Digital Image Processing
Second Edition
Problem SolutionswStudent Set
Rafael C. Gonzalez
Richard E. Woods
Prentice Hall
Upper Saddle River, NJ 07458
www.prenhall.com/gonzalezwoods
or
www.imageprocessingbook.com
ii
Revision history
10 9 8 7 6 5 4 3 2 1
Copyright c°19922002 by Rafael C. Gonzalez and Richard E. Woods
1 Preface
This abbreviated manual contains detailed solutions to all problems marked with a star
in Digital Image Processing, 2nd Edition. These solutions can also be downloaded from
the book web site (www.imageprocessingbook.com).
2 Solutions (Students)
Problem 2.1
The diameter, x, of the retinal image corresponding to the dot is obtained from similar
triangles, as shown in Fig. P2.1. That is,
(d=2)
0:2
(x=2)
0:014
=
which gives x = 0:07d. From the discussion in Section 2.1.1, and taking some liberties
of interpretation, we can think of the fovea as a square sensor array having on the order of
337,000 elements, which translates into an array of size 580 £ 580 elements. Assuming
equal spacing between elements, this gives 580 elements and 579 spaces on a line 1.5
mm long. The size of each element and each space is then s = [(1:5mm)=1; 159] =
1:3£ 10¡6 m. If the size (on the fovea) of the imaged dot is less than the size of a single
resolution element, we assume that the dot will be invisible to the eye. In other words,
the eye will not detect a dot if its diameter, d, is such that 0:07(d) < 1:3 £ 10¡6 m, or
d < 18:6 £ 10¡6 m.
Figure P2.1
4
Chapter 2 Solutions (Students)
Problem 2.3
¸ = c=v = 2:998 £ 108(m/s)=60(1/s) = 4:99 £ 106m = 5000 Km.
Problem 2.6
Problem 2.9
Problem 2.11
One possible solution is to equip a monochrome camera with a mechanical device that
sequentially places a red, a green, and a blue pass filter in front of the lens. The strongest
camera response determines the color.
If all three responses are approximately equal,
the object is white. A faster system would utilize three different cameras, each equipped
with an individual filter. The analysis would be then based on polling the response of
each camera. This system would be a little more expensive, but it would be faster and
more reliable. Note that both solutions assume that the field of view of the camera(s) is
such that it is completely filled by a uniform color [i.e., the camera(s) is(are) focused on
a part of the vehicle where only its color is seen. Otherwise further analysis would be
required to isolate the region of uniform color, which is all that is of interest in solving
this problem].
(a) The total amount of data (including the start and stop bit) in an 8bit, 1024 £ 1024
image, is (1024)2 £ [8 + 2] bits. The total time required to transmit this image over a
At 56K baud link is (1024)2 £ [8 + 2]=56000 = 187:25 sec or about 3.1 min. (b) At
750K this time goes down to about 14 sec.
Let p and q be as shown in Fig. P2.11. Then, (a) S1 and S2 are not 4connected because
q is not in the set N4(p)u (b) S1 and S2 are 8connected because q is in the set N8(p)u
(c) S1 and S2 are mconnected because (i) q is in ND(p), and (ii) the set N4(p) \ N4(q)
is empty.