Export World Wind .hdr & .blw files...
sdw
Global Mapper User
Just trying to understand this to cross reference elevation tile replacement. If I ask for "ADVANCED: Create World File for Exported Tiles" while doing an "Export Web Format..." / "World Wind Tiles" it generates in addition to the .BIL, .STX and .HDR files a .BLW file. Looking at the metafiles for one of these tiles:
m:>type 3094_1319.blw
0.00029296875000000
0.00000000000000000
0.00000000000000000
-0.00029296875000000
-122.03598632812501000
46.01059570312499900
m:>type 3094_1319.hdr
BYTEORDER M
LAYOUT BIL
NROWS 150
NCOLS 150
NBANDS 1
NBITS 16
BANDROWBYTES 300
TOTALROWBYTES 300
BANDGAPBYTES 0
NODATA -32767
ULXMAP -122.0361328125
ULYMAP 46.0107421875
XDIM 0.00029493498322148
YDIM 0.00029493498322148
I thought that the first and fourth rows of the BLW should match the HDR.XDIM and -YDIM values respectively. Also that the last two lines of the BLW should have matched HDR.ULXMAP and ULYMAP?
The source elevation is NED 1/3 data reprojected to WGS84 but I see similar results if left in NAD83 using the export command. Are these two metafiles using different projections or something like that?
This is in Global Mapper v13.2.0 64bit on Win7
m:>type 3094_1319.blw
0.00029296875000000
0.00000000000000000
0.00000000000000000
-0.00029296875000000
-122.03598632812501000
46.01059570312499900
m:>type 3094_1319.hdr
BYTEORDER M
LAYOUT BIL
NROWS 150
NCOLS 150
NBANDS 1
NBITS 16
BANDROWBYTES 300
TOTALROWBYTES 300
BANDGAPBYTES 0
NODATA -32767
ULXMAP -122.0361328125
ULYMAP 46.0107421875
XDIM 0.00029493498322148
YDIM 0.00029493498322148
I thought that the first and fourth rows of the BLW should match the HDR.XDIM and -YDIM values respectively. Also that the last two lines of the BLW should have matched HDR.ULXMAP and ULYMAP?
The source elevation is NED 1/3 data reprojected to WGS84 but I see similar results if left in NAD83 using the export command. Are these two metafiles using different projections or something like that?
This is in Global Mapper v13.2.0 64bit on Win7
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