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Integration with Pillow
=======================
https://pillow.readthedocs.io
Creating an ImageSurface from a PIL Image:
.. code:: python
import cairo
import PIL.Image as Image
def from_pil(im: Image, alpha: float=1.0, format: cairo.Format=cairo.FORMAT_ARGB32) -> cairo.ImageSurface:
"""
:param im: Pillow Image
:param alpha: 0..1 alpha to add to non-alpha images
:param format: Pixel format for output surface
"""
assert format in (
cairo.FORMAT_RGB24,
cairo.FORMAT_ARGB32,
), f"Unsupported pixel format: {format}"
if 'A' not in im.getbands():
im.putalpha(int(alpha * 256.))
arr = bytearray(im.tobytes('raw', 'BGRa'))
surface = cairo.ImageSurface.create_for_data(arr, format, im.width, im.height)
return surface
filename = 'test.jpeg'
# Open image to an ARGB32 ImageSurface
im = Image.open(filename)
surface1 = from_pil(im)
# Open image to an RGB24 ImageSurface
im = Image.open(filename)
surface2 = from_pil(im, format=cairo.FORMAT_RGB24)
# Open image to an ARGB32 ImageSurface, 50% opacity
im = Image.open(filename)
surface3 = from_pil(im, alpha=0.5, format=cairo.FORMAT_ARGB32)
Converting an ImageSurface to a PIL Image:
.. code:: python
import cairo
import PIL.Image as Image
def to_pil(surface: cairo.ImageSurface) -> Image:
format = surface.get_format()
size = (surface.get_width(), surface.get_height())
stride = surface.get_stride()
with surface.get_data() as memory:
if format == cairo.Format.RGB24:
return Image.frombuffer(
"RGB", size, memory.tobytes(),
'raw', "BGRX", stride)
elif format == cairo.Format.ARGB32:
return Image.frombuffer(
"RGBA", size, memory.tobytes(),
'raw', "BGRa", stride)
else:
raise NotImplementedError(repr(format))
# Create an image surface from a PNG file (or any other source)
surface = cairo.ImageSurface.create_from_png("test.png")
# Convert to a PIL Image
im = to_pil(surface)
# Use Pillow to store it as a JPEG
im.save("result.jpg")
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