Provided by: libimage-exiftool-perl_13.10+dfsg-1_all bug

NAME

       Image::ExifTool - Read and write meta information

SYNOPSIS

         use Image::ExifTool qw(:Public);

         # ---- Simple procedural usage ----

         # Get hash of meta information tag names/values from an image
         $info = ImageInfo('a.jpg');

         # ---- Object-oriented usage ----

         # Create a new Image::ExifTool object
         $exifTool = Image::ExifTool->new;

         # Extract meta information from an image
         $exifTool->ExtractInfo($file, \%options);

         # Get list of tags in the order they were found in the file
         @tagList = $exifTool->GetFoundTags('File');

         # Get the value of a specified tag
         $value = $exifTool->GetValue($tag, $type);

         # Get a tag description
         $description = $exifTool->GetDescription($tag);

         # Get the group name associated with this tag
         $group = $exifTool->GetGroup($tag, $family);

         # Set a new value for a tag
         $exifTool->SetNewValue($tag, $newValue);

         # Write new meta information to a file
         $success = $exifTool->WriteInfo($srcfile, $dstfile);

         # ...plus a host of other useful methods...

DESCRIPTION

       Reads and writes meta information in a wide variety of files, including the maker notes of many digital
       cameras by various manufacturers such as Canon, Casio, DJI, FLIR, FujiFilm, GE, GoPro, HP, JVC/Victor,
       Kodak, Leaf, Minolta/Konica-Minolta, Nikon, Nintendo, Olympus/Epson, Panasonic/Leica, Pentax/Asahi, Phase
       One, Reconyx, Ricoh, Samsung, Sanyo, Sigma/Foveon and Sony.

       Below is a list of file types and meta information formats currently supported by ExifTool (r = read, w =
       write, c = create):

         File Types
         ------------+-------------+-------------+-------------+------------
         360   r/w   | DOCX  r     | ITC   r     | NUMBERS r   | RAW   r/w
         3FR   r     | DPX   r     | J2C   r     | NXD   r     | RIFF  r
         3G2   r/w   | DR4   r/w/c | JNG   r/w   | O     r     | RSRC  r
         3GP   r/w   | DSS   r     | JP2   r/w   | ODP   r     | RTF   r
         7Z    r     | DV    r     | JPEG  r/w   | ODS   r     | RW2   r/w
         A     r     | DVB   r/w   | JSON  r     | ODT   r     | RWL   r/w
         AA    r     | DVR-MS r    | JXL   r/w   | OFR   r     | RWZ   r
         AAC   r     | DYLIB r     | K25   r     | OGG   r     | RM    r
         AAE   r     | EIP   r     | KDC   r     | OGV   r     | SEQ   r
         AAX   r/w   | EPS   r/w   | KEY   r     | ONP   r     | SKETCH r
         ACR   r     | EPUB  r     | LA    r     | OPUS  r     | SO    r
         AFM   r     | ERF   r/w   | LFP   r     | ORF   r/w   | SR2   r/w
         AI    r/w   | EXE   r     | LIF   r     | ORI   r/w   | SRF   r
         AIFF  r     | EXIF  r/w/c | LNK   r     | OTF   r     | SRW   r/w
         APE   r     | EXR   r     | LRV   r/w   | PAC   r     | SVG   r
         ARQ   r/w   | EXV   r/w/c | M2TS  r     | PAGES r     | SWF   r
         ARW   r/w   | F4A/V r/w   | M4A/V r/w   | PBM   r/w   | THM   r/w
         ASF   r     | FFF   r/w   | MACOS r     | PCD   r     | TIFF  r/w
         AVI   r     | FITS  r     | MAX   r     | PCX   r     | TORRENT r
         AVIF  r/w   | FLA   r     | MEF   r/w   | PDB   r     | TTC   r
         AZW   r     | FLAC  r     | MIE   r/w/c | PDF   r/w   | TTF   r
         BMP   r     | FLIF  r/w   | MIFF  r     | PEF   r/w   | TXT   r
         BPG   r     | FLV   r     | MKA   r     | PFA   r     | VCF   r
         BTF   r     | FPF   r     | MKS   r     | PFB   r     | VNT   r
         C2PA  r     | FPX   r     | MKV   r     | PFM   r     | VRD   r/w/c
         CHM   r     | GIF   r/w   | MNG   r/w   | PGF   r     | VSD   r
         COS   r     | GLV   r/w   | MOBI  r     | PGM   r/w   | WAV   r
         CR2   r/w   | GPR   r/w   | MODD  r     | PLIST r     | WDP   r/w
         CR3   r/w   | GZ    r     | MOI   r     | PICT  r     | WEBP  r/w
         CRM   r/w   | HDP   r/w   | MOS   r/w   | PMP   r     | WEBM  r
         CRW   r/w   | HDR   r     | MOV   r/w   | PNG   r/w   | WMA   r
         CS1   r/w   | HEIC  r/w   | MP3   r     | PPM   r/w   | WMV   r
         CSV   r     | HEIF  r/w   | MP4   r/w   | PPT   r     | WPG   r
         CUR   r     | HTML  r     | MPC   r     | PPTX  r     | WTV   r
         CZI   r     | ICC   r/w/c | MPG   r     | PS    r/w   | WV    r
         DCM   r     | ICO   r     | MPO   r/w   | PSB   r/w   | X3F   r/w
         DCP   r/w   | ICS   r     | MQV   r/w   | PSD   r/w   | XCF   r
         DCR   r     | IDML  r     | MRC   r     | PSP   r     | XISF  r
         DFONT r     | IIQ   r/w   | MRW   r/w   | QTIF  r/w   | XLS   r
         DIVX  r     | IND   r/w   | MXF   r     | R3D   r     | XLSX  r
         DJVU  r     | INSP  r/w   | NEF   r/w   | RA    r     | XMP   r/w/c
         DLL   r     | INSV  r     | NKA   r     | RAF   r/w   | ZIP   r
         DNG   r/w   | INX   r     | NKSC  r/w   | RAM   r     |
         DOC   r     | ISO   r     | NRW   r/w   | RAR   r     |

         Meta Information
         ----------------------+----------------------+---------------------
         EXIF           r/w/c  |  CIFF           r/w  |  Ricoh RMETA    r
         GPS            r/w/c  |  AFCP           r/w  |  Picture Info   r
         IPTC           r/w/c  |  Kodak Meta     r/w  |  Adobe APP14    r
         XMP            r/w/c  |  FotoStation    r/w  |  MPF            r
         MakerNotes     r/w/c  |  PhotoMechanic  r/w  |  Stim           r
         Photoshop IRB  r/w/c  |  JPEG 2000      r    |  DPX            r
         ICC Profile    r/w/c  |  DICOM          r    |  APE            r
         MIE            r/w/c  |  Flash          r    |  Vorbis         r
         JFIF           r/w/c  |  FlashPix       r    |  SPIFF          r
         Ducky APP12    r/w/c  |  QuickTime      r    |  DjVu           r
         PDF            r/w/c  |  Matroska       r    |  M2TS           r
         PNG            r/w/c  |  MXF            r    |  PE/COFF        r
         Canon VRD      r/w/c  |  PrintIM        r    |  AVCHD          r
         Nikon Capture  r/w/c  |  FLAC           r    |  ZIP            r
         GeoTIFF        r/w/c  |  ID3            r    |  (and more)

CONFIGURATION

       User-defined tags can be added via the ExifTool configuration file, or by defining the
       %Image::ExifTool::UserDefined hash before calling any ExifTool methods.  See "ExifTool_config" in the
       ExifTool distribution for more details.

       By default ExifTool looks for a configuration file named ".ExifTool_config" first in your home directory,
       then in the directory of the application script, but a different directory may be specified by setting
       the EXIFTOOL_HOME environment variable, or a different file may be specified by setting the ExifTool
       "configFile" variable before using Image::ExifTool.  For example:

           BEGIN { $Image::ExifTool::configFile = '/Users/phil/myconfig.cfg' }
           use Image::ExifTool;

       The configuration feature may also be disabled by setting "configFile" to an empty string:

           BEGIN { $Image::ExifTool::configFile = '' }
           use Image::ExifTool;

EXPORTS

       Exports nothing by default, but "ImageInfo" and all static methods may be exported with the ":Public"
       export list.

METHODS

       All ExifTool features are accessed through the methods of the public interface listed below.  Other
       Image::ExifTool methods and modules should not be accessed directly because their interface may change
       with future versions.

       None of these methods should ever die or issue warnings to STDERR if called with the proper arguments
       (with the exception of "SetNewValue" which may send an error message to STDERR, but only when called in
       scalar context).  Error and warning messages that occur during processing are stored in the values of the
       Error and Warning tags, and are accessible via the "GetValue" method to retrieve a single Error or
       Warning message, or "GetInfo" to retrieve any number of them.

       The ExifTool methods are not thread safe.

   new
       Creates a new ExifTool object.

           $exifTool = Image::ExifTool->new;

       One ExifTool object may be used to process many files, so creating multiple ExifTool objects usually is
       not necessary.

       Note that ExifTool uses AUTOLOAD to load non-member methods, so any class using Image::ExifTool as a base
       class must define an AUTOLOAD which calls Image::ExifTool::DoAutoLoad().  eg)

           sub AUTOLOAD
           {
               Image::ExifTool::DoAutoLoad($AUTOLOAD, @_);
           }

   ImageInfo
       Read image file and return meta information.  This is the one step function for retrieving meta
       information from an image.  Internally, "ImageInfo" calls "ExtractInfo" to extract the information,
       "GetInfo" to generate the information hash, and "GetTagList" for the returned tag list.

           # return meta information for 2 tags only (procedural)
           $info = ImageInfo($filename, $tag1, $tag2);

           # return information about an open image file (object-oriented)
           $info = $exifTool->ImageInfo(\*FILE);

           # return information from image data in memory for specified tags
           %options = (PrintConv => 0);
           @tagList = qw(filename imagesize xmp:creator exif:* -ifd1:*);
           $info = ImageInfo(\$imageData, \@tagList, \%options);

           # extract information from an embedded thumbnail image
           $info = ImageInfo('image.jpg', 'thumbnailimage');
           $thumbInfo = ImageInfo($$info{ThumbnailImage});

       Inputs:
           "ImageInfo"  is very flexible about the input arguments, and interprets them based on their type.  It
           may be called with one or more arguments.  The one required argument is either a  SCALAR  (the  image
           file  name),  a  file reference (a reference to the image file) or a SCALAR reference (a reference to
           the image in memory).  Other arguments are optional.  The order of the arguments is not  significant,
           except that the first SCALAR is taken to be the file name unless a file reference or scalar reference
           comes earlier in the argument list.

           Below is an explanation of how the "ImageInfo" function arguments are interpreted:

           ExifTool ref
               "ImageInfo"  may  be  called with an ExifTool object if desired.  Advantages of using the object-
               oriented form are that options may be set before calling "ImageInfo", and the object may be  used
               afterward to access member functions.  Must be the first argument if used.

           SCALAR
               The  first  scalar argument is taken to be the file name unless an earlier argument specified the
               image data via a file reference (file ref) or data reference (SCALAR ref).  The remaining  scalar
               arguments  are  names  of  tags  for requested information.  All tags are returned if no tags are
               specified.

               Tag names are case-insensitive and may be prefixed by optional group names separated  by  colons.
               A  group  name  may  begin with a family number (eg.  '1IPTC:Keywords'), to restrict matches to a
               specific family.  In the tag name, a '?' matches any single character and a '*' matches  zero  or
               more  characters.   Thus 'GROUP:*' represents all tags in a specific group.  Wildcards may not be
               used in group names, with the exception that a group name of '*'  may  be  used  to  extract  all
               available  instances  of  a  tag  regardless  of the "Duplicates" setting (eg. '*:WhiteBalance').
               Multiple groups may be specified (eg. 'EXIF:Time:*' extracts all EXIF Time tags). And finally,  a
               leading  '-'  indicates  a  tag  to  be  excluded  (eg.  '-IFD1:*'), or a trailing '#' causes the
               ValueConv value to be returned for this tag.

               Note that keys in the returned information hash and elements of the returned  tag  list  are  not
               necessarily the same as these tag names because group names are removed, the case may be changed,
               and  an  instance  number may be added.  For this reason it is best to use either the keys of the
               returned hash or the elements of the returned tag list when accessing the tag values.

               See Image::ExifTool::TagNames for a complete list of ExifTool tag names.

           File ref
               A reference to an open image file.  If you use this method (or  a  SCALAR  reference)  to  access
               information  in  an image, the FileName and Directory tags will not be returned.  (Also, a number
               of the File System tags will not be returned unless it is a plain file.)  Image processing begins
               at the current file position, and on return the file position is unspecified.  May  be  either  a
               standard  filehandle,  or a reference to a File::RandomAccess object.  Note that the file remains
               open and must be closed by the caller after "ImageInfo" returns.

               [Advanced:  To allow a  non-rewindable  stream  (eg.  a  network  socket)  to  be  re-read  after
               processing with ExifTool, first wrap the file reference in a File::RandomAccess object, then pass
               this object to "ImageInfo".  The File::RandomAccess object will buffer the file if necessary, and
               may be used to re-read the file after "ImageInfo" returns.]

           SCALAR ref
               A reference to image data in memory.

           ARRAY ref
               Reference  to  a  list of tag names.  On entry, any elements in the list are added to the list of
               requested tags.  Tags with names beginning with '-'  are  excluded.   On  return,  this  list  is
               updated to contain an ordered list of tag keys for the returned information.

               There will be 1:1 correspondence between the requested tags and the returned tag keys only if the
               "Duplicates"  option  is  0 and "Sort" is 'Input'.  (With "Duplicates" enabled, there may be more
               entries in the returned list of tag keys, and with other "Sort" settings the entries may  not  be
               in the same order as requested.)  If a requested tag doesn't exist, a tag key is still generated,
               but the tag value is undefined.

               Note:  Do not reuse this list in subsequent calls to "ImageInfo" because it returns tag keys, not
               names, and the list will grow for each call resulting in increasingly slower performance.

           HASH ref
               Reference to a hash containing the options settings valid for  this  call  only.   See  "Options"
               documentation  below  for  a  list  of  available  options.   Options  specified  as arguments to
               "ImageInfo" take precedence over "Options" settings.

