Commisioning Aerial Photography

Dot Net Webs

Hello.

Please see http://www.virtualhorsham.com which is currently being used to drive traffic to http://www.visithorsham.co.uk (which itself makes extensive use of Virtual Earth internally).

There may be an opportunity available to specify a commission for some aerial photographs that could be used to overlay the outdated areas on the areas covered by these map.

Ideally I would like to replace the area covered by the www.virtualhorsham.com map when it is set at the 200 yard range. I am not bothered about the residential areas at the left and right sides of the screens but I would like the whole of the Town Centre and Park to be visible at the highest map resolution.

Can anybody advise me about what would be involved in taking such photographs. I have no idea of the capability of the type of cameras that are used for this purpose. For example would this be possible in a single pass or would multiple passes be required One other constraint we have is that the maximum allowed altitude for the aircraft involved would be 1000 feet.

Also are there any other tips for commissioning aerial photographs for use with Virtual Earth.

Many Thanks

Duncan Garratt

In answer to your question, yes new aerial imagery can be substituted in virtual earth from a technical point of view. The cost of acquiring the imagery is extremely expensive, and requires specialist cameras to do the job. The question is does your site justify the expense, which could run into 10k or more, and would require regular updates e.g. per year.

Getmapping PLC is the specialist in this area and it may be worth speaking to them as a starting point.

Duncan Garratt

Dot Net Webs

Hi Duncan

Thanks for your reply.

The cost for this commission would be shared across several projects and would not be specific to this website. There is already in place a (non web related) commission for some aerial photography in the local area and we were wondering what would be involved in taking some Virtual Earth specific photographs on the same 'mission'

Even if we only got a single useable shot of the main Town Centre area it would be worth overlaying the existing tiles, many of which have changed considerably since the original photographs were taken.

I do not think we would need to regularly update the photographs. The town has had a lot of development since the existing photographs were taken some 8 years ago. This development phase is now complete and there are not likely to be any major updates for the foreseeable future.

I guess the question I am trying to ask is whether any aerial photography company would be able supply images suitable for use with Virtual Earth or does it have to be a company that specific have set up to take these sort of photographs. e.g are the 'specialist cameras' very specific to this sort of aerial photography or will existing aerial phography companies have access to them.

Obviously I will discuss this with the company in question but I just wanted to know the 'right' questions to ask from a Virtual Earth developers point of view.

Thanks again.

Duncan Garratt

Rob Blackwell is the expert regarding VE map tile substitution, and his company is based here in the UK.

www.aws.net

Hope this is of help

Duncan Garratt

SoulSolutions

Yeah if Rob can help he has written several great articles on tile servers.

We worked with Microsoft Australia to get some aerial photography over three locations back in Jan for Australia Day.

The photography should come back as a north aligned geotiff from the supplier. I don't know what the cost was but once you have this for a small area map cruncher is great to correct any alignments and generate all the required tiles yourself.

For another project we build a tile generator that takes a folder of geoTiffs and processes all the required tiles from a farm of computers. For large areas with high resolution files it is too hard and slow to do it by hand with map cruncher.

Another issue is hosting all the tiles, the latest version of map cruncher supports uploading direct to amazon S3. This is a very cost effective way to store and serve the data, although i hear mixed reviews of it performance.

If you need any help with processing the geoTiff files please let me know.

John at soulsolutions.com.au

Dot Net Webs

Thanks Duncan and John for recommending Rob Blackwell I have sent him an email.

In the mean time. Please excuse my ignorance, I hadn't heard of a geoTiff until you posted but from what I have just read I am assuming it is a basically a Tiff file with geographical data emended into it

Bearing in mind I am only looking at a very small area (around 1 square mile) could we not just use a flat, North-aligned image and use map cruncher to align it using the existing features (roads, railway lines etc.) To be honest the alignment doesn't have to be pixel perfect. I just want to have a relatively up to date image of each of the buildings featured in our application.

If the above is possible I am just wondering what the practicable implications of taking such a photograph (or series of photographs) is.

Regards

Rob Blackwell

There are a number of companies that supply aerial photography

You could try - Simmons Aerofilms - http://www.simmonsaerofilms.com/

Also see the video referenced here http://www.robblackwell.org.uk/ p=46 may be of interest.

Some people have experimented with DIY hot air balloons with digital cameras slung underneath.

It all depends on the accuracy you need - obviously the professionals are after high accuracy, but my feeling is that you could probably get away with a more amateur endeavour - the results from MapCruncher are suprisingly good!

My expertise is more on the mapcruncher / custom tile server side than aerial photography per se - but feel free to call me if we can help - 01473 834560

Thanks

Rob.

Dot Net Webs

Hi Rob

Many thanks for your reply.

The video link on your website is most interesting. According to the presenter the aim is to update Virtual Earth by the end of 2008 with high resolution pictures for everywhere in Europe with a population of over 50,000 people. Horsham's population is around this figure so with a bit of luck we may be included in the update. I don't suppose anybody knows if an update schedule is available

I have just realised from looking at your website that it was you who wrote the Virtual Earth article in this month's .net magazine. It was this article that prompted me to think about the possibility of attempting to replace some of the tiles in the Horsham area. It was great to see an article about Microsoft technologies in .net magazine which, despite the title, normally takes focuses on other areas.

Thanks again to everybody who has replied to this thread. I think that if we can get a suitable, cost effective set of pictures for the Town Centre area it will be worth doing.

