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 = new Image::ExifTool;
# 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, FLIR, FujiFilm, GE, 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
------------+-------------+-------------+-------------+------------
3FR r | EIP r | LA r | ORF r/w | RTF r
3G2 r/w | EPS r/w | LFP r | OTF r | RW2 r/w
3GP r/w | EPUB r | LNK r | PAC r | RWL r/w
ACR r | ERF r/w | M2TS r | PAGES r | RWZ r
AFM r | EXE r | M4A/V r/w | PBM r/w | RM r
AI r/w | EXIF r/w/c | MEF r/w | PCD r | SEQ r
AIFF r | EXR r | MIE r/w/c | PDB r | SO r
APE r | EXV r/w/c | MIFF r | PDF r/w | SR2 r/w
ARW r/w | F4A/V r/w | MKA r | PEF r/w | SRF r
ASF r | FFF r/w | MKS r | PFA r | SRW r/w
AVI r | FLA r | MKV r | PFB r | SVG r
AZW r | FLAC r | MNG r/w | PFM r | SWF r
BMP r | FLV r | MOBI r | PGF r | THM r/w
BTF r | FPF r | MODD r | PGM r/w | TIFF r/w
CHM r | FPX r | MOS r/w | PLIST r | TORRENT r
COS r | GIF r/w | MOV r/w | PICT r | TTC r
CR2 r/w | GZ r | MP3 r | PMP r | TTF r
CRW r/w | HDP r/w | MP4 r/w | PNG r/w | VRD r/w/c
CS1 r/w | HDR r | MPC r | PPM r/w | VSD r
DCM r | HTML r | MPG r | PPT r | WAV r
DCP r/w | ICC r/w/c | MPO r/w | PPTX r | WDP r/w
DCR r | IDML r | MQV r/w | PS r/w | WEBP r
DFONT r | IIQ r/w | MRW r/w | PSB r/w | WEBM r
DIVX r | IND r/w | MXF r | PSD r/w | WMA r
DJVU r | INX r | NEF r/w | PSP r | WMV r
DLL r | ITC r | NRW r/w | QTIF r/w | WV r
DNG r/w | J2C r | NUMBERS r | RA r | X3F r/w
DOC r | JNG r/w | ODP r | RAF r/w | XCF r
DOCX r | JP2 r/w | ODS r | RAM r | XLS r
DPX r | JPEG r/w | ODT r | RAR r | XLSX r
DV r | K25 r | OFR r | RAW r/w | XMP r/w/c
DVB r/w | KDC r | OGG r | RIFF r | ZIP r
DYLIB r | KEY r | OGV r | RSRC 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.
$exifTool = new Image::ExifTool;
Note that ExifTool uses AUTOLOAD to load non-member methods, so any class using
Image::ExifTool as a base class must define an AUTOLOAD which calls
Image::ExifTool::DoAutoLoad(). eg)
sub AUTOLOAD
{
Image::ExifTool::DoAutoLoad($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, the FileSize, FileModifyDate and
FilePermissions 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.)
- HASH ref
- Reference to a hash containing the options settings. 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, which are similar to the tag names
but may have 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. Lists of values are joined by commas
into a single string only if the PrintConv option is enabled and the List
option is disabled (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 = new Image::ExifTool;
$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 strings 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.
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.
# 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');
- 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:
- 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 0.
- 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.
- Charset
- Character set for encoding character strings 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
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.
- CharsetEXIF
- Internal encoding to use for stored EXIF "ASCII" string values.
Unlike other Charset options, CharsetEXIF may also be set to undef to pass
through all string values without recoding. Default is undef.
- 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'.
- Compact
- Flag to write compact output. Default is 0. The XMP specification suggests
that the data be padded with blanks to allow in-place editing. With this
flag set the 2kB of padding is not written. Note that this only effects
embedded XMP since padding is never written for stand-alone XMP
files.
- 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 Compress::Zlib is installed. Default is 0.
- 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 "+" to the format specifier (eg. "%+.6f")
prints a signed coordinate instead. 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 for details about the format string. The default is similar
to a format of "%Y:%m:%d %H:%M:%S". If date can not be
converted, value is left unchanged unless the StrictDate option is set.
