Foxit Reader 3

Tuesday, 23 December, 2008

Foxit Reader 3 has recently been released and it’s a worthy upgrade. Again, you can download the ZIP and simply extract the EXE in to any directory you want meaning you can run it from a USB stick). At 7Mb, and 1 file, it’s a pleasantly small and simple bit of kit. As with previous releases the speed of rendering PDFs is excellent, with functions supporting thumbnails and layers added in this release. The latter is particularly welcome as GeoPDFs (and layers) have become far more prevalent. Thoroughly recommended.

Major usability upgrade in ArcGIS

Wednesday, 17 December, 2008

Yes it’s true, ESRI have finally ditched the requirement for the use a USB dongle (or old style parallel port dongle) in favour of a keyless authentication system. OK, so this is not a “feature” related in anyway to spatial processing, but it finally means the whole rigmarole of dongles is gone. Much of this patch is actually related to laptop usability. I’ve blogged before about the frustration of using a dongle based system and I think this move probably reflects the increased use of ArcGIS on laptops. In fact many of the other fixes in this patch related to laptop use and specifically the need to hibernate laptops and plug/unplug the dongle. I previously had set up a couple of batch scripts to manually start and stop the license server to get around this but its nice to see it sorted out properly.

GeoPDF Generation

Thursday, 4 December, 2008

I’ve been fiddling around with GeoPDF generation in ArcGIS 9.3 this week and its been quite frustrating. The added functionality is really very very good and considering this is their first release it works remarkably well. I have even had some maps submitted to the Journal of Maps that make good use of vector layers within the PDFs (and indeed some authors who don’t realise they are exporting GeoPDFs).

I am in the final stages of PDFing two large (in terms of filesize) maps, one with a large raster backdrop and some complex vector layers, the other with a very large raster backdrop!! The first map was being rendered almost exactly “as seen on screen” and incredibly quickly. However ArcGIS appears to be indiscriminately rasterizing some elements of the map and leaving others as vectors. It makes for a bit of a mess and to be honest its hopeless; really not fit for publication. I then switched to trying Terrago’s MAP2PDF which uses a totally different rendering engine, is much slower, but has greater control over the final product. It also deals with vector layers correctly and the final output looks much better. However it doesn’t work with one of the clipped raster layers properly, although a fix is supposedly coming.

The second map is really just a very large raster and needs to look good, but retain a small filesize. Whilst there is granular control in ArcGIS on the resolution, the JPEG “quality” is, well, pants! There are only 5 settings and only setting 3 or 4 is worth using. However the difference in quality can be significant. I wasn’t happy with the filesize/quality trade-off the ArcGIS 9.3 produces, so switched back to MAP2PDF which took 5 minutes to render the map before it crashed ArcGIS. Solution? Go back to ArcGIS 9.2 which seems to produce a better raster product

So there you have it, my totally unscientific and cursory exploration of producing PDFs of two complex/large vector and raster maps. This suggests that it is a far from mature product area. GeoPDFs are really starting to hit the big time and ESRI/Adobe appear to have big plans. But no one has got robust processing routine…. yet. I have no doubt that Adobe will get there, but its going to take time.

UK Location Strategy

Wednesday, 26 November, 2008

The reports just keep on rolling. This time we have the UK Location Strategy published by DCLG (and the GI Panel). It covers much old ground and gives a rather uninspiring action plan on p17. All Points Blog also discuss this and, somewhat fairly, note that “they do highlight how complex it can be to actually get them done!” However this has to be taken within the context of the 1987 Chorley report and the 1997 followup. Now that was only 21 years ago and, well, pretty much all the same points were covered back that.

THe OS debate continues…. this time it’s serious!!

Tuesday, 25 November, 2008

The Pre-Budget Report published yesterday was obviously designed to get us to “spend, spend, spend”, but the small print contained much of interest to the debate on trading funds and publicly collected data (not just by the OS). Many feathers seem to have been ruffled in Whitehall, probably not least those of the Home Secretary; “crime maps” is probably rapidly becoming a rude phrase! Anyway, both Ed Parsons and Charles Arthur (FoD) have succinctly outlined the key parts of the document and some of the things they hint at.

Time will tell where this is all heading….

BNP Membership Mapping

Thursday, 20 November, 2008

The news over the last few days has been awash with items on the leaking of details of BNP members in the UK. And of course it didn’t take long for a Google mashup to be put together, although, even with the caveats that this mapped post-codes, not individual addresses it was largely misunderstood (Charles Arthur posted about this yesterday) and subsequently replaced with a “hot spot” map which is all very pretty by, well, largely meaningless. There was a nicely considered piece over at thinkwhere saying, in as many words, that on its own, the map doesn’t say too much about BNP membership as we are more interested in understanding the societal implications. This means correlating this list with measures of deprivation, population density, voting results etc etc. This can begin to identify clusters of membership and possibly why they are there (and that’s before you get in to issues of membership by occupation).

