Button to export Cubeviz movie

CHANGES.rst

@@ -14,6 +14,9 @@ New Features
 Cubeviz
 ^^^^^^^
 
+- Added the ability to export cube slices to video. User will need to install
+  ``opencv-python`` separately or use ``[all]`` specifier when installing Jdaviz. [#2264]
+
 Imviz
 ^^^^^
 
@@ -77,6 +80,9 @@ Bug Fixes
 Cubeviz
 ^^^^^^^
 
+- Moment Map plugin now writes FITS file to working directory if no path provided
+  in standalone mode. [#2264]
+
 Imviz
 ^^^^^
 

docs/cubeviz/plugins.rst

@@ -274,3 +274,28 @@ Export Plot
 ===========
 
 This plugin allows exporting the plot in a given viewer to various image formats.
+
+.. _cubeviz-export-video:
+
+Movie
+-----
+
+.. note::
+
+    For MPEG-4, this feature needs ``opencv-python`` to be installed;
+    see [opencv-python on PyPI](https://pypi.org/project/opencv-python/).
+
+Expand the "Export to video" section, then enter the desired starting and
+ending slice indices (inclusive), the frame rate in frames per second (FPS),
+and the filename.
+If a path is not given, the file will be saved to current working
+directory. Any existing file with the same name will be silently replaced.
+
+When you are ready, click the :guilabel:`Export to MP4` button.
+The movie will be recorded at the given FPS. While recording is in progress,
+it is highly recommended that you leave the app alone until it is done.
+
+While recording, there is an option to interrupt the recording when something
+goes wrong (e.g., it is taking too long or you realized you entered the wrong inputs).
+Click on the stop icon next to the :guilabel:`Export to MP4` button to interrupt it.
+Doing so will result in no output video.

jdaviz/configs/cubeviz/plugins/moment_maps/moment_maps.py

@@ -137,20 +137,29 @@ def _write_moment_to_fits(self, overwrite=False, *args):
         if self.moment is None or not self.filename:  # pragma: no cover
             return
 
-        path = Path(self.filename).resolve()
-        if path.exists():
+        # Make sure file does not end up in weird places in standalone mode.
+        path = os.path.dirname(self.filename)
+        if path and not os.path.exists(path):
+            raise ValueError(f"Invalid path={path}")
+        elif (not path or path.startswith("..")) and os.environ.get("JDAVIZ_START_DIR", ""):  # noqa: E501 # pragma: no cover
+            filename = Path(os.environ["JDAVIZ_START_DIR"]) / self.filename
+        else:
+            filename = Path(self.filename).resolve()
+
+        if filename.exists():
             if overwrite:
                 # Try to delete the file
-                path.unlink()
-                if path.exists():
+                filename.unlink()
+                if filename.exists():
                     # Warn the user if the file still exists
-                    raise FileExistsError(f"Unable to delete {path}. Check user permissions.")
+                    raise FileExistsError(f"Unable to delete {filename}. Check user permissions.")
             else:
                 self.overwrite_warn = True
                 return
 
-        self.moment.write(str(path))
+        filename = str(filename)
+        self.moment.write(filename)
 
         # Let the user know where we saved the file.
         self.hub.broadcast(SnackbarMessage(
-            f"Moment map saved to {os.path.abspath(self.filename)}", sender=self, color="success"))
+            f"Moment map saved to {os.path.abspath(filename)}", sender=self, color="success"))

jdaviz/configs/cubeviz/plugins/moment_maps/tests/test_moment_maps.py

@@ -131,3 +131,7 @@ def test_write_momentmap(cubeviz_helper, spectrum1d_cube, tmp_path):
         sky = w.pixel_to_world(0, 0)
         assert_allclose(sky.ra.deg, 204.9998877673)
         assert_allclose(sky.dec.deg, 27.0001)
+
+    plugin._obj.filename = "fake_path/test_file.fits"
+    with pytest.raises(ValueError, match="Invalid path"):
+        plugin._obj.vue_save_as_fits()

jdaviz/configs/cubeviz/plugins/slice/slice.py

@@ -122,7 +122,7 @@ def _watch_viewer(self, viewer, watch=True):
     def _on_data_added(self, msg):
         if isinstance(msg.viewer, BqplotImageView):
             if len(msg.data.shape) == 3:
-                self.max_value = msg.data.shape[-1] - 1
+                self.max_value = msg.data.shape[-1] - 1  # Same as i_end in Export Plot plugin
                 self._watch_viewer(msg.viewer, True)
                 msg.viewer.state.slices = (0, 0, int(self.slice))
 

