本文实例讲述了python使用PIL模块实现给图片打水印的方法。分享给大家供大家参考。具体实现方法如下：
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import Image, ImageEnhancedef reduce_opacity(im, opacity): """Returns an image with reduced opacity.""" assert opacity >= 0 and opacity <= 1 if im.mode != 'RGBA': im = im.convert('RGBA') else: im = im.copy() alpha = im.split()[3] alpha = ImageEnhance.Brightness(alpha).enhance(opacity) im.putalpha(alpha) return imdef watermark(im, mark, position, opacity=1): """Adds a watermark to an image.""" if opacity < 1: mark = reduce_opacity(mark, opacity) if im.mode != 'RGBA': im = im.convert('RGBA') # create a transparent layer the size of the image and draw the # watermark in that layer. layer = Image.new('RGBA', im.size, (0,0,0,0)) if position == 'tile': for y in range(0, im.size[1], mark.size[1]): for x in range(0, im.size[0], mark.size[0]): layer.paste(mark, (x, y)) elif position == 'scale': # scale, but preserve the aspect ratio ratio = min( float(im.size[0]) / mark.size[0], float(im.size[1]) / mark.size[1]) w = int(mark.size[0] * ratio) h = int(mark.size[1] * ratio) mark = mark.resize((w, h)) layer.paste(mark, ((im.size[0] - w) / 2, (im.size[1] - h) / 2)) else: layer.paste(mark, position) # composite the watermark with the layer return Image.composite(layer, im, layer)def test(): im = Image.open('test.png') mark = Image.open('overlay.png') watermark(im, mark, 'tile', 0.5).show() watermark(im, mark, 'scale', 1.0).show() watermark(im, mark, (100, 100), 0.5).show()if __name__ == '__main__': test() |
希望本文所述对大家的Python程序设计有所帮助。
