Hot Cross Buns

Saturday, March 31, 2007 at 06:48:50

My 6-year old daughter asked me this week why we have hot cross buns. Before I had a chance to look at Wikipedia and explain that they are symbolic of Jesus dying on the cross and are typically made without dairy products during Lent, she promptly informed me that Jesus died on a hot cross bun!!

If only all things in life were so simple!

Autoresponders, email and alias’

Friday, March 30, 2007 at 09:03:52

I contacted a well known GI company this week, sending an email to what (obviously) was an alias. My expectation was that this would get routed through to the person dealing with queries related to this alias and respond appropriately. In response I received the following reply which, as you can see, notes that the person will be back from leave on 11 June 2007. A two-and-a-half month wait seemed a little on the extreme side!! Contacting someone else directly in the firm finally revealed that the alias actually forwarded to multiple addresses; no one had got around to answering the email and this particular person had their auto-responder on. Sometimes email is just a little too easy and you can really send out the wrong message to potential customers.

What do PIN and GIS have in common?

Friday, March 30, 2007 at 08:55:02

Well not much really, except I can’t stand people saying PIN number. IT’S NOT A BLOODY “PERSONAL IDENTIFICATION NUMBER NUMBER”!!!! Just as it isn’t a geographic information system system. It’s PI number, PIN, GI system or GIS. Definitely NOT PIN number.

Personal Geodatabases in ArcMap 9.2

Thursday, March 29, 2007 at 12:42:04

As many have discovered, personal geodatabases in ArcMap 9.2 are not backwards compatable. Ho hum, thats nice and helpful. For those who use personal geodatabases this is causing quite some headache in terms of migration and mixed versions of software. 9.2 is not able to save in previous versions either, however the benefits it offers might well be worth using and include support for double precision and the new cartographic features (yes, you might actually be able to throw away those coverages). Spatially Adjusted briefly mentioned this problem late last year and have links to a blank/empty versions of personal geodatabases for 9.1 and 8.3 that can be used in 9.2 to store data in. A work around at least.

Toilets of the World

Monday, March 26, 2007 at 08:06:06

I saw this in my local bookshop and had to buy it. This obsession with toilet books harks back to 1997 and Adam Harts quite fantastic Thunder, Flush and Thomas Crapper: An Encycloopedia. Now out of print, it is a real classic and home to such anecdotes as a detailed explanation of the double-bend siphonic flush action. Anyone who reads this book must look at the item on “astronauts” and, my favourite, “australia”.

Anyway, a slight digression. Toilets of the World has, as might be expected, pictures (and explanations) of toilets from around the world. A great book to leave in the, well, toilet, and dip in to. El Porvenir airport’s toilet (Panama) is great. The Whiskey Cafe in Montreal, interesting….. and Rothesay Pier (Isle of Bute) is a real tribute to the Victorians (and one I have actually been to!).

Google Maps support for GeoRSS

Friday, March 23, 2007 at 10:28:30

Ed Parsons gave the heads up on the Google Maps blog news that support has finally been extended to GeoRSS. Bout time too in my books; GeoRSS is rapidly emerging as the de facto choice for lightweight distribution of vector data. And the fact that the OGC have a white paper on the “standard” is good news. Its not as rich as GML (or KML for that matter) but its good at its target market.

At the Journal of Maps we use WorldKit to suck the abstracts for our articles out of a GeoRSS file and display it on the main page. We’ve now add a Google Maps link for those wishing to use it. Having quickly played with it, support is not quite what I like, but its OK. Notice for example the different display of points and polygons; polygons also remain non-clickable whilst points are OK. I’m no expert on the Google Maps API so I’d been interested to see if some of these behaviours can be changed.

Viewing Map Projections

Wednesday, March 21, 2007 at 10:40:32

Ever wondered what a Raisz Half Ellipsoidal projection of the Earth look like? Well you do know because its shown on the right! The Map Room points to the Global Map Projector over at NASA which allows you to transform any equirectangular map image into another projection. Really is an easy (and fun!) way to explore the effects of different map projections. Also a very good way of generating bespoke world images for presentations; The Map Room suggests a visit to flatplanet to grab some JPG files from their vast archive of interesting world images to play with.

Area is a standard geometrical property right?

