Part 5—Animate GOES Images Using ImageJ
Step 1 Launch ImageJ and Open GOES Images
- Launch ImageJ by double-clicking its icon on your desktop (Mac or PC) or by clicking the icon in the dock (Mac) or the Start menu (PC).
- Choose File > Import > Image Sequence..., browse to the folder where the downloaded GOES images are saved. Click Choose. This will open the GOES images in order, from earliest to latest.
- The images will appear in a single window (a "stack") with an animation control bar along the bottom. Each image in the stack is referred to as a "slice." Save the stack, and then slide the animation control bar to animate the GOES images.
Choose File > Open and select the images one by one. Each time you open a new GOES image in ImageJ, it will appear on top of and slightly lower than the previous image. Be sure to open the GOES images in order, from earliest to latest. In this case, you will need to convert the images to a stack before you can animate them. Choose Image > Stacks > Convert Images to Stack.
Once you have opened the images, choose Image > Stacks > Convert Images to Stack. The images will appear in a single window (a "stack") with an animation control bar along the bottom. Each image in the stack is referred to as a "slice". Save the stack, and then slide the animation control bar to animate the GOES images.
Step 2 Animate the GOES Images in ImageJ
To get an overview of a few hours worth of water vapor changes, you will animate the stack of 6 satellite images to make a mini movie.
- In ImageJ, start the animation by choosing Image > Stacks > Tools > Start Animation.
- Image > Stacks > Tools > Stop Animation stops the animation.
- Use Animation Options under the same pulldown menu as the start and stop animation, to control the speed, or use the "." and "," keys on your keyboard to move forward or backward one frame at a time.
- You could also choose to have the stack tools (see below for screen shot of stack tools) show up in the ImageJ toolbar. This will give you a controller for your animation.
- Watch the movie carefully enough to get a sense of the changes in water vapor over the chosen time period. You can look at the file names in the upper-left corner of the window to see what date is being displayed. Consider the following questions:
- What happens to water vapor over a day, week or month? It moves across the country.
- What month would you estimate has the most water vapor each year? Summer time because there is more heat energy from the sun.
- What happens to water vapor over a day, week or month?