Displaying an Animation as a Wire Mesh

The same series of images can be displayed as different types of animations. For example, each frame of the animation could be displayed as a SURFACE plot.

Create a new array to hold the heartbeat data:

S=REBIN(HEART_BINARY.H,32,32,16)

S now holds 32 byte by 32 byte versions of the heartbeat images. SURFACE plots are often more legible when made from a resized version of the dataset with fewer data points in it.

Display the first image in S, as a wire-mesh surface by entering:

SURFACE,S[*,*,0]

Figure 11-2: Surface visualization of heartbeat data

Figure 11-2: Surface visualization of heartbeat data

Now create a whole series of SURFACE plots, one for each image in the original dataset.

To do this, first create a three-dimensional array to hold all of the images by entering:

FRAMES=BYTARR(300,300,16)

The variable frames will hold sixteen, 300 by 300 byte images.

Now create a 300 by 300 pixel window in which to display the images:

WINDOW,1,TITLE='IDL Animation',xsize=300,ysize=300

A blank IDL Animation screen will appear.

The next command will draw each frame of the animation. A SURFACE plot is drawn in the window and then the TVRD function is used to read the image from the plotting window into the frames array. The FOR loop is used to increment the array indices. The lines which follow are actually a single IDL command. The dollar sign ($) works as a continuation character in IDL and the ampersand (&) allows multiple commands in the same line.

Enter:

FOR I=0,15 DO BEGIN SURFACE,S[*,*,i],ZRANGE=[0,250]$
   & FRAMES[0,0,i]=TVRD()&END

You should see a series of SURFACE plots being drawn in the animation window, as shown in below. The ZRANGE keyword is used to keep the "height" axis the same for each plot.

Now display the new images in series by entering:

FOR I=0,15 DO TV,FRAMES[*,*,i]

Figure 11-3: One of the SURFACE plots of the animation window

Figure 11-3: One of the SURFACE plots of the animation window