Tuesday, March 20, 2007 at 05:56:20

Well you would have thought so wouldn’t you? We have the following simple geometry:
<brpoints: they have a location (x,y)
lines: they have a location based upon a start and end point, in addition the have the properties of length and orientation
polygon: they have a location based upon coordinates of the points making up the feature, and also have properties that include a centroid, area and perimeter. There are also other things you might want to calculate including min/max dimensions, maximum bounding box etc

So thats straightforward. OK, so if you want the basic properties you would expect your GIS to be able to calculate at least most of the “basic” properties “out of the box”. Lets take ArcGIS 9.1 as an example:

points: well it must be able to record the point otherwise you wouldn’t be able to see it. Can you get the coordinate? No.
lines: Ditto, so we can’t get the start/end points. Orientation. No. Length. Errrr. No.
polygon: Ditto for points again. Perimeter. No. Area (and, I might add, one of THE original reasons that a GIS preferred to manual calculations). Errr. No.

Well its not strictly correct. All of the above features can be extracted in ArcMap using some good ‘ole VBA code. Now thats nice and easy (not!). Some of them can be extracted using ArcToolBox. Ah, you need the underlying ARC/INFO and, more importantly, the more expensive license for it. The points can also be extracted by exporting in an ASCII format although, yes, you need ArcToolBox. What started all this off? A student asking if they could calculate area as surely that must be easy! No wonder there is an over-proliferation of add-ons like ET Tools, XTools Pro and Hawths Tools. I know ESRI can’t program everything; BUT REALLY. This is elementary geometry.

So am I getting increasingly frustrated with ESRI’s banal minimalist interface that fails to give you easy access to the fundamental underlying geometry? Yes. The now outdated and poorly designed interface that is littered with toolbars, many of which you have to pay for the functionality? Yes. The over-reliance on ArcToolBox to access functionality in the well documented and programmed ARC/INFO that they couldn’t be bothered/have time to re-write properly? Yes. The over-proliferation of tools in ArcToolBox under strange group headings, with different groups having the same tool name that does different things (e.g. Project, Buffer). Yes. The bungling in-out mentality with the GeoProcessing Wizard (in in 8.x, out but turn on-nable in 9.0, removed in 9.1 to be replaced with a pathetic help screen, in as a download in 9.2). Yes. Please make up your mind!! Either make the ArcToolBox tools easy to use or write the GeoProcessing Wizard properly.

Rant over and I no doubt stand to be corrected on several things!

More GPS Data Logging

Monday, March 19, 2007 at 13:05:30

A solar powered GPS data logger has been doing the rounds, from Vector One and Free GeoTools (who links to the specs page). This neat little GPS unit has a SIRFStarIII chipset (32 channel) with 8mb of memory. Its (of course!) solar powered, with a foldout LCD screen so that it can be used as a “standard” GPS or simply set to data logging. Its also BT enabled.

Given my previous review of the Sony CS1 I think we are going to see more devices in this form factor (partly because us NeoGeographers are collecting data not, navigating). It seems sensible for there to be a convergence in this area and the Keomo certainly seems to do that with solar, blue tooth, data logging, form factor and regular GPS functions. This is going to be in interesting area of development.

Copyright or database right… Does it matter?

Tuesday, March 13, 2007 at 11:59:42

One of the follow-on outputs to the GRADE Project from my report on the Use Case Compendium of Derived Geospatial Data deals with the legal aspects relaing to geospatial respositories. In particular there was a need to look at the framework for designing a licensing strategy for the sharing and re-use of data submitted to a repository. This part of the project was led, and reported on, by Charlotte Waelde at the AHRC Research Centre for Studies in Intellectual Property and Technology Law, Edinburgh University. Whilst my compendium highlighted the problems relating to data re-use, particularly with respect to the Ordnance Survey (as this is where UK HE has the greatest experience), Charlotte has taken a step back and assessed the basis for accepting the terms and conditions upon which the data use are based upon. And the conclusion that she has come to:

geospatial data (generally) does not come under copyright, but rather database right. The former covers original, creative, pieces of work (and includes things like photos and maps), whilst the latter is designed to protect databases that have been collated. Her argument (and you need to read the complete document) is that products such as Mastermap are covered by database right only.

This has some important implications, but don’t read this as a free-for-all grab at everyone’s geospatial data; its not. I would like to highlight the following point that Charlotte makes in her report (and I quote):

A lawful user of the database (e.g. the researcher or teacher in an educational institution) may not be prevented from extracting and re-utilising an insubstantial part of the contents of a database for any purposes whatsoever.

