[WIP] rework artists.stitch_to_animation

CHANGELOG.md

@@ -12,13 +12,15 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/).
 - new artist helper function: `norm_from_channel`
 - new artist helper function: `ticks_from_norm`
 - new artist iterator `ChopHandler`
+- `artists.stitch_to_animation`: new kwargs for more gif customization
 
 ### Fixed
 - fixed Quick2D/Quick1D issues where collapsing unused dims did not work
 - wt5 explore : fixed bug where data will not load interactively if directory is not cwd
 - constants in chopped data will inherit the units of the original data
 
 ## Changed
+- use `pillow` directly and remove `ImageIO` dependency
 - refactor of artists.quick1D and artists.quick2D
 - quick2D and quick1D will not force `autosave=True` if the number of figures is large.  Instead, interactive plotting will be truncated if the number of figures is large.
 - artists now gets turbo colormap straight from matplotlib

WrightTools/artists/_helpers.py

@@ -3,7 +3,7 @@
 # --- import --------------------------------------------------------------------------------------
 
 
-import os
+import pathlib
 
 import numpy as np
 
@@ -15,6 +15,7 @@
 
 from matplotlib.colors import Normalize, CenteredNorm, TwoSlopeNorm
 from mpl_toolkits.axes_grid1 import make_axes_locatable
+from typing import List
 
 import imageio.v3 as iio
 import warnings
@@ -877,7 +878,7 @@ def savefig(path, fig=None, close=True, **kwargs):
     if fig is None:
         fig = plt.gcf()
 
-    path = os.path.abspath(path)
+    path = pathlib.Path(path).resolve()
 
     kwargs["dpi"] = kwargs.get("dpi", 300)
     kwargs["transparent"] = kwargs.get("transparent", False)
@@ -1085,37 +1086,71 @@ def subplots_adjust(fig=None, inches=1):
         fig.subplots_adjust(top=top, right=right, bottom=bottom, left=left)
 
 
-def stitch_to_animation(paths, outpath=None, *, duration=0.5, palettesize=256, verbose=True):
-    """Stitch a series of images into an animation.
-
-    Currently supports animated gifs, other formats coming as needed.
+def stitch_to_animation(
+    paths,
+    outpath=None,
+    duration=0.5,
+    ignore_alpha: bool = True,
+    reduce: int = None,
+    verbose=True,
+    **kwargs,
+):
+    """Stitch a series of images into a gif.
 
     Parameters
     ----------
     paths : list of strings
-        Filepaths to the images to stitch together, in order of apperence.
+        Filepaths to the images to stitch together, in order of appearance.
     outpath : string (optional)
-        Path of output, including extension. If None, bases output path on path
-        of first path in `images`. Default is None.
+        Path of output, including extension. If None, bases output path on `paths[0]`. Default is None.
     duration : number or list of numbers (optional)
         Duration of (each) frame in seconds. Default is 0.5.
-    palettesize : int (optional)
-        The number of colors in the resulting animation. Input is rounded to
-        the nearest power of 2. Default is 256.
+    ignore_alpha : bool (optional)
+        When True, transparency is excluded from the gif and color palette may be higher res.
+    reduce : int (optional)
+        Reduces the resolution along both image dimensions by a factor of `reduce`.
     verbose : bool (optional)
         Toggle talkback. Default is True.
+
+    Returns:
+    --------
+    outpath : path-like
+        path to generated gif
     """
+    import contextlib
+    from PIL import Image
+
     # parse filename
     if outpath is None:
-        outpath = os.path.splitext(paths[0])[0] + ".gif"
+        outpath = pathlib.Path(paths[0]).with_suffix(".gif")
     # write
     t = wt_kit.Timer(verbose=False)
-    with t, iio.imopen(outpath, "w") as gif:
-        for p in paths:
-            frame = iio.imread(p)
-            gif.write(
-                frame, plugin="pillow", duration=duration * 1e3, loop=0, palettesize=palettesize
-            )
+
+    def process_imgs(imgs: List[Image.Image]):
+        count = 0
+        for img in imgs:
+            if verbose:
+                print(f"processing {count+1} / {len(paths)}...")
+            if ignore_alpha:
+                img = img.convert("RGB")
+            if reduce is not None:
+                img = img.reduce(reduce)
+            count += 1
+            yield img
+
+    with t, contextlib.ExitStack() as stack:
+        imgs = process_imgs(stack.enter_context(Image.open(p)) for p in paths)
+        img = next(imgs)
+        img.save(
+            fp=outpath,
+            format="GIF",
+            append_images=imgs,
+            save_all=True,
+            duration=duration * 1e3,
+            loop=0,
+            **kwargs,
+        )
+
     if verbose:
         interval = np.round(t.interval, 2)
         print("gif generated in {0} seconds - saved at {1}".format(interval, outpath))

setup.py

@@ -1,14 +1,14 @@
 #! /usr/bin/env python3
 
-import os
+import pathlib
 from setuptools import setup, find_packages
 
 
-here = os.path.abspath(os.path.dirname(__file__))
+here = pathlib.Path(__file__).resolve().parent
 
 
 def read(fname):
-    with open(os.path.join(here, fname)) as f:
+    with open(here / fname) as f:
         return f.read()
 
 
@@ -25,7 +25,7 @@ def read(fname):
     ]
 }
 
-with open(os.path.join(here, "WrightTools", "VERSION")) as version_file:
+with open(here / "WrightTools" / "VERSION") as version_file:
     version = version_file.read().strip()
 
 docs_require = ["sphinx", "sphinx-gallery==0.8.2", "sphinx-rtd-theme"]
@@ -37,7 +37,7 @@ def read(fname):
     python_requires=">=3.7",
     install_requires=[
         "h5py",
-        "imageio>=2.28.0",
+        "pillow",
         "matplotlib>=3.4.0",
         "numexpr",
         "numpy>=1.15.0,<2.0",