envato / exiv2

A simple wrapper around exiv2
MIT License
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Exiv2

License MIT Gem Version Gem Downloads Build Status

A simple wrapper around the C++ Exiv2 libary for reading and writing image metadata.

See http://www.exiv2.org/

Requires that the exiv2 C++ library is installed.

Usage

gem install exiv2

If you are on new version of Command Line Tool (that is newer than 6.2, and bump into following error:

/Library/Developer/CommandLineTools/usr/bin/../include/c++/v1/iterator:341:10: fatal error: '__debug' file not found
#include <__debug>

You can follow the quick hack by touching a new file /Library/Developer/CommandLineTools/usr/include/c++/v1/__debug with content:

#ifndef _LIBCPP_ASSERT
#define _LIBCPP_ASSERT(...) ((void)0)
#endif

Once everything is successfully installed, you can give it a go:

require 'exiv2'
image = Exiv2::ImageFactory.open("image.jpg")
image.read_metadata
image.iptc_data.each do |key, value|
  puts "#{key} = #{value}\n"
end
image.exif_data.each { ... }
image.xmp_data.each { ... }

iptc_data_hash  = image.iptc_data.to_hash
xmp_data_hash   = image.xmp_data.to_hash

image.exif_data.delete("Exif.Image.Software")
image.iptc_data.delete_all("Iptc.Application2.Keywords")

image.iptc_data["Iptc.Application2.Caption"] = "A New Caption"
image.iptc_data.add("Iptc.Application2.Keywords", "fishy")

image.write_metadata

Why?

None of the existing Ruby libraries for reading and writing image metadata did quite what we wanted, so we figured it wouldn't be too hard to wrap enough of Exiv2 to meet our needs.

The intention is to just mirror the Exiv2 API in Ruby, so the path to extending this to support more of Exiv2's functionality should be straightforward. Patches are welcome.

Compatibility

Tested on 2.6.x, 2.7.x, 3.0.x, 3.1.x and 3.2.x with Exiv2 0.27.1 and 0.28.0.

Developing

Status

In early development. Very little of Exiv2's API is supported, and it hasn't been heavily tested.

Contributors

Pete Yandell, Mark Turnley, Lucas Parry, Norbert Wojtwoicz, Jan Graichen, John Barton

Copyright

Copyright (c) 2014 Envato & Pete Yandell. See LICENSE for details.