When we first set out to create Google Earth tours for the One Ocean site, it was hard to find a comprehensive guide on creating them. There was lots of information on how to do a very basic narrated tour, but we had some bigger requirements than that. Working with filmmakers was a double edged sword: they knew exactly how they wanted to script it, but they also had some high expectations.
In the next two blog posts, I’d like to show you how we went from a very trial-and-error approach to something fairly structured which we were able to reproduce for the five ocean tours currently on One Ocean Online. First, the materials we started with:
- The script – this outlined the points in the narration where we would focus on each location, and whether to show pictures and videos.
- The pictures – we’re using some great stock photography which we’ve resized to 300 x 400.
- The videos – these are housed on CBC’s servers, and are loaded through a Flash file.
- The narration – these are a series of MP3 files spoken by Sarika Cullis-Suzuki.
Note: if you’re unfamiliar with some of the terms in this article, I recommend starting with Google Earth for Dummies, which provides a great introduction to the topic.
Part 1 – Setting up the tour
First we will set up all the points in the tour (aka placemarks). Make sure you’ve set each placemark with the angle you want, as they are difficult to change later on. Remember, you’re not limited to just a top down view, so try to choose something interesting. eg:
- Mountains nearby? Tilt the camera so they appear in the background.
- There’s not much to see underwater, but it’s a cool effect when you swoop down under the surface.
- Aiming your placemark at the horizon means as the camera goes to that point, it will fly there as an airplane would.
- Pointing up at the sky could make a nice backdrop for photos or videos.
Tip: If you’d like to adjust a placemark you’ve already made, right-click the placemark and click snapshot view. This will take the coordinates, bearing, and tilt of the current view and apply it to the placemark.
Okay, let’s set up our ‘project’ which will contain all our placemarks, overlays (photos), and the tour:
- In the Places box on the left side of the screen, right-click My Places and click Add | Folder.
- Enter a Name for your project (eg: pollution)
- Create three additional folders within your project called Placemarks, Overlays, and Tours.
- Create your placemarks by finding an location on the globe, adjusting the tilt (hold the ctrl key while dragging the mouse) then right-click on your Placemarks folder and click Add | Placemark.
It’s not necessary to create those three folders in your project, but I find it’s a good way to organize your assets. Now that we’ve got everything organized and our placemarks created, we’ll begin creating our tour.
Timing Your Audio
Since we were working with prerecorded MP3 files, this was a bit tougher than just recording the narration as we went — this is because we had to make sure we left enough time for each narration to finish before hopping to the next placemark. Now, it’s impossible to get the timing 100% correct, but a useful trick is to have all the MP3s loaded up in an audio player and play these while you’re recording your tour. This way, you’ll know when each narration is finished and to hop to the next placemark in the tour. We’ll fix the timing up later on, so don’t worry about getting it perfect.
Okay, so once you’ve got your narration MP3s queued up in your audio player (I like to use foobar), it’s time to start recording the tour.
- Right-click your Tours folder and click Add | Tour.
- A small window will appear near the globe.
- Double-click the first placemark in your tour. This is your starting point.
- Click the red circle to begin recording.
- Play the first narration MP3 in your audio player.
- Hop to the different placemarks you want to display during this narration, or simply wait until the narration has finished.
- Repeat steps 5 and 6 for each narration MP3.
So what have we done here? We’ve created a tour which is somewhat synchronized to our narration audio files. Unfortunately, we can’t simply embed the audio files through Google Earth; we’ll need to add them directly into our project’s KML file. In fact, we won’t be editing our tour using Google Earth anymore after this point. We will be editing the KML file directly. No, it’s not fun, and I welcome any suggestions you may have on simplifying this process :)
Right-click your project folder and click Save Place As… and save it as a KML file on your hard drive. Now you can make changes to the KML file (which is a type of XML file) using your text editor of choice (I like Aptana Studio because it’s free). Take a look at my KML file for the pollution tour.
Aside: After having different versions of these tours floating around, we decided to track our changes with Subversion. This allowed us to keep everything in one central repository and to keep track of any changes that were made to the KML file. This isn’t required for making Google Earth tours, but it is essential when you have more than one person working on these.
In part 2 of this series, we look at how to:
- work with KML files in a sane way,
- play our MP3 files
- adjust timing
- display photo overlays
- display video overlays