dwww Home | Manual pages | Find package

i.in.spotvgt(1grass)        GRASS GIS User's Manual       i.in.spotvgt(1grass)

NAME
       i.in.spotvgt  - Imports SPOT VGT NDVI data into a raster map.

KEYWORDS
       imagery, import, NDVI, SPOT

SYNOPSIS
       i.in.spotvgt
       i.in.spotvgt --help
       i.in.spotvgt  [-a]  input=name  [output=name]   [--overwrite]  [--help]
       [--verbose]  [--quiet]  [--ui]

   Flags:
       -a
           Also import quality map (SM status map layer) and filter NDVI map

       --overwrite
           Allow output files to overwrite existing files

       --help
           Print usage summary

       --verbose
           Verbose module output

       --quiet
           Quiet module output

       --ui
           Force launching GUI dialog

   Parameters:
       input=name [required]
           Name of input SPOT VGT NDVI HDF file

       output=name
           Name for output raster map

DESCRIPTION
       i.in.spotvgt imports SPOT Vegetation (1km, global) NDVI data sets.  Af-
       ter  import  the  digital  numbers (DN) are remapped to VEGETATION NDVI
       values and the NDVI color table is applied. The imported DN map is  re-
       moved after remapping.

       Apparently  missing  raster  cells  due to bad pixel quality are recon-
       structed by the SPOT operating team in the NDVI file.  The  differences
       between the filtered (-a flag) and raw NDVI map should be compared.

NOTES
       The  SPOT VGT files are delivered in HDF4 (Hierarchical Data Format Re-
       lease 4) format. It is required to have the  GDAL  libraries  installed
       with HDF4 support.

   Export of entire world SPOT VGT maps
       When  working with SPOT VGT with entire world extent, it is recommended
       to zoom to w=180W and e=180E instead of using the map  extent  for  map
       export.  These  entire  world SPOT VGT data are exceeding -180.0 degree
       which can lead to unhelpful large East-West coordinates in the exported
       file.  It  is  also recommended to then use an export command which re-
       spects the user settings. Example:
       # import:
       i.in.spotvgt 0001_NDV.HDF
       # export:
       g.region w=180W e=180E n=75:00:16.071429N s=56:00:16.069919S res=0:00:32.142857 -p
       r.out.gdal 0001_NDV format=GTiff out=spotndvi.tif

SEE ALSO
        r.in.gdal, r.out.gdal

REFERENCES
       SPOT Vegetation (1km, global) NDVI data set server
       SPOT Vegetation FAQ
       1.13 How must I read the 8 bits of the status map? - Quality map

AUTHOR
       Markus Neteler

SOURCE CODE
       Available at: i.in.spotvgt source code (history)

       Accessed: unknown

       Main index | Imagery index | Topics index | Keywords index |  Graphical
       index | Full index

       © 2003-2022 GRASS Development Team, GRASS GIS 7.8.7 Reference Manual

GRASS 7.8.7                                               i.in.spotvgt(1grass)

Generated by dwww version 1.14 on Sun Dec 29 18:13:02 CET 2024.