没有合适的资源?快使用搜索试试~ 我知道了~
Introduction to Mathematical Morphology
3星 · 超过75%的资源 需积分: 9 21 下载量 26 浏览量
2011-05-31
16:53:00
上传
评论
收藏 3.7MB PDF 举报
温馨提示
试读
23页
Introduction to Mathematical Morphology JEAN SERRA E. N. S. M. de Paris, Paris, France Received October 6,1983; revised March 20,1986 1. BACKGROUND
资源推荐
资源详情
资源评论
COMPUTER VISION, GRAPHICS, AND IMAGE PROCESSING 35, 283-305 (1986)
Introduction to Mathematical Morphology
JEAN SERRA
E. N. S. M. de Paris, Paris, France
Received October 6,1983; revised March 20,1986
1. BACKGROUND
As we saw in the foreword, there are several ways of approaching the description
of phenomena which spread in space, and which exhibit a certain spatial structure.
One such approach is to consider them as objects, i.e., as subsets of their space of
definition. The method which derives from this point of view is. called mathematical
morphology [l, 21. In order to define mathematical morphology, we first require some
background definitions.
Consider an arbitrary space (or set) E. The “objects” of this :space are the subsets
X
c
E; therefore, the family that we have to handle theoretically is the set 0 (E) of
all the subsets X of E. The set p(E) is incomparably less arbitrary than E itself;
indeed it is constructured to be a Boolean algebra [3], that is:
(i) p(E) is a complete lattice, i.e., is provided with a partial-ordering relation,
called inclusion, and denoted by “
c
.” Moreover every (finite or not) family of
members Xi E p(E) has a least upper bound (their union C/Xi) and a greatest
lower bound (their intersection f7 X,) which both belong to p(E);
(ii) The lattice p(E) is distributiue, i.e.,
xu(Ynz)=(XuY)n(xuZ) VX,Y,ZE b(E)
and is complemented, i.e., there exist a greatest set (E itself) and a smallest set 0
(the empty set) such that every X E p(E) possesses a complement Xc defined by the
relationships:
XUXC=E
and
xn xc= 0.
Given two sets X and Y E p(E), the notion of their set diference X/Y derives from
the intersection and the complement, as follows:
X/Y=Xn YC;
X/Y is the part of X which does not belong to Y (see Fig. lc). In brief, given two
sets B and X belonging to p(E), we may have (Fig. 1):
(a) B is included in X (notation: B c X)
(p) B hits X (notation: B fi X) meaning B
n X # 0
(y) B misses X (notation B c Xc) meaning B
n X = $I
and these relationships will apply when B is replaced by every family {B;).
Finally, the structure of a Boolean algebra provides the general framework on
which we shall perform morphological treatments. Mathematical morphology is the
application of lattice theory to spatial structures.
283
0734-189X/86 $3.00
Copyright $’ 1986 by Academic Press, lnc
All rights of reproduction in any form resrrwd
284
JEAN SERRA
FIG.
1. (a) B, hits X (B, R X); E, misses X (B2
C
Xc); B, is included in X (B,
C
X);
(b) complement X’ of set X; (c) difference X/Y of the two sets X and Y.
These definitions may seem rather abstract and far away from the practical
applications. As a matter of fact, we shall pursue the discussion by concentrating
mainly upon the Euclidean space R” with dimension n = 1,2, or 3, or its digital
version Z” in terms of grids of points. Pedagogically speaking, the Euclidean case is
the first to be considered, since it corresponds to the physical world in which we
live; on the other hand, many images are reasonably binary, at least in a first
approximation (such as microstructures (Fig. 10) biological cells, (Fig. 11) seg-
mented zones in remote sensing, etc.). However, to restrict the approach to the
Euclidean sets would mean ignoring other important domains to which the method
applies. Let us briefly quote, for example:
-functions of W” considered as sets of R
x
Wn-‘, via their umbrae (see [25]);
-planar graphs, such as the partition of a map into counties [4];
-products of spaces, when several images are defined at each pixel. The
conditional operations introduced in Sections 5 and 6 below illustrate this mor-
phology. They result in context dependent transformations;
-vector spaces, such as propagations, when a range of directions is function of
each pixel [5];
-topological spaces which are necessary for introducing probabilities, and for
treating the questions of robustness [l];
-etc.
