From f25cece253377e57554d29c24d42fabe4feb3cf5 Mon Sep 17 00:00:00 2001
From: Andrew Murray <radarhere@users.noreply.github.com>
Date: Mon, 8 Apr 2019 13:04:16 +1000
Subject: [PATCH] Added ImageSequence all_frames

---
 Tests/test_imagesequence.py | 22 ++++++++++++++++++++++
 src/PIL/ImageSequence.py    | 22 ++++++++++++++++++++++
 2 files changed, 44 insertions(+)

diff --git a/Tests/test_imagesequence.py b/Tests/test_imagesequence.py
index 9fbf3fed8a7..53ac8375adf 100644
--- a/Tests/test_imagesequence.py
+++ b/Tests/test_imagesequence.py
@@ -69,3 +69,25 @@ def test_palette_mmap(self):
         im.seek(0)
         color2 = im.getpalette()[0:3]
         self.assertEqual(color1, color2)
+
+    def test_all_frames(self):
+        # Test a single image
+        im = Image.open('Tests/images/g4-multi.tiff')
+        ims = ImageSequence.all_frames(im)
+
+        self.assertEqual(len(ims), 3)
+        for i, im_frame in enumerate(ims):
+            self.assertFalse(im_frame is im)
+
+            im.seek(i)
+            self.assert_image_equal(im, im_frame)
+
+        # Test a series of images
+        ims = ImageSequence.all_frames([im, hopper(), im])
+        self.assertEqual(len(ims), 7)
+
+        # Test an operation
+        ims = ImageSequence.all_frames(im, lambda im_frame: im_frame.rotate(180))
+        for i, im_frame in enumerate(ims):
+            im.seek(i)
+            self.assert_image_equal(im.rotate(180), im_frame)
diff --git a/src/PIL/ImageSequence.py b/src/PIL/ImageSequence.py
index 1fc6e5de165..24115ddf034 100644
--- a/src/PIL/ImageSequence.py
+++ b/src/PIL/ImageSequence.py
@@ -54,3 +54,25 @@ def __next__(self):
 
     def next(self):
         return self.__next__()
+
+
+def all_frames(im, func=None):
+    """
+    Applies a given function to all frames in an image or a list of images.
+    The frames are returned as a list of separate images.
+
+    :param im: An image, or a list of images.
+    :param func: The function to apply to all of the image frames.
+    :returns: A list of images.
+    """
+    if not isinstance(im, list):
+        im = [im]
+
+    ims = []
+    for imSequence in im:
+        current = imSequence.tell()
+
+        ims += [im_frame.copy() for im_frame in Iterator(imSequence)]
+
+        imSequence.seek(current)
+    return [func(im) for im in ims] if func else ims