Due to the lapse in federal government funding, NASA is not updating this website. We sincerely regret this inconvenience.

 

LVIS Data Structure (LDS) Version 1.02 Description

Version: 1.02

Date Created: 2006/04/17


Byte Order:

  • All data items are Big Endian unless otherwise noted.

Reference Frame:

  • International Terrestrial Reference Frame (ITRF 2000) / WGS-84 Ellipsoid).

General Notes:

  • A release is comprised of two or more file types sharing a common origin. All files within the release have equal record numbers, and correspond to one another laser shot for shot. (i.e. record 1000 in the .lge file will be the same laser shot as record 1000 in the .lce file for a given data set)

Level2 LVIS Canopy Elevation (.LCE) File Description:

Item Byte Size Format Units Item Description
LFID 4 unsigned longword integer LVIS file identification
shotnumber 4 unsigned longword integer laser shot assigned during collection
time 8 double precision floating point seconds UTC decimal seconds of the day
tlon 8 double precision floating point degrees longitude of the highest detected return (degrees east)
tlat 8 double precision floating point degrees latitude of the highest detected return (degrees north)
zt 4 single precision floating point meters elevation of the highest detected return (i.e., zg + rh100 see here)
TOTAL 36 bytes per record


Level2 LVIS Ground Elevation (.LGE) File Description:

Item Byte Size Format Units Item Description
LFID 4 unsigned longword integer LVIS file identification
shotnumber 4 unsigned longword integer laser shot assigned during collection
time 8 double precision floating point seconds UTC decimal seconds of the day
glon 8 double precision floating point degrees longitude of the lowest detected mode within the waveform (degrees east)
glat 8 double precision floating point degrees latitude of the lowest detected mode within the waveform (degrees north)
zg 4 single precision floating point meters mean elevation of the lowest detected mode within the waveform (see here)
RH25 4 single precision floating point meters height (relative to zg) at which 25% of the waveform energy occurs (see here)
RH50 4 single precision floating point meters height (relative to zg) at which 50% of the waveform energy occurs (see here)
RH75 4 single precision floating point meters height (relative to zg) at which 75% of the waveform energy occurs (see here)
RH100 4 single precision floating point meters height (relative to zg) at which 100% of the waveform energy occurs (see here)
TOTAL 52 bytes per record


Level1b LVIS Geolocated Waveform (.LGW) File Description:

Item Byte Size Format Units Item Description
LFID 4 unsigned longword integer LVIS file identification
shotnumber 4 unsigned longword integer laser shot assigned during collection
time 8 double precision floating point seconds UTC decimal seconds of the day
lon0 8 double precision floating point degrees longitude of the highest sample of the waveform (degrees east)
lat0 8 double precision floating point degrees latitude of the highest sample of the waveform (degrees north)
z0 4 single precision floating point meters elevation of the highest sample of the waveform
lon431 8 double precision floating point degrees longitude of the lowest sample of the waveform (degrees east)
lat431 8 double precision floating point degrees latitude of the lowest sample of the waveform (degrees north)
z431 4 single precision floating point meters elevation of the lowest sample of the waveform
sigmean 4 single precision floating point counts signal mean noise level, calculated in-flight
wave 432 byte counts return waveform, recorded in-flight
TOTAL 492 bytes per record