python使用PIL库给图片添加水印，,python 真是越来越

python使用PIL库给图片添加水印，,python 真是越来越

python 真是越来越喜欢了，以前要一天的工作，现在用python 几个小时就能处理完，而且效果很理想～～ 因为网站经常有采集现象发生，所以想给所有图片增加水印，即使采走也帮我做宣传。

为了能使加的水印漂亮，水印文件想使用png格式，这样就能保证水印的平滑 漂亮，而且加上发光效果更帅～ 哈哈

python代码总是很短 ，经过几次调整，已经忘了最早的出处了 反正都是分享～～

# -*- coding: utf-8 -*-import Image, ImageEnhancePOSITION = ('LEFTTOP','RIGHTTOP','CENTER','LEFTBOTTOM','RIGHTBOTTOM')PADDING = 10MARKIMAGE = 'water.png'def 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(imagefile, markfile, position=POSITION[4], opacity=1):    """Adds a watermark to an image."""        im = Image.open(imagefile)    mark = Image.open(markfile)        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 == 'title':        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))    elif position == POSITION[0]:        #lefttop        position = (PADDING,PADDING)        layer.paste(mark, position)    elif position == POSITION[1]:        #righttop        position = (im.size[0] - mark.size[0]-PADDING, PADDING)        layer.paste(mark, position)    elif position == POSITION[2]:        #center        position = ((im.size[0] - mark.size[0])/2,(im.size[1] - mark.size[1])/2)        layer.paste(mark, position)    elif position == POSITION[3]:        #left bottom        position = (PADDING,im.size[1] - mark.size[1]-PADDING,)        layer.paste(mark, position)    else:        #right bottom (default)        position = (im.size[0] - mark.size[0]-PADDING, im.size[1] - mark.size[1]-PADDING,)        layer.paste(mark, position)    # composite the watermark with the layer    return Image.composite(layer, im, layer)

用法：

watermark(new_image_s_filename,MARKIMAGE,POSITION[4],opacity=1).save(new_image_s_filename,quality=90)

很好用，效果特别好～～