CORONA Mission

Wednesday, 19 November, 2008

For those not familiar with the CORONA Mission, it was the original US spy satellite programme that operated from 1958-1972 (and was declassified in 1995). Of many “firsts” in satellite remote sensing, it was notably the first mission to provide photos taken from space through the launch of the camera in to a pre-selected orbit and, after image capture, the return to Earth of a capsule containing the film for retrieval by aircraft or boat. Whilst the first successful image was not acquired until 1960, it went on to capture over 800,000 images at a range of spatial resolutions.

US spy satellites are designated with a KH (for KeyHole) acronym, with CORONA ranging from KH1 to KH4. Spatial resolutions are good ranging from 7.5 m, with many at 2.75 m and some at 1.8 m. Stereo imagery was also collected for some missions. Not only does this remain “competitive” with contemporary commercial systems, but it also provides an excellent historical archive (although note that its panchromatic photography, not multi-spectral imagery). Given that Landsat-1 didn’t launch until 1972, this provides a valuable archive for a variety of applications. All the imagery are available for purchase from the USGS at $30 per frame.

And of course it wouldn’t be appropriate to conclude this blog without a brief comment on the continuing US spy satellite program. Again, Wikipedia has a nice summary of current known programmes. The successors to CORONA were initially film and then, with KH11, digital. Resolutions were commonly 15 cm (using what would appear to be a Hubble space telescope pointing at the Earth), with the expectation that the current KH13 is probably sub 5 cm.References

Wikipedia
Project CORONA - Keith Clarke, UC Santa BarbaraUSGS

World Toilet Day

Wednesday, 19 November, 2008

Yup, that’s right its World Toilet Day! Whilst us Brits have always had a tongue-in-cheek snigger about toilet humour, typified by Adam Hart’s wonderful Thunder, Flush and Thomas Crapper and, appropriately on WTD, a piece (or piss?!) by BBC News item (from TearFund) titled Britons’ toilet pastimes revealed, there is a slightly more serious side that WaterAid/TearFund are trying to get across. Namely that 2.5B people worldwide don’t have proper sanitation. And of course:

“One gram of faeces can contain 10 million viruses, one million bacteria, 1,000 parasite cysts and 100 parasite eggs.”

At the very least have a go at playing TurdlyWinks. Go on, you know it makes sense!!

Python Training

Monday, 17 November, 2008

I’ve just returned from 2-days of of training in writing Python code at ESRI UK, reveling in the delights of Aylesbury. As I’ve mentioned in numerous posts, scripting is finally “back in” at ESRI and Python is the language of choice (although you can script with other languages). So much so that there is a training course on it. Don’t expect it to be an introduction to Python, although to Python is introduced. Rather it is an introduction to developing ArcGIS scripts with Python and how geoprocessing functionality is accessed. Our trainer, Rob McPherson, was excellent and very knowledgable having clearly done quite a bit of Python development. In order to get the most out of the course its worth having already used Python to do some scripting, but you don’t need to have done so.

Introductory material includes the geoprocessing environment, python, tools/environment settings and the programming model. These lay the ground for using and manipulating the functionality exposed through describe, enumeration and cursor objects. The course concludes with integrating scripts back in to ArcGIS and debugging.

Interestingly the course is delivered using PythonWin which isn’t shipped with ArcGIS (IDLE is the common IDE that accompanies Python). However it is easy to use, offers a reasonable attempt at highlighting text and offering object choices and provides a debugging environment. One of the main downsides is that you can’t kill (at least I don’t think so) a Python script that is running.

Which brings me on to the next point, namely that it seems far better to run all your own scripts from PythonWin (or IDLE) without starting up ArcGIS at all. It appears faster and more stable. In fact, avoid the IDE entirely and run it directly in Python by double-clicking on the .py file. Anyway, a good course that is well worth attending by anyone wanting to develop scripts or needing to build models. Apparently an “Advanced” course runs in the US, but is not currently available here. I hope ESRI UK can add this to their portfolio.

Best Training Course?

Friday, 14 November, 2008

I’ve recently been on training courses at both Leica and ESRI UK and therefore thought it an opportune moment to compare them. And the verdict? Well, ESRI UK provide, by a significant margin, the best biscuits. No question!