Make imageio an optional dependency (pyvista#4333)

* Make imageio an optional dependency

* Run pre-commit

* make imageio optional in tests

* Apply suggestions from code review

* Update requirements_docs.txt

* Update pyproject.toml

* improve coverage

* hide try_imageio_imread

---------

Co-authored-by: Alex Kaszynski <[email protected]>
Co-authored-by: Tetsuo Koyama <[email protected]>

pyproject.toml

@@ -26,7 +26,6 @@ classifiers = [
     'Programming Language :: Python :: 3.11',
 ]
 dependencies = [
-    'imageio',
     'matplotlib>=3.0.1',
     'numpy',
     'pillow',
@@ -38,18 +37,29 @@ dynamic = ['version']
 
 [project.optional-dependencies]
 all = [
+    'imageio',
     'cmocean',
     'colorcet',
     'ipyvtklink',
+    'ipywidgets',
+    'jupyter-server-proxy',
     'meshio>=5.2',
+    'nest_asyncio',
     'panel',
     'pythreejs',
+    'trame-client>=2.4.2',
+    'trame-server>=2.8.0',
+    'trame-vtk>=2.4.0',
+    'trame>=2.2.6',
 ]
 colormaps = [
     'cmocean',
     'colorcet',
 ]
-io = ['meshio>=5.2']
+io = [
+    'imageio',
+    'meshio>=5.2'
+]
 jupyter = [
     'ipyvtklink',
     'ipywidgets',

pyvista/core/texture.py

@@ -9,7 +9,7 @@
 import pyvista as pv
 from pyvista import _vtk
 from pyvista.plotting.opts import AnnotatedIntEnum
-from pyvista.utilities.misc import PyVistaDeprecationWarning
+from pyvista.utilities.misc import PyVistaDeprecationWarning, _try_imageio_imread
 
 from .dataset import DataObject
 
@@ -148,10 +148,8 @@ def _from_file(self, filename, **kwargs):
             if image.n_points < 2:
                 raise RuntimeError("Problem reading the image with VTK.")  # pragma: no cover
             self._from_image_data(image)
-        except (KeyError, ValueError):
-            from imageio import imread
-
-            self._from_array(imread(filename))
+        except (KeyError, ValueError, OSError):
+            self._from_array(_try_imageio_imread(filename))  # pragma: no cover
 
     def _from_texture(self, texture):
         image = texture.GetInput()

pyvista/plotting/plotting.py

@@ -4811,6 +4811,8 @@ def add_text(
     def open_movie(self, filename, framerate=24, quality=5, **kwargs):
         """Establish a connection to the ffmpeg writer.
 
+        Requires ``imageio`` to be installed.
+
         Parameters
         ----------
         filename : str
@@ -4842,7 +4844,12 @@ def open_movie(self, filename, framerate=24, quality=5, **kwargs):
         >>> pl.open_movie('movie.mp4', quality=10)  # doctest:+SKIP
 
         """
-        from imageio import get_writer
+        try:
+            from imageio import get_writer
+        except ModuleNotFoundError:  # pragma: no cover
+            raise ModuleNotFoundError(
+                'Install imageio to use `open_movie` with:\n\n   pip install imageio'
+            ) from None
 
         if isinstance(pyvista.FIGURE_PATH, str) and not os.path.isabs(filename):
             filename = os.path.join(pyvista.FIGURE_PATH, filename)
@@ -4851,6 +4858,8 @@ def open_movie(self, filename, framerate=24, quality=5, **kwargs):
     def open_gif(self, filename, loop=0, fps=10, palettesize=256, subrectangles=False, **kwargs):
         """Open a gif file.
 
+        Requires ``imageio`` to be installed.
+
         Parameters
         ----------
         filename : str
@@ -4899,7 +4908,12 @@ def open_gif(self, filename, loop=0, fps=10, palettesize=256, subrectangles=Fals
         See :ref:`gif_movie_example` for a full example using this method.
 
