python生成指定尺寸的缩略图

复制代码 代码如下:

def MakeThumb(path, sizes=(75, 32, 16)):
"""
缩略图生成程序 by Neil Chen
sizes 参数传递要生成的尺寸，可以生成多种尺寸
"""
base, ext = os.path.splitext(path)
try:
im = Image.open(path)
except IOError:
return
mode = im.mode
if mode not in ('L', 'RGB'):
if mode == 'RGBA':

透明图片需要加白色底

        alpha = im.split()[3]  
        bgmask = alpha.point(lambda x: 255-x)  
        im = im.convert('RGB')  
        # paste(color, box, mask)  
        im.paste((255,255,255), None, bgmask)  
    else:  
        im = im.convert('RGB')

width, height = im.size  
if width == height:  
    region = im  
else:  
    if width > height:  
        delta = (width - height)/2  
        box = (delta, 0, delta+height, height)  
    else:  
        delta = (height - width)/2  
        box = (0, delta, width, delta+width)  
    region = im.crop(box)

for size in sizes:  
    filename = base + "_" + "%sx%s" % (str(size), str(size)) + ".jpg"  
    thumb = region.resize((size,size), Image.ANTIALIAS)  
    thumb.save(filename, quality=100) # 默认 JPEG 保存质量是 75, 不太清楚。可选值(0~100)