NAME
gdalwarp - gdalwarp image reprojection and warping utility
SYNOPSIS
gdalwarp [--help-general] [--formats]
[-s_srs srs_def] [-t_srs srs_def] [-to "NAME=VALUE"]
[-order n] [-tps] [-rpc] [-geoloc] [-et err_threshold]
[-te xmin ymin xmax ymax] [-tr xres yres] [-ts width height]
[-wo "NAME=VALUE"] [-ot Byte/Int16/...] [-wt Byte/Int16]
[-srcnodata "value [value...]"] [-dstnodata "value [value...]"] -dstalpha
[-r resampling_method] [-wm memory_in_mb] [-multi] [-q]
[-cutline datasource] [-cl layer] [-cwhere expression]
[-csql statement] [-cblend dist_in_pixels]
[-of format] [-co "NAME=VALUE"]*
srcfile* dstfile
DESCRIPTION
The gdalwarp utility is an image mosaicing, reprojection and warping
utility. The program can reproject to any supported projection, and can
also apply GCPs stored with the image if the image is ’raw’ with
control information.
-s_srs srs def:
source spatial reference set. The coordinate systems that can be
passed are anything supported by the
OGRSpatialReference.SetFromUserInput() call, which includes EPSG
PCS and GCSes (ie. EPSG:4296), PROJ.4 declarations (as above), or
the name of a .prf file containing well known text.
-t_srs srs_def:
target spatial reference set. The coordinate systems that can be
passed are anything supported by the
OGRSpatialReference.SetFromUserInput() call, which includes EPSG
PCS and GCSes (ie. EPSG:4296), PROJ.4 declarations (as above), or
the name of a .prf file containing well known text.
-to NAME=VALUE:
set a transformer option suitable to pass to
GDALCreateGenImgProjTransformer2().
-order n:
order of polynomial used for warping (1 to 3). The default is to
select a polynomial order based on the number of GCPs.
-tps:
Force use of thin plate spline transformer based on available GCPs.
-rpc:
Force use of RPCs.
-geoloc:
Force use of Geolocation Arrays.
-et err_threshold:
error threshold for transformation approximation (in pixel units -
defaults to 0.125).
-te xmin ymin xmax ymax:
set georeferenced extents of output file to be created (in target
SRS).
-tr xres yres:
set output file resolution (in target georeferenced units)
-ts width height:
set output file size in pixels and lines
-wo NAME=VALUE:
Set a warp options. The GDALWarpOptions::papszWarpOptions docs show
all options. Multiple -wo options may be listed.
-ot type:
For the output bands to be of the indicated data type.
-wt type:
Working pixel data type. The data type of pixels in the source
image and destination image buffers.
-r resampling_method:
Resampling method to use. Available methods are:
near:
nearest neighbour resampling (default, fastest algorithm, worst
interpolation quality).
bilinear:
bilinear resampling.
cubic:
cubic resampling.
cubicspline:
cubic spline resampling.
lanczos:
Lanczos windowed sinc resampling.
-srcnodata value [value...]:
Set nodata masking values for input bands (different values can be
supplied for each band). If more than one value is supplied all
values should be quoted to keep them together as a single operating
system argument. Masked values will not be used in interpolation.
Use a value of None to ignore intrinsic nodata settings on the
source dataset.
-dstnodata value [value...]:
Set nodata values for output bands (different values can be
supplied for each band). If more than one value is supplied all
values should be quoted to keep them together as a single operating
system argument. New files will be initialized to this value and if
possible the nodata value will be recorded in the output file.
-dstalpha:
Create an output alpha band to identify nodata (unset/transparent)
pixels.
-wm memory_in_mb:
Set the amount of memory (in megabytes) that the warp API is
allowed to use for caching.
-multi:
Use multithreaded warping implementation. Multiple threads will be
used to process chunks of image and perform input/output operation
simultaneously.
-q:
Be quiet.
-of format:
Select the output format. The default is GeoTIFF (GTiff). Use the
short format name.
-co NAME=VALUE:
passes a creation option to the output format driver. Multiple -co
options may be listed. See format specific documentation for legal
creation options for each format.
-cutline datasource:
Enable use of a blend cutline from the name OGR support datasource.
-cl layername:
Select the named layer from the cutline datasource.
-cwhere expression:
Restrict desired cutline features based on attribute query.
-csql query:
Select cutline features using an SQL query instead of from a layer
with -cl.
-cblend distance:
Set a blend distance to use to blend over cutlines (in pixels).
srcfile:
The source file name(s).
dstfile:
The destination file name.
Mosaicing into an existing output file is supported if the output file
already exists. The spatial extent of the existing file will not be
modified to accomodate new data, so you may have to remove it in that
case.
Polygon cutlines may be used to restrict the the area of the
destination file that may be updated, including blending. Cutline
features must be in the georeferenced units of the destination file.
EXAMPLE
For instance, an eight bit spot scene stored in GeoTIFF with control
points mapping the corners to lat/long could be warped to a UTM
projection with a command like this:
gdalwarp -t_srs ’+proj=utm +zone=11 +datum=WGS84’ raw_spot.tif utm11.tif
For instance, the second channel of an ASTER image stored in HDF with
control points mapping the corners to lat/long could be warped to a UTM
projection with a command like this:
gdalwarp HDF4_SDS:ASTER_L1B:"pg-PR1B0000-2002031402_100_001":2 pg-PR1B0000-2002031402_100_001_2.tif
AUTHOR
Frank Warmerdam <warmerdam@pobox.com>, Silke Reimer
<silke@intevation.de>