Dear Sajid,
checking the source of the plugin I realized that different scales are
used in easting and northing direction. So the formulas look like:
E' = Eoffset + Escale * E
N' = Noffset - Nscale * N
The minus in N formula is because of the different axis direction in the
screen coordinates and map coordinates.
The four unknowns are calculated from a least squares estimation.
Regards,
Zoltan
On Wed, 13 Aug 2014, sajid pareeth wrote:
Hi Zortan
Thank you for the reply.
Would be great to know, how this Offsets and scale is calculated from a set
of GCP's.
Any idea?
Regards
Sajid
On Wed, Aug 13, 2014 at 3:30 PM, Siki Zoltan <s...@agt.bme.hu> wrote:
Dear Sajid,
linear transformation (from my practice) use three unknowns
offset (Easting, Northing) and scale. No rotational angle.
The linear is not a good name for it.
E' = Eoffset + scale * E
N' = Noffset + scale * N
Zoltan
On Wed, 13 Aug 2014, sajid pareeth wrote:
Hi,
Can anyone give me hints on statistical background behind linear
transformation in Georeferencer plugin?
I want to know the formulae used to calculate the residuals while using
linear translation.
Any related paper/material on which it is developed??
Thanks and Regards
Sajid
--
Sajid Pareeth
PhD Student
http://gis.cri.fmach.it/pareeth/
Fondazione Edmund Mach
Research and Innovation Centre
GIS and Remote Sensing Unit/Limnology and River ecology
Via Mach 1, 38010 San Michele all'Adige (TN) - Italy
Phone +39 461 615 669
spare...@gmail.com
sajid.pare...@fmach.it
skype: spareeth
--
Sajid Pareeth
http://gis.cri.fmach.it/pareeth/
Fondazione Edmund Mach
Research and Innovation Centre
GIS and Remote Sensing Unit/Limnology and River ecology
Via Mach 1, 38010 San Michele all'Adige (TN) - Italy
Phone +39 461 615 669
spare...@gmail.com
sajid.pare...@fmach.it
skype: spareeth
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