Hi Chetan,<div><br></div><div>I have been working a lot with SLC-Off imagery lately. Some people in my department have used the gap filling programs floating around the net, but I'm not familiar with them personally. I've settled on using r.patch as well, although you have to be careful how you apply it. I found that even if I used radiometrically corrected landsat images (using i.landsat.toar) from the same season often the patched parts of the image did not fit smoothly with the rest of the image (i.e. you could see striations where the gaps had been). I'm using the imagery for land classification, so I've found it works better if I do the classification on each landsat image separately and then patch them. Using this method you can't tell where the former gaps are, at least in my experience working with imagery from the dry season in southeast asia. </div>
<div><br></div><div>Good luck!</div><div>Nick<br><br><div class="gmail_quote">On Fri, Dec 3, 2010 at 10:35 PM, Chethan S <span dir="ltr"><<a href="mailto:chethanuniversal@gmail.com">chethanuniversal@gmail.com</a>></span> wrote:<br>
<blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex;">Greetings!<br><br>I am using Landsat 7 ETM+ SLC-Off imageries for my academic project work. As users may be aware due to Scan line corrector going off in the satellite, large gaps are created in each band of image. It accounts for loss of 20 to 22 percent of data. Since recently, gap mask files are provided along with Landsat data, <font style="font-family:arial,helvetica,sans-serif" face="sans-serif" size="2">so you can tell where actual
<span>data</span> is versus the gaps, also all <span>data</span> gaps have a digital value <span>of</span> 0 (zero).</font>
<br><br>Options to use fill in those gaps created include using interpolation methods, usage of images from different dates or sensors like IRS or MODIS, usage of geostatistics etc. I am interested to know if anyone has employed such methods in GRASS previously. Proven techniques would help me progress faster.<br>
<br>Thanks and Regards,<br><br>Chethan S.<br clear="all"><br>-- <br><font color="#888888"><font style="color:rgb(102, 102, 0)" size="4"><span style="font-family:trebuchet ms,sans-serif">Chethan S.</span></font><span style="font-family:trebuchet ms,sans-serif;color:rgb(0, 0, 0)"></span><br>
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