I have two Lansat 8 scenes from the same path/row and I try to perform topographic correction with i.topo.corr. I have converted all images to reflectance (DOS1) using i.landsat.toar. After that I tried to correct topography using i.topo.corr.
It seems to work fine with the 1st scene, but I get strange results with the 2nd scene: Range of Scene 1 (Band 5) before i.topo.corr: min = 0.133723349810153 max = 0.906354180100938 Range of Scene 1 (Band 5) after i.topo.corr: min = 0.133760732072622 max = 0.907846862031268 Seems fine. Range of Scene 2 (Band 5) before i.topo.corr: min = 0 max = 0.832036359894079 Range of Scene 2 (Band 5) after i.topo.corr: min = -17160.1716925017 max = 1438.29470705194 Don't understand why the value-range in scene 2 completely changes after i.topo.corr. Here's the r.univar output of both scenes: Band 5 of Scene 1: total null and non-null cells: 59299001 total null cells: 17799460 Of the non-null cells: ---------------------- n: 41499541 minimum: 0.133761 maximum: 0.907847 range: 0.774086 mean: 0.347903 mean of absolute values: 0.347903 standard deviation: 0.04205 variance: 0.0017682 variation coefficient: 12.0867 % sum: 14437827.9766821 Band 5 of Scene 2: total null and non-null cells: 59299001 total null cells: 17807526 Of the non-null cells: ---------------------- n: 41491475 minimum: -17160.2 maximum: 1438.29 range: 18598.5 mean: 0.145337 mean of absolute values: 0.157922 standard deviation: 5.53211 variance: 30.6042 variation coefficient: 3806.4 % sum: 6030253.47038046 Any ideas? Stefan -- View this message in context: http://osgeo-org.1560.x6.nabble.com/i-topo-corr-bug-in-GRASS-7-0-3-tp5291227.html Sent from the Grass - Users mailing list archive at Nabble.com. _______________________________________________ grass-user mailing list [email protected] http://lists.osgeo.org/mailman/listinfo/grass-user