This has the following implications:

  • 1. If you’re a licensed user (e.g. Digimap user) you can use an insubstantial part of the database as you see fit (although Charlotte explains that the term “insubstantial” is still a little vague but possibly <50%)
  • 2. This includes re-distribution of that insubstantial part, creation and re-distribution of derivative data and publication of figures directly relating to the utilisation of the data or any derivatives.
  • 3. Any terms and conditions applied in relation to the original license are null and void for the insubstantial part

Of course does any of this really matter to anyone? Well on one level you could argue no. Those that are happy with the status quo, utilise geospatial data and publish within the “restrictions” are not affected in any way. There are those that find some of the current restrictions irritating and just want a “sensible” license. Finally there are those that want to get well on the way to “freeing our data.”

Whatever our outlook is, these are important and highly relevant conclusions to draw and will effect us all in the geospatial community. Indeed Europe as a whole (as this relates to the European Database Directive) is going to have to take a deep breath and work out the next step. Not least, the HE communitys two biggest bug-bears (with the JISC-OS license at least) are addressed in that, theoretically:

  • 1. No copyright subsists in derivative products and these would be freely distributable (as long as they are not “substantial”)
  • 2. For the same reason, academics would be more or less free to publish whatever diagrams they see fit

So really the big question is:

what happens next?

GPS Data Logger

Monday, March 12, 2007 at 11:01:30

I’ve finally caved in and bought a GPS. Being not remotely interested in satnav, I have had limited need for a GPS, however it was Neogeography that finally got me interested in some of the potential uses. In it, Andrew Turner reviewed some GPS loggers. No screen, limited settings, just data collection.

On the this years first year field course, I have liaised with the Rights of Way officer at Carmarthernshire County Council and the students will be going out and surveying potential rights of way using “definitive” mapping from the 1960s. Clearly then its beneficial to have tracklogs from a GPS; absolute accuracy is not esential for this task and low-cost units provide an ideal piece of kit that is “fit for purpose”.

Our department have a horde of Garmin Gekos used for various purposes and these are fine for the task (provided you have the bespoke usb cable to access the tracklogs). I therefore thought I would purchase a Sony CS1 GPS logger to see how it would fare. The first thing to note is its diminutive size, single AA battery that provides upto 14 hours of continued logging (or more if you can get ahold of a Li-Ion). The unit comes with ~31Mb RAM which provides over 300 hours of logging or somewhere around 75000 points. Thats bloodly good in comparison to the competition. Its a standard 12 channel receiver, although no EGNOS/WAAS by the looks of things (not explicitly stated either way, but the “claimed” accuracy suggests not). There is only an on/off button and no settings. And this is probably the units greatest weakness; the logging interval is 15s and you CANNOT change it. The CS1 was designed for tagging digital photos and 15s is fine if you are walking. Not so good if you are cycling or snow boarding (SONY: can you please make this a changeable setting).

In operation the unit works just fine, taking around 1min for initial satellite acquisition. Probably best to put it on the top of a rucsac to give it maximum aerial visibility, however stick it in a plastic bag to keep it waterproof. When finished, you can use a standard mini-usb cable to attach it to a PC and, low and behold, it appears as a drive letter in exactly the same way a flash drive would. Sony has got this part spot on. Just copy your tracklog on to your PC and run gpsbabel to convert it in to something more useful. Its in NMEA format so use the following command line to convert to KML and load straight in to Google Earth:

gpsbabel -i nmea -f 1.log -o kml -F 2.kml

I can’t believe how simple this all is!! You can alternatively convert it to GPX and then in to SHP for loading in to a GIS. Many thanks to Tim Woolford for the heads up on the Sony unit.

PosiPix Vision

Saturday, March 10, 2007 at 07:28:32

Tim Woolford, MD of Trek Wireless was down in Kingston talking about the rationale behind their Posipix product. Trek Wireless started out by driving around central London and taking fore/aft photos of all the streets. The high res photos are then sold on, en masse (e.g. Navman) or singly (through the Posipix website). They take a pragmatic approach to the distribution of spatial data (imagery) and haven’t gone down the complex spatial database route. Rather, all the photos are JPEGs so they have taken advantage of specifying the coordinates in the EXIF headers. They’ve also marked up all the photos in KML so they can be viewed in Google Earth and, after Google’s announcement a few weeks ago, all this spatial information indexed. After feedback from potential customers, they realised that in order to sell the photo, people want to know what’s in it. So they have been classifying all the imagery noting “points of interest” within them (tourist attractions, theatres, restaurantsm shops). And, of course, all of this is discoverable via Google or their own search.

