Date: Wed Nov 16 13:04:20 PST 1994

  Once you have managed to read individual frames from a
  movie file (see above), you have several options for
  writing the still frames to an image file.

  There is an image library, libimage.a, which supports
  reading and writing the Silicon Graphics RGB file format.
  Sample programs for using this library appear in the
  4Dgifts subsystem.

  Also, you can purchase the optional SGI ImageVision
  Library.  ImageVision supports output to several image file
  formats, including SGI, TIFF, JFIF, and its own proprietary
  FIT format.  C++ developers can add their own file
  formats.  ImageVision also provides several powerful
  operators for converting, procesing, and displaying image
  data, and also provides hardware acceleration on SGI
  platforms which support it.  Contact your SGI sales office
  for more details (see above for details about where to
  call).

  Finally, make sure you've installed the Movie Library
  example programs.  They contain a program called
  editmovie.c which writes still frames to image files, using
  ImageVision to write the data to disk.