Duplicate data in map files

[John P]

A while ago I noticed that a place name on a map was wrong, and I decided to fix it up using GPSMapEdit. When I did that, the corrected name appeared overlaid with the wrong name--which made me think it had been in there twice to begin with. I exported the file from GPSMapEdit in Polish format, which is a human-readable form, and sure enough, there were identical features, now with two different names. Back in GPSMapEdit I used the command "Remove Object Duplicates", and it found plenty of them.

The file which covers my home in Massachusetts is a good example (94537047.IMG). It has a size of 9.25MB, but if you import it to GPSMapEdit, eliminate the duplicates (68470 of them!) export it and re-compile to an IMG file, it shrinks to 7.51MB. But given how long compilation takes with cGPSmapper, I'm not going to do it for very many files.

I don't want to seem like someone who's ungrateful for free stuff! Having these maps available is what really makes owning a mapping GPS receiver worthwhile, but it seems as though the files do have this excess data. I wonder if the people who create the map files are aware of it.

[jbcnbama]

When you saved the img file as an mp and exported again as an img, did you have any trouble loading the map to your GPSr?  I did something similar, I think, but now I can't download the overall SEUSA map anymore.  If I put the original img file back, I can download with no problem.

[-Oz-]

jbcnbama; did you remake the preview images (probably what you need to do)...

[jbcnbama]

I didn't remake the preview files since my changes automatically showed  up in mapsource after I dropped the modified file into the directory.  I'll try to re-process the preview files with toolkit and let you know what happens.  If that works, it's still saves a ton of time building from scratch.  Thanks.