Google Earth Lessons

An Educational Resource for Teachers

 

Appearing, Live…

Nifty Tricks with Live Images in Placemarks!

A really cool thing you can do with your placemarks is to include live pictures! Students will stare in amazement, wonderment and gleams of understanding will show in their eyes when you show how on the other side of the world it is night, or if you visit someplace where the sun is just rising or setting, or the weather has taken a turn for the worse (this last works great with the Cloud Cover Overlay used in conjunction with a Live Cam!)

It is extremely easy to do, taking only a bit of web surfing and a single line of html code.

There are quite a few placemark collections already available that have compiled web cams world-wide, but they include just a handful of the total number of webcams out there. One of the better ones includes 185 World Web Cams.

But there is a lot more you can do with Live Cams than just link them!

A Live icon

The three step process in brief is:

  1. Find a webcam image on the web and copy its address, either the address of the image or the address to the site where it is.
  2. Use the tag <img src="CameraAddressHere"> in the Description box of your Placemark to display certain kinds of webcams directly inside the placemark, being sure to credit the site whose image you are using. To link to a website that contains the live picture, simply copy the URL into your placemark.
  3. To have the icon be a Live Camera image, edit your placemark with the image's URL as the icon location.

Not only can you include the webcam in the icon, but in the balloon that pops up as well!

Hazecam Balloon

Now for the details…

Step 1. Collecting a Webcam Address

Disclaimer #1: There may be copyright issues related to using a live webcam image in your placemark depending on the host site. Some websites put up live cams to draw traffic to their website, others have them for tourism promotion reasons, others are operated by government agencies with public funding for educational purposes, others still include them because the site operator lives in a neat place and just wants to share the view out their office window because it is a fun, cool thing to do. Use your professional opinion, personal discretion and moral compass when determining which webcams to include and how to cite them, especially since you may not be able to read the language of the host site to determine usage restrictions. Your target audience may also play a role in your final determination.

Disclaimer #2: Since you will be working with images on the internet that are beyond your control there is a possibility that the links will break and the images no longer function. Be sure to test your work just prior to presenting it.

Where to Look for Images:

Finding a good webcam is the hard part, especially for under-developed countries. Some good starting places for your webcam search include www.earthcam.com which has a nice listing of cameras broken down by time zone and very few ads. It is the site I feel safe sending my students to when I have them research webcams for geography related lessons. There are many other places though.  Just do a Google search for ‘Web Cam Directory’.

Another favorite besides earthcam.com is http://www.leonardsworlds.com/camera.html. It is pretty much a safe site, but some of the ads contain bikini girls, that sort of thing. Should you find another good site for webcams, please feel free to add it to the GELessons.com Link Bucket!

Part of the reason I mention safety is because some webcam collections show nudity or other inappropriate things which students and parents might be offended by. It is extremely risky to send students out webcam surfing to places other than those you feel meet your community’s standards for decency and which you have selected by hand, hence the advantage of placing webcams in placemarks.

What to Look For:

When you are searching for a live webcam images to include in your placemarks what you are looking for are camera images that are called as .jpg images. Webcam technology has come a long way in a very short time and the choices for images are quite sophisticated, including streaming video, Java enabled control modes and on and on. If your goal is to have a live image displayed within your placemark what you will need is a good old-fashioned jpg upload since Google Earth does not support video or Java or anything fancy like that.

How Webcams Work:

It helps if you understand how webcams work. There are many software programs available for putting live camera images up on the web. They fall into essentially three categories.

The first category are the kind that you will have the most success using an image from. They are lower tech, less expensive, fairly common and work by capturing an image (taking a picture with the camera attached to a computer) and then sending that picture via ftp to the web server, putting it in the right folder on a predetermined schedule, where it becomes available to you. Sometimes the schedule is a very short time, such at 15 seconds, others are set on a longer schedule to conserve resources and might be uploaded once an hour or once a day. Once the image is uploaded it overwrites the existing picture file and when you call it in your placemark you get the last picture that was uploaded. This kind is very easy to set up and use from a webmaster’s standpoint because you create your simple webpage once and forget about it, the software takes care of the rest.

The second category is a little more sophisticated but works in the same way as the previous kind, the difference is that when the software uploads the image it is named with a time stamp dynamically so that older versions can be archived (for example it might name the picture: 041006_1232.jpg). The web page you visit is also created at the same time with the updated image name, then served to you along with the latest picture. Since the image is named something new every minute or hour or whatever, you most likely won’t be able to use it since it would put only the picture that you copied the location of when you created your placemark. Depending on the site, you may be able to work around the problem by hacking the source code of the web page the image is displayed in. This is tricky and Google Earth does not support a lot of fancy coding in placemarks so it will be hit and more frequently miss.

