On Tue, 18 Jan 2011 09:10:15 +0200, clipka <ano### [at] anonymousorg> wrote:
> Am 17.01.2011 20:52, schrieb Nekar Xenos:
>> "Height files have the extension .HGT and are signed two byte integers.
>> bytes are in Motorola "big-endian" order with the most significant byte
>> directly readable by systems such as Sun SPARC, Silicon Graphics and
>> DEC Alpha and most PCs use Intel ("little-endian") order so some
>> may be necessary. Heights are in meters referenced to the WGS84 geoid.
>> voids are assigned the value -32768."
> That's pretty meager; some information would be needed about the number
> of columns & rows, and how this format deals with the spheroid shape of
from http://www2.jpl.nasa.gov/srtm/faq.html :
"The SRTM data files have names like "N34W119.hgt". What do the letters
and numbers refer to, and what is ".hgt" format?
Each data file covers a one-degree-of-latitude by one-degree-of-longitude
block of Earth's surface. The first seven characters indicate the
southwest corner of the block, with N, S, E, and W referring to north,
south, east, and west. Thus, the "N34W119.hgt" file covers latitudes 34 to
35 North and longitudes 118-119 West (this file includes downtown Los
Angeles, California). The filename extension ".hgt" simply stands for the
word "height", meaning elevation. It is NOT a format type. These files are
in "raw" format (no headers and not compressed), 16-bit signed integers,
elevation measured in meters above sea level, in a "geographic" (latitude
and longitude array) projection, with data voids indicated by -32768.
International 3-arc-second files have 1201 columns and 1201 rows of data,
with a total filesize of 2,884,802 bytes ( = 1201 x 1201 x 2). United
States 1-arc-second files have 3601 columns and 3601 rows of data, with a
total filesize of 25,934,402 bytes ( = 3601 x 3601 x 2). For more
information read the text file "SRTM_Topo.txt" at
"The spoon is not real"
Post a reply to this message