PIL之基础应用

>>> from PIL import Image
>>> #读取图像文件
...
>>> gal=Image.open('/Users/similarface/PycharmProjects/mybook/products/2016/06/13/1_TIBX78J.png')
>>> #查看文件大小
...
>>> gal.size
(100, 100)
>>> #显示文件
...
>>> gal.show()

>>> #显示灰度图像
...
>>> gal.convert('L').show()

>>> gal.mode
'RGBA'
>>> gal.format
'PNG'

'''
将图片的格式转化成jpg格式的
'''
filelist=[]
for infile in filelist:
    f, e = os.path.splitext(infile)
    outfile = f + ".jpg"
    if infile != outfile:
        try:
            Image.open(infile).save(outfile)
        except IOError:
            print "cannot convert", infile

'''
将图片生成缩略图
'''
size = 128, 128
for infile in sys.argv[1:]:
    outfile = os.path.splitext(infile)[0] + ".thumbnail"
    if infile != outfile:
        try:
            im = Image.open(infile)
            im.thumbnail(size)
            im.save(outfile, "JPEG")
        except IOError:
            print "cannot create thumbnail for", infile

#获取文件基础消息
import Image
for infile in filelist:
    try:
        im = Image.open(infile)
        print infile, im.format, "%dx%d" % im.size, im.mode
    except IOError:
        pass

'''
Cutting, Pasting and Merging Images #
'''

>>> box=(0,25,70,50)
>>> region=gal.crop(box)
>>> region.show()
#存储的图片是从原始文件左上角为参照原点（0，25）开始
#70长 50高的图片

#将图片旋转180
region=region.transpose(Image.ROTATE_180)
>>> region.save('/tmp/sub.png',"PNG")

def roll(image, delta):
    "Roll an image sideways"
    xsize, ysize = image.size

    delta = delta % xsize
    if delta == 0:
        return image
    #图像裁减
    part1 = image.crop((0, 0, delta, ysize))
    part2 = image.crop((delta, 0, xsize, ysize))
    #图像粘贴
    image.paste(part2, (0, 0, xsize-delta, ysize))
    image.paste(part1, (xsize-delta, 0, xsize, ysize))
    return image    

#将颜色通道分割 ［这儿是rgba的图像格式，有rgb的］
r,g,b ,a= gal.split()

#合并通道
im = Image.merge("RGB", (b, g, r))
im.show()
im = Image.merge("RGB", (b, g, a))

>>> gal=Image.open('/Users/similarface/PycharmProjects/mybook/products/2016/06/13/1_TIBX78J.png')
>>>
>>> gal.resize((128,128))
<PIL.Image.Image image mode=RGBA size=128x128 at 0x108AECF90>
#重新设置大大
>>> gal.resize((1128,1128)).show()
#旋转45度
>>> gal.rotate(45).show()
#旋转30度
>>> gal.rotate(30).show()

#图像左右对称图
gal.transpose(Image.FLIP_LEFT_RIGHT).show()
#图像上下对称图
gal.transpose(Image.FLIP_TOP_BOTTOM)
#图像旋转
out = im.transpose(Image.ROTATE_90)
out = im.transpose(Image.ROTATE_180)
out = im.transpose(Image.ROTATE_270)