One of our user of MapWindow GIS noticed a shift of its geotiff by one pixel width.<br><br>I took a look at it to see if the problem is with MapWindow or GDAL, because MapWindow uses GDAL internally.<br><br>The provided metadata of the geotiff is:<br>
<font style="font-family: courier new,monospace;" size="1">GROUP = L1_METADATA_FILE<br> GROUP = METADATA_FILE_INFO<br> ORIGIN = "Image courtesy of the U.S. Geological Survey"<br> REQUEST_ID = "0101004096683_00045"<br>
PRODUCT_CREATION_TIME = 2010-04-12T00:11:01Z<br> STATION_ID = "EDC"<br> LANDSAT7_XBAND = "2"<br> GROUND_STATION = "EDC"<br> LPS_PROCESSOR_NUMBER = 1<br> DATEHOUR_CONTACT_PERIOD = "0226604"<br>
SUBINTERVAL_NUMBER = "08"<br> END_GROUP = METADATA_FILE_INFO<br> GROUP = PRODUCT_METADATA<br> PRODUCT_TYPE = "L1T"<br> ELEVATION_SOURCE = "GLS2000"<br> PROCESSING_SOFTWARE = "LPGS_11.0.0"<br>
EPHEMERIS_TYPE = "DEFINITIVE"<br> SPACECRAFT_ID = "Landsat7"<br> SENSOR_ID = "ETM+"<br> SENSOR_MODE = "SAM"<br> ACQUISITION_DATE = 2002-09-23<br> SCENE_CENTER_SCAN_TIME = 00:09:22.3202747Z<br>
WRS_PATH = 95<br> STARTING_ROW = 85<br> ENDING_ROW = 85<br> BAND_COMBINATION = "123456678"<br> PRODUCT_UL_CORNER_LAT = -35.0709086<br> PRODUCT_UL_CORNER_LON = 140.3495920<br> PRODUCT_UR_CORNER_LAT = -35.0547004<br>
PRODUCT_UR_CORNER_LON = 143.0866731<br> PRODUCT_LL_CORNER_LAT = -37.0344333<br> PRODUCT_LL_CORNER_LON = 140.3332320<br> PRODUCT_LR_CORNER_LAT = -37.0170222<br> PRODUCT_LR_CORNER_LON = 143.1391164<br> PRODUCT_UL_CORNER_MAPX = 440700.000<br>
PRODUCT_UL_CORNER_MAPY = -3881100.000<br> PRODUCT_UR_CORNER_MAPX = 690300.000<br> PRODUCT_UR_CORNER_MAPY = -3881100.000<br> PRODUCT_LL_CORNER_MAPX = 440700.000<br> PRODUCT_LL_CORNER_MAPY = -4098900.000<br>
PRODUCT_LR_CORNER_MAPX = 690300.000<br> PRODUCT_LR_CORNER_MAPY = -4098900.000<br> PRODUCT_SAMPLES_PAN = 16641<br> PRODUCT_LINES_PAN = 14521<br> PRODUCT_SAMPLES_REF = 8321<br> PRODUCT_LINES_REF = 7261<br>
PRODUCT_SAMPLES_THM = 8321<br> PRODUCT_LINES_THM = 7261<br> BAND1_FILE_NAME = "L71095085_08520020923_B10.TIF"<br> BAND2_FILE_NAME = "L71095085_08520020923_B20.TIF"<br> BAND3_FILE_NAME = "L71095085_08520020923_B30.TIF"<br>
BAND4_FILE_NAME = "L71095085_08520020923_B40.TIF"<br> BAND5_FILE_NAME = "L71095085_08520020923_B50.TIF"<br> BAND61_FILE_NAME = "L71095085_08520020923_B61.TIF"<br> BAND62_FILE_NAME = "L72095085_08520020923_B62.TIF"<br>
BAND7_FILE_NAME = "L72095085_08520020923_B70.TIF"<br> BAND8_FILE_NAME = "L72095085_08520020923_B80.TIF"<br> GCP_FILE_NAME = "L71095085_08520020923_GCP.txt"<br> METADATA_L1_FILE_NAME = "L71095085_08520020923_MTL.txt"<br>
CPF_FILE_NAME = "L7CPF20020701_20020930_06"<br> END_GROUP = PRODUCT_METADATA<br> GROUP = MIN_MAX_RADIANCE<br> LMAX_BAND1 = 191.600<br> LMIN_BAND1 = -6.200<br> LMAX_BAND2 = 196.500<br> LMIN_BAND2 = -6.400<br>