       Return Values:
           "ImageInfo" returns a reference to a hash of tag-key/value pairs.  The tag keys  are  identifiers  --
           essentially  case-sensitive tag names with an appended instance number if multiple tags with the same
           name were extracted from the image.  Many of the ExifTool functions require a tag key as an argument.
           Use "GetTagName [static]" to get the tag name for a given tag key.  Note that the  case  of  the  tag
           names  may  not  be  the  same  as  requested.  Here is a simple example to print out the information
           returned by "ImageInfo":

               foreach (sort keys %$info) {
                   print "$_ => $$info{$_}\n";
               }

           Values of the returned hash are usually simple scalars, but a scalar reference is  used  to  indicate
           binary  data  and  an  array reference may be used to indicate a list.  Also, a hash reference may be
           returned if the "Struct" option is used (see the "OrderedKeys"  option  to  obtain  the  hash  keys).
           Lists of values are joined by commas into a single string only if the PrintConv option is enabled and
           the ListJoin option is enabled (which are the defaults).  Note that binary values are not necessarily
           extracted  unless  specifically  requested,  or  the  Binary  option  is  enabled  and the tag is not
           specifically excluded.  If not extracted the value is a reference to a string  of  the  form  "Binary
           data ##### bytes".

           The code below gives an example of how to handle these return values, as well as illustrating the use
           of other ExifTool functions:

               use Image::ExifTool;
               my $exifTool = Image::ExifTool->new;
               $exifTool->Options(Unknown => 1);
               my $info = $exifTool->ImageInfo('a.jpg');
               my $group = '';
               my $tag;
               foreach $tag ($exifTool->GetFoundTags('Group0')) {
                   if ($group ne $exifTool->GetGroup($tag)) {
                       $group = $exifTool->GetGroup($tag);
                       print "---- $group ----\n";
                   }
                   my $val = $info->{$tag};
                   if (ref $val eq 'SCALAR') {
                       if ($$val =~ /^Binary data/) {
                           $val = "($$val)";
                       } else {
                           my $len = length($$val);
                           $val = "(Binary data $len bytes)";
                       }
                   }
                   printf("%-32s : %s\n", $exifTool->GetDescription($tag), $val);
               }

       Notes:
           ExifTool  returns  all  values  as  byte strings of encoded characters.  Perl wide characters are not
           used.  See "CHARACTER ENCODINGS" for details about the encodings.  By default, most  returned  values
           are  encoded  in  UTF-8.   For  these,  Encode::decode_utf8() may be used to convert to a sequence of
           logical Perl characters.

           As well as tags representing information extracted from the image, the following Extra tags generated
           by ExifTool may be returned:

               ExifToolVersion - The ExifTool version number.

               Error - An error message if the image could not be processed.

               Warning - A warning message if problems were encountered while
                         processing the image.

   Options
       Get/set ExifTool options.  This function can be called to set the default options for an ExifTool object.
       Options set this way are in effect for all function calls but may be  overridden  by  options  passed  as
       arguments to some functions.  Option names are not case sensitive, but option values are.

       The  default option values may be changed by defining a %Image::ExifTool::UserDefined::Options hash.  See
       the ExifTool_config file in the full ExifTool distribution  for  examples.   Unless  otherwise  noted,  a
       default of undef has the same effect as a value of 0 for options with numerical values.

           # exclude the 'OwnerName' tag from returned information
           $exifTool->Options(Exclude => 'OwnerName');

           # only get information in EXIF or MakerNotes groups
           $exifTool->Options(Group0 => ['EXIF', 'MakerNotes']);

           # ignore information from IFD1
           $exifTool->Options(Group1 => '-IFD1');

           # sort by groups in family 2, and extract unknown tags
           $exifTool->Options(Sort => 'Group2', Unknown => 1);

           # reset DateFormat option
           $exifTool->Options(DateFormat => undef);

           # do not extract duplicate tag names
           $oldSetting = $exifTool->Options(Duplicates => 0);

           # get current Verbose setting
           $isVerbose = $exifTool->Options('Verbose');

           # set a user parameter
           $exifTool->Options(UserParam => 'MyParam=some value');

       Inputs:
           0) ExifTool object reference

           1) Option parameter name (case-insensitive)

           2) [optional] Option parameter value (may be undef to clear option)

           3-N) [optional] Additional parameter/value pairs

       Option Parameters:
           Note  that  these  API options may also be used in the exiftool application via the command-line -api
           option.

           Binary
               Flag to extract the value data for all binary tags.  Tag values representing  large  binary  data
               blocks (eg. ThumbnailImage) are not necessarily extracted unless this option is set or the tag is
               specifically requested by name.  Default is undef.

           BlockExtract
               Flag  to  extract some directories (mentioned in the ExifTool tag name documentation) as a block.
               Setting this to a value of 2 also prevents parsing the block to extract tags contained within.

           ByteOrder
               The byte order for newly created EXIF segments when  writing.   Note  that  if  EXIF  information
               already  exists,  the  existing  order is maintained.  Valid values are 'MM', 'II' and undef.  If
               ByteOrder is not defined (the default), then the maker note byte order is used (if they are being
               copied),  otherwise  big-endian  ('MM')  order  is  assumed.   This  can  also  be  set  via  the
               ExifByteOrder tag, but the ByteOrder option takes precedence if both are set.

           ByteUnit
               Units  for  print  conversion  of  FileSize  and other byte values.  Either 'SI' (eg. kB for 1000
               bytes) or 'Binary' (eg. KiB for 1024 bytes).  Default is 'SI'.

           Charset
               Character set for encoding character tag values passed to/from ExifTool with  code  points  above
               U+007F.  Default is 'UTF8'.  Valid values are listed below, case is not significant:

                 Value        Alias(es)        Description
                 -----------  ---------------  ----------------------------------
                 UTF8         cp65001, UTF-8   UTF-8 characters
                 Latin        cp1252, Latin1   Windows Latin1 (West European)
                 Latin2       cp1250           Windows Latin2 (Central European)
                 Cyrillic     cp1251, Russian  Windows Cyrillic
                 Greek        cp1253           Windows Greek
                 Turkish      cp1254           Windows Turkish
                 Hebrew       cp1255           Windows Hebrew
                 Arabic       cp1256           Windows Arabic
                 Baltic       cp1257           Windows Baltic
                 Vietnam      cp1258           Windows Vietnamese
                 Thai         cp874            Windows Thai
                 DOSLatinUS   cp437            DOS Latin US
                 DOSLatin1    cp850            DOS Latin1
                 DOSCyrillic  cp866            DOS Cyrillic
                 MacRoman     cp10000, Roman   Macintosh Roman
                 MacLatin2    cp10029          Macintosh Latin2 (Central Europe)
                 MacCyrillic  cp10007          Macintosh Cyrillic
                 MacGreek     cp10006          Macintosh Greek
                 MacTurkish   cp10081          Macintosh Turkish
                 MacRomanian  cp10010          Macintosh Romanian
                 MacIceland   cp10079          Macintosh Icelandic
                 MacCroatian  cp10082          Macintosh Croatian

               Note  that  this option affects some types of information when reading/writing the file and other
               types when getting/setting tag values, so it must be defined for both types of access.   See  the
               "CHARACTER ENCODINGS" section for more information about the handling of special characters.

           CharsetEXIF
               Internal encoding to use for stored EXIF "ASCII" string values.  May also be set to undef to pass
               through  EXIF  "ASCII"  values  without  recoding.   Set  to  "UTF8"  to  conform  with  the  MWG
               recommendation.  Default is undef.

           CharsetFileName
               External character set used for file names passed to ExifTool functions.  Default  is  undef  but
               "UTF8" is assumed in Windows if the file name contains special characters and is valid UTF8.  May
               also be set to an empty string to avoid "encoding must be specified" warnings on Windows.

           CharsetID3
               Internal  encoding  to  assume  for  ID3v1 strings.  By the specification ID3v1 strings should be
               encoded in ISO 8859-1 (essentially Latin), but some applications may use local encoding  instead.
               Default is 'Latin'.

           CharsetIPTC
               Fallback  internal IPTC character set to assume if IPTC information contains no CodedCharacterSet
               tag.  Possible values are the same as the "Charset" option.  Default is 'Latin'.

               Note that this option affects some types of information when reading/writing the file  and  other
               types when getting/setting tag values, so it must be defined for both types of access.

           CharsetPhotoshop
               Internal encoding to assume for Photoshop IRB resource names.  Default is 'Latin'.

           CharsetQuickTime
               Internal  encoding  to assume for QuickTime strings stored with an unspecified encoding.  Default
               is 'MacRoman'.

           CharsetRIFF
               Internal encoding to assume for strings in RIFF metadata (eg. AVI and WAV  files).   The  default
               value  of  0  assumes "Latin" encoding unless otherwise specified by the RIFF CSET chunk.  Set to
               undef to pass through strings without recoding.  Default is 0.

           Compact
               Comma-delimited list of settings for writing compact XMP.  Below is a list of available settings.
               Note that 'NoPadding' effects only embedded XMP since padding is never  written  for  stand-alone
               XMP  files.  Also note that 'OneDesc' is not recommended when writing XMP larger than 64 KiB to a
               JPG file because it interferes with ExifTool's technique of splitting off  large  rdf:Description
               elements  into  the extended XMP.  Case is not significant for any of these options.  Aliases are
               given in brackets. Default is undef.

                 NoPadding - Avoid 2 KiB of recommended padding at end of XMP (NoPad)
                 NoIndent  - No spaces to indent lines (NoSpace, NoSpaces)
                 NoNewline - Avoid unnecessary newlines (NoNewlines)
                 Shorthand - Use XMP Shorthand format
                 OneDesc   - Combine properties into a single rdf:Description (OneDescr)
                 AllSpace  - Equivalent to 'NoPadding,NoIndent,NoNewline'
                 AllFormat - Equivalent to 'Shorthand,OneDesc'
                 All       - Equivalent to 'AllSpace,AllFormat'

           Composite
               Flag to generate Composite tags when extracting information.  Default is 1.

           Compress
               Flag to write new values in compressed format if possible.  Has no  effect  unless  the  relevant
               compression  library  is available.  Valid when writing metadata to PNG, JXL, HEIC or MIE images.
               Setting this to zero causes JXL metadata to be rewritten as uncompressed when edited.  Default is
               undef.

           CoordFormat
               Format for printing GPS coordinates.  This is a printf format string with specifiers for degrees,
               minutes and seconds in that order, however minutes and seconds may be omitted.  If the hemisphere
               is known, a reference direction (N, S, E or W) is appended to each printed coordinate, but adding
               a "+" or "-" to the first format specifier (eg. "%+.6f" or "%-.6f") prints  a  signed  coordinate
               instead  ("+"  also  adds  a leading plus sign to positive coordinates, while "-" does not).  For
               example, the following table gives the output for the same coordinate using various formats:

                     CoordFormat        Example Output
                 -------------------  ------------------
                 q{%d deg %d' %.2f"}  54 deg 59' 22.80"  (default for reading)
                 q{%d %d %.8f}        54 59 22.80000000  (default for copying)
                 q{%d deg %.4f min}   54 deg 59.3800 min
                 q{%.6f degrees}      54.989667 degrees

               Note:  To avoid loss of precision, the default coordinate format is different when  copying  tags
               with "SetNewValuesFromFile".

           DateFormat
               Format   for   printing   date/time   values.    See   "strftime"   in   the  POSIX  package  and
               <https://exiftool.org/filename.html#codes> for details about the format string.  If the date  can
               not be converted, the value is left unchanged unless the StrictDate option is set.  ExifTool adds
               a      few      additional      format      specifiers      (%f,      %s     and     %z),     see
               <https://exiftool.org/filename.html#codes> for more details. The  inverse  conversion  (ie.  when
               calling  "SetNewValue")  is  performed  only if POSIX::strptime or Time::Piece is installed.  The
               default setting of undef causes date/time values to remain in standard EXIF format (similar to  a
               DateFormat of "%Y:%m:%d %H:%M:%S").

           Duplicates
               Flag  to return values from tags with duplicate names when extracting information.  Default is 1.
               Forced to 1 when copying tags with "SetNewValuesFromFile".

           Escape
               Escape special characters in extracted values for HTML  or  XML.   Also  unescapes  HTML  or  XML
               character  entities in input values passed to "SetNewValue".  Valid settings are 'HTML', 'XML' or
               undef.  Default is undef.

           Exclude
               Exclude specified tags when extracting information.  Note that this option is applied  after  all
               of the tags have already been loaded into memory (so different tags may be excluded in subsequent
               calls  to  "GetInfo").  See  the  IgnoreTags option to save memory by not loading the tags in the
               first place.  The option value is either a tag name or reference  to  a  list  of  tag  names  to
               exclude.   The  case  of  tag  names is not significant.  This option is ignored for specifically
               requested tags.  Tags may also be excluded by preceding their name with a '-' in the arguments to
               "ImageInfo".

           ExtendedXMP
               This setting affects the reading and editing of extended XMP in JPEG images.   According  to  the
               XMP  specification, extended XMP is only valid if it has the GUID specified by the HasExtendedXMP
               tag, so by default ExifTool will ignore other extended XMP, but this option allows  full  control
               over the extended XMP to be extracted.

                    0   - Ignore all extended XMP
                    1   - Read extended XMP with valid GUID only (default)
                    2   - Read extended XMP with any GUID
                 <guid> - Read extended XMP with a specific GUID

           ExtractEmbedded
               Flag  to  extract  information from embedded documents in EPS files, embedded EPS information and
               JPEG and Jpeg2000 images in PDF files, embedded MPF images in JPEG and MPO files, metadata  after
               the  first  Cluster  in MKV files, timed metadata in videos, all frames of a multipart EXR image,
               and the resource fork of Mac OS files. A setting of 2 also causes the H264 video  stream  in  MP4
               files  to  be parsed until the first SEI message is decoded, or 3 to parse the entire H264 stream
               in MP4 videos and the entire M2TS file to look for any unlisted program containing GPS  metadata.
               Default is undef.