         """
-        from imageio import get_writer
+        try:
+            from imageio import get_writer
+        except ModuleNotFoundError:  # pragma: no cover
+            raise ModuleNotFoundError(
+                'Install imageio to use `open_gif` with:\n\n   pip install imageio'
+            ) from None
 
         if filename[-3:] != 'gif':
             raise ValueError('Unsupported filetype.  Must end in .gif')

pyvista/utilities/errors.py

@@ -337,10 +337,11 @@ class Report(scooby.Report):
     def __init__(self, additional=None, ncol=3, text_width=80, sort=False, gpu=True):
         """Generate a :class:`scooby.Report` instance."""
         # Mandatory packages
-        core = ['pyvista', 'vtk', 'numpy', 'matplotlib', 'imageio', 'scooby', 'pooch']
+        core = ['pyvista', 'vtk', 'numpy', 'matplotlib', 'scooby', 'pooch']
 
         # Optional packages.
         optional = [
+            'imageio',
             'pyvistaqt',
             'PyQt5',
             'IPython',

pyvista/utilities/fileio.py

@@ -8,7 +8,7 @@
 
 import pyvista
 from pyvista import _vtk
-from pyvista.utilities.misc import PyVistaDeprecationWarning
+from pyvista.utilities.misc import PyVistaDeprecationWarning, _try_imageio_imread
 
 
 def _get_ext_force(filename, force_ext=None):
@@ -232,6 +232,9 @@ def _apply_attrs_to_reader(reader, attrs):
 def read_texture(filename, attrs=None, progress_bar=False):
     """Load a texture from an image file.
 
+    Will attempt to read any file type supported by ``vtk``, however
+    if it fails, it will attempt to use ``imageio`` to read the file.
+
     Parameters
     ----------
     filename : str
@@ -276,9 +279,8 @@ def read_texture(filename, attrs=None, progress_bar=False):
     except (KeyError, ValueError):
         # Otherwise, use the imageio reader
         pass
-    import imageio
 
-    return pyvista.Texture(imageio.imread(filename))
+    return pyvista.Texture(_try_imageio_imread(filename))  # pragma: no cover
 
 
 def read_exodus(

pyvista/utilities/misc.py

@@ -35,6 +35,38 @@ def _check_range(value, rng, parm_name):
         )
 
 
+def _try_imageio_imread(filename):
+    """Attempt to read a file using ``imageio.imread``.
+
+    Parameters
+    ----------
+    filename : str
+        Name of the file to read using ``imageio``.
+
+    Returns
+    -------
+    imageio.core.util.Array
+        Image read from ``imageio``.
+
+    Raises
+    ------
+    ModuleNotFoundError
+        Raised when ``imageio`` is not installed when attempting to read
+        ``filename``.
+
+    """
+    try:
+        from imageio import imread
+    except ModuleNotFoundError:  # pragma: no cover
+        raise ModuleNotFoundError(
+            'Problem reading the image with VTK. Install imageio to try to read the '
+            'file using imageio with:\n\n'
+            '   pip install imageio'
+        ) from None
+
+    return imread(filename)
+
+
 @lru_cache(maxsize=None)
 def has_module(module_name):
     """Return if a module can be imported."""

requirements.txt

@@ -4,7 +4,6 @@
 #  This is to prevent installing `vtk` from PyPI
 #  when using a custom variant like `vtk_osmesa`
 #  which we do in some of our CI jobs.
-imageio<2.28.0
 matplotlib<3.7.2
 numpy<1.25.0
 pillow<9.6.0

requirements_docs.txt

@@ -2,6 +2,7 @@
 cmocean==3.0.3
 colorcet==3.0.1
 enum-tools==0.9.0.post1
+imageio==2.27.0
 imageio-ffmpeg==0.4.8
 ipygany==0.5.0
 ipyvtklink==0.2.3

requirements_test.txt

@@ -4,6 +4,7 @@
 cmocean<3.1
 colorcet<3.1.0
 hypothesis<6.74.1
+imageio<2.28.0
 imageio-ffmpeg<0.5.0
 ipygany<0.6.0
 ipython<9.0.0

tests/plotting/test_plotting.py

@@ -12,7 +12,6 @@
 import time
 
 from PIL import Image
-import imageio
 import matplotlib
 import numpy as np
 import pytest
@@ -33,18 +32,28 @@
 if not system_supports_plotting():
     pytestmark = pytest.mark.skip(reason='Requires system to support plotting')
 