Timezones are ignored.
- Duplicates
- Flag to return values from tags with duplicate names when extracting
information. Default is 1.
- 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 from tags extracted from an image. 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".
- 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, streaming metadata in AVCHD videos, and the
resource fork of Mac OS files. Default is 0.
- FastScan
- Flag to increase speed of extracting information from JPEG images. 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 with RIFF-format files (AVI,
WAV, etc), so any trailing metadata (eg. XMP written by some utilities)
may be missed. 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. Default is 0.
- 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.
- 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, the coordinates of the nearest fix are taken.
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.
- GoNoInterpolate
- Disable interpolation for geotagging. With this flag set to 1, geotagging
uses the nearest fix instead of interpolating between fixes. Default is
0.
- 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.pl), with a leading '-' for negative shifts.
Default is undef.
- 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.
- 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.
- 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.
- 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.
Default is 0.
- List
- Flag to extract lists of PrintConv values into arrays instead of joining
them into a string of values. The "ListSep" option specifies the
separator used when combining values. Default is 0.
- 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.
- ListSep
- Separator string used to join lists of PrintConv values when
"List" option is not set. 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.)
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 (default)
1 - Extract and rebuild maker notes into self-contained block
2 - Extract without rebuilding maker notes
- MissingTagValue
- Value for missing tags in expressions evaluated by
"SetNewValuesFromFile". If not set, a minor error is issued for
missing values, or the value is set to '' if "IgnoreMinorErrors"
is set. 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.
- PNGEarlyXMP
- Flag to write XMP in PNG images before the IDAT (image data) chunk. By
default, ExifTool adds new XMP to the end of a PNG file (just before
IEND). This is allowed by the PNG and XMP specifications, but some
utilities seem to ignore XMP if it comes after the image data. The
PNGEarlyXMP option causes ExifTool to instead add new XMP before the PNG
IDAT chunk. However, since ExifTool uses a single-pass writing algorithm,
it has no way to tell if XMP already exists later in the file before
writing the new XMP in this location. If this happens, a minor error is
issued when the extra XMP is encountered, and the file is not written.
Adding the "IgnoreMinorErrors" option causes the XMP after IDAT
to be deleted, thus resolving the conflict (at the expense of possible
metadata loss), and allowing the file to be written. The PNGEarlyXMP
option is applied automatically when deleting all XMP and writing new XMP
back in one step. When reading, this option causes a warning to be issued
if standard XMP is found after the IDAT chunk.
- PrintConv
- Flag to enable automatic print conversion. Also enables inverse print
conversion for writing. Default is 1.
- QuickTimeUTC
- Flag set to assume that QuickTime date/time values are stored as UTC,
causing conversion to local time when they are extracted. 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 0.
- 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). Note that this flag is
set automatically during a call to "SetNewValuesFromFile" to
make all tags available for copying. Default is 0.
- 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
0.
- 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.
- 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. Possible values are:
undef - 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
- TextOut
- Output file reference for Verbose and HtmlDump options. Default is
\*STDOUT.
- 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.
- 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.
- 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).
- 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)
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, CharsetID3, CharsetIPTC, CharsetPhotoshop,
CharsetQuickTime, Composite, ExtractEmbedded, FastScan, FixBase, HtmlDump,
HtmlDumpBase, IgnoreMinorErrors, Lang, LargeFileSupport, MakerNotes,
PNGEarlyXMP, ScanForXMP, Struct, TextOut, Unknown and Verbose.
- 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, Group#,
GlobalTimeShift, Lang, List, ListSep, PrintConv, Sort (if a tag list
reference is given) and StrictDate.
- Return Value:
- Reference to information hash, the same as with
"ImageInfo".
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.
# 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, 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, 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, CharsetIPTC, Compact, Compress, FixBase,
IgnoreMinorErrors, PNGEarlyXMP and Verbose.
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.
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.
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, or the original raw (Raw) value. 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 List 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, GlobalTimeShift, Lang, List, ListSep,
PrintConv and StrictDate.
- Inputs:
- 0) ExifTool object reference
1) Tag key
2) [optional] Value type: 'PrintConv', 'ValueConv', 'Both', 'Raw' 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. '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 values and
the List option is disabled 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. 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.
