW Compressor in ArcGIS, use the Launch ECW Compressor button on the toolbar (see section “Description of Toolbar Functions”)

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General Notes on Usage

The compressor is straightforward to use, but if you need help just click on the Help button.

Within ArcCatalog®

When using ArcCatalog, you can right click the raster dataset to compress, and then select Export > Raster to ECW… from the list. If the input raster dataset is recognized as valid by the compressor, the input and output filenames will be automatically filled in. All that needs to be done is to click on Apply to proceed with the compression.

Within ArcToolbox® (ArcGIS® 8.x Only)

To start the ECW compressor from within ArcToolbox, double click on the Raster to ECW tool. This tool is located under Conversion Tools > Export from Raster. You can also navigate to it from the Tools > Find menu.

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Useful Tips and Usage Information

General

Make sure you have installed the latest Service Packs and necessary patches for ArcGIS to provide optimal performance. These can be found at http://support.esri.com

Using ArcGIS to mosaic numerous ECW or ER Mapper images is slower than displaying a single larger ECW image. For best results, use ER Mapper to create your large mosaic (tile and color balance), save the result to an ECW file and then use it in ArcGIS.

View the ECW or ER Mapper image at 1:1 zoom (dataset resolution) for faster display, as no sub-sampling is required by ArcGIS. The ArcGIS command Zoom to Raster Resolution is useful in zooming to 1:1.

The larger the view window, the longer is the time required to display the ECW or ER Mapper image.

Overview and Magnifier Windows

As ECW displays large raster images in ArcGIS swiftly, the Window Overview and Magnifier utilities included with ArcMap are useful in working with these large images. Please refer to the help documentation supplied with ArcMap for usage.

Raster Options in ArcMap®

In ArcMap you can change the display properties of the raster layer to improve the display times and appearance of the ECW or ER Mapper images. Two settings of interest are “re-sample” and “quality”. Setting the re-sampling to Bilinear will improve the visual appearance, and changing the Display Quality will also influence the display times. This has the same effect as the smoothing option in ER Mapper.

To access the above dialog, follow these steps:

  1. Add the ER Mapper file into ArcGIS
  2. Right click on the layer name (under the Layers heading in the left hand pane)
  3. Select Properties… from the drop down menu
  4. The Layer Properties dialog will appear as shown above. Set the options to the match the above screenshot.

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Known Problems/Issues

1. When adding an ECW or ER Mapper image I receive a warning that “One or more layers is missing spatial reference information…”

The coordinate space (projection/datum) strings set by the plug-in are not understood by ArcGIS and appear as “unknown”. ArcGIS’s native ERS support is also limited to certain formats, resulting in the same problem. The workaround is to edit the projection/datum information using ArcGIS. The steps below describe the workaround:

  1. Find and delete the corresponding .aux file for the image e.g. image.aux for image.ecw
  2. Bring up the properties window in ArcCatalog by right clicking on the ECW / ER Mapper file
  3. Click the Spatial Reference tab and then click on Edit
  4. Click on Select and choose the appropriate pre-defined coordinate system that matches the original ECW / ER Mapper file projection/datum.
  5. Close ArcCatalog, start ArcMap and then load the ECW / ER Mapper file
  6. Bring up the layer properties by right clicking on the ECW file, and select the source tab
  7. Scroll down to the Data Source section and you will see the projection/datum information preserved

Support for ER Mapper projection/datum strings in ArcGIS will be investigated for future versions.

2. When viewing remote ECW images over a slow network connection, distortion appears in the top left corner of the image

This can be fixed by clicking the refresh button on the toolbar.

Changing to block reads (Force Block Read option) may also help.

3. The progress window remains after image is loaded

Change the view, use the refresh button or go back to previous extents. If the window still remains, try selecting the blank window tab in the Windows task bar and press Alt+F4 to close the window. The progress window can be turned off in the options.

4. When zooming close into large raster datasets, the image appears black

This is a known problem with ArcGIS 8.x. Download and install the following patch by ERSI “ArcGIS Desktop 8.3 RPF and Memory Management for Large Raster Data Patch” to fix the problem.