All in all, these various extensions indicate that we have to keep in mind two
different levels of generality: the Euclidean (or digital) binary case, which is useful
and gives a good intuition of what is going on, and the Boolean algebra associated
with the general framework of the method.
2. MORPHOLOGICAL TRANSFORMATIONS
2.a. Hit-or-Miss Transformation, Dilation, Erosion
The final goal of computer vision is often to segment images into objects and
textures in accordance with the judgment of the human eye. But this is not always
the case. It may happen that slight nuances escape human perception although they
INTRODUCTION
2X5
FIG. 2. (a) Cat brain cortex after hypoxia. The human eye does not detect the slightest difference with
the normal state. Nevertheless, by investigating one thousand neurons by morphological openings,
significant differences are exhibited [6]. (b) Sandstone rock from the oil reservoir of Hassi-Messaoud
(Sahara): how does one predict the permeability of this material from its texture?
are significant (see Fig. 2a). Moreover, the purpose of an image treatment may not
be to match vision, but to estimate some physio-chemical properties. In the case of
Fig. 2b, the Navier-Stokes equation, which governs the physical process, corre-
sponds to nothing intuitive.
Therefore, we do not look for a computerized substitute for human vision, but for
a coherent framework for describing spatial organization.
To this end, we define the
structure of an object by the set of the relationships existing between the various
parts of the object. We will study the structure experimentally by trying each of the
possible relationships in turn, and examining whether or not it is satisfied. Of
course, such knowledge will greatly depend on the choice made for the system of
relationships considered possible, and this a priori choice determines the relative
worth of the resulting concept of structure.
We saw that the media under study may have no recognizable pattern. This lack
of meaning (for us) leads to the position of probing them systematically, by starting
from the simplest relations that one can imagine. From this comes the idea of a
structuring element.
With each point x of the space
E
in which we work, we
associate a set B(x) called a structuring element. (Note that B(x) may vary from
one place to another). We can modify every set x E $I(
E)
by some B(x) in several
ways. The most important ones are as follows:
dilation of X: (x: B(x) fl X}
(1)
erosionof X: {x: B(x)
C
X}.
(2)
The dilation of X by B(x) is the set of all the points x such that B(x) hits X. The
erosion of X by B(x) is the set of all the points x such that B(x) is included in X.
Starting from two structuring elements B’(x) and B2(x) we also define the
286
JEAN SERRA
hit-or-miss transformation (in brief HMT) as being the difference of X eroded by
B’(x) and X dilated by B2(x).
HMT of X: (erosion of X by B’)/(dilation of X by B2).
Dilation and erosion turn out to be particular cases of HMTs.
The class of transformations generated by the (possibly infinite) unions, products,
and complementations of HMTs constitutes, by definition, the
morphological truns-
formations
over p(E). Of course, these operations are not the only pieces of
information; in particular, they can be combined with measures on p(E) (e.g., the
area or the volume of sets in the Euclidean space) or with other types of operations
(convolution, for example).
2. b. Basic Properties
First of all, a general comment: all of the morphological transformations are
non-reversible, (except, in each particular case, for some subclasses of sets such as
the invariant ones). In fact, the idea of restoring the images is quite irrelevant here;
on the contrary, our philosophy will consist of stating that the images under study
exhibit too much information, and that the goal of any morphological treatment is
to
manage the loss of information
through the successive transformations.
In order to do this, we must play with a few underlying general properties which
are the key to any morphological analysis. We now present the four most important
ones. In what follows, $ is the generic symbol of a morphological transformation.
(i)
Increasing:
4 is increasing when it preserves inclusion, i.e., when
xc y=, 44x) = J/(y)
‘dx, YE b(E).
