NAME¶
tiff - TIFF reading, writing, and querying and manipulation of meta data
SYNOPSIS¶
package require
Tcl 8.2
package require
tiff ?0.2.1?
::tiff::isTIFF file
::tiff::byteOrder file
::tiff::numImages file
::tiff::dimensions file ?image?
::tiff::imageInfo file ?image?
::tiff::entries file ?image?
::tiff::getEntry file entry ?image?
::tiff::addEntry file entry ?image?
::tiff::deleteEntry file entry ?image?
::tiff::getImage file ?image?
::tiff::writeImage image file ?entry?
::tiff::nametotag names
::tiff::tagtoname tags
::tiff::debug file
DESCRIPTION¶
This package provides commands to query, modify, read, and write TIFF images.
TIFF stands for
Tagged Image File Format and is a standard for lossless
storage of photographical images and associated metadata. It is specified at
http://partners.adobe.com/public/developer/tiff/index.html.
Multiple images may be stored in a single TIFF file. The ?image? options to the
functions in this package are for accessing images other than the first. Data
in a TIFF image is stored as a series of tags having a numerical value, which
are represented in either a 4 digit hexadecimal format or a string name. For a
reference on defined tags and their meanings see
http://www.awaresystems.be/imaging/tiff/tifftags.html
COMMANDS¶
- ::tiff::isTIFF file
- Returns a boolean value indicating if file is a TIFF
image.
- ::tiff::byteOrder file
- Returns either big or little. Throws an error
if file is not a TIFF image.
- ::tiff::numImages file
- Returns the number of images in file. Throws an
error if file is not a TIFF image.
- ::tiff::dimensions file ?image?
- Returns the dimensions of image number ?image? in
file as a list of the horizontal and vertical pixel count. Throws
an error if file is not a TIFF image.
- ::tiff::imageInfo file ?image?
- Returns a dictionary with keys ImageWidth,
ImageLength, BitsPerSample, Compression,
PhotometricInterpretation, ImageDescription,
Orientation, XResolution, YResolution,
ResolutionUnit, DateTime, Artist, and
HostComputer. The values are the associated properties of the TIFF
?image? in file. Values may be empty if the associated tag is not
present in the file.
puts [::tiff::imageInfo photo.tif]
ImageWidth 686 ImageLength 1024 BitsPerSample {8 8 8} Compression 1
PhotometricInterpretation 2 ImageDescription {} Orientation 1
XResolution 170.667 YResolution 170.667 ResolutionUnit 2 DateTime {2005:12:28 19:44:45}
Artist {} HostComputer {}
- There is nothing special about these tags, this is simply a
convience procedure which calls getEntry with common entries.
Throws an error if file is not a TIFF image.
- ::tiff::entries file ?image?
- Returns a list of all entries in the given file and
?image? in hexadecimal format. Throws an error if file is not a
TIFF image.
- ::tiff::getEntry file entry
?image?
- Returns the value of entry from image ?image? in the
TIFF file. entry may be a list of multiple entries. If an
entry does not exist, an empty string is returned
set data [::tiff::getEntry photo.tif {0131 0132}]
puts "file was written at [lindex $data 0] with software [lindex $data 1]"
- Throws an error if file is not a TIFF image.
- ::tiff::addEntry file entry
?image?
- Adds the specified entries to the image named by ?image?
(default 0), or optionally all. entry must be a list where
each element is a list of tag, type, and value. If a tag already exists,
it is overwritten.
::tiff::addEntry photo.tif {{010e 2 "an example photo"} {013b 2 "Aaron F"}}
- The data types are defined as follows
- 1
- BYTE (8 bit unsigned integer)
- 2
- ASCII
- 3
- SHORT (16 bit unsigned integer)
- 4
- LONG (32 bit unsigned integer)
- 5
- RATIONAL
- 6
- SBYTE (8 bit signed byte)
- 7
- UNDEFINED (uninterpreted binary data)
- 8
- SSHORT (signed 16 bit integer)
- 9
- SLONG (signed 32 bit integer)
- 10
- SRATIONAL
- 11
- FLOAT (32 bit floating point number)
- 12
- DOUBLE (64 bit floating point number)
- Throws an error if file is not a TIFF image.
- ::tiff::deleteEntry file entry
?image?
- Deletes the specified entries from the image named by
?image? (default 0), or optionally all. Throws an error if
file is not a TIFF image.
- ::tiff::getImage file ?image?
- Returns the name of a Tk image containing the image at
index ?image? from file Throws an error if file is not a
TIFF image, or if image is an unsupported format. Supported formats are
uncompressed 24 bit RGB and uncompressed 8 bit palette.
- ::tiff::writeImage image file
?entry?
- Writes the contents of the Tk image image to a tiff
file file. Files are written in the 24 bit uncompressed format,
with big endian byte order. Additional entries to be added to the image
may be specified, in the same format as tiff::addEntry
- ::tiff::nametotag names
- Returns a list with names translated from string to
4 digit format. 4 digit names in the input are passed through unchanged.
Strings without a defined tag name will throw an error.
- ::tiff::tagtoname tags
- Returns a list with tags translated from 4 digit to
string format. If a tag does not have a defined name it is passed through
unchanged.
- ::tiff::debug file
- Prints everything we know about the given file in a nice
format.
VARIABLES¶
The mapping of 4 digit tag names to string names uses the array
::tiff::tiff_tags. The reverse mapping uses the array ::tiff::tiff_sgat.
LIMITATIONS¶
- [1]
- Cannot write exif ifd
- [2]
- Reading limited to uncompressed 8 bit rgb and 8 bit
palletized images
- [3]
- Writing limited to uncompressed 8 bit rgb
BUGS, IDEAS, FEEDBACK¶
This document, and the package it describes, will undoubtedly contain bugs and
other problems. Please report such in the category
tiff of the
Tcllib SF Trackers [
http://sourceforge.net/tracker/?group_id=12883].
Please also report any ideas for enhancements you may have for either package
and/or documentation.
KEYWORDS¶
image, tif, tiff
CATEGORY¶
File formats
COPYRIGHT¶
Copyright (c) 2005-2006, Aaron Faupell <afaupell@users.sourceforge.net>
