Archive for the ‘Nearby’ Category

Towards a standard Geotag Icon?

Sunday, March 2nd, 2008

Geotag DemoJust spotted a proposal for a standard icon to represent geotagged content, the homepage is at, can’t say a big fan of the icon itself, but the idea is great.

<OT>Was sort of involved in trying to find a standard icon for GeoRSS (in fact they use my icon as the favicon ;) ), but not sure (in hindsight!) if that a good idea, really it just saying this is a geotagged feed, which really shouldn’t mean much different to the end user than the standard feed icon. If their feed reader is geoenabled – great, if not tough, although it can help people specifically looking for geo-content.</OT>

Anyway to try the waters, have enabled it for geotagged content on this blog, see the PhotoSpot category for example :)


Where in the world are people looking? part 2

Saturday, March 1st, 2008

Following part 1 yesterday, have now plotted some maps per individual service.

Flash Earth Layer


  1. Google Earth does request a link for the initial view on startup – that point in the Atlantic.
  2. I guess North American installs have two slightly different default placemarks; has it changed, or maybe Canada gets a different one?
  3. But that doesnt explain the lines from there – people must have their links set to periodically refresh?
  4. Germany likes FlashEarth (or rather people like looking at Germany with FlashEarth link enabled)
  5. Many people leave the links open even when not in use – e.g. the British Isles links show worldwide usage, notably over Russia.
  6. MGRS notably has high usage in two areas.
  7. The Far east likes to know what direction they facing.

Update: In a total forehead slapping momont realised these unprojected whole world images, are exactly what is used in GroundOverlays, so the the pages now include links to view the higher resolution images directly in Google Earth, duh!

Example: View In Google Earth (don’t forget to try adjusting the tranparency slider!) [Update, to fix broken link, sorry!]

Where in the world are people looking? part 1

Friday, February 29th, 2008

As some may know this site serves a number of Network Links for Google Earth, for a long time I have thought it would be fun to map the data from that, but finally got round to trying it. This is still work in progress, so the current images are very much easly tests, but shows promise, hopefully can make some better visualizations – maybe even as KMZ :)

‘Lookat’ point v1: (click for 145k version)

View In Google Earth (don’t forget to try adjusting the tranparency slider!)

Shows some interesting patterns, there are a number of lines on the map, and definitily appears to be flight lines, I suspect this is from people leaving tours on loop, and a fudging a networklink to refresh periodically. Not sure how else to explain such repeatable loops – can a large number of visitors really be all following the same route? I’ll investigate this more in follow up map(s).

But WHAT is that point in the middle of the Atlantic?

Update: this is from about 900k hits from aug-nov ’07 – still processing the rest of the data!

Update 2: More maps here, all maps seem to to show the same overall pattern which is slightly puzzling, eg the IPs graph suggests that many users are following these flight lines.

When service users go bad?

Friday, February 29th, 2008

This is probably a purely a rhetorical question, and a means to vent. As background, I have just noticed a single user use a very disportionate number of requests against one of the Google Earth Grid Layers (MGRS), it look’s like they set it to refresh every 10 seconds, and for a while did browse around the globe, after that it stuck on one view and just happily refreshed away for 20 hours.

So what is the response to this type of thing (and I have no idea of the identity of users)?

  1. Blacklist at firewall level – effectively cutting them off from using nearby ever again.
  2. Blacklist them from that feature permanently
  3. Impose a temporally ban
  4. Add a throttling to the service for everyone, such as a quota or rate limiting – difficult to get the sweat spot
  5. Google Earth offers <maxSessionLength> which could be used to curtail the long term effect, but this would have a minor effect on legitimate users
  6. similar to last but only start adding it once they trigger some limit

So far (and only in a handful of cases) have done either 1 or 2. In the example that has triggered this post have done 1. but might change it to 3.

(the api and coordinate converter have their own dynamic limit, essentially 4. )

Geohash converter; API limit upped

Thursday, February 28th, 2008

Recently was released; the premise: short easy links that encode a location. The website offers instant conversion, but as the algorithm is Public Domain, Lordelph was quick to implement a php class, and I could quickly add the conversion to my existing conversion API. Convert a postcode to geohash anyone?