           FastScan
               Flag to increase speed when reading files by avoiding extraction of some types of metadata.  With
               this  option  set  to  1, ExifTool will not scan to the end of a JPEG image to check for an AFCP,
               CanonVRD, FotoStation, PhotoMechanic, MIE or PreviewImage trailer.  This also stops  the  parsing
               after  the  first  comment  in GIF images, and at the audio/video data of RIFF-format files (AVI,
               WAV, etc), so any trailing metadata (eg. XMP written by some  utilities)  may  be  missed.   Also
               disables  input buffering for some types of files to reduce memory usage when reading from a non-
               seekable stream, and bypasses CRC validation for speed when writing  PNG  files.   When  combined
               with  the ScanForXMP option, prevents scanning for XMP in recognized file types.  With a value of
               2, ExifTool will also avoid extracting any EXIF MakerNote information, and will  stop  processing
               at  the  IDAT  chunk  of  PNG  images  and  the mdat atom in QuickTime-format files.  (By the PNG
               specification, metadata is allowed after IDAT, but ExifTool always writes it before because  some
               utilities  will  ignore  it  otherwise.)   When  set  to 3 or higher, only pseudo system tags and
               FileType are generated. For 3, the file header is read to provide an educated guess at  FileType.
               For 4, the file is not read at all and FileType is determined based on the file's extension.  For
               5,  generation  of  Composite  tags is also disabled (like setting "Composite" to 0).  Default is
               undef.

           Filter
               Perl expression used to filter values for all tags.  The expression acts on the value of the Perl
               default variable ($_), and changes the value of this variable as required.  The current  ExifTool
               object  may  be  accessed  through  $self.  The value is not changed if $_ is set to undef.  List
               items are filtered individually.  Applies to all  returned  values  unless  PrintConv  option  is
               disabled.

           FilterW
               Perl  expression  used to filter PrintConv values when writing.  The expression acts on the value
               of the Perl default variable ($_), and changes the value  of  this  variable  as  required.   The
               current  ExifTool  object  may be accessed through $self.  The tag is not written if $_ is set to
               undef.

           FixBase
               Fix maker notes base offset.  A common problem with image editing software is that offsets in the
               maker notes are not adjusted properly when the file is modified.  This may cause the wrong values
               to be extracted for some maker note entries when reading the edited file.  FixBase  specifies  an
               integer value to be added to the maker notes base offset.  It may also be set to the empty string
               ('')  for  ExifTool  will  take its best guess at the correct base, or undef (the default) for no
               base adjustment.

           GeoDir
               [Not a real option] Provided as a convenience to allow  $Image::ExifTool::geoDir  to  be  set  at
               runtime.   This  variable specifies the directory for the Geolocation databases, and is used only
               once when these databases are loaded.

           Geolocation
               Flag   to   generate   geolocation   tags    based    on    the    GPSLatitude/GPSLongitude    or
               City/State/Province/Country read from a file.  This feature uses an included database with cities
               over  a  population  of 2000 from geonames.org. May be set to a string of the form "Lat,Lon" (eg.
               "44.56,-72.33")  or  city  with  optional  state/province,  country  and/or  country  code   (eg.
               "Paris,France")  to  act as a default for files not containing GPS or geolocation information, or
               include tag names with leading dollar signs separated by commas to specify the tags  to  use  for
               the  geolocation  input.   When  "Lat,Lon"  is  specified,  "num=##"  may  be added to return the
               specified number of nearby cities (the "Duplicates" option must also be used  for  the  duplicate
               tags  to be returned).  May include regular expressions for more flexible matching of city names.
               See <https://exiftool.org/geolocation.html> for more details.  Default is undef.

           GeolocAltNames
               Flag   to    search    alternate    Geolocation    city    names    if    available    (ie.    if
               $Image::ExifTool::Geolocation::altDir  has  been  set).  Set to 0 to disable use of the alternate
               names.  Default is 1.

           GeolocFeature
               Comma-separated list of feature codes to include in city search, or exclude if  the  list  begins
               with  a  dash  (-).   Valid feature codes are PPL, PPLA, PPLA2, PPLA3, PPLA4, PPLA5, PPLC, PPLCH,
               PPLF, PPLG, PPLH, PPLL, PPLQ, PPLR, PPLS, PPLW, PPLX, STLMT and Other, plus possible user-include
               codes if an alternate database is used.  See <http://www.geonames.org/export/codes.html#P> for  a
               description of these codes.  Default is undef.

           GeolocMaxDist
               Maximum  distance  in  km to the geolocation city.  The Geolocation tags are not generated if the
               distance is greater than this.  Default is undef.

           GeolocMinPop
               Minimum population for the Geolocation city.  Cities smaller than this are ignored.   Default  is
               undef.

           GeoMaxIntSecs
               Maximum  interpolation time in seconds for geotagging.  Geotagging is treated as an extrapolation
               if the Geotime value lies between two fixes in the same track which are separated by a number  of
               seconds  greater  than this.  Otherwise, the coordinates are calculated as a linear interpolation
               between the nearest fixes on either side of the Geotime value.  Set to 0 to disable interpolation
               and use the coordinates of  the  nearest  fix  instead  (provided  it  is  within  GeoMaxExtSecs,
               otherwise geotagging fails).  Default is 1800.

           GeoMaxExtSecs
               Maximum extrapolation time in seconds for geotagging.  Geotagging fails if the Geotime value lies
               outside  a  GPS  track by a number of seconds greater than this.  Otherwise, for an extrapolation
               the coordinates of the nearest fix are taken (ie. it is assumed that you  weren't  moving  during
               this period).  Default is 1800.

           GeoMaxHDOP
               Maximum  Horizontal (2D) Dilution Of Precision for geotagging.  GPS fixes are ignored if the HDOP
               is greater than this.  Default is undef.

           GeoMaxPDOP
               Maximum Position (3D) Dilution Of Precision for geotagging.  GPS fixes are ignored if the PDOP is
               greater than this.  Default is undef.

           GeoMinSats
               Minimum number of satellites for geotagging.  GPS fixes are ignored if  the  number  of  acquired
               satellites is less than this.  Default is undef.

           GeoSpeedRef
               Reference units for writing GPSSpeed when geotagging:

                   'K', 'k' or 'km/h'  - km/h
                   'M', 'm' or 'mph'   - mph
                   <anything else>     - knots (default undef)

           GlobalTimeShift
               Time  shift  to  apply  to  all  extracted date/time PrintConv values.  Does not affect ValueConv
               values.  Value is a date/time shift string (see Image::ExifTool::Shift(3pm)) with a  leading  '-'
               for negative shifts, or a tag name with option group prefix followed by '+' or '-' then the shift
               string.  Default is undef.

               Note:  When  specifying  a  number of months and/or years to shift, the tag for the starting date
               should be specified so the number of days can be determined unambiguously.  For example:

                   'createdate-1:0:0 0:0:0' - shift back by the length of the
                                              year before the CreateDate value
                   'xmp:createdate+0:2:0 0' - shift forward by the length of
                                              the 2 months after XMP:CreateDate

               If the starting tag is not specified, or the specified tag isn't available,  then  the  shift  is
               calculated based on the first shifted tag.

           Group#
               Extract  tags  only for specified groups in family # (Group0 assumed if # not given).  The option
               value may be a single group name or a reference to a list of  groups.   Case  is  significant  in
               group  names.  Specify a group to be excluded by preceding group name with a '-'.  See "GetGroup"
               for a description of group families, and "GetAllGroups [static]" for lists of group names.

           HexTagIDs
               Return hexadecimal instead of decimal for the family 7 group names of tags with numerical ID's.

           HtmlDump
               Dump information in hex to dynamic HTML web page.  The value may be 0-3 for  increasingly  larger
               limits  on  the  maximum  block  size.   Default  is 0.  Output goes to the file specified by the
               TextOut option (\*STDOUT by default).

           HtmlDumpBase
               Base for HTML dump offsets.  If not defined, the EXIF/TIFF base offset is used.   Set  to  0  for
               absolute offsets.  Default is undef.

           IgnoreGroups
               Comma-separated list of group names to ignore when reading.  The group names are case insensitive
               and  may  be preceeded by a family number.  Set to undef to clear the previous IgnoreGroups list.
               Default is undef.

           IgnoreMinorErrors
               Flag to ignore minor errors.  Causes minor  errors  to  be  downgraded  to  warnings,  and  minor
               warnings  to  be  ignored.   This  option is provided mainly to allow writing of files when minor
               errors occur, but by ignoring some minor warnings the behaviour of ExifTool  may  be  changed  to
               allow  some  questionable  operations to proceed (such as extracting thumbnail and preview images
               even if they don't have a recognizable  header).   Minor  errors  and  warnings  are  denoted  by
               "[minor]" at the start of the message, or "[Minor]" (with a capital "M") for warnings that affect
               processing when ignored.

           IgnoreTags
               Comma-separated  list  of  tag  names  to ignore when reading.  This may help in situations where
               memory is limited because the ignored tag values are not stored in memory. The tag names are case
               insensitive and group names and wildcards are not allowed.  A special tag name of  "All"  may  be
               used  to  ignore  all  tags  except those specified by the "RequestTags" option.  Set to undef to
               clear the previous IgnoreTags list.  Default is undef.

           ImageHashType
               Sets type of hash algorithem used for the ImageDataHash tag calculation.  Supported  options  are
               'MD5', 'SHA256', and 'SHA512'.  Default is 'MD5'.

           Lang
               Localized  language  for  exiftool  tag  descriptions, etc.  Available languages are given by the
               Image::ExifTool::Lang module  names  (eg.  'fr',  'zh_cn').   If  the  specified  language  isn't
               available,  the  option  is  not  changed.   May  be  set to undef to select the built-in default
               language.  Default is 'en'.

           LargeFileSupport
               Flag to indicate that 64-bit file offsets are supported on this system. If not set, processing is
               aborted if a chunk larger than 2 GB is encountered.  Set to 1 to process large chunks,  or  2  to
               process with a warning.  Default is 2.

           LimitLongValues
               When  extracting  values  for some specific tags (usually Unknown tags), the PrintConv values are
               length-limited and the value is truncated with an ellipsis ("[...]") if it  exceeds  a  specified
               length.   This option specifies the length limit for these tags.  A setting of 4 or less disables
               the limit (because the ellipsis string is longer than this).  Default is 60.

           ListItem
               Return only a specific item from list-type values.  A value of 0 returns the first  item  in  the
               list, 1 return the second item, etc.  Negative indices may also be used, with -1 representing the
               last  item in the list.  Applies only to the top-level list of nested lists.  Default is undef to
               return all items in the list.

           ListJoin
               Separator used to join the PrintConv value of multi-item List-type tags into a single string.  If
               not defined, multi-item lists are returned as  a  list  reference.   Does  not  affect  ValueConv
               values.  Default is ', '.

           ListSplit
               Regular  expression  used  to  split values of list-type tags into individual items when writing.
               (eg. use ',\\s*' to split a comma-separated  list.)   Split  when  writing  either  PrintConv  or
               ValueConv values.  Default is undef.

           MakerNotes
               Option to extract MakerNotes and other writable subdirectories (such as PrintIM) as a data block.
               Normally  when  the  MakerNotes  are  extracted  they  are  rebuilt  to  include data outside the
               boundaries of the original maker note data block,  but  a  value  of  2  disables  this  feature.
               Possible values are:

                 0 - Do not extract writable subdirectories (same as default of undef)
                 1 - Extract and rebuild maker notes into self-contained block
                 2 - Extract without rebuilding maker notes

           MDItemTags
               Flag  to  extract the OS X metadata item tags (see the "mdls" man page and "MacOS MDItem Tags" in
               Image::ExifTool::TagNames for more information).

           MissingTagValue
               Value for missing tags in tag name expressions (or tags where the advanced formatting  expression
               returns  undef).   If not set, a minor error is issued for missing values, or the value is set to
               '' if "IgnoreMinorErrors" is set.  Default is undef.

           NoDups
               Flag to remove duplicate items from queued values for List-type tags when writing.  This  applies
               only  to  queued  values,  and  doesn't  resolve duplicates with existing values in the file when
               adding to an existing list.  Default is undef.

           NoMandatory
               Flag to bypass writing of mandatory EXIF tags.  Default is undef.

           NoMultiExif
               Raise error when attempting to write multi-segment EXIF in a JPEG image.  Default is undef.

           NoPDFList
               Flag to avoid splitting PDF list-type tag values into separate items.  Default is undef.

           NoWarning[+]
               Regular expression to suppress matching warning messages.  For example,  a  value  of  "^Ignored"
               suppresses  all  warnings that begin with the word "Ignored".  Has no other effect on processing,
               unlike IgnoreMinorWarnings for some  warnings.   Start  the  expression  with  "(?i)"  for  case-
               insensitive matching.  Use NoWarning+ to add to existing expressions.  Default is undef.

           Password
               Password  for  reading/writing  password-protected  PDF  documents.  Ignored if a password is not
               required.  Character encoding of the password is determined by the value of the Charset option at
               processing time.  Default is undef.

           PrintConv
               Flag to enable automatic print conversion.  Also enables inverse print  conversion  for  writing.
               Default is 1.

           PrintCSV
               Flag  to  directly  print CSV-format output rather than extracting tags normally.  Currently this
               feature applies only to GM PDR data (see "GM Tags" in Image::ExifTool::TagNames).   Setting  this
               option automatically sets "IgnoreTags" to "all", and "ExtractEmbedded" to 1.  Default is undef.

           QuickTimeHandler
               Flag  set  to  add  an  'mdir' Handler to a newly created Meta box when adding QuickTime ItemList
               tags.  Adobe Bridge does not add this Handler, but it is commonly found  in  samples  from  other
               software,  and  it  has  been  reported  that  Apple QuickTime Player and Photos.apps will ignore
               ItemList tags if this is missing.  Default is 1.

           QuickTimePad
               Flag to preserve the padding of some QuickTime atoms when  writing.   QuickTime-based  Canon  CR3
               files pad the values of container atoms with null bytes.  This padding is removed by default when
               the  file  is  rewritten, but setting this option to 1 adds padding to preserve the original atom
               size if the new atom would be smaller than the original.  Default is undef.

           QuickTimeUTC
               Flag set to assume that QuickTime date/time values are stored as UTC, causing conversion to local
               time when they are extracted and from local  time  when  written.   According  to  the  QuickTime
               specification  date/time  values should be UTC, but many digital cameras store local time instead
               (presumably because they don't know the time zone), so the default is to not convert these  times
               (except  for  Canon  CR3  files,  which  always  use  UTC  times).  This option also disables the
               autodetection of incorrect time-zero offsets in QuickTime date/time values, and enforces  a  time
               zero of 1904 as per the QuickTime specification.

           RequestAll
               Flag  to  request all tags to be extracted.  This causes some tags to be generated which normally
               would not  be  unless  specifically  requested  (by  passing  the  tag  name  to  "ImageInfo"  or
               "ExtractInfo").   May  be set to 2 or 3 to enable generation of some additional tags as mentioned
               in the tag name documentation.  Default is undef.

