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Image-ExifTool
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<span class=com>#------------------------------------------------------------------------------
# File:         example.config  --&gt;  ~/.ExifTool_config
#
# Description:  Example user configuration file for Image::ExifTool
#
# Notes:        This example file shows how to define your own shortcuts and
#               add new EXIF, IPTC, XMP, PNG, MIE and Composite tags, as well
#               as how to specify preferred lenses for the LensID tag, and
#               define new file types and default ExifTool API options and
#               command-line arguments.
#
#               Note that unknown tags may be extracted even if they aren't
#               defined, but tags must be defined to be written.  Also note
#               that it is possible to override an existing tag definition
#               with a user-defined tag.
#
#               To activate this file, rename it to ".ExifTool_config" and
#               place it in your home directory or the exiftool application
#               directory.  (On Mac and some Windows systems this must be done
#               via the command line since the GUI's may not allow filenames to
#               begin with a dot.  Use the "rename" command in Windows or "mv"
#               on the Mac.)  This causes ExifTool to automatically load the
#               file when run.  Your home directory is determined by the first
#               defined of the following environment variables:
#
#                   1.  EXIFTOOL_HOME
#                   2.  HOME
#                   3.  HOMEDRIVE + HOMEPATH
#                   4.  (the current directory)
#
#               Alternatively, the -config option of the exiftool application
#               may be used to load a specific configuration file (note that
#               this must be the first option on the command line):
#
#                   exiftool -config example.config ...
#
#               This example file defines the following 16 new tags as well as
#               a number of Shortcut and Composite tags:
#
#                   1.  EXIF:NewEXIFTag
#                   2.  GPS:GPSPitch
#                   3.  GPS:GPSRoll
#                   4.  IPTC:NewIPTCTag
#                   5.  XMP-xmp:NewXMPxmpTag
#                   6.  XMP-exif:GPSPitch
#                   7.  XMP-exif:GPSRoll
#                   8.  XMP-xxx:NewXMPxxxTag1
#                   9.  XMP-xxx:NewXMPxxxTag2
#                  10.  XMP-xxx:NewXMPxxxTag3
#                  11.  XMP-xxx:NewXMPxxxStruct
#                  12.  PNG:NewPngTag1
#                  13.  PNG:NewPngTag2
#                  14.  PNG:NewPngTag3
#                  15.  MIE-Meta:NewMieTag1
#                  16.  MIE-Test:NewMieTag2
#
#               For detailed information on the definition of tag tables and
#               tag information hashes, see lib/Image/ExifTool/README.
#------------------------------------------------------------------------------

<a name='Shortcuts'># Shortcut tags are used when extracting information to simplify
# commonly used commands.  They can be used to represent groups
# of tags, or to provide an alias for a tag name.</a></span>
%Image::ExifTool::UserDefined::Shortcuts = (
    MyShortcut =&gt; ['exif:createdate','exposuretime','aperture'],
    MyAlias =&gt; 'FocalLengthIn35mmFormat',
);

<span class=com># NOTE: All tag names used in the following tables are case sensitive.

