In PIL this is easy.
The following code preferably uses cache (just a simple python
dictionary) to avoid the overhead of generating the same transparency
masks. So typical use would be:
cache = {}
for image in images:
thumbnail = image_round(image.thumbnail(size, filter), cache, radius)
Here is the code for rounded corners:
# Rounded corners
# (c) 2008 www.stani.be
# License: same as PIL
CROSS = _t('Cross')
ROUNDED = _t('Rounded')
SQUARE = _t('Square')
CORNERS = [ROUNDED,SQUARE,CROSS]
CORNER_ID = 'rounded_corner_r%d_f%d'
CROSS_POS = (CROSS,CROSS,CROSS,CROSS)
ROUNDED_POS = (ROUNDED,ROUNDED,ROUNDED,ROUNDED)
ROUNDED_RECTANGLE_ID = 'rounded_rectangle_r%d_f%d_s%s_p%s'
def round_image(image,cache={},radius=100,fill=255,pos=ROUNDED_POS,
back_colour='#FFFFFF'):
if image.mode != 'RGBA':
image = image.convert('RGBA')
mask = create_rounded_rectangle(image.size,cache,radius,fill,pos)
image.paste(Image.new('RGB',image.size,back_colour),(0,0),
ImageChops.invert(mask))
image.putalpha(mask)
return image
def create_corner(radius=100,fill=255,factor=2):
corner = Image.new('L',(factor*radius,factor*radius),0)
draw = ImageDraw.Draw(corner)
draw.pieslice((0,0,2*factor*radius,2*factor*radius),180,270,fill=fill)
corner = corner.resize((radius,radius),Image.ANTIALIAS)
return corner
def create_rounded_rectangle(size=(600,400),cache={},radius=100,fill=255,
pos=ROUNDED_POS):
#rounded_rectangle
im_x, im_y = size
rounded_rectangle_id = ROUNDED_RECTANGLE_ID%(radius,fill,size,pos)
if cache.has_key(rounded_rectangle_id):
return cache[rounded_rectangle_id]
else:
#cross
cross_id = ROUNDED_RECTANGLE_ID%(radius,fill,size,CROSS_POS)
if cache.has_key(cross_id):
cross = cache[cross_id]
else:
cross = cache[cross_id] = Image.new('L',size,0)
draw = ImageDraw.Draw(cross)
draw.rectangle((radius,0,im_x-radius,im_y),fill=fill)
draw.rectangle((0,radius,im_x,im_y-radius),fill=fill)
if pos==CROSS_POS:
return cross
#corner
corner_id = CORNER_ID%(radius,fill)
if cache.has_key(corner_id):
corner = cache[corner_id]
else:
corner = cache[corner_id] = create_corner(radius,fill)
#rounded rectangle
rectangle = Image.new('L',(radius,radius),255)
rounded_rectangle = cross.copy()
for index, angle in enumerate(pos):
if angle == CROSS:
break
if angle == ROUNDED:
element = corner
else:
element = rectangle
if index%2:
x = im_x-radius
element = element.transpose(Image.FLIP_LEFT_RIGHT)
else:
x = 0
if index < 2:
y = 0
else:
y = im_y-radius
element = element.transpose(Image.FLIP_TOP_BOTTOM)
rounded_rectangle.paste(element,(x,y))
cache[rounded_rectangle_id] = rounded_rectangle
return rounded_rectangle
Alex K schreef:
> Hello,
>
> Would anyone know how to generate thumbnails with rounded corners
> using PIL? I'm also considering imagemagick if PIL turns out not to be
> appropriate for the task.
>
> Thank you so much,
>
> Alex
> _______________________________________________
> Image-SIG maillist - Image-SIG@python.org
> http://mail.python.org/mailman/listinfo/image-sig
>
_______________________________________________
Image-SIG maillist - Image-SIG@python.org
http://mail.python.org/mailman/listinfo/image-sig
