[Image-SIG] Array to Image transformations

[Christopher Barker]

Carlos da Silva Santos wrote:
> There are currently two PEPs related to this kind of problem. One is
> lead by Travis Oliphant of numpy and is about establishing a buffer
> protocol for data interchange. The second one is specifically related
> to passing image data between applications/toolkits.
> 
> http://www.python.org/dev/peps/pep-3118/
> http://www.python.org/dev/peps/pep-0368/
> 
> So I guess in the near future we will get rid of string conversions.

Actually, we already have, for numpy and PIL anyway:


# Added “fromarray” function, which takes an object implementing the 
NumPy array interface and creates a PIL Image from it. (from Travis 
Oliphant).

# Added NumPy array interface support (__array_interface__) to the Image 
class (based on code by Travis Oliphant). This allows you to easily 
convert between PIL image memories and NumPy arrays:

import numpy, Image

i = Image.open('lena.jpg')
a = numpy.asarray(i) # a is readonly
i = Image.fromarray(a)

See:

http://effbot.org/zone/pil-changes-116.htm

No data copying at all!

-Chris

-- 
Christopher Barker, Ph.D.
Oceanographer

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