[QGIS Commit] r8252 - docs/trunk/english_us/user_guide
svn_qgis at osgeo.org
svn_qgis at osgeo.org
Wed Mar 19 14:34:19 EDT 2008
Author: dassau
Date: 2008-03-19 14:34:19 -0400 (Wed, 19 Mar 2008)
New Revision: 8252
Modified:
docs/trunk/english_us/user_guide/plugins_georeferencer.tex
Log:
link updates and small fixes from Carlos D?\195?\161vila for georeferencer.tex in userguide trunk
Modified: docs/trunk/english_us/user_guide/plugins_georeferencer.tex
===================================================================
--- docs/trunk/english_us/user_guide/plugins_georeferencer.tex 2008-03-19 18:06:22 UTC (rev 8251)
+++ docs/trunk/english_us/user_guide/plugins_georeferencer.tex 2008-03-19 18:34:19 UTC (rev 8252)
@@ -8,12 +8,12 @@
As an example we will generate a world file for a topo sheet of South Dakota
from SDGS. It can later be visualized together with in the data of the GRASS
spearfish60 location. You can download the topo sheet here: \\
-\url{http://grass.itc.it/sampledata/spearfish\_toposheet.tar.gz}
+\url{http://grass.osgeo.org/sampledata/spearfish\_toposheet.tar.gz}
As a first step we download the file and untar it.
\begin{verbatim}
-wget http://grass.itc.it/sampledata/spearfish_toposheet.tar.gz
+wget http://grass.osgeo.org/sampledata/spearfish_toposheet.tar.gz
tar xvzf spearfish_toposheet.tar.gz
cd spearfish_toposheet
\end{verbatim}
@@ -40,15 +40,15 @@
With the button \textsl{Add Point} you can start to add points on the
raster image and enter their coordinates, and the plugin will compute the
-world file parameters (see figure \ref{fig:choose_points}). The more coordinates you provide the better the
-result will be. For the procedure you have two option.
+world file parameters (see Figure \ref{fig:choose_points}). The more coordinates you provide the better the
+result will be. For the procedure you have two options:
\begin{enumerate}
\item You click on a point in the raster map and enter the X and Y
coordinates manually
\item You click on a point in the raster map and choose the button
\textsl{from map canvas} to add the X and Y coordinates with the help
-of a georeference map already loaded in QGIS.
+of a georeferenced map already loaded in QGIS.
\end{enumerate}
\begin{figure}[ht]
@@ -61,31 +61,31 @@
For this example we use the second option and enter the coordinates for the
selected points with the help of the \textsl{roads} map provided with the
\textsl{spearfish60} location from: \\
-\url{http://grass.itc.it/sampledata/spearfish\_grass60data-0.3.tar.gz}
+\url{http://grass.osgeo.org/sampledata/spearfish\_grass60data-0.3.tar.gz}
If you don't know how to integrate the spearfish60 location with the GRASS plugin,
-information are provided in Section \ref{sec:grass}.
+information are provided in Section \ref{sec:grass}.
As you can see in Figure \ref{fig:choose_points}, the georeferencer provides buttons
-to zoom, pan, add and delete points in the image.
+to zoom, pan, add and delete points in the image.
After you added enough points to the image you need to select the transformation
type for the georeferencing process and save the resulting world file together with
-the Tiff. In our example we choose linear transformation although a helmert
-transformation might be sufficient as well.
+the Tiff. In our example we choose linear transformation although a Helmert
+transformation might be sufficient as well.
\begin{Tip}\caption{\textsc{Choosing the transformation type}}
-\qgistip{The linear (affine) transformation is a 1st order transformation and used
+\qgistip{The linear (affine) transformation is a 1st order transformation and is used
for scaling, translation and rotation of geometrically correct images. With the
-helmert transformation you simply add coordinate information to the image like
+Helmert transformation you simply add coordinate information to the image like
geocooding. If your image is contorted you will need to use software that provides
2nd or 3rd order polynomial transformation, e.g. GRASS GIS.
}
\end{Tip}
The points we added to the map will be stored in a \textsl{spearfish\_topo24.tif.points} file together
-with the raster image. This allows us to reopen the georeferencer plugin and to add new or delete
-existing points to optimize the result. The \textsl{spearfish\_topo24.tif.points} file of this
+with the raster image. This allows us to reopen the georeferencer plugin and to add new points or delete
+existing ones to optimize the result. The \textsl{spearfish\_topo24.tif.points} file of this
example shows the points:
\begin{verbatim}
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