Frederick,<div><br></div><div>GDAL considers the position (0.0,0.0) as the top left part of the top left pixel [1]. So, the center of the top left pixel would be (0.5,0.5). This could be the cause of the linear shift.</div>
<div><br></div><div>[1]: <a href="http://www.gdal.org/gdal_datamodel.html">http://www.gdal.org/gdal_datamodel.html</a> (Affine GeoTransform)<br><br><div class="gmail_quote">On Thu, Jun 30, 2011 at 7:39 PM, frederick keusch <span dir="ltr"><<a href="mailto:frederick.keusch@digimapas.cl">frederick.keusch@digimapas.cl</a>></span> wrote:<br>
<blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex;">Hi Chaitanya,<br>
<br>
after intenting a lot of things to solve the problem including shift grids<br>
for example, we came back to the method with gdal_translate and gdalwarp you<br>
described. And it does work more or less. I did give GCP`s to the corners of<br>
the images and also in the images. The problem is, that after doing the<br>
warp, it seems like the image is shifted linear, all to the GCP in the upper<br>
left corner, so the East-coordinate e.g. upper left and lower left and upper<br>
right and lower right are identlical, what should not be. Using gdalinfo<br>
after using gdal_translate shows, that the manually given GCP´s were<br>
accepted, but after warping erverthing seems to move just linear, no matter<br>
if the option -geoloc was used or not...<br>
So I hope, maybe you could or some could have an idea , what could be the<br>
problem...<br>
<br>
Thanks in advance,<br>
<br>
frederick<br>
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</div></div></blockquote></div><br><br clear="all"><br>-- <br>Best regards,<br>Chaitanya kumar CH.<br>/tʃaɪθənjə/ /kʊmɑr/ <br>+91-9494447584<br>17.2416N 80.1426E<br>
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