LMAX_BAND3 = 152.900<br> LMIN_BAND3 = -5.000<br> LMAX_BAND4 = 241.100<br> LMIN_BAND4 = -5.100<br> LMAX_BAND5 = 31.060<br> LMIN_BAND5 = -1.000<br> LMAX_BAND61 = 17.040<br> LMIN_BAND61 = 0.000<br> LMAX_BAND62 = 12.650<br>
LMIN_BAND62 = 3.200<br> LMAX_BAND7 = 10.800<br> LMIN_BAND7 = -0.350<br> LMAX_BAND8 = 243.100<br> LMIN_BAND8 = -4.700<br> END_GROUP = MIN_MAX_RADIANCE<br> GROUP = MIN_MAX_PIXEL_VALUE<br> QCALMAX_BAND1 = 255.0<br>
QCALMIN_BAND1 = 1.0<br> QCALMAX_BAND2 = 255.0<br> QCALMIN_BAND2 = 1.0<br> QCALMAX_BAND3 = 255.0<br> QCALMIN_BAND3 = 1.0<br> QCALMAX_BAND4 = 255.0<br> QCALMIN_BAND4 = 1.0<br> QCALMAX_BAND5 = 255.0<br>
QCALMIN_BAND5 = 1.0<br> QCALMAX_BAND61 = 255.0<br> QCALMIN_BAND61 = 1.0<br> QCALMAX_BAND62 = 255.0<br> QCALMIN_BAND62 = 1.0<br> QCALMAX_BAND7 = 255.0<br> QCALMIN_BAND7 = 1.0<br> QCALMAX_BAND8 = 255.0<br>
QCALMIN_BAND8 = 1.0<br> END_GROUP = MIN_MAX_PIXEL_VALUE<br> GROUP = PRODUCT_PARAMETERS<br> CORRECTION_METHOD_GAIN_BAND1 = "CPF"<br> CORRECTION_METHOD_GAIN_BAND2 = "CPF"<br> CORRECTION_METHOD_GAIN_BAND3 = "CPF"<br>
CORRECTION_METHOD_GAIN_BAND4 = "CPF"<br> CORRECTION_METHOD_GAIN_BAND5 = "CPF"<br> CORRECTION_METHOD_GAIN_BAND61 = "CPF"<br> CORRECTION_METHOD_GAIN_BAND62 = "CPF"<br> CORRECTION_METHOD_GAIN_BAND7 = "CPF"<br>
CORRECTION_METHOD_GAIN_BAND8 = "CPF"<br> CORRECTION_METHOD_BIAS = "IC"<br> BAND1_GAIN = "H"<br> BAND2_GAIN = "H"<br> BAND3_GAIN = "H"<br> BAND4_GAIN = "L"<br>
BAND5_GAIN = "H"<br> BAND6_GAIN1 = "L"<br> BAND6_GAIN2 = "H"<br> BAND7_GAIN = "H"<br> BAND8_GAIN = "L"<br> BAND1_GAIN_CHANGE = "0"<br> BAND2_GAIN_CHANGE = "0"<br>
BAND3_GAIN_CHANGE = "0"<br> BAND4_GAIN_CHANGE = "0"<br> BAND5_GAIN_CHANGE = "0"<br> BAND6_GAIN_CHANGE1 = "0"<br> BAND6_GAIN_CHANGE2 = "0"<br> BAND7_GAIN_CHANGE = "0"<br>
BAND8_GAIN_CHANGE = "0"<br> BAND1_SL_GAIN_CHANGE = 0<br> BAND2_SL_GAIN_CHANGE = 0<br> BAND3_SL_GAIN_CHANGE = 0<br> BAND4_SL_GAIN_CHANGE = 0<br> BAND5_SL_GAIN_CHANGE = 0<br> BAND6_SL_GAIN_CHANGE1 = 0<br>
BAND6_SL_GAIN_CHANGE2 = 0<br> BAND7_SL_GAIN_CHANGE = 0<br> BAND8_SL_GAIN_CHANGE = 0<br> SUN_AZIMUTH = 49.0012493<br> SUN_ELEVATION = 41.9440742<br> OUTPUT_FORMAT = "GEOTIFF"<br> END_GROUP = PRODUCT_PARAMETERS<br>
GROUP = CORRECTIONS_APPLIED<br> STRIPING_BAND1 = "NONE"<br> STRIPING_BAND2 = "NONE"<br> STRIPING_BAND3 = "NONE"<br> STRIPING_BAND4 = "NONE"<br> STRIPING_BAND5 = "NONE"<br>
STRIPING_BAND61 = "NONE"<br> STRIPING_BAND62 = "NONE"<br> STRIPING_BAND7 = "NONE"<br> STRIPING_BAND8 = "NONE"<br> BANDING = "N"<br> COHERENT_NOISE = "Y"<br>
MEMORY_EFFECT = "N"<br> SCAN_CORRELATED_SHIFT = "N"<br> INOPERABLE_DETECTORS = "N"<br> DROPPED_LINES = "N"<br> END_GROUP = CORRECTIONS_APPLIED<br> GROUP = PROJECTION_PARAMETERS<br>
REFERENCE_DATUM = "WGS84"<br> REFERENCE_ELLIPSOID = "WGS84"<br> GRID_CELL_SIZE_PAN = 15.000<br> GRID_CELL_SIZE_THM = 30.000<br> GRID_CELL_SIZE_REF = 30.000<br> ORIENTATION = "NUP"<br>
