77 lines
1.8 KiB
Python
77 lines
1.8 KiB
Python
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#
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# The Python Imaging Library.
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# $Id$
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#
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# sequence support classes
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#
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# history:
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# 1997-02-20 fl Created
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#
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# Copyright (c) 1997 by Secret Labs AB.
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# Copyright (c) 1997 by Fredrik Lundh.
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#
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# See the README file for information on usage and redistribution.
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#
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##
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class Iterator:
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"""
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This class implements an iterator object that can be used to loop
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over an image sequence.
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You can use the ``[]`` operator to access elements by index. This operator
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will raise an :py:exc:`IndexError` if you try to access a nonexistent
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frame.
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:param im: An image object.
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"""
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def __init__(self, im):
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if not hasattr(im, "seek"):
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msg = "im must have seek method"
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raise AttributeError(msg)
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self.im = im
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self.position = getattr(self.im, "_min_frame", 0)
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def __getitem__(self, ix):
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try:
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self.im.seek(ix)
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return self.im
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except EOFError as e:
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raise IndexError from e # end of sequence
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def __iter__(self):
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return self
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def __next__(self):
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try:
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self.im.seek(self.position)
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self.position += 1
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return self.im
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except EOFError as e:
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raise StopIteration from e
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def all_frames(im, func=None):
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"""
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Applies a given function to all frames in an image or a list of images.
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The frames are returned as a list of separate images.
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:param im: An image, or a list of images.
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:param func: The function to apply to all of the image frames.
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:returns: A list of images.
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"""
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if not isinstance(im, list):
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im = [im]
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ims = []
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for imSequence in im:
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current = imSequence.tell()
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ims += [im_frame.copy() for im_frame in Iterator(imSequence)]
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imSequence.seek(current)
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return [func(im) for im in ims] if func else ims
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