3
in the image xd, Ya 2s well as the partial derivations Lae
to fg are calculated by using tne transformation parame-
ters contained in (2.1).
An AP operates according to the described algorithm as follows:
The model is subdivided into spatial segments. For each seg-
nent the centre coordinates Po, the appertaining image co-
ordinates Pe ‚and. the appertaining values of the partial
differentials and of the remainder terms are stored. Each
tine when passing from one segment to a neighbouring segment
the entire parameter set is changed (Fig. 2.1).
35 ct «+
ti
3. APPLICATION OF TAYLOR'S FORMULA 70 CEHNTRAL-PERSPECTIVZ
IMAGES
3.1 Derivation of the partial differentials
The fundamental relationships of analytical photozrammetry
between image coordinates x', y! and model coordinates X4 UJ.
are for the left image
N
-}
x E X a4
y! = 1/N . A 4 yy (3.4%)
-C ge ZA >
From these follow the two well-known collinearity equations.
Expanding them according to (2.2) we obtain
x x! dx n | c 0 se
x 1 e -
ai. Fed dy | + with F, = = = wit]
y' yg dz Ry! e [O3 € uM
{ = es oth J: aa Da CU m ag (3.2)
3.2 Derivation and discussion of the remainder terns
According to the possibilities shown in Section 2. the calcu-
lation of the remainder Serms: is first accomplished by
inversion of (2.2).
Ro sx'-x»€d4, Rs y! Rye dy (3.5)
For the renainder terms in matrix notation one obtains
Red! d dx!
X 4
si. ME. (3.6)
Ry) Cord dy"
with ad = agy'dkx + azydy + azı-dz.
The comparison of (3.6) with the remainder terms according
to (2.3) leads to the relationship
Taylor (= 0)
B. ne
" ect Y Th a (3.7)
Taylor = (
Ry $, «4$ Ryr
-
Hy
in an aerial photo pair height differences of + 15% of the
505 +