RESAMPLING_OPTION = "CC"<br> MAP_PROJECTION = "UTM"<br> END_GROUP = PROJECTION_PARAMETERS<br> GROUP = UTM_PARAMETERS<br> ZONE_NUMBER = 54<br> END_GROUP = UTM_PARAMETERS<br>END_GROUP = L1_METADATA_FILE<br>
END<br><br></font>When I perform a GDALINFO on the GeoTiff file, I get this report:<br><font style="font-family: courier new,monospace;" size="1">Driver: GTiff/GeoTIFF<br>Files: L71095085_08520020923_B10.TIF<br>Size is 8321, 7261<br>
Coordinate System is:<br>PROJCS["WGS 84 / UTM zone 54N",<br> GEOGCS["WGS 84",<br> DATUM["WGS_1984",<br> SPHEROID["WGS 84",6378137,298.257223563,<br> AUTHORITY["EPSG","7030"]],<br>
AUTHORITY["EPSG","6326"]],<br> PRIMEM["Greenwich",0],<br> UNIT["degree",0.0174532925199433],<br> AUTHORITY["EPSG","4326"]],<br>
PROJECTION["Transverse_Mercator"],<br>
PARAMETER["latitude_of_origin",0],<br> PARAMETER["central_meridian",141],<br> PARAMETER["scale_factor",0.9996],<br> PARAMETER["false_easting",500000],<br> PARAMETER["false_northing",0],<br>
UNIT["metre",1,<br> AUTHORITY["EPSG","9001"]],<br> AUTHORITY["EPSG","32654"]]<br>Origin = (440699.999999999940000,-3881100.000000000000000)<br>Pixel Size = (30.000000000000000,-30.000000000000000)<br>
Metadata:<br> AREA_OR_POINT=Point<br>Image Structure Metadata:<br> INTERLEAVE=BAND<br>Corner Coordinates:<br>Upper Left ( 440700.000,-3881100.000) (140d20'58.53"E, 35d 4'15.27"S)<br>Lower Left ( 440700.000,-4098930.000) (140d19'59.63"E, 37d 2'4.93"S)<br>
Upper Right ( 690330.000,-3881100.000) (143d 5'13.21"E, 35d 3'16.90"S)<br>Lower Right ( 690330.000,-4098930.000) (143d 8'22.06"E, 37d 1'2.23"S)<br>Center ( 565515.000,-3990015.000) (141d43'38.60"E, 36d 3'8.96"S)<br>
Band 1 Block=8321x1 Type=Byte, ColorInterp=Gray</font><br><br>As you can see the lower right Y should be -4098900, but GDALINFO reports ,-4098930<br><br>My question is:<br>Is this the correct behavior of GDAL or do we misinterpreted it?<br>
<br><span style="color: black;"><div dir="ltr"><div><span style="font-family: arial,helvetica,sans-serif;">Thanks,<br><br>Paul<br><br>--</span><br style="font-family: arial,helvetica,sans-serif;"><span style="font-family: arial,helvetica,sans-serif;">Paul Meems</span><br style="font-family: arial,helvetica,sans-serif;">
<span style="font-family: arial,helvetica,sans-serif;">Release manager, configuration manager</span><br style="font-family: arial,helvetica,sans-serif;"><span style="font-family: arial,helvetica,sans-serif;">and forum
moderator of MapWindow GIS.</span><br style="font-family: arial,helvetica,sans-serif;"><a href="http://www.mapwindow.org/"><span style="font-family: arial,helvetica,sans-serif;">www.mapwindow.org</span></a><br style="font-family: arial,helvetica,sans-serif;">
<span style="font-family: arial,helvetica,sans-serif;"></span></div><br></div></span><br>