i.landsat.import

Imports Landsat satellite data downloaded using i.landsat.download.

i.landsat.import [-rlop] input=name [unzip_dir=name] [pattern=string] [pattern_file=string] [extent=string] [resample=string] [memory=integer] [register_output=name] [--overwrite] [--verbose] [--quiet] [--qq] [--ui]

Example:

i.landsat.import input=name

grass.script.run_command("i.landsat.import", input, unzip_dir=None, pattern=None, pattern_file=None, extent="input", resample="nearest", memory=300, register_output=None, flags=None, overwrite=False, verbose=False, quiet=False, superquiet=False)

Example:

gs.run_command("i.landsat.import", input="name")

Parameters

Command linePython (grass.script)

input=name [required]
    Name of input directory with downloaded Landsat data
unzip_dir=name
    Name of directory into which Landsat zip-files are extracted (default=input)
pattern=string
    Band name pattern to import
pattern_file=string
    File name pattern to import
extent=string
    Output raster map extent
    Allowed values: input, region
    Default: input
    input: extent of input map
    region: extent of current region
resample=string
    Resampling method to use for reprojection
    Allowed values: nearest, bilinear, bicubic, lanczos, bilinear_f, bicubic_f, lanczos_f
    Default: nearest
    nearest: nearest neighbor
    bilinear: bilinear interpolation
    bicubic: bicubic interpolation
    lanczos: lanczos filter
    bilinear_f: bilinear interpolation with fallback
    bicubic_f: bicubic interpolation with fallback
    lanczos_f: lanczos filter with fallback
memory=integer
    Maximum memory to be used (in MB)
    Cache size for raster rows
    Default: 300
register_output=name
    Name for output file to use with t.register
-r
    Reproject raster data using r.import if needed
-l
    Link raster data instead of importing
-o
    Override projection check (use current location's projection)
-p
    Print raster data to be imported and exit
--overwrite
    Allow output files to overwrite existing files
--help
    Print usage summary
--verbose
    Verbose module output
--quiet
    Quiet module output
--qq
    Very quiet module output
--ui
    Force launching GUI dialog

input : str, required
    Name of input directory with downloaded Landsat data
    Used as: input, dir, name
unzip_dir : str, optional
    Name of directory into which Landsat zip-files are extracted (default=input)
    Used as: input, dir, name
pattern : str, optional
    Band name pattern to import
pattern_file : str, optional
    File name pattern to import
extent : str, optional
    Output raster map extent
    Allowed values: input, region
    input: extent of input map
    region: extent of current region
    Default: input
resample : str, optional
    Resampling method to use for reprojection
    Allowed values: nearest, bilinear, bicubic, lanczos, bilinear_f, bicubic_f, lanczos_f
    nearest: nearest neighbor
    bilinear: bilinear interpolation
    bicubic: bicubic interpolation
    lanczos: lanczos filter
    bilinear_f: bilinear interpolation with fallback
    bicubic_f: bicubic interpolation with fallback
    lanczos_f: lanczos filter with fallback
    Default: nearest
memory : int, optional
    Maximum memory to be used (in MB)
    Cache size for raster rows
    Default: 300
register_output : str, optional
    Name for output file to use with t.register
    Used as: output, file, name
flags : str, optional
    Allowed values: r, l, o, p
    r
        Reproject raster data using r.import if needed
    l
        Link raster data instead of importing
    o
        Override projection check (use current location's projection)
    p
        Print raster data to be imported and exit
overwrite: bool, optional
    Allow output files to overwrite existing files
    Default: False
verbose: bool, optional
    Verbose module output
    Default: False
quiet: bool, optional
    Quiet module output
    Default: False
superquiet: bool, optional
    Very quiet module output
    Default: False

DESCRIPTION

The i.landsat.import module allows importing Landsat 5, 7 and 8 products downloaded by the i.landsat.download module.

