30 lines
1.0 KiB
Python
30 lines
1.0 KiB
Python
from PIL import Image
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def shrink_and_paste_on_blank(current_image, mask_width, mask_height):
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"""
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Decreases size of current_image by mask_width pixels from each side,
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then adds a mask_width width transparent frame,
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so that the image the function returns is the same size as the input.
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:param current_image: input image to transform
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:param mask_width: width in pixels to shrink from each side
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:param mask_height: height in pixels to shrink from each side
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"""
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# calculate new dimensions
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width, height = current_image.size
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new_width = width - 2 * mask_width
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new_height = height - 2 * mask_height
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# resize and paste onto blank image
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prev_image = current_image.resize((new_width, new_height), Image.LANCZOS)
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blank_image = Image.new("RGBA", (width, height), (0, 0, 0, 1))
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paste_box = (
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mask_width,
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mask_height,
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mask_width + new_width,
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mask_height + new_height
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)
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blank_image.paste(prev_image, paste_box)
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return blank_image
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