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);
# 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 <
http://owl.phy.queensu.ca/~phil/exiftool/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 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. 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. 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. 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 previous new values for this tag and replace
with the specified new value) or 2 (reset previous new values only).
- 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.pl 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 as in the
last example above 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, Escape, IgnoreMinorErrors, Lang, ListSep, ListSplit, PrintConv, Verbose
and WriteMode.
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, 'IPTC:Keywords>XMP-dc:Subject');
# add all IPTC keywords to XMP subject list
$exifTool->SetNewValuesFromFile($fp, 'IPTC:Keywords+>XMP-dc:Subject');
# 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 or 2 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). 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 an expression containing tag names with
leading '$' symbols (eg. 'Comment<the file is $filename'). Braces '{}'
may be used around the 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 Perl expressions placed inside the braces and after a semicolon
following the tag name. 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".
- 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.
GetNewValues¶
Get list of new Raw values for the specified tag. These are the values that will
be written to file. Most tags return only a single value, but List-type tags
may return multiple values.
$rawVal = $exifTool->GetNewValues($tag);
@rawVals = $exifTool->GetNewValues($tag);
- Inputs:
- 0) ExifTool object reference
1) Tag name (case sensitive, may be prefixed by family 0 or 1 group
name)
- 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).
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.
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, and requires Win32API::File::Time to be installed.
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 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] 'Link' to create a hard 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 if the file name or directory was changed, 0 if nothing was done, or -1
if there was an error renaming the file.
- Notes:
- Will not overwrite existing files. New directories are created as
necessary.
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 then XMP. 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...)
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.)
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 have
family 4 group names of 'Copy1', 'Copy2', 'Copy3', etc.
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.
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, so 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. However
if you enable the Composite option, "BuildCompositeTags" is
called from within "ImageInfo" before the file is closed.
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).
Get list of all available tag names.
@tagList = Image::ExifTool::GetAllTags($group);
- Inputs:
- 0) [optional] Group name, or string of group names separated by
colons
- Return Values:
- A list of all available tags in alphabetical order, or all tags in a
specified group or intersection of groups. The group name is case
insensitive, and any group in families 0-2 may be used except for EXIF
family 1 groups (ie. the specific IFD).
Get list of all writable tag names.
@tagList = Image::ExifTool::GetWritableTags($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 (0-4)
- 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):
- AFCP, AIFF, APE, APP0, APP1, APP11, APP12, APP13, APP14, APP15, APP4,
APP5, APP6, APP8, ASF, CanonVRD, Composite, DICOM, DNG, DV, DjVu, Ducky,
EXE, EXIF, ExifTool, FLAC, FLIR, File, Flash, FlashPix, Font, FotoStation,
GIF, GIMP, GeoTiff, H264, HTML, ICC_Profile, ID3, IPTC, ITC, JFIF, JPEG,
Jpeg2000, LNK, Leaf, Lytro, M2TS, MIE, MIFF, MNG, MPC, MPEG, MPF, MXF,