           RequestTags
               List of additional tag and/or group names to request in the next  call  to  "ExtractInfo".   This
               option  is  useful  only  for  tags/groups  which aren't extracted unless specifically requested.
               Value may be a list reference, a delimited string of names (any delimiter is allowed),  or  undef
               to  clear  the  current  RequestTags list.  Groups are requested by adding a colon after the name
               (eg. "MacOS:").  Names are converted to lower case as they are added to  the  list.   Default  is
               undef.

           SaveBin
               Flag  to  save binary values of tags, accessible through calls to "GetValue" with a value type of
               "Bin".

           SaveFormat
               Flag to save EXIF/TIFF format type as the  family  6  group  name  when  extracting  information.
               Without  this  option  set,  the  family 6 group names are not generated.  Default is undef.  See
               "GetGroup" for more details.

           SavePath
               Flag to save the metadata path as the family 5 group name when extracting  information.   Without
               this  option  set,  the  family  5  group  names  are  not generated.  Default is undef.  See the
               "GetGroup" option for more details.

           ScanForXMP
               Flag to scan all files (even unrecognized formats) for XMP information  unless  XMP  was  already
               found  in  the  file.   When  combined with the FastScan option, only unrecognized file types are
               scanned for XMP.  Default is undef.

           Sort
               Specifies order to sort tags in returned list:

                 Input  - Sort in same order as input tag arguments (default)
                 File   - Sort in order that tags were found in the file
                 Tag    - Sort alphabetically by tag name
                 Descr  - Sort by tag description (for current Lang setting)
                 Group# - Sort by tag group, where # is zero or more family
                          numbers separated by colons. If # is not specified,
                          Group0 is assumed.  See GetGroup for a description
                          of group families.

           Sort2
               Secondary sort order used for tags within each group when Sort is 'Group':

                 File   - Sort in order tags were found in the file (default)
                 Tag    - Sort alphabetically by tag name
                 Descr  - Sort by tag description (for current Lang setting)

           StrictDate
               Flag to return undefined value for any date which can't be converted when the  DateFormat  option
               is used.  Default is undef.

                 undef - Same as 0 for reading/writing, or 1 for copying
                   0   - Return date/time value unchanged if it can't be converted
                   1   - Return undef if date/time value can't be converted

               When set to 1 while writing a PrintConv date/time value with the DateFormat option set, the value
               is  written  only if POSIX::strptime or Time::Piece is available and can successfully convert the
               value.

               For PNG CreationTime, a setting of 1 has the additional effect of causing  the  date/time  to  be
               reformatted  according  to  PNG  1.2  recommendation (RFC-1123) when writing, and a warning to be
               issued for any non-standard value when reading (but note  that  Windows  may  not  recognize  PNG
               date/time values in standard format).

           Struct
               Flag to return XMP structures as hash references instead of flattening into individual tags.  Has
               no effect when writing since both flattened and structured tags may always be written.  A special
               "_ordered_keys_"  element  containing  a list of ordered keys may exist if the structure elements
               are ordered (see the OrderedKeys method).  Possible values are:

                 undef - (default) Same as 0 for reading, 2 for copying
                   0   - Read/copy flattened tags
                   1   - Read/copy structured tags
                   2   - Read/copy both flattened and structured tags, but flag
                         flattened tags as 'unsafe' for copying

           StructFormat
               Format for serialized structures when reading/writing.

                 undef - Default ExifTool format
                 JSON  - JSON format
                 JSONQ - JSON with quoted numerical values

               Note that the JSONQ setting causes all values in the exiftool  application  -json  output  to  be
               quoted, regardless of whether or not they are in a structure.

           SystemTags
               Flag  to  extract  the  following additional File System tags:  FileAttributes, FileDeviceNumber,
               FileInodeNumber,  FileHardLinks,  FileUserID,  FileGroupID,   FileDeviceID,   FileBlockSize   and
               FileBlockCount.

           TextOut
               Output file reference for Verbose and HtmlDump options.  Default is \*STDOUT.

           TimeZone
               Set the time zone for local date/time values.  The value is a time zone offset like "+05:00" (but
               note  that  the  offset  is to UTC, not from UTC, so it is positive for western time zones), or a
               time zone name like "EST5EDT".  For Unix-based systems, the value may also be a time zone ID like
               "America/New_York".  Requires Time::Piece on Windows, or POSIX::tzset on other systems.   Default
               is undef.

           Unknown
               Flag  to  get  the values of unknown tags.  If set to 1, unknown tags are extracted from EXIF (or
               other tagged-format) directories.  If set to 2, unknown tags are also extracted from binary  data
               blocks.  Default is 0.

           UserParam
               Special  option to set/get user-defined parameters.  Useful to allow external input into tag name
               expressions and ValueConv logic.  Valid UserParam values are:

                 PARAM         - Get parameter
                 PARAM=        - Clear parameter
                 PARAM^=       - Set parameter to empty string
                 PARAM=VALUE   - Set parameter
                 <hash ref>    - Set entire UserParam hash lookup
                 undef         - Clear all user parameters

               Where PARAM is the user-defined parameter name (case insensitive).

               User-defined parameters may be accessed in tag name expressions by prefixing the  parameter  name
               with    a    dollar    sign    just   like   normal   tags,   or   via   the   API   by   calling
               "Options('UserParam','PARAM')".  Appending a hash tag ("#") to the parameter name also causes the
               parameter to be extracted as a normal tag (in the UserParam group).  If called without additional
               arguments, Options('UserParam') returns a reference to the hash  of  all  user  parameters  (with
               lower-case names).

           Validate
               Flag  to  perform  extra  validation  metadata  checks when reading, causing extra warnings to be
               generated if problems are found.  Default is undef.

           Verbose
               Print verbose messages to file specified by TextOut option.   Value  may  be  from  0  to  5  for
               increasingly  verbose messages.  Default is 0.  With the verbose option set, messages are printed
               to the console as the file is parsed.  Level 1 prints the tag names and raw values.  Level 2 adds
               more details about the tags.  Level 3 adds a hex dump of the tag data, but  with  limits  on  the
               number of bytes dumped.  Levels 4 and 5 remove the dump limit on tag values and JPEG segment data
               respectively.

           WindowsLongPath
               Support   long   path   names  in  Windows.   Enabling  this  option  automatically  enables  the
               WindowsWideFile feature.  Default is 1.

           WindowsWideFile
               Force the use of wide-character Windows I/O functions.  This may be necessary when files are on a
               network drive and the current directory name contains Unicode characters.   Without  this  option
               the  wide-character  functions  are  used  only  if  the  specified  file  path  contains Unicode
               characters.

           WriteMode
               Set tag write/create mode.  Value is a string of one or more characters from list below.  Default
               is 'wcg'.

                   w - Write existing tags
                   c - Create new tags
                   g - create new Groups as necessary

               The level of the group differs for different types of metadata. For XMP or IPTC this is the  full
               XMP/IPTC  block  (the  family  0  group),  but  for EXIF this is the individual IFD (the family 1
               group).  The 'w' and 'c' modes are tested only when "SetNewValue" is called, but the 'g' mode  is
               also tested in "WriteInfo".

           XAttrTags
               Flag to extract the OS X extended attribute tags (see the "xattr" man page and "MacOS XAttr Tags"
               in Image::ExifTool::TagNames for more information).

           XMPAutoConv
               Flag  to  enable  automatic  conversion  for unknown XMP tags with values that look like rational
               numbers or dates.  Default is 1.

       Return Values:
           The original value of the last specified parameter.

   ClearOptions
       Reset all  options  to  their  default  values.   Loads  user-defined  default  option  values  from  the
       %Image::ExifTool::UserDefined::Options hash in the .ExifTool_config file if it exists.

           $exifTool->ClearOptions();

       Inputs:
           0) ExifTool object reference

       Return Values:
           (none)

   ExtractInfo
       Extract all meta information from an image.

           $success = $exifTool->ExtractInfo('image.jpg', \%options);

       Inputs:
           "ExtractInfo" takes exactly the same arguments as "ImageInfo".  The only difference is that a list of
           tag  keys is not returned if an ARRAY reference is given.  The following options are effective in the
           call to "ExtractInfo":

           Binary,   Charset,   CharsetEXIF,   CharsetFileName,   CharsetID3,   CharsetIPTC,   CharsetPhotoshop,
           CharsetQuickTime,  CharsetRIFF, Composite, ExtendedXMP, ExtractEmbedded, FastScan, FixBase, HtmlDump,
           HtmlDumpBase,  IgnoreGroups,  IgnoreMinorErrors,  IgnoreTags,  Lang,  LargeFileSupport,   MakerNotes,
           MDItemTags,  NoPDFList,  Password,  QuickTimeUTC  (enforced 1904 time zero), RequestAll, RequestTags,
           SaveBin, SaveFormat,  SavePath,  ScanForXMP,  Struct,  TextOut,  Unknown,  Verbose,  WindowsLongPath,
           WindowsWideFile, XAttrTags and XMPAutoConv.

       Return Value:
           1 if this was a recognized file format, 0 otherwise (and 'Error' tag set).

   GetInfo
       "GetInfo"  is  called to return meta information after it has been extracted from the image by a previous
       call to "ExtractInfo" or "ImageInfo". This function may be called  repeatedly  after  a  single  call  to
       "ExtractInfo" or "ImageInfo".

           # get image width and height only
           $info = $exifTool->GetInfo('ImageWidth', 'ImageHeight');

           # get all Error and Warning messages
           $info = $exifTool->GetInfo('Error', 'Warning');

           # get information for all tags in list (list updated with tags found)
           $info = $exifTool->GetInfo(\@ioTagList);

           # get all information in Author or Location groups
           $info = $exifTool->GetInfo({Group2 => ['Author', 'Location']});

       Inputs:
           Inputs  are  the  same  as  "ExtractInfo"  and "ImageInfo" except that an image can not be specified.
           Options in effect are:

           Charset, CoordFormat, DateFormat, Duplicates, Escape, Exclude, Filter, Group#, GlobalTimeShift, Lang,
           ListItem, ListJoin, PrintConv, Sort (if a tag list reference is given) and StrictDate.

       Return Value:
           Reference to information hash, the same as with "ImageInfo".

       The following options are effective in the call to "GetInfo":

       Charset, CoordFormat, DateFormat, Duplicates, Escape, Exclude,  Filter,  Group#,  GlobalTimeShift,  Lang,
       ListItem,  ListJoin, PrintConv, QuickTimeUTC (conversion to local time), Sort (if a tag list reference is
       given) and StrictDate.

   WriteInfo
       Write meta information to a file.  The specified source file is rewritten to  the  same-type  destination
       file with new information as specified by previous calls to "SetNewValue".  The necessary segments and/or
       directories  are  created in the destination file as required to store the specified information.  May be
       called repeatedly  to  write  the  same  information  to  additional  files  without  the  need  to  call
       "SetNewValue" again.

       ExifTool  queues  all  new  values that are assigned via calls to "SetNewValue", then applies them to any
       number of files through one or more calls to "WriteInfo". These queued values  may  be  accessed  through
       "GetNewValue",  and  are  completely  separate  from  metadata  extracted from files via "ExtractInfo" or
       "ImageInfo" and accessed through "GetInfo" or "GetValue".

       To be clear, it is NOT necessary to call "ExtractInfo" or "ImageInfo"  before  "WriteInfo".   "WriteInfo"
       changes only metadata specified by previous calls to "SetNewValue".

           # add information to a source file, writing output to new file
           $exifTool->WriteInfo($srcfile, $dstfile);

           # create XMP data file from scratch
           $exifTool->WriteInfo(undef, $dstfile, 'XMP');

           # overwrite file (you do have backups, right?)
           $exifTool->WriteInfo($srcfile);

       Inputs:
           0) ExifTool object reference

           1)  Source  file  name,  file reference, scalar reference, or undef to create a file from scratch.  A
           reference to a File::RandomAccess object  is  also  allowed  as  a  source,  but  in  this  case  the
           destination is not optional.

           2) [optional] Destination file name, file reference, scalar reference to write to memory, or undef to
           overwrite the original file.  May be '-' to write to stdout.

           3) [optional] Destination file type.  Ignored if a source is defined.

       Return Value:
           1 if file was written OK, 2 if file was written but no changes made, 0 on file write error.

           If  an  error code is returned, an Error tag is set and GetValue('Error') can be called to obtain the
           error description.  A Warning tag may be set even if this routine is successful.   Calling  WriteInfo
           clears any pre-existing Error and Warning tags.

               $errorMessage = $exifTool->GetValue('Error');
               $warningMessage = $exifTool->GetValue('Warning');

       Notes:
           The  source  file  name may be undefined to create a file from scratch (currently only XMP, MIE, ICC,
           VRD, DR4, EXV and EXIF files can be created  in  this  way  --  see  "CanCreate"  for  details).   If
           undefined, the destination file type is required unless the type can be determined from the extension
           of the destination file name.

           If  a  destination  file  name  is  given,  the  specified  file  must  not exist because an existing
           destination file will not be overwritten.  Any new values for FileName,  Directory  or  HardLink  are
           ignored when a destination file name is specified.

           The  destination  file  name  may  be  undefined  to  overwrite the original file (make sure you have
           backups!).  In this case, if a source file name is provided, a temporary file is created and  renamed
           to  replace  the  source  file  if  no  errors  occurred  while writing.  Otherwise, if a source file
           reference or scalar reference is used, the image is first written  to  memory  then  copied  back  to
           replace the original if there were no errors.

           On  Mac  OS systems, the file resource fork is preserved if this routine is called with a source file
           name.

       The following ExifTool options are effective in the call to "WriteInfo":

       ByteOrder,   Charset,   CharsetEXIF,   CharsetFileName,   CharsetIPTC,   Compact,   Compress,    FixBase,
       IgnoreMinorErrors,   NoMultiExif,   NoPDFList,   Password,   QuickTimeHandler,   QuickTimePad,   Verbose,
       WindowsLongPath, WindowsWideFile and WriteMode.

   GetTagList
       Get a sorted list of tags from the specified information hash or tag list.

           @tags = $exifTool->GetTagList($info, 'Group0');

       Inputs:
           0) ExifTool object reference

           1) [optional] Information hash reference or tag list reference

           2) [optional] Sort order ('Input', 'File', 'Tag', 'Descr' or 'Group#')

           3) [optional] Secondary sort order ('File', 'Tag' or 'Descr')

           If the information hash or tag list reference is not provided, then the list of found tags  from  the
           last  call  to "ImageInfo", "ExtractInfo" or "GetInfo" is used instead, and the result is the same as
           if "GetFoundTags" was called.  If sort order is not specified, the  sort  order  is  taken  from  the
           current options settings.

