Google Earth it!

Using GeoJavascript, you can very easily collect a pair of coordinates and launch Google Earth to view the location. This is in addition to the functionality that is already in place called, "Google Map it!". Here's what you do...

1. Create a folder-level .js file in your ACROBAT_INSTALL/JavaScripts folder and copy the following code in to it. Download the file from here.

2. Open up your GeoPDF file and select the GeoTool, then right-click and select the TerraGo context menu.
3. Choose the newly created Google Earth it! option.

If the stars are aligned properly, Google Earth should open and it should zoom to the location you had selected with the GeoTool.

** Please note, if Google Earth is not your default 'KML' viewer on your Windows system, it will open the app that is associated with 'KML' files.

Please refer to this earlier article with more information on how to do this and thanks again to JB Freels for putting all this together. There is a LOT of cool stuff we can do with GeoJavascript. More to come!

Why GeoPDF?

The question "Why GeoPDF?" has come up a lot lately primarily because Adobe released their GeoSpatial PDF format. I would like to share what I know about this format and possibly clear the air about the question at hand...

What is GeoPDF? GeoPDF is a geospatial extension to the Adobe PDF file format, from TerraGo Technologies. It is used to present GIS and mapping data in a standard Adobe Systems PDF. This extension adds a coordinate transformation matrix and other metadata to allow transformation of PDF coordinates to a projected Cartesian coordinate system. GeoPDFs often include other advanced PDF features such as layers and object data which can add significant GIS functionality to the file, particularly when used with the TerraGo Technologies plugin to Adobe Reader.

GeoPDF is still a PDF which means that ANYONE with Adobe Acrobat Reader can view your map data (look in the link to see that whoever added the Adobe Acrobat definition in Wikipedia, chose to display a graphic of a map!). It's true that you must download the GeoPDF Toolbar to gain access to the GIS functionality but wouldn't you expect to do this in most applications to access the intended functionality? I often write about Google Earth, Photosynth, and a variety of other GIS/Visualization Tools all of which require a download of some kind! A key benefit of the GeoPDF Toolbar is that you get GPS Tracking functionality.

What information can I include in my GeoPDF? There is quite a bit of data that can be added! For example, let's say that I am using Map2PDF for ArcGIS and in my map layout I have a raster image as a background, a shapefile for my streets data, an ArcSDE layer for parcel data and finally I create custom symbology and labels for each layer. I can export each one of these features to GeoPDF (with hyperlinks and annotations) in a separate layer in the final map. How is attribute data maintained? The GeoPDF export creates the equivalent for attribute data which is called Object Data. By creating object data in your output map, which is optional by the way, you can search for all the attribute data just as if it were in its original form in ArcGIS. With the ability to Zoom To a selected feature, you have a pretty powerful geo-search tool.

Map2PDF for Acrobat add-ons included GeoMark tools that allow users to add shapes and standard or custom stamps with comments. MapAssembler lets users combine maps and grids to create Map Books. Map2PDF for Acrobat lets users turn any PDF-based map into a georegistered map - a GeoPDF file - simply by entering two coordinates. But, there's much more to Map2PDF for Acrobat than that.

Map Book, Map Book, Map Book!!! What the heck is a Map Book? A Map Book is a a set of GeoPDFs that are indexed together to create a seamless interaction between the end user and the data. Check out the Map Book that I posted earlier this year! I called it Fun with Hyperlinked Data. I did go a little overboard with the Lightbox2 javascript but it does a great job in helping to tell the story! In a Map Book series, there is also the ability to search for features stored in an external database and create custom functionality through GeoJavascript.

Map2PDF for Raster: I have seen 6 gigabytes of raster data compressed down to a 400 megabyte GeoPDF. Wow! That is an impressive compression ratio! I mentioned earlier that we can create layered PDFs which means that with our raster data, we can see a base layer as an RGB image but then we can add additional bands to be turned on and off as needed. For Landsat ETM+ data we can create a base map with bands 1, 2 and 3 then add additional bands and assign a particular color to each one. Because they are treated as seperate layers, you have the ability to turn them on and off dynamically. Imagine what you can do with low-resolution multispectral data like AVHRR? MODIS/ASTER? Click here to download some example data.

Things to look forward to: Mobile apps, Enhanced GeoJavascript, Advanced GPS Track Manager, leveraging Acrobat 9.0 functionality like Adobe AIR and much more...