42
J. Jensen
how many millions-of-instructions-per-second (MIPS) it can process, e.g. 450
MIPS.
Personal computers (16- to 32-bit CPUs) are routinely used to perform digital
image processing and GIS analysis. These complex-instruction-set-computers
(CISC) have CPUs with 16- to 32-bit registers (word size) that compute integer
arithmetic expressions at greater clock speeds and process significantly more
MIPS than their 8-bit predecessors. 16-bit CPUs can process two 8-bit bytes at a
time while 32-bit CPUs can process four bytes at a time. Table 3.1 documents the
historical development of the Intel family of CPUs used in IBM compatible personal computers. Scientists often populate laboratories with PC-based digital image processing systems because the hardware and software are relatively inexpensive per unit and hardware maintenance is low. Typical personal computers cost
<$3,000 with 24-bits per pixel of image processor memory (with a 16.7 million
color lookup table) and a high resolution color monitor.
Table 3.1. Historical development of the Intel family of CPUs used in numerous IBM compatible personal computers (Freedman, 1995; Spooner, 1999)
CPU (word size)
Clock Speed (Mhz)
MIPS
8088 (16)
5
0.33
8086 (16)
5 - 10
0.33 - 0.66
286 (16)
6-12
I.2 - 2.4
386DX (32)
16 -40
6 - 15
486DX (32)
25 - 100
20 - 80
Pentium I
60- 200
100 - 250
Pentium II
300- 400
300 - 400
Pentium III Celeron
>466
>450
Computer Workstations (2:32-bit CPUs) usually consist of a 32 to 64-bit reducedinstruction-set-computer (RISC) that can address substantially more random access memory than personal computers. The RISC chip is faster than the traditional
CISC and is designed and built more economically (Freedman, 1995). Workstations also usually have a bank of 8- or 24-bit image processing memory and a very
high resolution color monitor (Denning, 1993). Figure 3.1 summarizes the components found in a typical digital image processing workstation laboratory. RISe
workstations can function independently or be networked to a file-server as
shown. Some RISC workstations have multiple CPUs that allow remotely sensed
data to be processed in parallel and at great speed. Such configurations make the
distinction between mainframes and workstations fuzzy (Berry, 1993). RISC
workstations application software and hardware maintenance costs are usually
higher than personal computer based image processing systems.
Mainframe Computers (2:32-bit CPU) are generally more efficient than workstations, especially parallel mainframe computers such as a CRA Y (Earnshaw and
Wiseman, 1992). Mainframes are ideal for intensive CPU-dependent tasks such as
spatiaVfrequency filtering, image rectification, mosaicking of numerous scenes,
J. Jensen
how many millions-of-instructions-per-second (MIPS) it can process, e.g. 450
MIPS.
Personal computers (16- to 32-bit CPUs) are routinely used to perform digital
image processing and GIS analysis. These complex-instruction-set-computers
(CISC) have CPUs with 16- to 32-bit registers (word size) that compute integer
arithmetic expressions at greater clock speeds and process significantly more
MIPS than their 8-bit predecessors. 16-bit CPUs can process two 8-bit bytes at a
time while 32-bit CPUs can process four bytes at a time. Table 3.1 documents the
historical development of the Intel family of CPUs used in IBM compatible personal computers. Scientists often populate laboratories with PC-based digital image processing systems because the hardware and software are relatively inexpensive per unit and hardware maintenance is low. Typical personal computers cost
<$3,000 with 24-bits per pixel of image processor memory (with a 16.7 million
color lookup table) and a high resolution color monitor.
Table 3.1. Historical development of the Intel family of CPUs used in numerous IBM compatible personal computers (Freedman, 1995; Spooner, 1999)
CPU (word size)
Clock Speed (Mhz)
MIPS
8088 (16)
5
0.33
8086 (16)
5 - 10
0.33 - 0.66
286 (16)
6-12
I.2 - 2.4
386DX (32)
16 -40
6 - 15
486DX (32)
25 - 100
20 - 80
Pentium I
60- 200
100 - 250
Pentium II
300- 400
300 - 400
Pentium III Celeron
>466
>450
Computer Workstations (2:32-bit CPUs) usually consist of a 32 to 64-bit reducedinstruction-set-computer (RISC) that can address substantially more random access memory than personal computers. The RISC chip is faster than the traditional
CISC and is designed and built more economically (Freedman, 1995). Workstations also usually have a bank of 8- or 24-bit image processing memory and a very
high resolution color monitor (Denning, 1993). Figure 3.1 summarizes the components found in a typical digital image processing workstation laboratory. RISe
workstations can function independently or be networked to a file-server as
shown. Some RISC workstations have multiple CPUs that allow remotely sensed
data to be processed in parallel and at great speed. Such configurations make the
distinction between mainframes and workstations fuzzy (Berry, 1993). RISC
workstations application software and hardware maintenance costs are usually
higher than personal computer based image processing systems.
Mainframe Computers (2:32-bit CPU) are generally more efficient than workstations, especially parallel mainframe computers such as a CRA Y (Earnshaw and
Wiseman, 1992). Mainframes are ideal for intensive CPU-dependent tasks such as
spatiaVfrequency filtering, image rectification, mosaicking of numerous scenes,