MakerNotes, Matroska, Meta, Ogg, OpenEXR, PDF, PICT, PLIST, PNG, PSP,
Palm, PanasonicRaw, PhotoCD, PhotoMechanic, Photoshop, PostScript,
PrintIM, QuickTime, RAF, RIFF, RSRC, RTF, Radiance, Rawzor, Real, SVG,
SigmaRaw, Stim, Theora, Torrent, Vorbis, XML, XMP, ZIP
- Family 1 (Specific Location):
- AC3, AFCP, AIFF, APE, ASF, AVI1, Adobe, AdobeCM, AdobeDNG, Apple, CIFF,
Canon, CanonCustom, CanonRaw, CanonVRD, Casio, Chapter#, Composite, DICOM,
DNG, DV, DjVu, DjVu-Meta, Ducky, EPPIM, EXE, EXIF, ExifIFD, ExifTool,
FLAC, FLIR, File, Flash, FlashPix, Font, FotoStation, FujiFilm, FujiIFD,
GE, GIF, GIMP, GPS, GeoTiff, GlobParamIFD, GraphConv, H264, HP, HTC, HTML,
HTML-dc, HTML-ncc, HTML-office, HTML-prod, HTML-vw96, HTTP-equiv,
ICC-chrm, 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#, ITC, InteropIFD, JFIF, JPEG, JPEG-HDR, JVC, Jpeg2000,
KDC_IFD, Kodak, KodakBordersIFD, KodakEffectsIFD, KodakIFD, KyoceraRaw,
LNK, Leaf, LeafSubIFD, Leica, Lytro, 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, MNG, MOBI, MPC,
MPEG, MPF0, MPImage, MXF, MakerNotes, MakerUnknown, Matroska,
MediaJukebox, MetaIFD, Microsoft, Minolta, MinoltaRaw, NITF, Nikon,
NikonCapture, NikonCustom, NikonScan, Nintendo, Ocad, Ogg, Olympus,
OpenEXR, PDF, PICT, PNG, PNG-pHYs, PSP, Palm, Panasonic, PanasonicRaw,
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,
Ricoh, SPIFF, SR2, SR2DataIFD, SR2SubIFD, SRF#, SVG, Samsung, Sanyo,
Scalado, Sigma, SigmaRaw, Sony, SonyIDC, Stim, SubIFD, System, Theora,
Torrent, Track#, Version0, Vorbis, XML, XMP, XMP-DICOM, XMP-GPano, XMP-MP,
XMP-MP1, XMP-PixelLive, XMP-aas, XMP-acdsee, XMP-album, XMP-apple-fi,
XMP-aux, XMP-cc, XMP-cell, XMP-crs, XMP-dc, XMP-dex, XMP-digiKam, XMP-dwc,
XMP-exif, XMP-exifEX, XMP-expressionmedia, XMP-extensis, XMP-fpv,
XMP-getty, XMP-ics, XMP-iptcCore, XMP-iptcExt, XMP-lr, XMP-mediapro,
XMP-microsoft, XMP-mwg-coll, XMP-mwg-kw, XMP-mwg-rs, XMP-pdf, XMP-pdfx,
XMP-photomech, XMP-photoshop, XMP-plus, XMP-prism, XMP-prl, XMP-pur,
XMP-rdf, XMP-swf, XMP-tiff, XMP-x, XMP-xmp, XMP-xmpBJ, XMP-xmpDM,
XMP-xmpMM, XMP-xmpNote, XMP-xmpPLUS, XMP-xmpRights, XMP-xmpTPg, ZIP
- Family 2 (Category):
- Audio, Author, Camera, Document, ExifTool, Image, Location, Other,
Printing, Time, Unknown, Video
- Family 3 (Document Number):
- Doc#, Main
- Family 4 (Instance Number):
- Copy#
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:
AFCP, APP0, APP1, APP10, APP11, APP12, APP13, APP14, APP15, APP2, APP3,
APP4, APP5, APP6, APP7, APP8, APP9, Adobe, CIFF, CanonVRD, Ducky, EXIF,
ExifIFD, File, FlashPix, FotoStation, GPS, GlobParamIFD, ICC_Profile,
IFD0, IFD1, IPTC, InteropIFD, JFIF, Jpeg2000, MIE, MPF, MakerNotes, Meta,
MetaIFD, NikonCapture, PDF, PDF-update, PNG, PhotoMechanic, Photoshop,
PrintIM, RMETA, RSRC, SubIFD, Trailer, XML, XML-*, XMP, XMP-*
All names in this list are either family 0 or family 1 group names, with the
exception of 'Trailer' which allows all trailers in JPEG and TIFF-format
images to be deleted at once, including unknown trailers. To schedule a
group for deletion, call "SetNewValue" with an undefined value
and a tag name like 'Trailer:*'.
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. Set to 0 to
return type for recognized but unsupported files (otherwise the return
value for unsupported files is undef).
- 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 array 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, EXV and EXIF
files.
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 the 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.
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 Set:
- The encoding for strings passed to/from ExifTool API functions. This is
set via the "Charset" option, which is 'UTF8' by default.
- 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" and "CharsetQuickTime"
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 a 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.
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
"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.
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 2003-2014, 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.pl,
Image::Info(3pm),
Image::MetaData::JPEG(3pm)