[GRASS-user] Geometric Correction

[Markus Neteler]

On Wed, Feb 3, 2010 at 5:05 PM, Luis Lisboa <luislisboa1975 at gmail.com> wrote:
> While I was reading chapter 8, from Neteler & Mitasova GRASS Book, I
> realized that there is no specific sub-chapter related with Geometric
> Correction. This process is to compensate for the distortions introduced by
> these factors so that the corrected image will have the highest practical
> geometric integrity (Lillesand & Kiefer).
> My question is: How can this be done in GRASS?

The Imagery TODO list is the following:

- merge of image libraries:
  A)
    - lib/imagery/: standard lib, in use (i.* except for i.points3, i.rectify3)
    - imagery/i.ortho.photo/libes/: standard lib, in use
(i.ortho.photo, photo.*)
  B)
    - lib/image3/: never finished improvement which integrated the
standard lib and
                   the ortho lib. Seems to provide also ortho rectification for
                   satellite data (i.points3, i.rectify3)
- image modules:
    - merge of i.points, i.vpoints, i.points3
    - merge of i.rectify and i.rectify3
    - addition of new resampling algorithms such as bilinear, cubic convolution
      (take from r.proj?)
    - add other warping methods (maybe thin splines from GDAL?)
    - implement/finish linewise ortho-rectification of satellite data
    - Add support for > 8bit colors (only 0-255 supported currently)


Relevant for you is this:
- "implement/finish linewise ortho-rectification of satellite data"
...unfortunately stuck since GRASS 4/5...

> I suppose it's done since
> LANDSAT-TM need geometric correction and, all GRASS book refers to LANDSAT
> images.

(A part of the book refers to LANDSAT.)

It would be great to see the existing algorithms integrated.

Best
Markus