The CPU performance of our SPARC based
workstations runs from 12.5 to 22 MIPS and from
1.2 to 3.8 double precision MFLOPS.
3.2. Image acquisition
DIPS II allows a variety of options for image
acquisition:
• Direct acquisition with CCD cameras through
the DATACUBE system in mono and stereo
mode.
• Direct acquisition with CCD cameras via video
tape recorders and a PC-AT based MATROX
MVP-AT board. So far a maximum
configuration of three CCD cameras and
simultaneous recording on three video-tape
recorders has been used in projects like turbulent
flow measurements and biomechanical human
movement studies (see section 4 and
Papantoniou, Maas, 1990; Baltsavias,
Stallmann, 1990).
Intermediate video-tape storage in analogue
form and subsequent digitisation is also possi
ble with data coming from a JVC GR-S77E (S-
VHS) video camera.
• Image conversion by using CCD cameras as
digitising devices at the analytical plotters
WILD AC1 and PRIME WILD S9-AP (Wilkins,
1990a). Each of these analytical plotters is
retrofitted with mounts which accept CCD
cameras at both stages. For the AC1 acquisition
the DATACUBE system is used, while for the
S9-AP acquisition new, separate framegrabbing
devices are planned for future installation.
• Direct acquisition by means of a still video
camera CANON RC701 and an associated video
recorder (Novak, 1988). This system will soon
be replaced by a camera of higher resolution.
33. Image display and image handling
The image display is based on the Sun Pixrect
functions for maximum performance and is
embedded in the Sun View window system. The
framebuffers supported are the 8 bit deep
framebuffer as used on most workstations as well
as the 10 bit deep framebuffer of the Sun-3/110 and
Sun-3/E workstations. The Sun Workstations use a
framebuffer of 1152 x 900 pixels, providing for the
display of several small (512 x 512) or one large
image within a window. The typical memory size
of our workstations varies from 8 to 32 MB. Very
large images thus require that the operating system
places part of the data through the paging/swapping
mechanism in the “swap space” on disk and reloads
it to memory when needed. When using a “virtual
memory technique” for handling large images the