(4)
For example, the transformation “replace X by its boundary JX” is
not
increasing.
(ii)
Anti-extensiuity:
r/ is anti-extensive when it shrinks X, i.e., when
J/(x) = x
Vx E b(E).
(5)
(iii)
Idempotence:
# is idempotent when the result q(X) remains unchanged if
we reapply the transformation, i.e., when
vwxN = W)
vx E b(E).
(6)
(iv)
Homotopy:
Here the set
E
is considered as a topological space. However,
for the sake of simplicity, we limit ourselves to the bounded sets of the plane. With
each bounded set
K,
associate its
homotopy tree
whose trunk corresponds to the
background
K,
(i.e., the infinite connected component of
Kc),
the first branches
corresponding to the connected components
K1
of
K
adjacent to
K,
and the second
branches to the pores
K,
of
K
adjacent to
K,,
etc. (see Fig. 3).
INTRODUCTION
287
FIG.
3. Two homotopic figures and their tree.
A transformation is homotopic when it preserves the homotopic tree of K. Note
that homotopy is more severe than connectivity: a disk and a ring are both
connected sets, but they are not homotopic.
These four properties are the corner stones for a classification of the morphologi-
cal criteria. The reader must always keep them in mind if he wants to master the
method. However, they are far from being the only ones; one may also wish to treat
figure and background symmetrically, to perform isotropic analyses, to preserve
connectivity, to be monotonic at each pixel, etc.
Table 1 lists the status of the four properties for the basic Euclidean morphologi-
cal transformations and a few other geometrical transformations (displacements,
convex hulls, etc.) introduced in this paper and accompanying papers in this issue.
TABLE 1
Euclidean Morphological Criteria and Their Basic Properties
--__-.
Properties
Extensive (or anti- Preserve
Criteria
Increasing extensive)
Idempotent homotopy
_I- - -~ .-~
Complementation, Hit-or-Miss, No
NO
No No
boundary
Erosion and dilation when the Yes No No No
origin is not contained in the
structuring element, median
filtering
Thinning and thickening
No
Yes
No
No
Erosion and dilation when the Yes Yes No No
origin is contained in the struc-
turing element
Boundary of the boundary No No Yes No
Projection, morphological filtering Yes No Yes No
Sequential thinning, &ix, skeleton, No Yes Yes No
cond. bisector watershed, ulti-
mate erosion
Opening, closing, convex hull, size Yes Yes Yes No
distribution, thresholding,
umbra
Displacement, similarity, al&ity, Yes No No Yes
symmetry
Homotopic and sequential thin- No Yes
Yes Yes
ning and thickening
剩余22页未读,继续阅读
资源评论
- tianya103192016-08-25写文章参考,资料不错
jhjun65963296
- 粉丝: 0
- 资源: 1
上传资源 快速赚钱
- 我的内容管理 展开
- 我的资源 快来上传第一个资源
- 我的收益 登录查看自己的收益
- 我的积分 登录查看自己的积分
- 我的C币 登录后查看C币余额
- 我的收藏
- 我的下载
- 下载帮助
最新资源
- 教学内容及补充-cha7.rar
- 设计1.ms14
- vscode-1.64.1.tar源码文件
- vscode-1.64.0.tar源码文件
- vscode-1.52.0.tar源码文件
- Music-Player +PlayerActivity+ rockplayer+ SeeJoPlayer 播放器JAVA源码
- vscode-1.46.0.tar源码文件
- 最近很火植物大战僵尸杂交版2.08苹果+安卓+PC+防闪退工具V2+修改工具+高清工具+通关存档整合包更新
- 超级好用的截图工具PixPin,可录制Gif图
- Screenshot_2024-05-21-17-06-42-64_2332cb9b27b851b548ba47a91682926c.jpg
资源上传下载、课程学习等过程中有任何疑问或建议,欢迎提出宝贵意见哦~我们会及时处理!
点击此处反馈
安全验证
文档复制为VIP权益,开通VIP直接复制
信息提交成功