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NAME

i.photo.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.photo.init
i.photo.init help
i.photo.init group=name [--verbose] [--quiet]

Parameters:

group=name
Name of imagery group for ortho-rectification

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.photo.init (menu 6) is only required when rectifying a tilted or oblique aerial photo.

i.photo.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.

The INITIAL values for (omega,phi,kappa) are expressed in degrees, and represent an approximation for the cameras attitude at the time of exposure.

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.camera, i.photo.2image, i.photo.2target, i.photo.rectify

AUTHOR

Mike Baba, DBA Systems, Inc.

Last changed: $Date: 2010-12-22 02:05:10 -0800 (Wed, 22 Dec 2010) $


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