Hi,<br><br>Function ProcessRecordHeaders in "formats/l1b/l1bdataset.cpp" subsamples the GCPs of the l1b image, but the points are unordered an not equidistant.<br><br>I attached to TCK 2403 a patch that modifies this behaviour. I tested the image attached to the ticket and seems to work ok(no error produced).<br>
<br>I also test the patched driver with an image of Argentina and worked ok.<br><br>I'd like to know if I misunderstood the intention of the code and the points in each line shouldn't be equidistant.<br><br>Thanks<br>
Ramiro<br><br><br><div class="gmail_quote">2011/6/15 Andrew Brooks <span dir="ltr"><<a href="mailto:arb@sat.dundee.ac.uk">arb@sat.dundee.ac.uk</a>></span><br><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex;">
<div class="gmail_quote">Hi</div><div class="gmail_quote"><br></div><div class="gmail_quote">From memory the l1b driver doesn't use enough points to get proper geolocation because it sub-samples the 51 which are provided in the l1b file. The best solution (that recommended by NOAA) is to use lagrange interpolation across the 51 points. A lagrange algorithm has been provided in the ticket you referenced but nobody has added it to gdal. I think at the moment you could consider the l1b driver broken.</div>
<div class="gmail_quote"><br></div><font color="#888888"><div class="gmail_quote">Andrew</div><div class="gmail_quote"><br></div>
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