+HAS_IMAGEIO = True
+try:
+    import imageio
+except ModuleNotFoundError:
+    HAS_IMAGEIO = False
+
 
 ffmpeg_failed = False
 try:
     try:
         import imageio_ffmpeg
 
         imageio_ffmpeg.get_ffmpeg_exe()
-    except ImportError:
-        imageio.plugins.ffmpeg.download()
+    except ImportError as err:
+        if HAS_IMAGEIO:
+            imageio.plugins.ffmpeg.download()
+        else:
+            raise err
 except:  # noqa: E722
     ffmpeg_failed = True
 
+
 THIS_PATH = pathlib.Path(__file__).parent.absolute()
 
 
@@ -763,13 +772,15 @@ def test_add_lines_invalid():
         plotter.add_lines(range(10))
 
 
+@pytest.mark.skipif(not HAS_IMAGEIO, reason="Requires imageio")
 def test_open_gif_invalid():
     plotter = pyvista.Plotter()
     with pytest.raises(ValueError):
         plotter.open_gif('file.abs')
 
 
 @pytest.mark.skipif(ffmpeg_failed, reason="Requires imageio-ffmpeg")
+@pytest.mark.skipif(not HAS_IMAGEIO, reason="Requires imageio")
 def test_make_movie(sphere, tmpdir, verify_image_cache):
     verify_image_cache.skip = True
 
@@ -1228,6 +1239,7 @@ def test_plot_texture_associated():
     plotter.show()
 
 
+@pytest.mark.skipif(not HAS_IMAGEIO, reason="Requires imageio")
 def test_read_texture_from_numpy():
     """Test adding a texture to a plot"""
     globe = examples.load_globe()
@@ -2509,6 +2521,7 @@ def test_pointset_plot_as_points_vtk():
     pl.show()
 
 
+@pytest.mark.skipif(not HAS_IMAGEIO, reason="Requires imageio")
 def test_write_gif(sphere, tmpdir):
     basename = 'write_gif.gif'
     path = str(tmpdir.join(basename))

tests/utilities/test_misc.py

@@ -2,7 +2,14 @@
 
 import pytest
 
-from pyvista.utilities.misc import _set_plot_theme_from_env, has_module
+from pyvista import examples
+from pyvista.utilities.misc import _set_plot_theme_from_env, _try_imageio_imread, has_module
+
+HAS_IMAGEIO = True
+try:
+    import imageio
+except ModuleNotFoundError:
+    HAS_IMAGEIO = False
 
 
 def test_set_plot_theme_from_env():
@@ -17,3 +24,9 @@ def test_set_plot_theme_from_env():
 def test_has_module():
     assert has_module('pytest')
     assert not has_module('not_a_module')
+
+
+@pytest.mark.skipif(not HAS_IMAGEIO, reason="Requires imageio")
+def test_try_imageio_imread():
+    img = _try_imageio_imread(examples.mapfile)
+    assert isinstance(img, imageio.core.util.Array)

tests/utilities/test_reader.py

@@ -9,6 +9,13 @@
 from pyvista import examples
 from pyvista.examples.downloads import download_file
 
+HAS_IMAGEIO = True
+try:
+    import imageio  # noqa: F401
+except ModuleNotFoundError:
+    HAS_IMAGEIO = False
+
+
 pytestmark = pytest.mark.skipif(
     platform.system() == 'Darwin', reason='MacOS testing on Azure fails when downloading'
 )
@@ -924,6 +931,7 @@ def test_hdf_reader():
     assert mesh.n_cells == 4800
 
 
+@pytest.mark.skipif(not HAS_IMAGEIO, reason="Requires imageio")
 def test_gif_reader(gif_file):
     reader = pyvista.get_reader(gif_file)
     assert isinstance(reader, pyvista.GIFReader)