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<body class='hmmessage'><div style="text-align: left;">Greetings,<br><br>I'm having an issue with a MrSid dataset. Performance seems to be dreadfully slow reprojecting data from this 14336 pix by 14336 pix 8bit, 3 band RGB, UTM rotated image with 8 overviews. Whether I warp the image into a 512 pix x 428 pix geotiff or a 15620 pix x 13102 pix geotiff, (EPSG:4326) both warp operations take over 5 minutes. (5:30 for the small image, 7:15 for the large which required 600 megabyte of disk output). <br><br>Might there be a better way of creating a VRT, grabbing one of the overview bands, and using this virtual "overview" dataset in the warp operation. Strangely enough, if I translate the source into a GeoTiff, and create 8 explicit overviews, the 512 pix x 428 pix warp operation takes about 30 seconds.<br><br>-- Dan Greve<br>-- Software Engineer<br>-- Northrop Grumman Integrated Systems<br></div><br /><hr />Climb to the top of the charts! Play the word scramble challenge with star power. <a href='http://club.live.com/star_shuffle.aspx?icid=starshuffle_wlmailtextlink_jan' target='_new'>Play now!</a></body>
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