       Return Values:
           A list of tag keys in the specified order.

   GetFoundTags
       Get list of found tags in specified sort order.  The found tags are the tags for the information obtained
       from the most recent call to "ImageInfo", "ExtractInfo" or "GetInfo" for this object.

           @tags = $exifTool->GetFoundTags('File');

       Inputs:
           0) ExifTool object reference

           1) [optional] Sort order ('Input', 'File', 'Tag', 'Descr' or 'Group#')

           2) [optional] Secondary sort order ('File', 'Tag' or 'Descr')

           If sort order is not specified, the sort order from the ExifTool options is used.

       Return Values:
           A list of tag keys in the specified order.

   GetRequestedTags
       Get  list  of requested tags.  These are the tags that were specified in the arguments of the most recent
       call to "ImageInfo", "ExtractInfo" or "GetInfo", including tags  specified  via  a  tag  list  reference.
       Shortcut tags are expanded in the list.

           @tags = $exifTool->GetRequestedTags();

       Inputs:
           (none)

       Return Values:
           List  of requested tag keys in the same order that the tags were specified.  Note that this list will
           be empty if tags were not specifically requested (ie. If extracting all tags).

   GetValue
       Get the value of a specified tag.  The returned value is either the human-readable (PrintConv) value, the
       converted machine-readable (ValueConv) value, the original raw (Raw)  value,  or  the  original  rational
       (Rational)  value  for  rational  formats.   If  the  value type is not specified, the PrintConv value is
       returned if the PrintConv option is set, otherwise the ValueConv value is returned.  The PrintConv values
       are same as the values returned by "ImageInfo" and "GetInfo" in the tag/value hash unless  the  PrintConv
       option is disabled.

       Tags  which  represent  lists  of multiple values (as may happen with 'Keywords' for example) are handled
       specially.  In scalar context, the returned PrintConv value for these tags is either a string  of  values
       or  a list reference (depending on the ListJoin option setting), and the ValueConv value is always a list
       reference.  But in list context, "GetValue" always returns the list itself.

       Note that "GetValue" requires a case-sensitive tag key as an argument.  To retrieve tag information based
       on a case-insensitive tag name (with an optional group specifier), use "GetInfo" instead.

           # PrintConv example
           my $val = $exifTool->GetValue($tag);
           if (ref $val eq 'SCALAR') {
               print "$tag = (unprintable value)\n";
           } else {
               print "$tag = $val\n";
           }

           # ValueConv examples
           my $val = $exifTool->GetValue($tag, 'ValueConv');
           if (ref $val eq 'ARRAY') {
               print "$tag is a list of values\n";
           } elsif (ref $val eq 'SCALAR') {
               print "$tag represents binary data\n";
           } else {
               print "$tag is a simple scalar\n";
           }

           my @keywords = $exifTool->GetValue('Keywords', 'ValueConv');

       The following options are in effect when "GetValue" is called:

       Charset, CoordFormat, DateFormat, Escape, Filter, GlobalTimeShift, Lang, ListItem,  ListJoin,  PrintConv,
       QuickTimeUTC (conversion to local time), StrictDate and TimeZone.

       Inputs:
           0) ExifTool object reference

           1) Tag key, or case-sensitive tag name with optional group prefix(es)

           2) [optional] Value type: 'PrintConv', 'ValueConv', 'Both', 'Raw', 'Bin' or 'Rational'

           The  default  value  type  is  'PrintConv'  if  the PrintConv option is set, otherwise the default is
           'ValueConv'.  A value type of 'Both' returns both ValueConv and PrintConv values as  a  list.   'Raw'
           returns  the  raw  decoded  tag  value.   'Bin' returns the original binary data for EXIF tags if the
           "SaveBin" option was set.  'Rational' returns the  raw  rational  value  as  a  string  fraction  for
           rational types, or undef for other types.

       Return Values:
           The  value  of  the  specified tag.  If the tag represents a list of multiple values and the ListJoin
           option is enabled then PrintConv returns a string of values, otherwise a reference  to  the  list  is
           returned  in  scalar context. The list itself is returned in list context.  (Unless 'Both' values are
           requested, in which case two list references are returned, regardless of context.)  Values  may  also
           be scalar references to binary data, or hash references if the "Struct" option is set.

           Note:  It is possible for "GetValue" to return an undefined ValueConv or PrintConv value (or an empty
           list in list context) even if the tag exists, since it is possible for  these  conversions  to  yield
           undefined  values.  And the Rational value will be undefined for any non-rational tag.  The Raw value
           should always exist if the tag exists.

   SetNewValue
       Set the new value for a tag.  The routine may be called multiple times to set the  values  of  many  tags
       before  using "WriteInfo" to write the new values to an image.  These values remain queued for writing to
       subsequent files until "SetNewValue" is called without arguments to reset the queued values.

       For list-type tags (like Keywords), either call repeatedly with the same tag name for each value, or call
       with a reference to the list of values.

           # set a new value for a tag (errors go to STDERR)
           $success = $exifTool->SetNewValue($tag, $value);

           # set a new value and capture any error message
           ($success, $errStr) = $exifTool->SetNewValue($tag, $value);

           # delete information for specified tag if it exists in image
           # (also resets AddValue and DelValue options for this tag)
           $exifTool->SetNewValue($tag);

           # reset all values from previous calls to SetNewValue()
           $exifTool->SetNewValue();

           # delete a specific keyword
           $exifTool->SetNewValue('Keywords', $word, DelValue => 1);

           # set keywords (a list-type tag) with two new values
           $exifTool->SetNewValue(Keywords => 'word1');
           $exifTool->SetNewValue(Keywords => 'word2');
           # equivalent, but set both in one call using an array reference
           $exifTool->SetNewValue(Keywords => ['word1','word2']);

           # add a keyword without replacing existing keywords in the file
           $exifTool->SetNewValue(Keywords => $word, AddValue => 1);

           # conditionally add a tag if it didn't exist before,
           # or replace it if it had a specified value ("old value")
           $exifTool->SetNewValue(Description => '', DelValue => 1);
           $exifTool->SetNewValue(Description => 'old value', DelValue => 1);
           $exifTool->SetNewValue(Description => 'new value');

           # set a tag in a specific group
           $exifTool->SetNewValue(Headline => $val, Group => 'XMP');
           $exifTool->SetNewValue('XMP:Headline' => $val);  # (equivalent)

           # shift original date/time back by 2.5 hours
           $exifTool->SetNewValue(DateTimeOriginal => '2:30', Shift => -1);

           # write a tag only if it had a specific value
           # (the order of the following calls is not significant)
           $exifTool->SetNewValue(Title => $oldVal, DelValue => 1);
           $exifTool->SetNewValue(Title => $newVal);

           # write tag by numerical value
           $exifTool->SetNewValue(Orientation => 6, Type => 'ValueConv');
           $exifTool->SetNewValue('Orientation#' => 6);  # (equivalent)

           # delete all but EXIF tags
           $exifTool->SetNewValue('*');  # delete all...
           $exifTool->SetNewValue('EXIF:*', undef, Replace => 2); # ...but EXIF

           # write structured information as a HASH reference
           $exifTool->SetNewValue('XMP:Flash' => {
               mode   => 'on',
               fired  => 'true',
               return => 'not'
           });

           # write structured information as a serialized string
           $exifTool->SetNewValue('XMP:Flash'=>'{mode=on,fired=true,return=not}');

       (See <https://exiftool.org/struct.html#Serialize>  for  a  description  of  the  structure  serialization
       technique.)

       Inputs:
           0) ExifTool object reference

           1) [optional] Tag key or tag name, or undef to clear all new values.  The tag name may be prefixed by
           one  or  more  family 0, 1 or 2 group names with optional leading family numbers, separated by colons
           (eg. 'EXIF:Artist', 'XMP:Time:*'), which is equivalent to using a Group option argument.  Also, a '#'
           may be appended to the tag name (eg. 'EXIF:Orientation#'), with the same effect as  setting  Type  to
           'ValueConv'.   Wildcards  ('*' and '?') may be used in the tag name to assign or delete multiple tags
           simultaneously.  A tag name of '*' is special when deleting information, and will  delete  an  entire
           group  even if some individual tags in the group are not writable, but only if a single family 0 or 1
           group is specified (otherwise the tags are deleted individually).  Use  "GetDeleteGroups"  to  get  a
           list of deletable group names, and see Image::ExifTool::TagNames for a complete list of tag names.

           2)  [optional]  New  value  for  tag.   Undefined  to  delete tag from file.  May be a scalar, scalar
           reference, list reference to set a list of values, or hash reference for a structure.  Integer values
           may be specified as a hexadecimal string (with a leading '0x'), and simple  rational  values  may  be
           specified  in  fractional  form  (eg.  '4/10').   Structure  tags  may  be specified either as a hash
           reference or a serialized string (see the last two examples above).

           3-N) [optional] SetNewValue option/value pairs (see below).

       SetNewValue Options:
           AddValue
               Specifies that the value be added to an existing list in  a  file  rather  than  overwriting  the
               existing  values.  Valid settings are 0 (overwrite any existing tag value), 1 (add to an existing
               list and warn for non-list tags) or 2  (add  to  existing  list  and  overwrite  non-list  tags).
               Default is 0.

           DelValue
               Delete existing tag from a file if it has the specified value.  For list-type tags this deletes a
               specified  item from the list.  For non-list tags this may be used to conditionally replace a tag
               by providing a new value in a separate call to SetNewValue (see examples above).  For  structured
               tags,  the  entire  structure  is  deleted/replaced only if all of the specified fields match the
               existing structure.  Option values are 0 or 1.  Default is 0.

           EditGroup
               Create tags in existing groups only.  Don't  create  new  group.   Valid  values  are  0  and  1.
               Effectively removes the 'g' from the ExifTool WriteMode option for this tag only.  Default is 0.

           EditOnly
               Edit  tag  only  if  it  already  exists.   Don't  create  new  tag.   Valid  values are 0 and 1.
               Effectively removes the 'c' from the ExifTool WriteMode option for this tag only.  Default is 0.

           Group
               Specifies group name where tag should be  written.   This  option  is  superseded  by  any  group
               specified  in  the  tag  name.   If  not  specified,  tag is written to highest priority group as
               specified by "SetNewGroups".  May be one or more family 0, 1 or 2 groups  with  optional  leading
               family number, separated by colons.  Case is not significant.

           NoFlat
               Treat flattened tags as 'unsafe'.

           NoShortcut
               Disables default behaviour of looking up tag in shortcuts if not found otherwise.

           Protected
               Bit  mask for tag protection levels to write.  Bit 0x01 allows writing of 'unsafe' tags (ie. tags
               not copied automatically via "SetNewValuesFromFile").  Bit 0x02  allows  writing  of  'protected'
               tags,  and should only be used internally by ExifTool.  See Image::ExifTool::TagNames, for a list
               of tag names indicating 'unsafe' and 'protected' tags.  Default is 0.

           ProtectSaved
               Avoid setting new values which were saved after the Nth call to "SaveNewValues".  Has  no  effect
               on unsaved values, or values saved before Nth call.  Option value is N.  Default is undef.

           Replace
               Flag  to  replace  the  previous  new values for this tag (ie. replace the values set in previous
               calls to "SetNewValue").  This option is most commonly used to replace previously-set new  values
               for  list-type  tags.  Valid values are 0 (set new value normally -- adds to new values for list-
               type tags), 1 (reset any previous new values before setting new value) or 2 (reset  previous  new
               values only; new value argument is ignored).  Default is 0.

           Shift
               Shift  the  tag  by  the  specified value.  Currently only date/time tags and tags with numerical
               values may be shifted.  Undefined for no shift, 1 for a positive shift,  or  -1  for  a  negative
               shift.   A  value of 0 causes a positive shift to be applied if the tag is shiftable and AddValue
               is set, or a negative shift for date/time tags only if DelValue is set. Default  is  undef.   See
               Image::ExifTool::Shift(3pm) for more information.

           Type
               The type of value being set.  Valid values are PrintConv, ValueConv or Raw.  Default is PrintConv
               if the "PrintConv" Option is set, otherwise ValueConv.

       Return Values:
           In  scalar context, returns the number of tags set and error messages are printed to STDERR.  In list
           context, returns the number of tags set, and the error string (which is undefined  if  there  was  no
           error).

       Notes:
           When  deleting  groups of tags, the Replace option may be used to exclude specific groups from a mass
           delete.  However, this technique may not be used to exclude  individual  tags  from  a  group  delete
           (unless  a  family  2  group  was  specified  in the delete).  Instead, use "SetNewValuesFromFile" to
           recover the values of individual tags after deleting a group.

           When deleting all tags from a JPEG image, the APP14 "Adobe" information is  not  deleted  by  default
           because doing so may affect the appearance of the image.  However, this information may be deleted by
           specifying it explicitly, either by group (with 'Adobe:*') or as a block (with 'Adobe').

       The following ExifTool options are effective in the call to "SetNewValue":

       Charset,  DateFormat,  Escape,  IgnoreMinorErrors,  Lang,  ListJoin,  ListSplit, PrintConv, QuickTimeUTC,
       StrictDate, TimeZone, Verbose and WriteMode.

   GetNewValue
       Get the new Raw value for a tag.  This is the value set by "SetNewValue" this is queued to be written  to
       file.  List-type tags may return multiple values in list context.

           $rawVal = $exifTool->GetNewValue($tag);

           @rawVals = $exifTool->GetNewValue($tag);

       Notes:
           The  API  NoDups  option applies when this routine is called, and removes duplicate items from values
           returned for List-type tags.

       Inputs:
           0) ExifTool object reference

           1) Tag name (case sensitive, may be prefixed by family 0, 1 or 7 group names, separated by colons)

       Return Values:
           List of new Raw tag values, or first value in list when called in scalar context.  The  list  may  be
           empty  either  if  the  tag  isn't being written, or if it is being deleted (ie. if "SetNewValue" was
           called without a value).

   SetNewValuesFromFile
       A very powerful routine that sets new values for tags from information found in a specified file.

