Instructions for making colour movies (colour density plots) with rgb:

1. First, prepare a data file in the following format, using XDR (External Data
Representation, a portable binary data representation). 

C++ users: see http://www.math.ualberta.ca/~bowman/xstream.html

Each frame has the following format:
Fields				Description

Nz Ny Nx	Dimensions of the data. Use N1=1 to display a single
	two-dimensional cross-section. Cross-sections are displayed
	consecutively, separated by a black band. The data is
	stored sequentially, with the last index varying most rapidly.

data[Nz][Ny][Nx]       Nz*Ny*Nx float values

Multiple frames are generated by concatenating single frames together into
the same file.

2. Then run rgb on this file.  This converts the data values to a movie file
using a rainbow spectrum as a palette.  It accesses other programs, most of
which are part of the ImageMagick package (from
ftp://ftp.wizards.dupont.com/pub). For final production, I recommend the -m
option, which uses the "mpeg" encoder to produce a highly compressed .mpg
movie file.
Alternatively, one can make an animated GIF with commands like
rgb -extract gif C
convert -loop 10 -delay 50 C*.gif animation.gif


From the online-help:

RGB version 1.25 [(C) John C. Bowman 2005]
Usage: rgb [options] file1 [file2 ...]

Options: 
-b               single-byte (unsigned char instead of float) input
-f               use a floating scale for each frame
-g               produce grey-scale output
-h               help
-i               invert vertical axis (y-origin at bottom)
-m               generate mpeg (.mpg) file
-p               preserve temporary output files
-r               remote X-server (substitute Postscript fonts)
-v               verbose output
-l               label frames with file names and values
-label text      label frames with text and values
-o name          output file name (prefix only)
-F               use a floating scale for each section
-x mag           overall magnification factor
-H hmag          horizontal magnification factor
-V vmag          vertical magnification factor
-B begin         first frame to process
-E end           last frame to process
-L lower         last section to process
-O option        option to pass to convert or montage
-U upper         first section to process
-S skip          interval between processed frames
-X xsize         explicit horizontal size
-Y ysize         explicit vertical size
-Z zsize         explicit number of sections/frame
-backwards       size information is stored backwards
-pointsize size  point size to use with labels
-avgx points     number of data points per pixel in x direction [default 1]
-avgy points     number of data points per pixel in y direction [default 1]
-symmetric       make color palette symmetric about zero (if possible)
-bar n           thickess of palette bar in pixels
-band n          thickess of palette separator band in pixels
-bandcolor n     color of palette separator band
-extract format  extract individual images as tiff, gif, etc.
-crop geometry   crop to specified X geometry (specify 0 to invoke xv)
-rescale         rescale palette to cropped region
-xrange x1,x2    limit x-range to [x1,x2]
-yrange y1,y2    limit y-range to [y1,y2]
-zrange z1,z2    limit z-range to [z1,z1]
-minimum min     minimum threshold
-maximum max     maximum threshold
-vector          plot 2 components using spectral intensity gradients
-vector2         plot 2 components as red--blue values
-vector3         plot 3 components as red--green--blue values
-reverse         reverse palette direction
-ncolors n       maximum number of colors to generate (default 65536)
-view            view single frame with xv
-background n    background color
-gradient        apply intensity gradient to spectral palettes
-damp            apply color intensity damping
-2               double spectral palettes and apply intensity gradient

Standard Color Palettes:
-bwrainbow       black+rainbow+white spectrum [default]
-rainbow         rainbow spectrum
-brainbow        black+rainbow spectrum
-wrainbow        rainbow+white spectrum
-wheel           full color wheel
-rgreyb          red-grey-blue
-red             red scale
-green           green scale
-blue            blue scale
-yellow          yellow scale
-cyan            cyan scale
-magenta         magenta scale
-redblue         red-blue scale
-redgreen        red-green scale
-greenblue       green-blue scale

General Linear Color Palette:
-const r,g,b     starting color codes (each between 0.0 and 1.0)
-rate r,g,b      color increase rate (each between -1.0 and 1.0)

Transforms:
-identity        no transformation [default]
-circle          circle
-torus           projected torus (3D)

3D Options:
-Rfactor factor  viewpoint distance factor [default 2]
-Theta radians   angle to rotate about X axis [default 0.9]
-Phi radians     angle to rotate about Z axis [default 0.9]
-cutoff radians  cutoff for toroidal angle [default 0]
-yxaspect ratio  Y/X aspect ratio [default 1]
-zxaspect ratio  Z/X aspect ratio [default 1]