By default i.landsat.import imports all Landsat bands within the scene files found in the input directory. The number of scene files can be optionally reduced with the pattern_file option. In this option, a regular expression for filtering the file names can be given, e.g. '229083' for importing only scenes from path 229 and row 083.

By default i.landsat.import imports the full scene. Optionally, the import can be reduced to the computational region extent with extent=region.

Note that in case that the spatial reference system of the input data differs from that of the GRASS GIS target location, the input data will be reprojected internally by means of r.import. To speed up this process, a higher than default value can be specified for the memory option.

If the user wants to ignore an insignificant mismatch in the spatial reference system, the projection check can be suppressed with the -o flag and data will be imported directly.

Alternatively, input data can be linked by means of r.external using -l flag. Note that linking data requires that Landsat input data and GRASS location have the same spatial reference system (e.g., the same UTM zone). Take into account that USGS provides all Landsat products in UTM north zones whether they belong to North or South Hemisphere.

The number of Landsat bands to be imported can be optionally reduced by the pattern option. Below an overview of Landsat 5 TM, 7 ETM and 8 OLI band's spatial resolution:

Spatial resolution [m]	L5 Bands	L7 Bands	L8 Bands
15	--	B8	B8
30	B1, B2, B3, B4, B5, B7	B1, B2, B3, B4, B5, B7	B1, B2, B3, B4, B5, B6, B7, B9
60	--	B6	--
100	--	--	B10, B11
120	B6	--	--

Note that while the original resolution of band 6 in Landsat 5 TM and Landsat 7 ETM is 120 and 60 m respectively, they are provided with a resampled resolution of 30 m. For further details about bands wavelength and scene size, visit the band designations page at USGS website.

The file naming convention for Landsat scenes is found here.

With the register_output option i.landsat.import allows to create a text file that can be used to register imported imagery data into a space-time raster dateset (STRDS) by means of t.register. A register file typically contains 2 or 3 columns with the map name and start time or the map name plus start and end time in the case of interval time type. Landsat data is considered to be of instance time type, i.e., we only have one point in time. Hence, the output register file will contain the map name and start time separated by | when using GRASS GIS stable version. In the case of GRASS GIS development version which supports the band reference concept (see i.band.library module for details), the output register file is extended by a third column containing the band reference information, see the examples below.

EXAMPLES

List Landsat bands to import

At first, print the list of raster files to be imported by -p. For each file also projection match with current location is printed including detected input data EPSG code:

i.landsat.import -p input=data

Import Landsat data

Limit import to only 4th and 5th bands:

i.landsat.import input=data pattern='B(4|5)'

Limit import to all bands with 30m resolution:

i.landsat.import input=data pattern='B(1|2|3|4|5|6|7|9)'

Link Landsat data:

i.landsat.import -l input=data

Link data from specific path and row while ignoring projection check

i.landsat.import -l -o input=data pattern_file='229083'

Limit import to bands 4 and 5 for path 229 and row 083 in 2019

i.landsat.import input=data pattern_file='229083_2019' pattern='B(4|5)'

Limit import to optical, NIR, thermal and QA_PIXEL using a regular expression (Landsat-8):

i.landsat.import input=data pattern='(B(2|3|4|5|6|7|8|10|11)|QA_PIXEL)'

Limit import to bands 4 and 5 for path 229 and row 083 in 2019 and get a txt file to use in t.register

i.landsat.import input=data pattern_file='229083_2019' pattern='B(4|5)' \
    register_output=t_register.txt

# create a STRDS and register imported data
t.create output=landsat_ts title="Landsat 8 time series" \
    description="Landsat 8 data, path-row 229-83, year 2020"
t.register input=landsat_ts file=t_register.txt

AUTHOR

Veronica Andreo, CONICET, Argentina.

SOURCE CODE

Available at: i.landsat.import source code (history)
Latest change: Thursday Feb 20 13:02:26 2025 in commit 53de819