Level 2 Help for TPTEDT2

INP

Input mark format tiepoints file created by program TRACKER.
Contains 4 word groups leftline,leftsample,rightline,rightsample.
real format 512 byte records. Bad points are zeroed out.


OUT

Identical to INP except deleted tiepoints are zeroed out.


NPTS

Number of tiepoints in the near vicinity of each tiepoint to use in
a least squares fit to predict that tiepoint from it's neighbors.
Must be between 4 and 20.


DISTANCE

Weighting distance used in weighting points according to their
distance.  Weight=DISTANCE/(d+1)  where d is the distance to each 
tiepoint in pixels.


LENGTH

The maximum vector length permitted. Any vector longer than this is rejected.


ANGLE

Maximum permitted angle deviation between the tiepoint vector and
the vector predicted from the neighboring tiepoint vectors.
In degrees.
       If Ar is the vector angle and Ap is the predicted
       angle then the tiepoint is deleted if:
       abs(Ar-Ap)*Lr/(Lr+BIAS) > ANGLE
See the BIAS keyword.


RANGE

Maximum permitted length deviation between the tiepoint vector and
the vector predicted from the neighboring tiepoint vectors.
This is a ratio between 0 and 1.
       If Lr is the  vector length and Lp is the predicted
       length then the tiepoint is deleted if:
       abs(Lr-Lp)/(Lr+Lp+BIAS) > RANGE
See the BIAS keyword.


BIAS

BIAS protects short vectors from being deleted. It should be set to
about the length of the shortest vectors which one considers to begin
to be immune from testing. 
For purposes of geoms or morphing a vector of nearly zero length does no harm.
Such a short vector really points nowhere and it's angle is meaningless. You
generally want to keep it.


BOTH

Both range and angle checks must be violated for a point to be deleted.
The default is to delete the tiepoint if either check fails.