The People of RSI Demo

We have included the pictures of the employees of Research Systems so
that you can see the people who develop and support IDL.  This demo
also illustrates image warping, morphing (the gradual changing of one
image to another), and compression using IDL.

The pictures are stored in JPEG compressed image format, which is
fully supported by IDL.  Each 192 by 192 image containing 36K bytes,
is stored using JPEG in less than 6K bytes, resulting in approximately
6 to 1 compression.

To experiment with image warping, first display a picture, then click
the "Warping" button.  The warping control box should become visible
on the right side of the demo widget.

Control or "tie" points are used to specify how the image is to be
warped.  Each control point in the original image is transformed to a
designated point in the "warped" output image.

To make a control point: with the cursor over the control point (CP)
in the original image, depress the left mouse button and drag the
cursor to the control point's position in the destination image.  Then
release the button.  IDL will draw an arrow with the base at the CP's
original position, and the head at the "warped" position.  At least
three CPs must be defined to warp an image.  Up to 100 CPs may be
defined.

To make a CP with the same position in both the original and output
image: simply click the mouse left button at that point.  This has the
effect of fixing that point at the same location in both images.

Note: the output image is only defined over the convex hull of the
control points.  To include the entire image, use the "Mark Corners"
button.

			WARP CONTROL BUTTONS

Undo:  Removes the most recently defined control point.  

Mark Corners: Places four control points in the corners of the image.
	This fixes the corners of the output image to the same
	positions.

			VIEWS

Warped Image:  if three or more control points are defined, the warped
	image is displayed.

Original Image:  displays the original image and the arrows connecting
	the CPs in the original and warped images.

X Surface: shows a mesh representation of the warping function in the
	X dimension.

Y Surface: shows a mesh representation of the warping function in the
	Y dimension.

Reset:  Displays the original image and clears the control points.