Thin wrapper on top of libexiv2python.Preview, for a better encapsulation.

5 files changed, 95 insertions, 23 deletions

diff --git a/doc/api.rst b/doc/api.rst
index 9703fca..e373487 100644
--- a/doc/api.rst
+++ b/doc/api.rst
@@ -45,6 +45,13 @@ pyexiv2.xmp
 .. autoclass:: XmpTag
    :members: key, type, name, title, description, raw_value, value
 
+pyexiv2.preview
+###############
+
+.. module:: pyexiv2.preview
+.. autoclass:: Preview
+   :members: mime_type, extension, size, dimensions, data, write_to_file
+
 pyexiv2.utils
 #############
 
diff --git a/src/exiv2wrapper_python.cpp b/src/exiv2wrapper_python.cpp
index faa9b81..e5855c4 100644
--- a/src/exiv2wrapper_python.cpp
+++ b/src/exiv2wrapper_python.cpp
@@ -96,28 +96,15 @@ BOOST_PYTHON_MODULE(libexiv2python)
         .def("_getLangAltValue", &XmpTag::getLangAltValue)
     ;
 
-    class_<Preview>("Preview",
-                    "A preview image (properties and data buffer) embedded in "
-                    "image metadata.",
-                    init<Exiv2::PreviewImage>())
-
-        .def_readonly("mime_type", &Preview::_mimeType,
-                      "The mime type of the preview image (e.g. 'image/jpeg')")
-        .def_readonly("extension", &Preview::_extension,
-                      "The file extension of the preview image with a leading "
-                      "dot (e.g. '.jpg')")
-        .def_readonly("size", &Preview::_size,
-                      "The size of the preview image in bytes")
-        .def_readonly("dimensions", &Preview::_dimensions,
-                      "A tuple containing the width and height of the preview "
-                      "image in pixels")
-        .def_readonly("data", &Preview::_data,
-                      "The preview image data buffer")
-
-        .def("write_to_file", &Preview::writeToFile,
-             "Write the preview image to a file on disk.\n"
-             "The file extension will be automatically appended to the path\n"
-             "passed in parameter.")
+    class_<Preview>("_Preview", init<Exiv2::PreviewImage>())
+
+        .def_readonly("mime_type", &Preview::_mimeType)
+        .def_readonly("extension", &Preview::_extension)
+        .def_readonly("size", &Preview::_size)
+        .def_readonly("dimensions", &Preview::_dimensions)
+        .def_readonly("data", &Preview::_data)
+
+        .def("write_to_file", &Preview::writeToFile)
     ;
 
     class_<Image>("_Image", init<std::string>())
diff --git a/src/pyexiv2/__init__.py b/src/pyexiv2/__init__.py
index a1cc8da..2fbddc8 100644
--- a/src/pyexiv2/__init__.py
+++ b/src/pyexiv2/__init__.py
@@ -63,6 +63,7 @@ from pyexiv2.metadata import ImageMetadata
 from pyexiv2.exif import ExifValueError, ExifTag
 from pyexiv2.iptc import IptcValueError, IptcTag
 from pyexiv2.xmp import XmpValueError, XmpTag
+from pyexiv2.preview import Preview
 from pyexiv2.utils import FixedOffset, Rational, NotifyingList, \
                           undefined_to_string, string_to_undefined, \
                           GPSCoordinate
diff --git a/src/pyexiv2/metadata.py b/src/pyexiv2/metadata.py
index 5cbfeb5..c275a9d 100644
--- a/src/pyexiv2/metadata.py
+++ b/src/pyexiv2/metadata.py
@@ -37,6 +37,7 @@ import libexiv2python
 from pyexiv2.exif import ExifTag
 from pyexiv2.iptc import IptcTag
 from pyexiv2.xmp import XmpTag
+from pyexiv2.preview import Preview
 
 
 class ImageMetadata(object):
@@ -299,7 +300,7 @@ class ImageMetadata(object):
     def previews(self):
         """List of the previews available in the image, sorted by increasing
         size."""
-        return self._image._previews()
+        return [Preview(preview) for preview in self._image._previews()]
 
     def copy(self, other, exif=True, iptc=True, xmp=True):
         """
diff --git a/src/pyexiv2/preview.py b/src/pyexiv2/preview.py
new file mode 100644
index 0000000..a2b0ea1
--- /dev/null
+++ b/src/pyexiv2/preview.py
@@ -0,0 +1,76 @@
+# -*- coding: utf-8 -*-
+
+# ******************************************************************************
+#
+# Copyright (C) 2010 Olivier Tilloy <olivier@tilloy.net>
+#
+# This file is part of the pyexiv2 distribution.
+#
+# pyexiv2 is free software; you can redistribute it and/or
+# modify it under the terms of the GNU General Public License
+# as published by the Free Software Foundation; either version 2
+# of the License, or (at your option) any later version.
+#
+# pyexiv2 is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with pyexiv2; if not, write to the Free Software
+# Foundation, Inc., 51 Franklin Street, 5th Floor, Boston, MA 02110-1301 USA.
+#
+# Author: Olivier Tilloy <olivier@tilloy.net>
+#
+# ******************************************************************************
+
+"""
+Provide the Preview class.
+"""
+
+class Preview(object):
+
+    """
+    A preview image (properties and data buffer) embedded in image metadata.
+    """
+
+    def __init__(self, preview):
+        self.__preview = preview
+
+    @property
+    def mime_type(self):
+        """The mime type of the preview image (e.g. ``image/jpeg``)."""
+        return self.__preview.mime_type
+
+    @property
+    def extension(self):
+        """The file extension of the preview image with a leading dot
+        (e.g. ``.jpg``)."""
+        return self.__preview.extension
+
+    @property
+    def size(self):
+        """The size of the preview image in bytes."""
+        return self.__preview.size
+
+    @property
+    def dimensions(self):
+        """A tuple containing the width and height of the preview image
+        in pixels."""
+        return self.__preview.dimensions
+
+    @property
+    def data(self):
+        """The preview image data buffer."""
+        return self.__preview.data
+
+    def write_to_file(self, path):
+        """
+        Write the preview image to a file on disk.
+        The file extension will be automatically appended to the path.
+
+        :param path: path to write the preview to (without an extension)
+        :type path: string
+        """
+        return self.__preview.write_to_file(path)
+