Copy image file model, views, and tests

Author: siddhantwahal

stage3.0_first_views/pycasa/model/image_file.py

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+# General imports
+import PIL.Image
+from PIL.ExifTags import TAGS
+import numpy as np
+
+# ETS imports
+from traits.api import cached_property, Dict, File, HasStrictTraits, Property
+
+
+class ImageFile(HasStrictTraits):
+    """ Model to hold an image file.
+    """
+    filepath = File
+
+    metadata = Property(Dict, depends_on="filepath")
+
+    def to_array(self):
+        if not self.filepath:
+            return np.array([])
+
+        with PIL.Image.open(self.filepath) as img:
+            return np.asarray(img)
+
+    @cached_property
+    def _get_metadata(self):
+        if not self.filepath:
+            return {}
+
+        with PIL.Image.open(self.filepath) as img:
+            exif = img._getexif()
+
+        if exif:
+            return {TAGS[k]: v for k, v in exif.items()
+                    if k in TAGS}
+        else:
+            return {}

stage3.0_first_views/pycasa/model/test_image_folder.py

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+from os.path import dirname, join, split
+import unittest
+
+from image_folder import ImageFolder
+
+import ets_tutorial
+
+TUTORIAL_DIR = dirname(ets_tutorial.__file__)
+SAMPLE_IMG_DIR = join(TUTORIAL_DIR, "..", "sample_images")
+
+
+class TestImageFolder(unittest.TestCase):
+    def test_filters_images(self):
+        img_folder = ImageFolder(directory=SAMPLE_IMG_DIR)
+        self.assertEqual(
+            sorted([split(img.filepath)[1] for img in img_folder.images]),
+            sorted(["IMG-0311_xmas_2020.JPG", "owls.jpg"])
+        )

stage3.0_first_views/pycasa/ui/image_file_view.py

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+# General imports
+from matplotlib.figure import Figure
+
+# ETS imports
+from traits.api import Instance, observe
+from traitsui.api import Item, ModelView, View
+
+# Local imports
+from ets_tutorial.util.mpl_figure_editor import MplFigureEditor
+from pycasa.model.image_file import ImageFile
+
+
+class ImageFileView(ModelView):
+    """ ModelView for an image file object.
+    """
+    model = Instance(ImageFile)
+
+    figure = Instance(Figure)
+
+    view = View(
+        Item("model.filepath", style="readonly", show_label=False),
+        Item("figure", editor=MplFigureEditor(), show_label=False)
+    )
+
+    @observe("model.filepath")
+    def build_mpl_figure(self, event):
+        figure = Figure()
+        axes = figure.add_subplot(111)
+        axes.imshow(self.model.to_array())
+        self.figure = figure
+
+
+if __name__ == '__main__':
+    from os.path import dirname, join
+    import ets_tutorial
+
+    TUTORIAL_DIR = dirname(ets_tutorial.__file__)
+    SAMPLE_IMG_DIR = join(TUTORIAL_DIR, "..", "sample_images")
+    SAMPLE_IMG1 = join(SAMPLE_IMG_DIR, "IMG-0311_xmas_2020.JPG")
+
+    image_file = ImageFile(filepath=SAMPLE_IMG1)
+    view = ImageFileView(model=image_file)
+    view.configure_traits()