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- bullseye 7.8.5-1+deb11u1
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i.ortho.init(1grass) | GRASS GIS User's Manual | i.ortho.init(1grass) |
NAME¶
i.ortho.init - Interactively creates or modifies entries in a camera initial exposure station file for imagery group referenced by a sub-block.
KEYWORDS¶
imagery, orthorectify
SYNOPSIS¶
i.ortho.init
i.ortho.init --help
i.ortho.init [-rp] group=name
[xc=float] [yc=float] [zc=float]
[xc_sd=float] [yc_sd=float]
[zc_sd=float] [omega=float]
[phi=float] [kappa=float]
[omega_sd=float] [phi_sd=float]
[kappa_sd=float] [--help] [--verbose]
[--quiet] [--ui]
Flags:¶
Parameters:¶
- group=name [required]
-
Name of imagery group for ortho-rectification - xc=float
-
Initial Camera Exposure X-coordinate - yc=float
-
Initial Camera Exposure Y-coordinate - zc=float
-
Initial Camera Exposure Z-coordinate - xc_sd=float
-
Apriori X-coordinate standard deviation - yc_sd=float
-
Apriori Y-coordinate standard deviation - zc_sd=float
-
Apriori Z-coordinate standard deviation - omega=float
-
Initial Camera Omega (roll) degrees - phi=float
-
Initial Camera Phi (pitch) degrees - kappa=float
-
Initial Camera Kappa (yaw) degrees - omega_sd=float
-
Apriori Omega (roll) standard deviation - phi_sd=float
-
Apriori Phi (pitch) standard deviation - kappa_sd=float
-
Apriori Kappa (yaw) standard deviation
DESCRIPTION¶
Aerial photographs may be either vertical or oblique. Vertical
photographs can be truly vertical (nadir), or slightly tilted (less than 3
degree from the vertical). Usually aerial photos are tilted to some degree.
We refer to the term vertical photograph up to a tilt of 3 degree.
Oblique aerial photographs are purposely taken with an angle between 3 and 90
degree from the nadir direction.
The use of i.ortho.init (menu 6) is only required when rectifying a tilted or oblique aerial photo.
i.ortho.init creates or modifies entries in a camera initial exposure station file for imagery group referenced by a sub-block. These entries include: the (XC,YC,ZC) standard (e.g. UTM) approximate coordinates of the camera exposure station; initial roll, pitch, and yaw angles (in degrees) of the cameras attitude; and the a priori standard deviations for these parameters. During the imagery program, i.photo.rectify, the initial camera exposure station file is used for computation of the ortho-rectification parameters. If no initial camera exposure station file exist, the default values are computed from the control points file created in i.photo.2target.
The following menu is displayed:
Please provide the following information INITIAL XC: Meters __________ INITIAL YC: Meters __________ INITIAL ZC: Meters __________ INITIAL omega (roll) degrees: __________ INITIAL phi (pitch) degrees: __________ INITIAL kappa (yaw) degrees: __________ Standard Deviation XC: Meters __________ Standard Deviation YC: Meters __________ Standard Deviation ZC: Meters __________ Std. Dev. omega (roll) degrees: __________ Std. Dev. phi (pitch) degrees: __________ Std. Dev. kappa (yaw) degrees: __________
Use these values at run time? (1=yes, 0=no)
AFTER COMPLETING ALL ANSWERS, HIT <ESC> TO CONTINUE
(OR <Ctrl-C> TO CANCEL)
The INITIAL values for (XC,YC,ZC) are expressed in standard (e.g. UTM) coordinates, and represent an approximation for the location of the camera at the time of exposure.
- X: East aircraft position;
- Y: North aircraft position;
- Z: Flight altitude above sea level
The INITIAL values for (omega,phi,kappa) are expressed in degrees, and represent an approximation for the cameras attitude at the time of exposure.
- Omega (roll): Raising or lowering of the wings (turning around the aircraft’s axis);
- Phi (pitch): Raising or lowering of the aircraft’s front (turning around the wings’ axis);
- Kappa (yaw): Rotation needed to align the aerial photo to true north: needs to be denoted as +90 degree for clockwise turn and -90 degree for a counterclockwise turn.
The standard deviations for (XC,YC,ZC) are expressed in meters, and are used as a priori values for the standard deviations used in computation of the ortho rectification parameters.
The standard deviations for (omega,phi,kappa) are expressed in degrees, and are used as a priori values for the standard deviations used in computation of the ortho rectification parameters.
If Use these values at run time? (1=yes, 0=no) is set to 0, the values in this menu are not used.
SEE ALSO¶
i.ortho.photo, i.photo.2image, i.photo.2target, i.ortho.elev, i.ortho.camera, i.ortho.transform, i.photo.rectify
AUTHOR¶
Mike Baba, DBA Systems, Inc.
SOURCE CODE¶
Available at: i.ortho.init source code (history)
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