5. When viewing large ECW images in ArcMap®, there may be a long pause between roam and zooms or getting properties

This is the result of ArcMap attempting to calculate statistics, and a status message appears at the lower left corner of the window. Hold ESC key to cancel the statistics calculation and continue.

6. When attempting to view ERS files, you receive message boxes indicating that the plug-in could not determine the band number

Close ArcGIS, delete the .aux files that are associated with the ERS files and try again.

7. All ER Mapper datasets appear as 8-bit in ArcGIS®

The plug-in converts all ER Mapper files to 8-bit data depth upon loading, restricting stretch values of non 8-bit files to 0-255. This problem is being investigated.

8. Multi-band ER Mapper rasters appear as 3 band images in ArcGIS®, and specified band names of all layers are not displayed

The plug-in seems to be displaying ER Mapper rasters with a maximum of three bands, even though they may have more. It seems that the specified band names of ERS files are also ignored i.e. they appear as the default “Band 1”, “Band 2” and “Band 3”, instead of the names indicated in the ERS file. This problem is being investigated.

9. ArcGIS® displays some ER Mapper RGB datasets as grayscale

This problem is rare and occurs with few files, mainly those with WGS84/Geodetic as the Datum/Projection. The problem is being investigated.

10. Certain raster formats are missing or cannot be loaded by ArcGIS®

ER Mapper ALG and ERS install option causes missing raster formats in ArcGIS for certain users. After installing the plug-in, some users may experience certain raster formats are missing or cannot be loaded by ArcGIS. Such formats might be TIFF, JPG, etc. This unresolved problem is with ER Mapper ERS and ALG support (custom install option) and the regeneration of the raster settings. The problem is currently being investigated by ESRI. To check to see which formats are missing, launch ArcGIS and use the ToolsàOptions menu and click on the raster tab and see what is missing in the Raster Format Browsing list (or click the File Formats button in ArcGIS 9.x). A possible workaround is to run the install again (uninstall) and click on the modify option and then uncheck the ER Mapper ALG and ERS install option.

11. ER Mapper images display at poor resolution and appear pixilated and blocky

ER Mapper has an option to turn smoothing on, thereby removing the pixilated appearance of an image. This same feature is available in ArcGIS. Refer to the above section “Raster Options in ArcMap®”.

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Support and Reporting Problems

Use the information in this section to report any defects you may encounter whilst using the plug-in.

Read the available documentation to see if your problem is addressed. Refer to the section above on “Known Problems/Issues”.

If you still cannot resolve your problem, it is always worth checking on our website to see if similar problems have been mentioned in the Knowledge Base for your product. Alternatively, there might be a newer version of the plug-in available in the website product download section. Download this and use it to see if it solves your problem.

If the problem persists…

For Beta releases, visit the Beta Feedback page to submit a query.

For public releases, please contact the closest Earth Resource Mapping regional office for help. Email is the preferred method of correspondence and assures a quick response.

The subject field should be succinct, but informative as it will assist the support staff to quickly decide who can best answer your problem. Example:

Please remember that your question maybe first time we see your problem. The more you can tell us, the less likely it is that we will have to ask you for more details and the quicker we will be able to provide you with an answer. Details that should be included:

  1. Product name and version number e.g. ArcGIS 8.x-9.x ECW plug-in v2.0 RELEASE
  2. Version of software that plug-in is installed into, including patches e.g. ArcGIS 8.3 Service Pack 3
  3. Is the plug-in installed in the default directory? If not, where?
  4. Operating system e.g. Windows 2000 Service Pack 4
  5. System Specifications i.e. processor, CPU speed, RAM
  6. Summary of the problem
  7. Exact steps to reproduce the problem
  8. Sample data if applicable - include screen shots where useful e.g. error pop-ups, relevant images, dialogs with numerous options (like print settings), etc.
  9. Things you have tried yourself to fix or further investigate the problem

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