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Offline Windows app to plot GPX data on aerial imagery
BenC
Hi,

I am trying to solve a seemingly simple problem, but am having an unreasonable amount of trouble with it, and I am hoping for your assistance.

I am riding an offroad rally in North Africa and would love to be able to plot each days route (from a GPX file) on high resolution sattelite/aerial images on my Windows laptop, but I will not have any internet access. I would love to use Google/Bing imagery, but would also be happy to use Landsat data instead.

So a few questions:
- What Windows application is suitable for this? Given that it must be able to use offline imagery data.
- Are there any recommended sources of data other than Landsat that I should be looking at? Area of interest is Morocco, Mauritania and Senegal, and a very large area (probably equivalent to 50% of Morocco to give an idea of scale).

I am also having trouble with the mechanics of getting the imagery data converted/formatted/georeferenced correctly to be displayed in the various viewer programs I've tried. Any suggestions here?

I understand these may be some basic questions, so links to guides/FAQs/tutorials are valued too.
Thanks
Ben
Boyd
You could have a look at mobile atlas creator (MOBAC). It downloads tiles from WMS (web mapping service) servers. It's a very cool open source program that can create files in many different formats, I use it to make atlases for iOS and Android devices from maps that I create myself. I'm not sure what Windows software would work with the files it creates, you'd need to research that… or maybe you would find a tablet a better solution than a laptop?

The program is provided with a built-in menu of map sources from various places where you can legally download imagery. It originally supported Google and some other well known sources, but the authors had to remove it because Google does not allow bulk downloads of their imagery.

No idea what would be a good source in your area. You can do some web searches with the name of your area of interest with terms like WMS, MOBAC, etc. For example

north africa wms download

You can add any WMS servers that you find as custom mapsources in MOBAC, but this gets a bit technical and confusing…

http://mobac.sourceforge.net
Ken in Regina
A couple of possibilities come to mind.

Garmin Basecamp supports GPX import and has a commercial imagery product called Birdseye Imagery. The quality of the imagery is, from reports I've read, variable. Basecamp is free. The imagery is not. Downloading the necessary imagery in advance would give you an offline solution, if the imagery for the necessary areas is any good. I don't know if there is any way to preview the imagery.

Google Earth allows you to cache a certain amount of imagery so you can use it offline. I think the cache should be large enough for your purposes. This has the advantage of allowing you to preview the imagery. I don't know if there is any way to manually save/restore the cache in case you manage to inadvertently flush or overwrite it.

...ken...
BenC
Thanks gents, after speaking to some friends I got going with Basecamp and Birdseye today. I already use Basecamp so that gave me a bit of a head start. There have been a few hurdles, but things now looks promising. I think I will have at least reasonable data to take with me.

In the long run it'd be a good idea to learn more about how to build up my own data from various sources, but unfortunately I am short of time right now.

I'd also read about caching Google Earth data, but read that recent versions of GE won't run at all without internet access. And also automating the caching of the right area at the right resolution is likely beyond my skills.
Ken in Regina
Hey Ben, I'm glad you are finding something that will work. What will you be riding in the rally?

...ken... <BMW F650GS>
BenC
OK, just a bit of a rundown of what I have done in case anyone ends up in the same situation as me.

The main challenge is that Birdseye is designed to load aerial images to a compatible GPS unit, not just view them in Basecamp. So there are some hurdles if you, like me, use a good old 276c.

Firstly open Basecamp and there is a Birdseye menu with an option "Download Birdseye imagery...". Good so far, but Basecamp then searches for a compatible GPS attached to the computer. If you don't have one of them you need to fool it by loading the .XML file hosted here (need to sign up to download it) into a folder named "Garmin" in the root of a USB key, so that it looks like a compatible Garmin unit. Then you can choose the Birdseye product (I used Sattelite Imagery Subscription V2).

Birdseye is a subscription service costing about $40 a year. I'd happliy pay that, but to purchase it online you MUST have a compatible GPS unit registered to you Garmin account. I don't, but you can use the demo version and a workaround. The demo version allows you to download only one aerial image (problematic, but can be fixed as described below), and will not allow you to transfer the images to a GPS (no issue for me).

Now to use the demo just click "Continue" and you can then select the area and quality you want to download. There are limits to the size of each download:
Standard quality: 5000 tiles, 57Mb, roughly 60km x 60km
High: 107Mb, 20 x 20km
Highest: 76Mb, 7km x 7km

Hit download and things get going. A single .JNX file will be downloaded, containing all the sattelite data selected. I find it takes about half an hour to download each 57Mb chunk of Standard data. Even underway you can see the data tiles pop up in Basecamp. And now you have some sattelite imagery over which you can plot routes and waypoints etc.

Now, using the demo version, if you try to download another area of sattelite imagery then Basecamp will warn you that the previous image will be deleted. This is only half true. You won't be able to see the imagery in Basecamp any more, but the actual .JNX data file will not be deleted until you quit Basecamp.

So what you need to do is as you go, or at the very least before you quit Basecamp, is to copy all the .JNX files out to another location. By default the Birdseye .JNX files are downloaded to:
%APPDATA%\Garmin\BaseCamp\JnxFiles

For me, using Windows 8.1 I found them in the "Roaming" directory. In my case this was:
C:\Users\bc\AppData\Roaming\Garmin\BaseCamp\JnxFiles

If you want to store them elsewhere, on an external drive, or a simpler path you can set up a new database in Basecamp (Google how to do that).

So now you can build up a depot of .JNX files covering the area you are interested in. Though it is very labour intensive for large areas or high quality. To then view all the images in Basecamp again takes a trick too. I copied them to a "\Garmin\Birdseye" directory on my USB key that was made to look like a Garmin GPS. Then once this is recognised in Basecamp it will show that it contains all the Birdseye data you've downloaded. This can then be copied into your Basecamp library and used as you see fit. However be warned, if you download more Birdseye images you will no longer be able to see this data in Basecamp, it will need to be reloaded.

So that is what I've learnt from extensive Googling over the last couple of days. Hopefully it is helpful to someone else one day.

Ben

And Ken, I'll be riding a Honda XR650R. The last serious bike built
Boyd
Glad that you found a solution that meets your needs. However, you have posted instructions on how to download Garmin imagery that you are not legally entitled to by using a file from a hacker site where illegal cracks of commercial software are posted and discussed.

We don't usually discuss way to crack Garmin's software in the forums here…
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