           # set new values from all information in a file...
           my $info = $exifTool->SetNewValuesFromFile($srcFile);
           # ...then write these values to another image
           my $result = $exifTool->WriteInfo($file2, $outFile);

           # set all new values, preserving original groups
           $exifTool->SetNewValuesFromFile($srcFile, '*:*');

           # set specific information
           $exifTool->SetNewValuesFromFile($srcFile, @tags);

           # set new value from a different tag in specific group
           $exifTool->SetNewValuesFromFile($fp, 'XMP-dc:Subject<IPTC:Keywords');

           # add all IPTC keywords to XMP subject list
           $exifTool->SetNewValuesFromFile($fp, 'XMP-dc:Subject+<IPTC:Keywords');

           # set new value from an expression involving other tags
           $exifTool->SetNewValuesFromFile($file,
               'Comment<ISO=$ISO Aperture=$aperture Exposure=$shutterSpeed');

           # set keywords list from the values of multiple tags
           $exifTool->SetNewValuesFromFile($file, { Replace => 0 },
               'keywords<xmp:subject', 'keywords<filename');

           # copy all EXIF information, preserving the original IFD
           # (without '*.*<' tags would be copied to the preferred EXIF IFD)
           $exifTool->SetNewValuesFromFile($file, '*:*<EXIF:*');

           # copy all tags with names starting with "gps" (note: this is
           # different than "gps:*" because it will also copy XMP GPS tags)
           $exifTool->SetNewValuesFromFile($file, 'gps*');

           # set FileName from Model, translating questionable characters
           $exifTool->SetNewValuesFromFile($file,
               'filename<${model; tr(/\\\\?*:|"><)(_) }.jpg');

       Inputs:
           0) ExifTool object reference

           1) File name, file reference, or scalar reference

           2-N) [optional] List of tag names to set or options hash references.  All writable tags  are  set  if
           none  are specified.  The tag names are not case sensitive, and may be prefixed by one or more family
           0, 1, 2 or 7 group names with optional leading family numbers, separated by colons (eg.  'exif:iso').
           A leading '-' indicates tags to be excluded (eg. '-comment'), or a trailing '#' causes the  ValueConv
           value to be copied (same as setting the Type option to 'ValueConv' for this tag only).  A leading '+'
           sets  the Replace option to 0 on a per-tag basis (see Options below).  Wildcards ('*' and '?') may be
           used in the tag name.  A tag name of '*' is commonly used when a group is specified to copy all  tags
           in the group (eg. 'XMP:*').

           A  special  feature allows tag names of the form 'DSTTAG<SRCTAG' (or 'SRCTAG>DSTTAG') to be specified
           to copy information to a tag with a different name or a specified group.  Both 'SRCTAG' and  'DSTTAG'
           may  contain  wildcards  and/or  be  prefixed  by  a  group name (eg.  'fileModifyDate<modifyDate' or
           'xmp:*<*'), and/or suffixed by a '#' to disable print conversion.  Copied tags may also be  added  or
           deleted  from  a  list  with  arguments  of  the form 'DSTTAG+<SRCTAG' or 'DSTTAG-<SRCTAG'.  Tags are
           evaluated in order, so exclusions apply only to tags included earlier in the list.  An  extension  of
           this  feature  allows  the  tag  value  to be set from a string containing tag names with leading '$'
           symbols (eg. 'Comment<the file is $filename').  Braces '{}' may be used around a tag name to separate
           it from subsequent text, and a '$$' is used to to represent a '$' symbol.  The behaviour for  missing
           tags  in  expressions  is defined by the "MissingTagValue" option.  The tag value may be modified via
           changes to the default input variable ($_) in a Perl expression placed inside the braces and after  a
           semicolon following the tag name (see the last example above).  A '@' may be added after the tag name
           (before  the  semicolon)  to  make  the  expression  act  on  individual  list  items  instead of the
           concatenated string for list-type tags.  The expression has access to the full ExifTool  API  through
           the  current  ExifTool  object  ($self) and the tag key ($tag).  Braces within the expression must be
           balanced.

           Multiple options hash references may be passed to set different options for different tags.   Options
           apply to subsequent tags in the argument list.

           By  default,  this  routine  will  commute  information  between same-named tags in different groups,
           allowing information to be translated between images with different formats.  This behaviour  may  be
           modified  by  specifying  a  group  name for extracted tags (even if '*' is used as a group name), in
           which case the information is written to the original group, unless redirected to a different  group.
           When  '*'  is  used for a group name, by default the family 1 group of the original tag is preserved,
           but a different family may be specified with a leading family number.  (For example, specifying '*:*'
           copies all information while preserving the original family 1  groups,  while  '0*:*'  preserves  the
           family 0 group.)

       SetNewValuesFromFile Options:
           The  options are the same was for "SetNewValue", and are passed directly to "SetNewValue" internally,
           with a few exceptions:

           - The Replace option defaults to 1 instead of 0 as with "SetNewValue", however the tag name  argument
           may be prefixed with '+' to set the Replace option to 0 for this argument only.

           -  The  AddValue  or DelValue option is set for individual tags if '+>' or '->' (or '+<' or '-<') are
           used.

           - The Group option is set for tags where a group name is given.

           - The Protected flag is set to 1 for individually specified tags.

           - The Type option also applies to extracted tags.

       Return Values:
           A hash of information that was set successfully.  May include Warning or Error entries if there  were
           problems reading the input file.

       Notes:
           The  PrintConv  option  applies  to  this  routine, but it normally should be left on to provide more
           reliable transfer of information between groups.

           If a preview image exists, it is not copied.  The preview image must  be  transferred  separately  if
           desired, in a separate call to "WriteInfo"

           When  simply  copying  all  information  between  files  of the same type, it is usually desirable to
           preserve the original groups by specifying '*:*' for the tags to set.

           The "Duplicates" option is always in effect for tags  extracted  from  the  source  file  using  this
           routine.

           The  "Struct"  option  is  enabled  by  default  for tags extracted by this routine.  This allows the
           hierarchy of complex structures to be preserved when copying, but the Struct option may be set  to  0
           to override this behaviour and copy as flattened tags instead.

   CountNewValues
       Return the total number of new values set.

           $numSet = $exifTool->CountNewValues();
           ($numSet, $numPseudo) = $exifTool->CountNewValues();

       Inputs:
           0) ExifTool object reference

       Return Values:
           In  scalar  context,  returns  the  total  number of tags with new values set.  In list context, also
           returns the number of "pseudo" tag values which have been set.  "Pseudo" tags are tags like  FileName
           and  FileModifyDate  which are not contained within the file and can be changed without rewriting the
           file.

   SaveNewValues
       Save state of new values to be later restored by "RestoreNewValues".

           $exifTool->SaveNewValues();         # save state of new values
           $exifTool->SetNewValue(ISO => 100); # set new value for ISO
           $exifTool->WriteInfo($src, $dst1);  # write ISO + previous new values
           $exifTool->RestoreNewValues();      # restore previous new values
           $exifTool->WriteInfo($src, $dst2);  # write previous new values only

       Inputs:
           0) ExifTool object reference

       Return Value:
           Count of the number of times this routine has been called (N) since the last time the new values were
           reset.

   RestoreNewValues
       Restore new values to the settings that existed when "SaveNewValues" was  last  called.   May  be  called
       repeatedly after a single call to "SaveNewValues".  See "SaveNewValues" above for an example.

       Inputs:
           0) ExifTool object reference

       Return Value:
           None.

   SetAlternateFile
       Specify  alternate  file  from  which to read metadata.  Tags from the alternate file are available after
       "ExtractInfo" is called or during a call to "SetNewValuesFromFile" by using a family 8  group  name  (eg.
       'File1' in the example below).

           $exifTool->SetAlternateFile(File1 => 'images/test1.jpg');

       Inputs:
           0) ExifTool object reference

           1) Family 8 group name, case insensitive (eg. 'File1', 'File2'...)

           2) Name of alternate input file, or undef to reset

       Return Values:
           1 on success, or 0 if the group name is invalid.

   SetFileModifyDate
       Write  the  filesystem  modification  or  creation  time  from  the  new  value  of the FileModifyDate or
       FileCreateDate tag.

           $exifTool->SetNewValue(FileModifyDate => '2000:01:02 03:04:05-05:00',
                                  Protected => 1);
           $result = $exifTool->SetFileModifyDate($file);

       Inputs:
           0) ExifTool object reference

           1) File name

           2) [optional] Base time if applying shift (days before $^T)

           3) [optional] Tag to write: 'FileModifyDate' (default), or 'FileCreateDate'

       Return Value:
           1 if the time was changed, 0 if nothing was done, or -1 if there was an error setting the time.

       Notes:
           Equivalent to,  but  more  efficient  than  calling  "WriteInfo"  when  only  the  FileModifyDate  or
           FileCreateDate  tag  has  been  set.   If  a  timezone is not specified, local time is assumed.  When
           shifting, the time of the original file is used unless the optional base time is specified.

           The ability to write FileCreateDate is currently restricted to Windows systems only.

   SetFileName
       Set the file name and directory, or create a hard link.  If not specified, the new file name  is  derived
       from the new values of the FileName and Directory tags, or from the HardLink or SymLink tag if creating a
       link.   If  the  FileName tag contains a '/', then the file is renamed into a new directory.  If FileName
       ends with '/', then it is taken as a directory name and the file is moved into the  new  directory.   The
       new value for the Directory tag takes precedence over any directory specified in FileName.

           $result = $exifTool->SetFileName($file);
           $result = $exifTool->SetFileName($file, $newName);

       Inputs:
           0) ExifTool object reference

           1) Current file name

           2) [optional] New file name

           3) [optional] 'HardLink' or 'SymLink' to create a hard or symbolic link instead of renaming the file,
           or 'Test' to test renaming feature by printing the old and new names instead of changing anything.

       Return Value:
           1  on  success,  0 if nothing was done, or -1 if there was an error renaming the file or creating the
           link.

       Notes:
           Will not overwrite existing files. New  directories  are  created  as  necessary.   If  the  file  is
           successfully renamed, the new file name may be accessed via $$exifTool{NewName}.

   SetNewGroups
       Set the order of the preferred groups when adding new information.  In subsequent calls to "SetNewValue",
       new  information  will  be created in the first valid group of this list.  This has an impact only if the
       group is not specified when calling "SetNewValue" and if the tag name exists in more than one group.  The
       default order is EXIF, IPTC, XMP, MakerNotes, QuickTime, Photoshop, ICC_Profile,  CanonVRD,  Adobe.   Any
       family 0 group name may be used.  Case is not significant.

           $exifTool->SetNewGroups('XMP','EXIF','IPTC');

       Inputs:
           0) ExifTool object reference

           1-N)  Groups  in  order  of  priority.   If  no groups are specified, the priorities are reset to the
           defaults.

       Return Value:
           None.

   GetNewGroups
       Get current group priority list.

           @groups = $exifTool->GetNewGroups();

       Inputs:
           0) ExifTool object reference

       Return Values:
           List of group names in order of write priority.  Highest priority first.

   GetTagID
       Get the ID for the specified tag.  The ID is the IFD tag number in EXIF information, the property name in
       XMP information, or the data offset in a binary data block.  For some tags, such as Composite tags  where
       there  is  no ID, an empty string is returned.  In list context, also returns a language code for the tag
       if available and different from the default language (eg.  with alternate language entries for XMP "lang-
       alt" tags).

           $id = $exifTool->GetTagID($tag);
           ($id, $lang) = $exifTool->GetTagID($tag);

       Inputs:
           0) ExifTool object reference

           1) Tag key

       Return Values:
           In scalar context, returns the tag ID or '' if there is no ID for this tag.  In list context, returns
           the tag ID (or '') and the language code (or undef).

   GetDescription
       Get description for specified tag.  This function will always return a defined value.  In the case  where
       the description doesn't exist, one is generated from the tag name.

       Inputs:
           0) ExifTool object reference

           1) Tag key

       Return Values:
           A description for the specified tag.

   GetGroup
       Get group name(s) for a specified tag.

           # return family 0 group name (eg. 'EXIF');
           $group = $exifTool->GetGroup($tag, 0);

           # return all groups (eg. qw{EXIF IFD0 Author Main})
           @groups = $exifTool->GetGroup($tag);

           # return groups as a string (eg. 'Main:IFD0:Author')
           $group = $exifTool->GetGroup($tag, ':3:1:2');

           # return groups as a simplified string (eg. 'IFD0:Author')
           $group = $exifTool->GetGroup($tag, '3:1:2');

       Inputs:
           0) ExifTool object reference

           1) Tag key

           2) [optional] Group family number, or string of numbers separated by colons

       Return Values:
           Group name (or '' if tag has no group).  If no group family is specified, "GetGroup" returns the name
           of  the  group  in family 0 when called in scalar context, or the names of groups for all families in
           list context.  Returns a string of group names separated by colons if the input group family contains
           a colon.  The string is simplified to remove a leading 'Main:' and  adjacent  identical  group  names
           unless the family string begins with a colon.

       Notes:
           The group family numbers are currently available:

               0) Information Type         (eg. EXIF, XMP, IPTC)
               1) Specific Location        (eg. IFD0, XMP-dc)
               2) Category                 (eg. Author, Time)
               3) Document Number          (eg. Main, Doc1, Doc3-2)
               4) Instance Number          (eg. Copy1, Copy2, Copy3...)
               5) Metadata Path            (eg. JPEG-APP1-IFD0-ExifIFD)
               6) EXIF/TIFF Format         (eg. int8u, int32u, undef, string)
               7) Tag ID                   (eg. ID-271, ID-rights, ID-a9aut)
               8) Alternate File Number    (eg. File1, File2, File3...)

           Families  0  and  1  are  based  on  the file structure, and are similar except that family 1 is more
           specific and sub-divides some groups to give more  detail  about  the  specific  location  where  the
           information was found.  For example, the EXIF group is split up based on the specific IFD (Image File
           Directory),  the  MakerNotes group is divided into groups for each manufacturer, and the XMP group is
           separated based on the XMP namespace prefix.  Note that only common XMP namespaces are listed in  the
           GetAllGroups  documentation,  but  additional  namespaces may be present in some XMP data.  Also note
           that the 'XMP-xmp...'  group names may appear in  the  older  form  'XMP-xap...'  since  these  names
           evolved  as the XMP standard was developed.  The ICC_Profile group is broken down to give information
           about the specific ICC_Profile tag from which multiple values were extracted.  As  well,  information
           extracted from the ICC_Profile header is separated into the ICC-header group.

           Family 2 classifies information based on the logical category to which the information refers.

