NAME

       gdalcompare -  Compare two images.

SYNOPSIS

          gdalcompare [--help] [--help-general]
                         [-dumpdiffs] [-skip_binary] [-skip_overviews]
                         [-skip_geolocation] [-skip_geotransform]
                         [-skip_metadata] [-skip_rpc] [-skip_srs]
                         [-sds] <golden_file> <new_file>

DESCRIPTION

       gdalcompare  compares  two  GDAL supported datasets and reports the differences. In addition to reporting
       differences to the standard output the script will also return the difference count in its exit value.

       Image pixels, and various metadata are checked. There is also a byte by byte comparison done  which  will
       count  as one difference. So if it is only important that the GDAL visible data is identical a difference
       count of 1 (the binary difference) should be considered acceptable.

       NOTE:
          gdalcompare is a Python utility, and is only available if GDAL Python bindings are available.

       --help Show this help message and exit

       --help-general
              Gives a brief usage message for the generic GDAL commandline options and exit.

       -dumpdiffs
              New in version 3.8.

              Whether to output the difference in pixel content in a TIFF file in the current directory.

       -skip_binary
              New in version 3.8.

              Whether to skip exact comparison of binary content.

       -skip_overviews
              New in version 3.8.

              Whether to skip comparison of overviews.

       -skip_geolocation
              New in version 3.8.

              Whether to skip comparison of GEOLOCATION metadata domain.

       -skip_geotransform
              New in version 3.8.

              Whether to skip comparison of geotransform matrix.

       -skip_metadata
              New in version 3.8.

              Whether to skip comparison of metadata

       -skip_rpc
              New in version 3.8.

              Whether to skip comparison of Rational Polynomial Coefficients (RPC) metadata domain.

       -skip_srs
              New in version 3.8.

              Whether to skip comparison of spatial reference systems (SRS).

       -sds   If this flag is passed the script will compare all subdatasets  that  are  part  of  the  dataset,
              otherwise subdatasets are ignored.

       <golden_file>
              The file that is considered correct, referred to as the golden file.

       <new_file>
              The file being compared to the golden file, referred to as the new file.

       Note that the gdalcompare script (like all the other scripts) can also be called as a library from python
       code:  from  osgeo_utils  import  gdalcompare.  The primary entry point is gdalcompare.compare_db() which
       takes a golden gdal.Dataset and a new gdal.Dataset as arguments and returns a difference count (excluding
       the binary comparison). The gdalcompare.compare_sds() entry point can be used to compare subdatasets.

EXAMPLES

          gdalcompare -dumpdiffs N.tiff S.tiff; echo $?
          Files differ at the binary level.
          Band 1 checksum difference:
            Golden: 36694
            New:    40645
            Pixels Differing: 1509
            Maximum Pixel Difference: 255.0
            Wrote Diffs to: 1.tif
          Differences Found: 2
          2

          gdalcompare N.tiff N.tiff; echo $?
          Differences Found: 0
          0

AUTHOR

       Frank Warmerdam <warmerdam@pobox.com>

COPYRIGHT

       1998-2025

                                                  Apr 01, 2025                                    GDALCOMPARE(1)