python处理圆角图片、圆形图片的例子

    ima = Image.open("test.jpg").convert("RGBA")

    size = ima.size

    # 因为是要圆形，所以需要正方形的图片

    r2 = min(size[0], size[1])

    if size[0] != size[1]:

        ima = ima.resize((r2, r2), Image.ANTIALIAS)

    imb = Image.new('RGBA', (r2, r2),(255,255,255,0))

    pima = ima.load()

    pimb = imb.load()

    r = float(r2/2) #圆心横坐标

    for i in range(r2):

        for j in range(r2):

            lx = abs(i-r+0.5) #到圆心距离的横坐标

            ly = abs(j-r+0.5)#到圆心距离的纵坐标

            l  = pow(lx,2) + pow(ly,2)

            if l <= pow(r, 2):

                pimb[i,j] = pima[i,j]

    imb.save("test_circle.png")

    im = Image.open("test.jpg").convert("RGBA")

    rad = 10  # 设置半径 

    circle = Image.new('L', (rad * 2, rad * 2), 0)

    draw = ImageDraw.Draw(circle)

    draw.ellipse((0, 0, rad * 2, rad * 2), fill=255)

    alpha = Image.new('L', im.size, 255)

    w, h = im.size

    alpha.paste(circle.crop((0, 0, rad, rad)), (0, 0))

    alpha.paste(circle.crop((0, rad, rad, rad * 2)), (0, h – rad))

    alpha.paste(circle.crop((rad, 0, rad * 2, rad)), (w – rad, 0))

    alpha.paste(circle.crop((rad, rad, rad * 2, rad * 2)), (w – rad, h – rad))

    im.putalpha(alpha)

    im.save('test_circle_corder.png')

    ima = Image.open("test.jpg").convert("RGBA")

    size = ima.size

    r2 = min(size[0], size[1])

    if size[0] != size[1]:

        ima = ima.resize((r2, r2), Image.ANTIALIAS)

    circle = Image.new('L', (r2, r2), 0)

    draw = ImageDraw.Draw(circle)

    draw.ellipse((0, 0, r2, r2), fill=255)

    alpha = Image.new('L', (r2, r2), 255)

    alpha.paste(circle, (0, 0))

    ima.putalpha(alpha)

    ima.save('test_circle.png')