Mapping amusing places

Tuesday, 30 October, 2007

Thanks to my brother for this link to the Amusing Places website. Having spent many hours looking at OS maps (for example), this is an appropriate use of a Gazetteer. One wonders if the OS have already “flagged” up certain places in the UK…..

Big TIFF is out.

Sunday, 28 October, 2007

BigTIFF appears to be coming close to an official release. TIFF has been a popular format within geospatial circles for a while because its an open format (although Adobe owns the specification) and there is the open source libtiff library used for reading/writing TIFFs. It’s also incredibly extensible and has proved the test of time when it comes to image processing. . The problem for the geospatial industry?? File size is currently restricted to 4Gb. This might have seemed gargantuan 5 years ago but there are now many libraries of images which are easily bigger than this. So the BigTIFF project was formed which garnered industry financing to support the extension of libtiff to break the 4Gb barrier. ESRI and Leica are amongst the industry support and its a cheap way for them to get an extended TIFF format.

So where can you use BigTIFF? Well as far as I’m aware Ossim is the first to support it (at least in the geospatial arena). So if you haven’t tried Ossim, now’s a good time.

Concatenating in Windows

Wednesday, 3 October, 2007

I was recently sent some LiDAR data x,y,z triples (i.e. x coordinate, y coordinate and elevation); actually, it also had intensity so quadruples I guess. Anyway, the data were extracted for a 1km2 area from multiple flight lines which meant I had multiple x,y,z values. Before importing these as a LiDAR LAS file I wanted to concatenate them. Easy to do in Linux but I couldn’t remember how to do it in Windows. A quick Google later led me to this useful article over at Lockergnome. And for those too lazy to click, this for loop will do the work for you:

for %f in (*.log) do type “%f” >> aggregate.txt