NAME

       gdal_merge - Mosaics a set of images.

SYNOPSIS

          gdal_merge.py [-o out_filename] [-of out_format] [-co NAME=VALUE]*
                        [-ps pixelsize_x pixelsize_y] [-tap] [-separate] [-q] [-v] [-pct]
                        [-ul_lr ulx uly lrx lry] [-init "value [value...]"]
                        [-n nodata_value] [-a_nodata output_nodata_value]
                        [-ot datatype] [-createonly] input_files

DESCRIPTION

       This  utility  will  automatically mosaic a set of images.  All the images must be in the same coordinate
       system and have a matching number of bands, but they may be overlapping, and at different resolutions. In
       areas of overlap, the last image will be copied over earlier ones.

       -o <out_filename>
              The name of the output file, which will be created if it  does  not  already  exist  (defaults  to
              "out.tif").

       -of <format>
              Select the output format. Starting with GDAL 2.3, if not specified, the format is guessed from the
              extension (previously was GTiff). Use the short format name.

       -co <NAME=VALUE>
              Many  formats  have  one or more optional creation options that can be used to control particulars
              about the file created. For instance, the GeoTIFF driver  supports  creation  options  to  control
              compression, and whether the file should be tiled.

              The  creation  options  available  vary by format driver, and some simple formats have no creation
              options at all. A list of options supported for a format can be listed with the --formats  command
              line option but the documentation for the format is the definitive source of information on driver
              creation options.  See raster_drivers format specific documentation for legal creation options for
              each format.

       -ot <type>
              Force  the  output  image bands to have a specific data type supported by the driver, which may be
              one of the following: Byte, UInt16,  Int16,  UInt32,  Int32,  Float32,  Float64,  CInt16,  CInt32,
              CFloat32 or CFloat64.

       -ps <pixelsize_x> <pixelsize_y>
              Pixel  size  to  be  used for the output file.  If not specified the resolution of the first input
              file will be used.

       -tap   (target aligned pixels) align the coordinates of the extent of the output file to  the  values  of
              the -tr, such that the aligned extent includes the minimum extent.

       -ul_lr <ulx> <uly> <lrx> <lry>
              The extents of the output file.  If not specified the aggregate extents of all input files will be
              used.

       -v     Generate verbose output of mosaicing operations as they are done.

       -separate
              Place each input file into a separate band.

       -pct   Grab  a  pseudo-color  table  from  the  first  input  image,  and use it for the output.  Merging
              pseudo-colored images this way assumes that all input files use the same color table.

       -n <nodata_value>
              Ignore pixels from files being merged in with this pixel value.

       -a_nodata <output_nodata_value>
              Assign a specified nodata value to output bands.

       -init <"value(s)">
              Pre-initialize the output image bands with these values.  However, it is not marked as the  nodata
              value in the output file.  If only one value is given, the same value is used in all the bands.

       -createonly
              The  output  file  is  created (and potentially pre-initialized) but no input image data is copied
              into it.

       NOTE:
          gdal_merge.py is a Python script, and will only work if GDAL was built with Python support.

EXAMPLE

       Create an image with the pixels in all bands initialized to 255.

          gdal_merge.py -init 255 -o out.tif in1.tif in2.tif

       Create an RGB image that shows blue in pixels with no data. The first two bands will be initialized to  0
       and the third band will be initialized to 255.

          gdal_merge.py -init "0 0 255" -o out.tif in1.tif in2.tif

AUTHOR

       Frank Warmerdam <warmerdam@pobox.com>, Silke Reimer <silke@intevation.de>

COPYRIGHT

       1998-2021

                                                  Dec 27, 2021                                     GDAL_MERGE(1)