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"""Image operations.""" |
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from copy import deepcopy |
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from PIL import Image |
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def center_crop(im: Image): |
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width, height = im.size |
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new_width = width if width < height else height |
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new_height = height if height < width else width |
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left = (width - new_width)/2 |
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top = (height - new_height)/2 |
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right = (width + new_width)/2 |
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bottom = (height + new_height)/2 |
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im = im.crop((left, top, right, bottom)) |
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return im |
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def pad_to_square(im: Image, color=(0, 0, 0)): |
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im = deepcopy(im) |
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width, height = im.size |
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vert_pad = (max(width, height) - height) // 2 |
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hor_pad = (max(width, height) - width) // 2 |
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if len(im.mode) == 3: |
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color = (0, 0, 0) |
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elif len(im.mode) == 1: |
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color = 0 |
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else: |
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raise ValueError(f"Image mode not supported. Image has {im.mode} channels.") |
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return add_margin(im, vert_pad, hor_pad, vert_pad, hor_pad, color=color) |
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def add_margin(pil_img, top, right, bottom, left, color=(0, 0, 0)): |
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"""Ref: https://note.nkmk.me/en/python-pillow-add-margin-expand-canvas/""" |
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width, height = pil_img.size |
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new_width = width + right + left |
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new_height = height + top + bottom |
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result = Image.new(pil_img.mode, (new_width, new_height), color) |
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result.paste(pil_img, (left, top)) |
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return result |
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