jdaviz/configs/cubeviz/plugins/tests/test_export_plots.py

@@ -0,0 +1,93 @@
+import os
+
+import pytest
+
+from jdaviz.configs.default.plugins.export_plot.export_plot import HAS_OPENCV
+
+
+# TODO: Remove skip when https://github.com/bqplot/bqplot/pull/1397/files#r726500097 is resolved.
+@pytest.mark.skip(reason="Cannot test due to async JS callback")
+# @pytest.mark.skipif(not HAS_OPENCV, reason="opencv-python is not installed")
+def test_export_movie(cubeviz_helper, spectrum1d_cube, tmp_path):
+    orig_path = os.getcwd()
+    os.chdir(tmp_path)
+    try:
+        cubeviz_helper.load_data(spectrum1d_cube, data_label="test")
+        plugin = cubeviz_helper.plugins["Export Plot"]
+        assert plugin.i_start == 0
+        assert plugin.i_end == 1
+        assert plugin.movie_filename == "mymovie.mp4"
+
+        plugin._obj.vue_save_movie("mp4")
+        assert os.path.isfile("mymovie.mp4"), tmp_path
+    finally:
+        os.chdir(orig_path)
+
+
+@pytest.mark.skipif(HAS_OPENCV, reason="opencv-python is installed")
+def test_no_opencv(cubeviz_helper, spectrum1d_cube):
+    cubeviz_helper.load_data(spectrum1d_cube, data_label="test")
+    plugin = cubeviz_helper.plugins["Export Plot"]
+    assert plugin._obj.movie_msg != ""
+    with pytest.raises(ImportError, match="Please install opencv-python"):
+        plugin.save_movie()
+
+
+@pytest.mark.skipif(not HAS_OPENCV, reason="opencv-python is not installed")
+def test_export_movie_not_cubeviz(imviz_helper):
+    plugin = imviz_helper.plugins["Export Plot"]
+
+    with pytest.raises(NotImplementedError, match="save_movie is not available for config"):
+        plugin._obj.save_movie()
+
+    # Also not available via plugin public API.
+    with pytest.raises(AttributeError):
+        plugin.save_movie()
+
+
+@pytest.mark.skipif(not HAS_OPENCV, reason="opencv-python is not installed")
+def test_export_movie_cubeviz_exceptions(cubeviz_helper, spectrum1d_cube):
+    cubeviz_helper.load_data(spectrum1d_cube, data_label="test")
+    cubeviz_helper.default_viewer.shape = (100, 100)
+    cubeviz_helper.app.get_viewer("uncert-viewer").shape = (100, 100)
+    plugin = cubeviz_helper.plugins["Export Plot"]
+    assert plugin._obj.movie_msg == ""
+    assert plugin.i_start == 0
+    assert plugin.i_end == 1
+    assert plugin.movie_filename == "mymovie.mp4"
+
+    with pytest.raises(NotImplementedError, match="filetype"):
+        plugin.save_movie(filetype="gif")
+
+    with pytest.raises(NotImplementedError, match="filetype"):
+        plugin.save_movie(filename="mymovie.gif", filetype=None)
+
+    with pytest.raises(ValueError, match="No frames to write"):
+        plugin.save_movie(i_start=0, i_end=0)
+
+    with pytest.raises(ValueError, match="Invalid frame rate"):
+        plugin.save_movie(fps=0)
+
+    plugin.movie_filename = "fake_path/mymovie.mp4"
+    with pytest.raises(ValueError, match="Invalid path"):
+        plugin.save_movie()
+
+    plugin.movie_filename = "mymovie.mp4"
+    plugin.viewer = 'spectrum-viewer'
+    with pytest.raises(TypeError, match=r"Movie for.*is not supported"):
+        plugin.save_movie()
+
+    plugin.movie_filename = ""
+    plugin.viewer = 'uncert-viewer'
+    with pytest.raises(ValueError, match="Invalid filename"):
+        plugin.save_movie()
+
+
+@pytest.mark.skipif(not HAS_OPENCV, reason="opencv-python is not installed")
+def test_export_movie_cubeviz_empty(cubeviz_helper):
+    plugin = cubeviz_helper.plugins["Export Plot"]
+    assert plugin.i_start == 0
+    assert plugin.i_end == 0
+
+    with pytest.raises(ValueError, match="Selected viewer has no display shape"):
+        plugin.save_movie(i_start=0, i_end=1)