The third category is the most expensive and sophisticated and you will not be able to use at all inside your placemark. What happens with the third kind of webcam software is that there is a constant chatter between the camera and the web server where graphic information is sent ‘on-demand’ which is how you can have streaming video, constant updates, etc. This dynamic transfer of data is beyond Google Earth’s limited ability to understand in placemarks but when linked and viewed in a web browser can be quite exciting to students.

Using the images you find:

Once you have found a good candidate for inclusion in your placemark you need to copy the address of the picture, and the site.

To copy the address of a live jpg, control click (right-click) on the webcamimage in your web browser, pull down to ‘Copy Image Location’ and away you go!

With Internet Explorer
IE is fussy

With Mozilla Firefox
FireFox is Better

You can either paste the image location into a text document for later use or directly into your placemark’s Description window.

Comparing URLs

Below are two examples of some of the types of URL you are likely to see:

Won’t Work
Site URL: http://www.oberstdorf.de/index.shtml?webcams
Resulting Image URL: http://www.oberstdorf.de/cgi-bin/syndication/se_syndication_webcam.pl?cam=1&key=obXcZrwii7EDk&size=&random= <--Note the strangeness and lack of .jpg ending!
Example placemark: Bad Image URL.kmz

Will Work
Site URL: http://www.hazecam.net/acadia.html
Resulting Image URL: http://www.hazecam.net/images/photos-main/ACADIA.JPG <--Note the .jpg ending & no time stamped name!
Example placemark: HazeCam.kmz

Once you found a good candidate it is time for Step 2.

Step 2 – Including Live Cams in Placemarks.

As briefly discussed in step 1, there are two ways to call a live cam in a Google Earth placemark.

The first, simplest and least likely way to cause copyright violations is to find a web page with a webcam, copy its address, and paste the address into the description box of your placemark. This will allow the student or user to click on the link and view the camera in a web browser. You can either copy the entire URL, such as http://www.gelessons.com, or an abbreviated URL such as www.gelessons.com into your placemark. Abbreviated URL’s will only work as clickable links if they are preceded by www unless you hand code the HTML into the placemark to make it an active link. (EX: <a href="http://gelessons.com">gelessons.com</A>

The disadvantage is that with the opening of a web browser, either inside or outside of Google Earth, you no longer control the information the student sees.

The second way is to put the image directly inside the placemark so that when the student clicks on it (or you click on it) they see the picture and can make the connection between the abstraction of Google Earth’s representation of reality and what a place actually looks like right now.

To include a live image (or any image for that matter) you need to use HTML code. The code is below for you to copy:

<img src="PICTURE URL HERE">

Please note the quotation marks before and after the PICTURE URL. Some web page creators do not put in the quotation marks but Google Earth requires them. You will, of course, need to substitue the URL (http:// address) of the image that you copied for the PICTURE URL HERE part.

A completed example:

<img src="http://www.hazecam.net/images/photos-main/ACADIA.JPG">

For most workable webcam images this will be enough to get you by. There will be times, however, when you will want or need to be more specific in your placemark. Not only that, but to get the appearance just the way you want, you will need to add other HTML as well.

You can do this either by hand or by using an HTML editor such as Nvu, Dreamweaver or in a pinch, FrontPage. I personally do not like FrontPage because it tends to put in too much extraneous HTML code which can cause problems in placemarks.

One big reason you would want to ‘custom code’ the placemark HTML is because the picture is too big to fit in the placemark window and will create scroll bars which can be distracting. To control the size of the image you will need to use the height and width HTML in your <img src="…"> tag. For Example:

<img src="http://www.hazecam.net/images/photos-main/ACADIA.JPG" width="250" height="150">

Again, notice the quotation marks. To find out the dimensions of the initial webcam image, you will need to copy the image to your computer, open it up in a graphics program such as Irfanview, Photoshop or GraphicConvertor, find out it’s dimensions and then divide the dimensions by the same number. For instance if you get information on the picture and it’s real size is 1500x1200, you would want to cut it down proportionally by a set factor, such as 3, ending up with 500x400. Be careful with your calculations or you might end up with a messed up picture as in the example placemark.

Other HTML codes to keep handy include:

<CENTER> <img src="IMAGEURL"> </CENTER>

to center the picture in the middle of the placemark.

<BR> is a line break to add spaces above or below the picture to make the text more readable.  

<a href="WEBSITEURL"> <img src="IMAGEURL"> </a>Makes the picture into a clickable link, opening a web page you selected in the web browser window.

Super Prettifyin' your Placemark:

Creating a Live Icon for your placemark is a neat way to dispay a live camera's image without having Google Earth's display cluttered by a large balloon. To create a live icon, simply copy the URL into the Placemark's icon field.

cutom icon adding

 

Floating...

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Well, we hope you have fun! Webcams are so cool, and with Google Earth they get even cooler!!

Show off your best Live Cam Placemarks by tossing them in the GELessons.com KMZ bucket!