           Family  3  gives  the  document number for tags extracted from embedded documents, or 'Main' for tags
           from the main document.   (See  the  "ExtractEmbedded"  option  for  extracting  tags  from  embedded
           documents.)   Nested  sub-documents (if they exist) are indicated by numbers separated with dashes in
           the group name, to an arbitrary depth. (eg. 'Doc2-3-1' is the 1st sub-sub-document of  the  3rd  sub-
           document  of  the  2nd  embedded  document  of  the  main  file.)   Document numbers are also used to
           differentiate samples for timed metadata in videos.

           Family 4 provides a method for differentiating tags when multiple tags exist with the  same  name  in
           the  same  location.   The primary instance of a tag (the tag extracted when the Duplicates option is
           disabled and no group is specified) has no family 4 group name, but additional instances have  family
           4  group  names  of  'Copy1',  'Copy2',  'Copy3',  etc.  For convenience, the primary tag may also be
           accessed using a group name of 'Copy0'.

           Family 5 is experimental, and gives the complete path for the metadata in the file.   Generated  only
           if the "SavePath" option is used when extracting.

           Family  6  is  currently used only for EXIF/TIFF metadata, and gives the format type of the extracted
           value.  Generated only if the "SaveFormat" option is used when extracting.

           Family 7 is used for tag ID's.  The group names are the actual tag ID's, with a leading "ID-" string.
           Non-numerical ID's have characters other than [-_A-Za-z0-9] converted to hex.  Numerical tag ID's are
           returned in hex if the "HexTagIDs" option is set, otherwise  decimal  is  used.   When  specifying  a
           family  7  group name, numerical ID's may be in hex or decimal, and non-numerical ID's may or may not
           have characters other than [-_A-Za-z0-9] converted to hex.  Note that unlike other group  names,  the
           tag ID's of family 7 group names are case sensitive (but the leading "ID-" is not).

           Family 8 specifies the alternate file set from a call to "SetAlternateFile".

           See "GetAllGroups [static]" for complete lists of group names.

   GetGroups
       Get list of group names that exist in the specified information.

           @groups = $exifTool->GetGroups($info, 2);
           @groups = $exifTool->GetGroups('3:1');

       Inputs:
           0) ExifTool object reference

           1) [optional] Info hash ref (default is all extracted info)

           2) [optional] Group family number, or string of numbers (default 0)

       Return Values:
           List  of group names in alphabetical order. If information hash is not specified, the group names are
           returned for all extracted information. See "GetGroup" for  an  description  of  family  numbers  and
           family number strings.

   BuildCompositeTags
       Builds composite tags from required tags.  The composite tags are convenience tags which are derived from
       the  values  of other tags.  This routine is called automatically by "ImageInfo" and "ExtractInfo" if the
       Composite option is set.

       Inputs:
           0) ExifTool object reference

       Return Values:
           (none)

       Notes:
           Tag values are calculated in alphabetical order unless a tag Require's or Desire's another  composite
           tag, in which case the calculation is deferred until after the other tag is calculated.

           Composite  tags  may need to read data from the image for their value to be determined, and for these
           "BuildCompositeTags" must be called while the  image  is  available.   This  is  only  a  problem  if
           "ImageInfo"  is  called with a filename (as opposed to a file reference or scalar reference) since in
           this case the file is closed before "ImageInfo" returns.  Here the Composite option may  be  used  so
           that "BuildCompositeTags" is called from within "ImageInfo", before the file is closed.

   AvailableOptions [static]
       Get a list of available API options. (See "Options" for option details.)

       Inputs:
           (none)

       Return Values:
           Reference  to  list  of  available options.  Each entry in the list is a list reference with 4 items:
           0=Option name, 1=Default value, 2=Description, 3=flag set if option is undocumented.

               my $opts = Image::ExifTool::<b>AvailableOptions</b>();
               foreach (@$opts) {
                   my ($optionName, $defaultValue, $description) = @$_;
                   ...
               }

   GetTagName [static]
       Get name of tag from tag key.  This is a convenience function that strips the embedded  instance  number,
       if it exists, from the tag key.

       Note:  "static"  in  the  heading  above  indicates that the function does not require an ExifTool object
       reference as the first argument.  All functions documented below are also static.

           $tagName = Image::ExifTool::GetTagName($tag);

       Inputs:
           0) Tag key

       Return Value:
           Tag name.  This is the same as the tag key but has the instance number removed.

   GetShortcuts [static]
       Get a list of shortcut tags.

       Inputs:
           (none)

       Return Values:
           List of shortcut tags (as defined in Image::ExifTool::Shortcuts).

   GetAllTags [static]
       Get list of all available tag names.

           @tagList = Image::ExifTool::GetAllTags($group);

       Inputs:
           0) [optional] Group name, or string of group names separated by colons

       Return Values:
           A list of all available tags in alphabetical order, or all tags in a specified group or  intersection
           of  groups.  The group name is case insensitive, and any group in families 0-2 may be used except for
           EXIF family 1 groups (ie. the specific IFD).

   GetWritableTags [static]
       Get list of all writable tag names.

           @tagList = Image::ExifTool::GetWritableTags($group);

       Inputs:
           0) [optional] Group name, or string of group names separated by colons

       Return Values:
           A list of all writable tags in alphabetical order.  These are the tags for which values  may  be  set
           through  "SetNewValue".   If a group name is given, returns only writable tags in specified group(s).
           The group name is case insensitive, and any group in families 0-2 may be used except for EXIF  family
           1 groups (ie. the specific IFD).

   GetAllGroups [static]
       Get list of all group names in specified family.

           @groupList = Image::ExifTool::GetAllGroups($family);

       Inputs:
           0) Group family number (0-7)

       Return Values:
           A list of all groups in the specified family in alphabetical order.

       Here is a complete list of groups for each of these families:

       Family 0 (Information Type):
           AAC,  AFCP,  AIFF,  APE, APP0, APP1, APP11, APP12, APP13, APP14, APP15, APP2, APP3, APP4, APP5, APP6,
           APP7, APP8, APP9, ASF, Audible, Canon, CanonVRD, Composite, DICOM, DNG, DV, DjVu, Ducky,  EXE,  EXIF,
           ExifTool,  FITS, FLAC, FLIR, File, Flash, FlashPix, Font, FotoStation, GIF, GIMP, GM, GeoTiff, GoPro,
           H264, HTML, ICC_Profile, ID3, IPTC, ISO, ITC, JFIF, JPEG, JSON, JUMBF, Jpeg2000,  LNK,  Leaf,  Lytro,
           M2TS, MIE, MIFF, MISB, MNG, MOI, MPC, MPEG, MPF, MXF, MakerNotes, Matroska, Meta, Ogg, OpenEXR, Opus,
           PDF,   PICT,  PLIST,  PNG,  PSP,  Palm,  PanasonicRaw,  Parrot,  PhotoCD,  PhotoMechanic,  Photoshop,
           PostScript, PrintIM, Protobuf, QuickTime, RAF, RIFF, RSRC, RTF, Radiance,  Rawzor,  Real,  Red,  SVG,
           SigmaRaw, Sony, Stim, Theora, Torrent, Trailer, VCard, Vorbis, WTV, XML, XMP, ZIP

       Family 1 (Specific Location):
           AAC,  AC3,  AFCP,  AIFF,  APE,  ASF,  AVI1,  Adobe,  AdobeCM,  AdobeDNG,  Apple, Audible, CBOR, CIFF,
           CameraIFD, Canon, CanonCustom, CanonDR4, CanonRaw, CanonVRD, Casio, Chapter#, Composite, DICOM,  DJI,
           DNG,  DV, DjVu, DjVu-Meta, Ducky, EPPIM, EXE, EXIF, ExifIFD, ExifTool, FITS, FLAC, FLIR, File, Flash,
           FlashPix, Font, FotoStation, FujiFilm, FujiIFD, GE, GIF, GIMP, GM, GPS, GSpherical, Garmin,  GeoTiff,
           GlobParamIFD,  GoPro,  GraphConv,  H264,  HP,  HTC,  HTML, HTML-dc, HTML-ncc, HTML-office, HTML-prod,
           HTML-vw96, HTTP-equiv,  ICC-chrm,  ICC-cicp,  ICC-clrt,  ICC-header,  ICC-meas,  ICC-meta,  ICC-view,
           ICC_Profile, ICC_Profile#, ID3, ID3v1, ID3v1_Enh, ID3v2_2, ID3v2_3, ID3v2_4, IFD0, IFD1, IPTC, IPTC#,
           ISO, ITC, InfiRay, Insta360, InteropIFD, ItemList, JFIF, JFXX, JPEG, JPEG-HDR, JPS, JSON, JUMBF, JVC,
           Jpeg2000,  KDC_IFD,  Keys,  Kodak, KodakBordersIFD, KodakEffectsIFD, KodakIFD, KyoceraRaw, LIGO, LNK,
           Leaf, LeafSubIFD, Leica, Lyrics3, Lytro, M-RAW, M2TS, MAC, MIE-Audio, MIE-Camera, MIE-Canon, MIE-Doc,
           MIE-Extender, MIE-Flash, MIE-GPS, MIE-Geo, MIE-Image, MIE-Lens, MIE-Main,  MIE-MakerNotes,  MIE-Meta,
           MIE-Orient,  MIE-Preview, MIE-Thumbnail, MIE-UTM, MIE-Unknown, MIE-Video, MIFF, MISB, MNG, MOBI, MOI,
           MPC, MPEG, MPF0, MPImage, MS-DOC, MXF, MacOS, MakerNotes, MakerUnknown, Matroska, MediaJukebox, Meta,
           MetaIFD, Microsoft, Minolta, MinoltaRaw, Motorola, NITF, Nextbase, Nikon, NikonCapture,  NikonCustom,
           NikonScan,  NikonSettings,  NineEdits,  Nintendo,  Ocad, Ogg, Olympus, OpenEXR, Opus, PDF, PICT, PNG,
           PNG-cICP,  PNG-pHYs,  PSP,  Palm,  Panasonic,  PanasonicRaw,  Parrot,  Pentax,   PhaseOne,   PhotoCD,
           PhotoMechanic,   Photoshop,  PictureInfo,  PostScript,  PreviewIFD,  PrintIM,  ProfileIFD,  Qualcomm,
           QuickTime, RAF, RAF2, RIFF, RMETA, RSRC, RTF, Radiance, Rawzor,  Real,  Real-CONT,  Real-MDPR,  Real-
           PROP,  Real-RA3,  Real-RA4,  Real-RA5,  Real-RJMD, Reconyx, Red, Ricoh, SEAL, SPIFF, SR2, SR2DataIFD,
           SR2SubIFD, SRF#, SVG, Samsung, Sanyo, Scalado, Sigma, SigmaRaw, Sony, SonyIDC, Stim, SubIFD,  System,
           Theora,  Torrent,  Track#,  UserData,  VCalendar, VCard, VNote, Version0, Vorbis, WTV, XML, XMP, XMP-
           DICOM, XMP-Device, XMP-GAudio, XMP-GCamera, XMP-GContainer, XMP-GCreations,  XMP-GDepth,  XMP-GFocus,
           XMP-GImage,  XMP-GPano,  XMP-GSpherical,  XMP-LImage,  XMP-MP,  XMP-MP1, XMP-PixelLive, XMP-aas, XMP-
           acdsee, XMP-acdsee-rs, XMP-album, XMP-apple-fi, XMP-ast, XMP-aux,  XMP-cc,  XMP-cell,  XMP-crd,  XMP-
           creatorAtom,  XMP-crs,  XMP-dc,  XMP-dex, XMP-digiKam, XMP-drone-dji, XMP-dwc, XMP-et, XMP-exif, XMP-
           exifEX, XMP-expressionmedia, XMP-extensis, XMP-fpv,  XMP-getty,  XMP-hdr,  XMP-hdrgm,  XMP-ics,  XMP-
           iptcCore,  XMP-iptcExt,  XMP-lr,  XMP-mediapro,  XMP-microsoft, XMP-mwg-coll, XMP-mwg-kw, XMP-mwg-rs,
           XMP-nine, XMP-panorama, XMP-pdf, XMP-pdfx,  XMP-photomech,  XMP-photoshop,  XMP-plus,  XMP-pmi,  XMP-
           prism,  XMP-prl,  XMP-prm,  XMP-pur,  XMP-rdf, XMP-sdc, XMP-swf, XMP-tiff, XMP-x, XMP-xmp, XMP-xmpBJ,
           XMP-xmpDM, XMP-xmpDSA, XMP-xmpMM, XMP-xmpNote, XMP-xmpPLUS, XMP-xmpRights, XMP-xmpTPg, ZIP, iTunes

       Family 2 (Category):
           Audio, Author, Camera, Device, Document, ExifTool, Image, Location, Other, Preview,  Printing,  Time,
           Unknown, Video

       Family 3 (Document Number):
           Doc#, Main

       Family 4 (Instance Number):
           Copy#

       Family 5 (Metadata Path):
           eg. JPEG-APP1-IFD0-ExifIFD

       Family 6 (EXIF/TIFF Format):
           int8u, string, int16u, int32u, rational64u, int8s, undef, int16s, int32s, rational64s, float, double,
           ifd, unicode, complex, int64u, int64s, ifd64

       Family 7 (Tag ID):
           ID-xxx  (Where  xxx  is  the  tag  ID.  Numerical ID's are returned in hex with a leading "0x" if the
           HexTagIDs option is set, or decimal otherwise.  Characters in non-numerical ID's which are not  valid
           in a group name are returned as 2 hex digits.)

       Family 8 (Alternate File):
           File#

       Note:   This  function may also be called as an ExifTool member function to allow the HexTagIDs option to
       be set when retrieving family 7 group names.

   GetDeleteGroups [static]
       Get list of all deletable group names.

           @delGroups = Image::ExifTool::GetDeleteGroups();

       Inputs:
           None.

       Return Values:
           A list of deletable group names in alphabetical order.  The current list of deletable group names is:

           Adobe, AFCP, APP0, APP1, APP10, APP11, APP12, APP13, APP14, APP15,  APP2,  APP3,  APP4,  APP5,  APP6,
           APP7,  APP8,  APP9,  Audio, Author, Camera, CanonVRD, CIFF, Document, Ducky, EXIF, ExifIFD, ExifTool,
           File, FlashPix, FotoStation, GlobParamIFD, GPS, ICC_Profile, IFD0, IFD1, Image, Insta360, InteropIFD,
           IPTC, ItemList, JFIF, Jpeg2000, Keys, Location,  MakerNotes,  Meta,  MetaIFD,  Microsoft,  MIE,  MPF,
           NikonCapture,  Other,  PDF,  PDF-update,  PhotoMechanic,  Photoshop, PNG, PNG-pHYs, Preview, PrintIM,
           Printing, QuickTime, RMETA, RSRC, SubIFD, Time, Trailer, UserData, Video, XML, XML-*, XMP, XMP-*

           To schedule a group for deletion, call "SetNewValue" with a tag name like 'EXIF:*' and  an  undefined
           tag value.

