Nov 1993/Oct 1999/Dec. 1999

# 12/99: moved "image3/" to src/libes/

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# 10/99: the supplemental library "libe/" renamed to "image3/"
         and updated related Gmakefiles.

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This is the ALPHA source for three programs:
i.points3      - modified i.points program
i.rectify3     - modified i.rectify program
i.tape.tm3     - modified i.tape.tm program.

The nroff manual pages can be found in man/man1 and the processed man pages
under man/cat1. 

The TODO file contains a general list of thing to be finished or modified.

All three programs require the library routines $(IMAGERYLIB_SUP) which
are built from the source under image3/.

To compile, just run gmake5.x from the top most directory (i.e. where you
found this README file).  The source has been compiled successfully on 
SUN Sparc2 (SUN O/S 4.1.2) and SGI IRIS4/D (IRIX 4.something) and Linux.

These programs have not yet been tested on other machines or O/Ss, and 
have only been tested with very limited data.  

These programs are NOT guarenteed
to be bug-free, but should at present provide some users with improved 
performance over the existing programs.


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I.TAPE.TM3
  i.tape.tm3 is intended to replace both i.tape.tm and i.tape.tm.fast
i.tape.tm3 can distinquish between FULL SCEEN, QUAD SCEEN, and FAST-FORMAT
LANDSAT Thematic Mapper data sets.  i.tape.tm3 can be used with tape devices
(1/4 inch, 8-mm, and 9-track) as well as data stored on a filesystem in 
normal (or linked)  UNIX files.

  i.tape.tm3 provides similary capabilities to the original programs.  You
can examine the data set, extract selected TM bands, and extract the full
image or a windowed sub-set of the image.

  i.tape.tm3 has also be enhanced to extract CONTROL-POINT data from the
data set to be used with the i.points3 and i.rectify3 programs.  At present
the extracted control point data does not work for FAST-FORMAT Landsat data
sets.  

  This program is probally not as portable as it should be.  It need to 
be tested with different LANDSAT formats on a variety of media.



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I.POINTS3
  i.points3 is intended to be a more generic program used to mark control
points used in the image rectification process.  It looks and works much
like the original i.points program as well as i.vpoints.

  i.points3 can be used for POLYNOMAIAL, ORTHO-PHOTO, or LANDSAT-TM 
transfromations.   Polynomial transformation can be 1rst order like 
the original i.points program, or 2nd or 3rd order (like i.vpoints).

  The ORTHO-PHOTO transformation can be used along with an elevation model
to rectify and remove relief displacements in aerial photography.  This 
transformation preforms the same manipulations as the earlier program 
i.ortho.photo. 

  The LANDSAT-TM transformation is to be used with Thematic Mapper data
extracted by i.tape.tm3.  This transformation can be used with an elevation
model to remove relief displacement much like the ORTHO-PHOTO transformation.

  You can switch among the transformations using the same set of control
points.  However additional (auxillary) data may be required for the ORTHO-
PHOTO and LANDSAT-TM transformations.

  i.points3 alows you to display both raster and vector files in the 
target location from which control points can be selected.  You can 
also preform an "overlay" and "grid" routine to visually examine how
well the transformation will proceed without haveing to run the i.rectify
program.

  Currently the POLYNOMIAL transformation works very well.  The ORTHO-PHOTO
and LANDSAT-TM transformation work (for me) but have not been tested with
a lot of data or by other people. 


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I.RECTIFY3
  i.rectify3 is also intended as a more generic program than the original 
i.rectify program.  It works with the control point data and auxillary
information collected by i.points3.

  i.rectify3 can use the POLYNOMIAL, ORTHO-PHOTO, or LANDSAT-TM transfromations
discussed in i.points3.

  There should be not difference using the POLYNOMIAL transfromation in 
i.rectify3 from the earlier i.rectify or i.rectify2 programs.

  The ORTHO-PHOTO transformation provides a more detailed transfromation
than the earlier i.ortho.photo.  The LANDSAT-TM transformation is new to GRASS. 

  Currently the POLYNOMIAL transformation works very well.  The ORTHO-PHOTO
and LANDSAT-TM transformation work (for me) but have not been tested with
a lot of data or by other people. 



