Frequently asked Questions
Q When I open an ECW image for the first time in MapInfo Professional, it doesn’t display. What should I do?

A The most common reason why an ECW image wont display is because the Zoom is outside the default settings for Min and Max Zoom. This tends to happen because ECW images typically have much larger width and height than other images. You can change this as shown below. Uncheck ‘Display within Zoom Range’ box.’

Map -> Layer Control -> Display -> Display within Zoom Range

Q Sometimes when I am displaying a URL image, across the Internet, I zoom in, but I don’t see the full resolution of the image?

A This is because you have a slow communications link to the Image Web Server. ECW for MapInfo waits for a reasonable amount of time, and then displays whatever imagery it has received from the server.

If you are connected to the Image Web Server across a LAN or if you have a reasonably fast Internet connection, you should always see the full resolution of ECW images.

If you have a slow connection, then repeatedly press Control D, or Window -> Redraw Window, until the resolution improves. When the draw returns immediately, then you have reached the maximum resolution.

Q What is a .url file and why do I need to use a .url file to access ECW images on an Image Web server?

A A .url file is just a disk file containing the address of a remote .ecw file. It is required because the standard MapInfo file chooser can’t handle a URL type address. You need to create a .url file (manually or via MapImagery) in order to view a remote ECW image on an Image Web Server

For example the file c:\giddata\spotcalif.url contains the following address:


Q Where can I find some example .ECW images?

A The EarthEtc Web site  is a good source of example Image Web Server .ECW images. Alternatively ask your data vendor if they can supply imagery in .ECW format.

Another useful site which contains ECW sample data from various sources is the MapInfo section of the eMapSite Web site