Er
P = oêD-!= | (49')
_ Where
: n n
nr -2(n-2ng) A (n-2)7 Som i
= I=
ny=3(ngtng) , nc=3ns
Vfz(iVT 2VF ... a VI),
Vi= (Vf, Vi, Tee VE
1Cr
P
Cr (Ch Cr, t Ct. (50)
Gi- (GT :Gl ....GT ),
Gr= (Gy, Gp, +++ Gr,
Vi. A'S NE ee VE)
BB
1C5
2 Cs
Gi- (GI &G}, + GF )
I= 0" QF — QF)
U'- (Uf Uf I US
U!= ( Xo Yo Zo )
v={XYZ2)
Ds GA 205 IT)
{= (LA Le: Lion
Ly (Le 15 see l5]
In eq. (49) and (50), right subs are about photos or
ground points, left subs are equivolent to that of eqs (43)
-(48).
Eq. (49) is developed from co-angularity condition and
crown finding method, and belongs to the Gauss-Markoff
model, so we can call it Crown Co-angularity Gauss-
Markoff Model(CCGMM) or simplely Crown Model (CM).
The adjustment based on CCGMM is called Crown
Adjustment.
Refer to eqs. (49)-(50) we know that the parameter
vectors Q and Ug are both photo-invarriants, so we can
place them together in practical adjustment. From eq. (49)
we can easily find the properties of the model:
1 The normal equation can be composed one by one
image point (vertex) and photo (base), and reduced one
by one ground point (or photo) such as bundle
adjustment.
2) The sum of observation equations and the sum of the
parameters in crown method are both equal to that of
bundle method.
3) The angular orientations are not any more parameters
in this metod. This will make the computation convenient,
and broaden the application range of photogrammetry, for
example, in terrestral or close-range photogrammetry, we
For eqs. (40), we let
Ve=Q (42)
The residual vector Vc has been transformed to parameter
to parameter Q, we call it the first transformation.
The second equation of eqs. (40) left-handly multiplied by
p! , and substitute eq. (42) into it, we obtain
Vg-CsQ4GgU-Ls (43)
where
C p=-F glF c
--Fg!Bg (44)
L =F 8 Ws
The second equatiopn is transformed to an observation
one, we call this the second teansformution.
Substitute eqs. (42) and (43) into the first equation of eq.
(40), and merge the identical terms, we obtain
where
C' ra=A paC Bt ca
G' r1=ApsGstBra (46)
W' Ta7W r4-A pal B
At this time, we have eliminated the residual vector Vg
from the first equation of eqs. (40).
Eq. (45) left-handly multiplied by matrix Ars?, we obtain
Vra=Cr2Q+GraU-Lra (47)
where
C 137-A rà 7C ra
Gra=-Ara"Ges (48)
L r1=A ra Wra
Now that, the first equation of eq. (39) has been
transformed into an observation equation, this is called the
third and last transformation. Up to now, the general
form of co-angularity condition eq. (39) has been
thoroughly transformed into the expected observation
form. The approach consists of three transformations and
an elimination, so we call it Transformation with
Elimination Technique.
From eq. (42), (43) and (47), we know that the
observation form of co-angularity condition consists of
three types of equations. eq. (42) plays a part of control,
so is called the Control Equation; eq. (46) presents the
relation between the base points of the crown, then is
called the Base Equation; eq. (47) is for the vertex of the
crown, therefore is called verTex Equation.
The above equations are about just one vertex with the
base related to it. They can be conveniently expanded to
fit a block. Assume that a block consists of ng photos, ng
ground points and n image points, then the corresponding
Gauss-Markoff can be written as
Vr Cr Gr] | Q Lr
npxl ncxi
El Cs Gs - | Ls (49)
Vc Ec 0 U 0
ncxí
ngx1
<
w