Tim has a vision for street level photography that surpasses this though. The navigation sector is particularly interested in the product; its always good to be able to see what your final destination looks like. However it is the integration of smartphone and satnav that offers exciting possibilities. In this “brave new world” Tim sees many smartphones being GPS enabled within 2 years (at 3GSM this year one chipset manufacturer was offering the $1 GPS!) so one possible scenario would be ordering a Posipix photo of a destination over the web and having automatically sent to the phone. The navigation software automatically pulls the destination coordinates out of the EXIF header and plots a route which is displayed on the smartphone. If you are meeting anyone (at a theatre for example) you could picture message them the photo for the same purpose.

It’s a nice idea works simply at a technical level and also at the cognitive level because people want to see where theyh are going. Of course it needs implementation at the phone level which isn’t hard but not here yet. It’ll be interesting to see how this develops over the next few years……

geo URI: the way forward?

Sunday, March 4, 2007 at 19:50:22

What the hell is a URI you say? Well if you just clicked on that link, you will have seen that a URI is the underlying protocol behind a hyperlink that generates a network request when you click on it. So if you want to go to this webpage you will see that the protocol is “http”. There are many familiar ones; mailto: and ftp: for example.

Well the geo:URI scheme suggests taking hyperlinks spatial thus allowing you to divorce the content (i.e. location) from the way it is viewed (e.g. Google maps). It has been submitted to the IETF as a draft ultimately with the aim of it becoming a RFC specification.

Part of me likes this proposal as it elevates the importance of spatial information and should make indexing “space” for search engines easier. Whether it becomes implemented depends largely upon…. Microsoft and we know what they are like for standards. Anyway, the geo:URI people have produced a Firefox extension which handles geo URIs (using Google maps by default) so you can now go here.

Editing audio

Friday, March 2, 2007 at 06:57:08

I regularly record either lectures I give in the university or at conferences (see my homepage), as well as by guest speakers. After a bit of research I purchased an Olympus WS200 last year. Its a USB stick sized recorder with a detachable memory stick. It has an internal mic, as well as a connection for an external one, and runs on a single AAA battery. The quality of the recording is excellent although it uses WMA v8 which has caused me quite a few headaches. I don’t like distributing audio using WMA because, whilst it undoubtedly is better than mp3 and well supported, it is a closed codec. So I have spent quite a while looking at painless (and simple) ways of dealing with the files.

In summary, I needed to find a transcoder to take it from WMA to MP3. If you put a search into Google you will find that it comes back with a whole load of “freeware”, shareware and spyware guff. Not much help. So some more searching later I came across Switch by Australian software house NCH who specialise in audio products. The produce a free-to-use version of Switch which happily transcodes between many formats including WMA and MP3. So this did the transcoding for me.

I also have recourse to crop and split the MP3s I have recorded. Rather than having to save the WMA to WAV, edit and then save to MP3, I wanted to find something that would edit the MP3 directly. And that is exactly what I got with mp3directcut. It works out byte offsets for the mp3 file and can cut out segments, split files, paste new segments in etc. Not the prettiest interface but its fast and reliable.

Even my Aunt has ArcGIS 9.2!

Thursday, March 1, 2007 at 08:21:06

OK, well not strictly true. Well, its not true at all, but it might as well be. ArcGIS 9.2 shipped mid-November to… commercial customers. Fair enough, they pay for it. Of course all the “cutting edge” work in research institutions will just have to wait until the guys at Redmond have bought a few new CD burners. Over on the far, fair, shores of this blessed isle, where we only receive 1 delivery a month, it was clearly just too much like hard work for ESRI to be able to deliver more than 25 batches of CDs at a time. And, once ESRI UK received their shiny batch of CDs they seemed only to be able to send them out at a rate of 1 a day. And just so they make it easy for staff, it goes out alphabetically, by institution. OK for Aberystwyth, not so happy for York. Except the machinations of senior management at ESRI had further plans. Instead, for those “heavy” users of GIS (incorporating ArcIMS/SDE) and, in particular, those on the only single honours GIS degree in the UK, no we’ll make them wait LONGER. Yes these institutions really aren’t important and aren’t training the next generation of technicians and users. So much so it doesn’t matter if we let them wait four months.

Not really what I call service…

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