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)