QUOTE (djellison @ Jan 21 2015, 03:56 AM)
INTERCHANGE_FORMAT = BINARY
O.k., it's binary...
QUOTE (djellison @ Jan 21 2015, 03:56 AM)
LINES = 8641
LINE_SAMPLES = 17281
...17281 by 8641 sample points...
QUOTE (djellison @ Jan 21 2015, 03:56 AM)
SAMPLE_BITS = 32
...4 bytes per sample, which would be either standard-precision float or int...
QUOTE (djellison @ Jan 21 2015, 03:56 AM)
MINIMUM = -21527
MAXIMUM = 19005
Obviously, the sample values range from -21527 to 19005 metres relative to the rotation ellipsoid - which means that they are in fact integer! But why do they use signed int rather than signed short int? And which bit order - big oder small endian?
QUOTE (djellison @ Jan 21 2015, 03:56 AM)
A_AXIS_RADIUS = 255.0
B_AXIS_RADIUS = 255.0
C_AXIS_RADIUS = 255.0
...the underlying ellipsoid, here a perfect sphere...
QUOTE (djellison @ Jan 21 2015, 03:56 AM)
MAP_PROJECTION_TYPE = SIMPLE_CYLINDRICAL
...so spacing of points can be calculated from the x and y dimensions of the data array...
QUOTE (djellison @ Jan 21 2015, 03:56 AM)
SAMPLE_PROJECTION_OFFSET = 8640.0
Is this a value to be added to or subtracted from the sample values?
QUOTE (djellison @ Jan 21 2015, 03:56 AM)
MISSING_CONSTANT = -32768
Missing data code...
QUOTE (djellison @ Jan 21 2015, 03:56 AM)
That data is enough to open it as a raw file in Photoshop, Gimp or ImageJ etc. and then use it as a displacement map on a mesh.
When I try to open it, I just get a strange noisy thing which, when zoomed in, appears like vague rastered interference shapes...
perhaps I better should try writing a C++ program which extracts the sample data and stores them as an uncompressed TGA image file!
See you in Khyberspace!
Yadgar