Updating the documentation noticed the API was last updated in 2005 – gulp, how time flies! Anyway as a celebration have upped the throttling on the API, now three times the previous limit. Running on much improved hardware than when it was launched so maybe the limit can be tweaked even more, will run some analysis of its impact – it already seems the API is a minor part of the overall load on the server – particularly against the Google Earth layers.

Export multi-destination (or dragged) route to Google Earth

Thursday, December 27th, 2007

Love keep adding destinations to your route, or even dragging the route to refine perfectly to your needs in the directions feature on Google Maps? But frustrated that this feature isn’t available in Google Earth?

… No, not implemented this feature for Earth (wouldn’t that be something!), but as a stop gap its a way to export your newly created directions on Maps, and open them in Google Earth! You get a freshly created folder containing each section as a separate route, ready for use as ‘one.

Multi Destination routing in KML for Google Earth

Playing with (geo-enabled) Full-Text Searches

Thursday, December 20th, 2007

Recently I have been playing a lot with Sphinx full-text search engine, in particular with regard to indexing the Geograph archive. (a bit of background – Geograph has a fairly good homegrown site text search – but its not full text, so many queries will not return that many results – not to mention been based on MySQL ‘like’, so is pretty slow – so a full text search is the next level). And I have to say I am liking it a LOT, in fact I would say I am a fanboy :)

So to that end of created a whole bunch of demos based around the flexible indexing it provides, location based searching is even possible!

At the most basic is simple text based search, one point of note, there is no pagination, simply add more keywords (including negative) or grid references to refine the selection.

Next is a ‘auto-complete’ style image finder, this is designed to find ‘that image’ quickly, in a similar way to the above but shows the results in a autocomplete box immediately!

A refinement of the first is search with location, this allows you limit the search to near a particular Grid References – this is particully cool in that there is Sphinx powered auto-complete for place names for finding GRs. (a real auto-complete not a like the search in the previous one pretending to be one)

This is all building towards the Illustrator demo. Which from a block of text attempts to find relevent images. The idea is that a (geolocated) news article, walking route, place description and such could be automatically have relevent(ish) images shown. (an example demo here)

(a few more ‘toys’ can be found in GeographTools!)…. Try them out and let me know how you get on…

I have learnt a lot about search indexing from this, including how to perform location searches in the index (I know latest versions of sphinx include a lat/long based geosearch – but I think this r-tree method in text has better scalability), and how to create an autocomplete function with sphinx. If anybody is interested in these, they will eventually make it into the geograph codebase, or let me know and I might make a separate post.

Interestingly (huh?), it was actually creating a ‘autocomplete’ textbox for finding trigpoints (which included the forerunner to the sphinx location search in but implemented in mysql), is actually what inspired me to actually go the trouble if figuring out how to install Sphinx on linux, which I have been interested in for a long time! – that is also now sphinx powered for text searches :)

As a side note have now reached the ‘linux sysadmin’ level that I can compile it on Geographes servers, yay! But I do worry for the sanity of others due to this (a little knowledge is a dangerous thing!)

Google Earth Version Stats (Dec’07)

Friday, December 14th, 2007

 Only a quick post as its late, but just noticed this report had finished generating, took rather a long time, as just found our stats package has been mangling GE’s useragent string – anyway enough rambling, I know you just want to view the stats:

 Dec 2007 :: Google Earth versions accessing links on nearby

… make of that what you will – haven’t really drawn any conclusions from this…

(last set)

A winter spruce up…

Saturday, December 8th, 2007

Have finally got round to (almost) sorting a issue that has plaguing this site for a while, namely a lack of header/footer for site pages. Primarily from laziness, but also due to the mixmash of server scripting languages used to power Nearby. Anyway the upshot is can now relatively easily edit the top/bottom menu areas. So to celebrate there is now far more links at the top of the page.

Have also taken the opportunity to publish a revised homepage I tried creating a while ago, I am not totally happy with it but think it possibly an improvement (or at least a declutter) of the old one, sadly no new features released tho!
(yes this is the first time in over a year an a half have done substantial development in areas other than the Google Dabbles or GeographTools pages)

MGRS fix for < 1km gratitules

Thursday, November 29th, 2007

Following the update in July for hiding the 100km numbers from the gridline labels, it seems the same fix broke the sub KM lines, thanks to a comment on the original post for letting me know.

Anyway, the online hosted version has been updated (and checked at all scales as best I can!), and the same file pushed into the downloadable zip for the offline version, so can download the latest code from the file. And just for completeness the diff.