           Deleting a family 0 or 1 group will delete the entire corresponding block of metadata, but deleting a
           family  2  group  (eg.  Audio,  Author,  Camera, etc.)  deletes the individual tags belonging to that
           category.

           The 'Trailer' group allows all trailers in JPEG  and  TIFF-format  images  to  be  deleted  at  once,
           including unknown trailers.  Note that the JPEG "APP" groups are special, and are used only to delete
           application  segments  which  are  not associated with another deletable group. For example, deleting
           'APP14:*' will delete other APP14 segments, but not the APP14 "Adobe" segment.

   GetFileType [static]
       Get type of file given file name.

           my $type = Image::ExifTool::GetFileType($filename);
           my $desc = Image::ExifTool::GetFileType($filename, 1);

       Inputs:
           0) [optional] File name (or just an extension)

           1) [optional] Flag to return a description instead of a type.  Default is undef.  Set to  0  to  also
           return types of recognized but unsupported files (otherwise the return value for unsupported files is
           undef), or 1 to return descriptions.

       Return Value:
           A  string, based on the file extension, which indicates the basic format of the file.  Note that some
           files may be based on other formats (like many RAW  image  formats  are  based  on  TIFF).   In  list
           context,  may  return more than one file type if the file may be based on different formats.  Returns
           undef if files with this extension are not yet supported by ExifTool.  Returns a list  of  extensions
           for  all supported file types if no input extension is specified (or all recognized file types if the
           description flag is set to 0). Returns a more detailed description of the specific file  format  when
           the description flag is set.

   CanWrite [static]
       Can the specified file be written?

           my $writable = Image::ExifTool::CanWrite($filename);

       Inputs:
           0) File name or extension

       Return Value:
           True if ExifTool supports writing files of this type (based on the file extension).

   CanCreate [static]
       Can the specified file be created?

           my $creatable = Image::ExifTool::CanCreate($filename);

       Inputs:
           0) File name or extension

       Return Value:
           True if ExifTool can create files with this extension from scratch.  Currently, this can only be done
           with XMP, MIE, ICC, VRD, DR4, EXV and EXIF files.

   AddUserDefinedTags [static]
       Add  user-defined  tags  to  an existing tag table at run time.  This differs from the usual technique of
       creating user-defined tags via the %Image::ExifTool::UserDefined hash (see the  ExifTool_config  file  in
       the  Image::ExifTool  distribution)  because  it  allows  tags  to  be  added  after a tag table has been
       initialized.

           use Image::ExifTool ':Public';
           my %tags = (
               TestTagID1 => { Name => 'TestTagName1' },
               TestTagID2 => { Name => 'TestTagName2' },
           );
           my $num = AddUserDefinedTags('Image::ExifTool::PDF::Info', %tags);

       Inputs:
           0) Destination tag table name

           1-N) Pairs of tag ID / tag information hash references for the new tags

       Return Value:
           The number of tags added.

       Notes
           Pre-existing  tags  with  the  same  ID  will   be   replaced   in   the   destination   table.   See
           lib/Image/ExifTool/README  in  the  full  distribution  for  full  details on the elements of the tag
           information hash.

   OrderedKeys [static]
       Return a list of ordered keys from a tag value that is a HASH reference when the Struct option is used.

           use Image::ExifTool ':Public';
           my @keys = OrderedKeys($structRef);

       Inputs:
           0) Structure HASH reference

       Return Value:
           List of ordered keys, or sorted alphabetically if not ordered.

CHARACTER ENCODINGS

       Certain meta information formats allow coded character sets other than plain ASCII.  When  reading,  most
       known  encodings  are  converted  to  the external character set according to the "Charset" option, or to
       UTF-8 by  default.   When  writing,  the  inverse  conversions  are  performed.   Alternatively,  special
       characters may be converted to/from HTML character entities with the "Escape" HTML option.

       A  distinction  is made between the external character set visible via the ExifTool API, and the internal
       character used to store text in the metadata of a file.  These character sets may be specified separately
       as follows:

       External Character Sets:
           The encoding for tag values passed to/from ExifTool API functions is set via  the  "Charset"  option,
           which is 'UTF8' by default.

           The   encoding   of   file  names  is  specified  via  the  "CharsetFileName"  option.   By  default,
           "CharsetFileName" is not defined, and file names passed to ExifTool are used directly in calls to the
           system i/o routines (which expect UTF-8 strings on Mac/Linux, but default to the system code page  on
           Windows).   In  this  mode on Windows a warning is issued if a file name contains special characters,
           but this  warning  may  be  avoided  by  setting  "CharsetFileName"  to  an  empty  string.   Setting
           "CharsetFileName" to any other value causes file names to be converted from the specified encoding to
           one  appropriate  for the system.  In Windows this also has the effect of activating Unicode filename
           support via the special Windows wide-character i/o routines if Win32API::File is available.

           Note that setting the "WindowsWideFile"  or  "WindowsLongPath"  option  causes  "CharsetFileName"  to
           default  to  'UTF8'  in  Windows  if not defined, and "WindowsLongPath" is set by default in ExifTool
           13.07 and later.

       Internal Character Sets:
           The encodings used to store strings in the various metadata formats.  These encodings may be  changed
           for certain types of metadata via the "CharsetEXIF", "CharsetID3", "CharsetIPTC", "CharsetPhotoshop",
           "CharsetQuickTime" and "CharsetRIFF" options.

       Values  are  returned  as  byte  strings  of  encoded characters.  Perl wide characters are not used.  By
       default, most returned strings are encoded in UTF-8.  For these, Encode::decode_utf8()  may  be  used  to
       convert  to  a  sequence  of  logical  Perl  characters.   Note  that  some  settings of the PERL_UNICODE
       environment variable may be incompatible with ExifTool's character handling.

       More specific details are given below about how character coding is handled for  EXIF,  IPTC,  XMP,  PNG,
       ID3, PDF, Photoshop, QuickTime, AIFF, MIE and Vorbis information:

   EXIF
       Most  textual  information  in  EXIF  is stored in ASCII format (called "string" in the ExifTool tag name
       documentation). By default ExifTool does not convert these strings.  However,  it  is  not  uncommon  for
       applications  to  write  UTF-8  or other encodings where ASCII is expected.  To deal with these, ExifTool
       allows the internal EXIF string encoding to be specified with "CharsetEXIF",  which  causes  EXIF  string
       values  to be converted from the specified character set when reading, and stored with this character set
       when writing.  (The MWG recommends using UTF-8 encoding for EXIF strings, and in keeping  with  this  the
       MWG  module  sets  the  default  internal  EXIF string encoding to UTF-8, but note that this will have no
       effect unless the external encoding is also set to something other than the default of UTF-8.)

       A few EXIF tags (UserComment, GPSProcessingMethod and GPSAreaInformation) support a  designated  internal
       text  encoding,  with  values stored as ASCII, Unicode (UCS-2) or JIS.  When reading these tags, ExifTool
       converts Unicode and JIS to the external character set specified by the "Charset" option, or to UTF-8  by
       default.   ASCII  text is not converted. When writing, text is stored as ASCII unless the string contains
       special characters, in which case it is converted from the external character set (UTF-8 by default), and
       stored as Unicode. ExifTool writes Unicode in native EXIF byte ordering by default, but  the  byte  order
       may be specified by setting the ExifUnicodeByteOrder tag (see the Extra Tags documentation).

       The  EXIF "XP" tags (XPTitle, XPComment, etc) are always stored as little-endian Unicode (UCS-2), and are
       read and written using the specified character set.

   IPTC
       The value of  the  IPTC:CodedCharacterSet  tag  determines  how  the  internal  IPTC  string  values  are
       interpreted.  If CodedCharacterSet exists and has a value of 'UTF8' (or 'ESC % G') then string values are
       assumed  to  be stored as UTF-8, otherwise Windows Latin1 (cp1252, 'Latin') coding is assumed by default,
       but this can be changed with the "CharsetIPTC" option.  When reading, these strings are converted to  the
       character  set  specified  by the "Charset" option.  When writing, the inverse conversions are performed.
       No conversion is done if the internal (IPTC) and external (ExifTool) character sets are the  same.   Note
       that  ISO  2022  character set shifting is not supported.  Instead, a warning is issued and the string is
       not converted if an ISO 2022 shift code is encountered.  See <http://www.iptc.org/IIM/> for the  official
       IPTC specification.

       ExifTool  may be used to convert IPTC values to a different internal encoding.  To do this, all IPTC tags
       must be rewritten along with the desired value of CodedCharacterSet.  For example, the following  command
       changes  the  internal  IPTC  encoding to UTF-8 (from Windows Latin1 unless CodedCharacterSet was already
       'UTF8'):

         exiftool -tagsfromfile @ -iptc:all -codedcharacterset=utf8 a.jpg

       or from Windows Latin2 (cp1250) to UTF-8:

         exiftool -tagsfromfile @ -iptc:all -codedcharacterset=utf8 \
         -charset iptc=latin2 a.jpg

       and this command changes it back from UTF-8 to Windows Latin1 (cp1252):

         exiftool -tagsfromfile @ -iptc:all -codedcharacterset= a.jpg

       or to Windows Latin2:

         exiftool -tagsfromfile @ -iptc:all -codedcharacterset= \
         -charset iptc=latin2 a.jpg

       Unless CodedCharacterSet is 'UTF8', applications have no reliable way to  determine  the  IPTC  character
       encoding.   For  this reason, it is recommended that CodedCharacterSet be set to 'UTF8' when creating new
       IPTC.

       (Note: Here, "IPTC" Refers to the older IPTC IIM  format.   The  more  recent  IPTC  Core  and  Extension
       specifications actually use the XMP format.)

   XMP
       ExifTool  reads XMP encoded as UTF-8, UTF-16 or UTF-32, and converts them all to UTF-8 internally.  Also,
       all XML character entity references and  numeric  character  references  are  converted.   When  writing,
       ExifTool  always encodes XMP as UTF-8, converting the following 5 characters to XML character references:
       & < > ' ".  By default no further conversion is performed, however if the "Charset" option is other  than
       'UTF8' then text is converted to/from the specified character set when reading/writing.

   PNG
       PNG  TextualData  tags  are stored as tEXt, zTXt and iTXt chunks in PNG images.  The tEXt and zTXt chunks
       use ISO 8859-1 encoding, while iTXt uses UTF-8.  When reading, ExifTool converts all PNG textual data  to
       the  character  set specified by the "Charset" option.  When writing, ExifTool generates a tEXt chunk (or
       zTXt with the "Compress" option) if the text doesn't contain special characters or if Latin  encoding  is
       specified; otherwise an iTXt chunk is used and the text is converted from the specified character set and
       stored as UTF-8.

   JPEG Comment
       The  encoding  for  the  JPEG  Comment (COM segment) is not specified, so ExifTool reads/writes this text
       without conversion.

   ID3
       The ID3v1 specification officially supports only ISO  8859-1  encoding  (a  subset  of  Windows  Latin1),
       although  some applications may incorrectly use other character sets.  By default ExifTool converts ID3v1
       text from Latin to the character set specified by the "Charset"  option.   However,  the  internal  ID3v1
       charset  may  be specified with the "CharsetID3" option.  The encoding for ID3v2 information is stored in
       the file, so ExifTool converts ID3v2 text from this encoding  to  the  character  set  specified  by  the
       "Charset" option. ExifTool does not currently write ID3 information.

   PDF
       PDF  text  strings  are  stored  in either PDFDocEncoding (similar to Windows Latin1) or Unicode (UCS-2).
       When reading, ExifTool converts to the character set specified by the "Charset"  option.   When  writing,
       ExifTool  encodes  input  text  from  the  specified character set as Unicode only if the string contains
       special characters, otherwise PDFDocEncoding is used.

   Photoshop
       Some Photoshop resource names are stored as Pascal strings with unknown encoding.  By  default,  ExifTool
       assumes MacRoman encoding and converts this to UTF-8, but the internal and external character sets may be
       specified with the "CharsetPhotoshop" and "Charset" options respectively.

   QuickTime
       QuickTime  text  strings may be stored in a variety of poorly document formats. ExifTool does its best to
       decode these according to the "Charset" option setting.  For some QuickTime strings, ExifTool  assumes  a
       default encoding of MacRoman, but this may be changed with the "CharsetQuickTime" option.

   AIFF
       AIFF  strings  are  assumed to be stored in MacRoman, and are converted according to the "Charset" option
       when reading.

   RIFF
       The internal encoding of RIFF strings (eg. in AVI and WAV files) is assumed to be Latin unless  otherwise
       specified by the RIFF CSET chunk or the "CharsetRIFF" option.

   MIE
       MIE strings are stored as either UTF-8 or ISO 8859-1. When reading, UTF-8 strings are converted according
       to  the  "Charset"  option,  and ISO 8859-1 strings are never converted.  When writing, input strings are
       converted from the specified character set to UTF-8.  The resulting strings are stored as UTF-8  if  they
       contain multi-byte UTF-8 character sequences, otherwise they are stored as ISO 8859-1.

   Vorbis
       Vorbis  comments  are  stored as UTF-8, and are converted to the character set specified by the "Charset"
       option.

AUTHOR

       Copyright 2003-2024, Phil Harvey

       This library is free software; you can redistribute it and/or modify it under  the  same  terms  as  Perl
       itself.

ACKNOWLEDGEMENTS

       Many  people  have  helped  in  the  development  of  ExifTool  through  their  bug reports, comments and
       suggestions, and/or additions to the code.  See the ACKNOWLEDGEMENTS in  the  individual  Image::ExifTool
       modules  and in html/index.html of the Image::ExifTool distribution package for a list of people who have
       contributed to this project.

SEE ALSO

       exiftool(1),               Image::ExifTool::TagNames(3pm),               Image::ExifTool::Shortcuts(3pm),
       Image::ExifTool::Shift(3pm), Image::Info(3pm), Image::MetaData::JPEG(3pm)

perl v5.40.0                                       2024-12-21                               Image::ExifTool(3pm)