Regards

Gavin

Dot Net Webs

Hello again

I have just found this 'amateur' approach example on the MapCruncher website:

http://research.microsoft.com/mapcruncher/Gallery/Forks/

This seem to cover roughly the scale I am looking at. The only thing that concerns me is that the existing tiles are drawn before the replacement tiles are overlaid causing a significant delay in zooming on a slower connection. Is this just because they have included both layers for demonstration purposes i.e. is it possible to complete eliminate the existing tiles in the relevant area

Regards

Gavin

SoulSolutions

Gavin,

would I be correct in saying that you represent an area that wants to update their imagery on Virtual Earth That is, would the ideal situation be that the updated imagery became part of Virtual Earth, everybody would get it, and you wouldn't have to deal with hosting and using layers for your specific VE application

I ask becouse we talked through this concept (dealing with the idea of entire countries) of external stakeholders sourcing, licensing and creating tiles for Virtual Earth. I see it as a win win situation for Microsoft and the stakeholder. The stakeholder pays for the imagery and processing and gets their area updated, Microsoft hosts the data and get s a better product, everybody is happy

The finer detail could be the killer but let me know if this is of interest as I would like to start a disscussion with MSFT about the concept, having a real world case would help the cause.

John.

Duncan Garratt

I like the concept of stakeholders being able to substitute tiles for VE Data. There are a lot of areas in the world, such as third world counties that have poor or limited VE data. I remember reading a post on this forum, about an island that wanted to put its road layout on VE, and the data was stored in ESRI shape file format. What you are suggesting would be ideal for such purposes. The issue of Microsoft publishing the data is a tricky one, due to quality assurance of the data. At government level I think the last has merit, as what you are proposing is a way for third world counties to have their own mapping systems, that is public, and for everyone¡¯s use. Such an approach I would see as a major step forward in mapping the entire earth for the benefit of all, something the GIS community, and the wider public have been crying out for.

As the map data for many of these countries does exist, I think there is a golden opportunity for Microsoft to work with governments in encouraging them to use VE as their publishing system. The fact should not be lost that Ordnance Survey are finally beginning to realise that restricting the use of cartographic data, by way of price or otherwise, does have a negative impact on a country¡¯s economy.

As we have seen in the last year a number of major travel companies are now using VE or Google Maps, and the public in the developed world are increasingly using these systems, when making choices regarding travel, property purchase, investment etc.

I understand Microsoft are interested in helping the third world, and VE is one way of aiding third world development, through the use of high quality map data, initially through road data, but later with aerial imagery.

Duncan Garratt

Rob Blackwell

Gavin,

It's relatively easy to hack the Javascript in the Virtual Earth Control so that it accesses your tile server *instead* of the Microsoft tile servers, and this would eliminate the drawing of existing tiles.

In earlier versions of the control, this was the only way to do custom layers and was described in my article http://www.viavirtualearth.com/vve/Articles/RollYourOwnTileServer.ashx - this is a bit old now, but might be of interest to you.

Rob.

Dot Net Webs

Hi John

This would absolutely be the best solution for us. If approved, funding for this project will come from local government and although I don't speak for them I am sure that they would like anybody using Virtual Earth to have access to the latest imagery rather than restrict it to those using a specific application.

We are only talking about a very small area but I agree entirely with your concept. It is only really early days for us but I would gladly assist you with any information required to form a 'real world' case study.

Incidentally I would like to thank Jeremy Elson from the MapCruncher team who has given me some invaluable advice and convinced me that it is certainly worth using a low budget MapCruncher based approach for this project.

As this approach will likely provide less than optimum image quality for use on Virtual Earth I guess it raises the point that John made: How would quality be assured using the 'stakeholder' approach I think some sort of approval process would be required.

Regards

Gavin

Dot Net Webs

Hi Rob

Many thanks for this. I will have proper read of your article as soon as I get a minute.

Regards

Gavin

SoulSolutions

Gavin,

Can you send me an email with your contact details

My email is John at soulsolutions.com.au

I agree the best solution for you to move forward is to see who can supply quality imagery at a good price, then use map cruncher to generate the tiles, It sounds like there won't be too many so you could host them yourself or use Amazon S3.

In regards to replacing the VE tiles the article shows how to replace the entire tile server, which may not be exactly what you want, but you could have some sort of proxy that redirects to the VE tiles where you don't have the updated ones. There will be load on your server to do this as every request for tiles will come to your server. But it maybe a neat way to do it as you would only do the aerial tiles.

This raises another issue - hybrid mode. If you didn't know VE has 3 sets of tiles Aerial, Road and Hybrid. By simply updating the Aerial tiles you will not update the Hybrid - they are generated seperatly. You start to see why I'm interested in other ideas.

The best way to start is to use a layer, it will have a delayed loading but in a way that is kind of cool in that it shows your town has updated its imagry, apart from the map cruncher demo I think you would be the first to do it in the world with VE - please correct me if I am wrong.

Oh and for reference here are the links to the layers we did in Australia:

http://www.lookupandsmile.com.au/what_map.aspx ID=pi1mE2gaz3

http://www.lookupandsmile.com.au/what_map.aspx ID=be|jD2qah0

http://www.lookupandsmile.com.au/what_map.aspx ID=xj5|DqzhdU

(the 2nd one is the best as the tide changes!)

John.