exif

exif is a BSD licensed binding to the libexif library. Please note that while this egg is BSD licensed the libexif lib is distributed under the LGPL.

Currently only read support is implemented in this binding.

Usage

(require-extension exif)

Documentation

tag-alist-from-file

[procedure] (tag-alist-from-file FILENAME #!optional TAGLIST)

Reads in the EXIF data from the file defined by the FILENAME string and returns the values of the tags in TAGLIST as associated list. If TAGLIST is omitted a list of all known tags will be returned. Nonexistent tags will have #f as return value.

thumbnail->u8vector

[procedure] (thumbnail->u8vector FILENAME)

Reads the thumbnail from FILENAME and returns it as u8vector or #f if there isn't one.

Example

#;1> (tag-alist-from-file "img_3942.jpg" '(model make date-time))
((model . "Canon PowerShot G10") (make . "Canon") (date-time . "2010:08:20 20:38:18"))
#;2> (thumbnail->u8vector "img_3942.jpg")
#u8(255 216 255 219 0 132 0 9 6 6 8 6 5 9 ...

Author

Christian Kellermann

Repository

This egg is hosted on the CHICKEN Subversion repository:

https://anonymous@code.call-cc.org/svn/chicken-eggs/release/5/exif

If you want to check out the source code repository of this egg and you are not familiar with Subversion, see this page.

License

Copyright 2011 Christian Kellermann <ckeen@pestilenz.org>. All
rights reserved.

Redistribution and use in source and binary forms, with or without
modification, are permitted provided that the following conditions
are met:
   1. Redistributions of source code must retain the above
   copyright notice, this list of conditions and the following
   disclaimer.
   2. Redistributions in binary form must reproduce the above
   copyright notice, this list of conditions and the following
   disclaimer in the documentation and/or other materials provided
   with the distribution.
THIS SOFTWARE IS PROVIDED BY CHRISTIAN KELLERMANN ``AS IS'' AND ANY
EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL CHRISTIAN KELLERMANN OR
CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
SUCH DAMAGE.
The views and conclusions contained in the software and
documentation are those of the authors and should not be
interpreted as representing official policies, either expressed or
implied, of Christian Kellermann.

Version History

0.1: initial release
0.2: bugfix release
0.3: replace obsoleted null-pointer? predicate, no functionality changes
0.5: Add appropriate guard for the null-pointer? predicate
0.6: Return a list of all known tags when none are given
0.7: Correctly ref/unref entries, fixes a double free error found by mario-goulart
1.0: Chicken 5 release thanks to mario-goulart
1.1: Use pkg-config on non-windows systems only, thanks gahr!
1.2: Use external build script to invoke pkg-config

Introduction