<a name='UserDefined'># The %Image::ExifTool::UserDefined hash defines new tags to be added
# to existing tables.</a></span>
%Image::ExifTool::UserDefined = (
    <span class=com># All EXIF tags but GPS are added to the Main table, and WriteGroup is
    # used to specify where the tag is written (defaulting to ExifIFD). Note
    # that when reading custom EXIF tags, the same config file must be used
    # to be able to see them with the given names. Without the config file
    # they may only be seen as unknown tags with the -u option.</span>
    'Image::ExifTool::Exif::Main' =&gt; {
        <span class=com># Example 1.  EXIF:NewEXIFTag</span>
        0xd000 =&gt; {
            Name =&gt; 'NewEXIFTag',
            Writable =&gt; 'int16u',
            WriteGroup =&gt; 'IFD0',
        },
        <span class=com># add more user-defined EXIF tags here...</span>
    },
    <span class=com># the <a href="geotag.html">Geotag feature</a> writes GPSPitch and GPSRoll tags, but these
    # aren't standard EXIF so we define custom tags here:</span>
    'Image::ExifTool::GPS::Main' =&gt; {
        <span class=com># Example 2.  GPS:GPSPitch</span>
        0xd000 =&gt; {
            Name =&gt; 'GPSPitch',
            Writable =&gt; 'rational64s',
        },
        <span class=com># Example 3.  GPS:GPSRoll</span>
        0xd001 =&gt; {
            Name =&gt; 'GPSRoll',
            Writable =&gt; 'rational64s',
        },
    },
    <span class=com># IPTC tags are added to a specific record type (eg. application record):
    # (Note: IPTC tag ID's are limited to the range 0-255)</span>
    'Image::ExifTool::IPTC::ApplicationRecord' =&gt; {
        <span class=com># Example 4.  IPTC:NewIPTCTag</span>
        160 =&gt; {
            Name =&gt; 'NewIPTCTag',
            Format =&gt; 'string[0,16]',
        },
        <span class=com># add more user-defined IPTC ApplicationRecord tags here...</span>
    },
    <span class=com># XMP tags may be added to existing namespaces:</span>
    'Image::ExifTool::XMP::xmp' =&gt; {
        <span class=com># Example 5.  XMP-xmp:NewXMPxmpTag</span>
        NewXMPxmpTag =&gt; { Groups =&gt; { 2 =&gt; 'Author' } },
        <span class=com># add more user-defined XMP-xmp tags here...</span>
    },
    <span class=com># special Geotag tags for XMP-exif:</span>
    'Image::ExifTool::XMP::exif' =&gt; {
        <span class=com># Example 6.  XMP-exif:GPSPitch</span>
        GPSPitch =&gt; { Writable =&gt; 'rational', Groups =&gt; { 2 =&gt; 'Location' } },
        <span class=com># Example 7.  XMP-exif:GPSRoll</span>
        GPSRoll  =&gt; { Writable =&gt; 'rational', Groups =&gt; { 2 =&gt; 'Location' } },
    },
    <span class=com># new XMP namespaces (eg. xxx) must be added to the Main XMP table:</span>
    'Image::ExifTool::XMP::Main' =&gt; {
        <span class=com># namespace definition for examples 8 to 11</span>
        xxx =&gt; { <span class=com># &lt;-- must be the same as the NAMESPACE prefix</span>
            SubDirectory =&gt; {
                TagTable =&gt; 'Image::ExifTool::UserDefined::xxx',
                <span class=com># (see the definition of this table below)</span>
            },
        },
        <span class=com># add more user-defined XMP namespaces here...</span>
    },
    <span class=com># new PNG tags are added to the PNG::TextualData table:</span>
    'Image::ExifTool::PNG::TextualData' =&gt; {
        <span class=com># Example 12.  PNG:NewPngTag1</span>
        NewPngTag1 =&gt; { },
        <span class=com># Example 13.  PNG:NewPngTag2</span>
        NewPngTag2 =&gt; { iTXt =&gt; 1 }, <span class=com># (force this tag to be written as iTXt)</span>
        <span class=com># Example 14.  PNG:NewPngTag3</span>
        NewPngTag3 =&gt; { },
    },
    <span class=com># add a new MIE tag (NewMieTag1) and group (MIE-Test) to MIE-Meta
    # (Note: MIE group names must NOT end with a number)</span>
    'Image::ExifTool::MIE::Meta' =&gt; {
        <span class=com># Example 15.  MIE-Meta:NewMieTag1</span>
        NewMieTag1 =&gt; {
            Writable =&gt; 'rational64u',
            Units =&gt; [ 'cm', 'in' ],
        },
        <span class=com># new MIE "Test" group for example 16</span>
        Test =&gt; {
            SubDirectory =&gt; {
                TagTable =&gt; 'Image::ExifTool::UserDefined::MIETest',
                DirName =&gt; 'MIE-Test',
            },
        },
    },
    <span class=com># Composite tags are added to the Composite table:</span>
    'Image::ExifTool::Composite' =&gt; {
        <span class=com># Composite tags have values that are derived from the values of
        # other tags.  The Require/Desire elements below specify constituent
        # tags that must/may exist, and the keys of these hashes are used as
        # indices in the @val array of the ValueConv expression to access the
        # numerical (-n) values of these tags.  Print-converted values are
        # accessed via the @prt array.  All Require'd tags must exist for
        # the Composite tag to be evaluated.  If no Require'd tags are
        # specified, then at least one of the Desire'd tags must exist.  See
        # the Composite table in Image::ExifTool::Exif for more examples,
        # and lib/Image/ExifTool/README for all of the details.
        # The first few examples demonstrate simplifications which may be
        # used if only one tag is Require'd or Desire'd:
        # 1) the Require lookup may be replaced with a simple tag name
        # 2) "$val" may be used to represent "$val[0]" in the expression</span>
        FileExtension =&gt; {
            Require =&gt; 'FileName',
            ValueConv =&gt; '$val=~/\.([^.]*)$/; $1',
        },
        <span class=com># override CircleOfConfusion tag to use D/1750 instead of D/1440</span>
        CircleOfConfusion =&gt; {
            Require =&gt; 'ScaleFactor35efl',
            Groups =&gt; { 2 =&gt; 'Camera' },
            ValueConv =&gt; 'sqrt(24*24+36*36) / ($val * 1750)',
            <span class=com># an optional PrintConv may be used to format the value</span>
            PrintConv =&gt; 'sprintf("%.3f mm",$val)',
        },
        <span class=com># generate a description for this file type</span>
        FileTypeDescription =&gt; {
            Require =&gt; 'FileType',
            ValueConv =&gt; 'GetFileType($val,1) || $val',
        },
        <span class=com># calculate physical image size based on resolution</span>
        PhysicalImageSize =&gt; {
            Require =&gt; {
                0 =&gt; 'ImageWidth',
                1 =&gt; 'ImageHeight',
                2 =&gt; 'XResolution',
                3 =&gt; 'YResolution',
                4 =&gt; 'ResolutionUnit',
            },
            ValueConv =&gt; '$val[0]/$val[2] . " " . $val[1]/$val[3]',
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