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exif(n) 1.1 "EXIF parsing"
exif - Tcl EXIF extracts and parses EXIF fields from digital
images
package require Tcl 8.2
package require exif ?1.1?
The EXIF package is a recoding of Chris Breeze's Perl package to
do the same thing. This version accepts a channel as input and
returns a serialized array with all the recognised fields parsed
out.
There is also a function to obtain a list of all possible field
names that might be present, which is useful in building GUIs that
present such information.
- exif::analyze channel ?thumbnail?
- channel should be an open file handle
rewound to the start. It does not need to be seekable. channel will be set to binary mode and is left wherever
it happens to stop being parsed, usually at the end of the file or
the start of the image data. You must open and close the stream
yourself. If no error is thrown, the return value is a serialized
array with informative English text about what was found in the
EXIF block. Failure during parsing or I/O throw errors.
If thumbnail is present and not the empty
string it will be interpreted as the name of a file, and the
thumbnail image contained in the exif data will be written into
it.
- exif::analyzeFile filename ?thumbnail?
- This is a file-based wrapper around exif::analyze. Instead of taking a stream it takes a filename and analyzes the contents of the specified
file.
- exif::fieldnames
- This returns a list of all possible field names. That is, the
array returned by exif::analyze will not contain
keys that are not listed in the return from exif::fieldnames. Of course, if information is missing in
the image file, exif::analyze may not return all
the fields listed in the return from exif::fieldnames. This
function is expected to be primarily useful for building GUIs to
display results.
N.B.: Read the implementation of exif::fieldnames before modifying the implementation of
exif::analyze.
(c) 2002 Darren New Hold harmless the author, and any lawful use
is allowed.
This code is a direct translation of version 1.3 of exif.pl by
Chris Breeze. See the source for full headers, references, etc.