1 reply to this topic

[greg585]

I'm currently using the nearmaps hypertiles program to download aerial photos for use with lots of maps. Think its pretty much the best to use in Australia.

The downloaded tiles come in JPW format which are very large and cannot be widely used with GIS viewer programs.

Does anyone know how i can convert the JPW to something more widely recognised?

Have access to ArcINFO

Thanks,

Greg

[KlausDE]

The JPW file is very small and only contains pixel size and offset of the lower left coordinate, sometimes rotation parameters. You reference the corrosponding (=same basename.JPG) JPG and the GIS automatically searches for a JPW file for this information. If you feel the need to convert the image you could use GeoTIFF which doesn't need an extra worldfile or you use ECW or other formats that in adition to the local offsets contain imformation about the projection, too. They all usually have a larger filesize than JPG+JPW.