exif(n) 1.1 exif "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.