Is there an Image.point() method in PIL that allows you to operate on all three channels at once?

I want to write a point filter that is based on the red, green and blue channels for each pixel, but it appears that this might fall short of point()'s abilities -- it开发者_如何学Go seems that it operates on a single pixel in a single channel at a time. I'd like to do something like this:

def colorswap(pixel):
    """Shifts the channels of the image."""
    return (pixel[1], pixel[2], pixel[0])
image.point(colorswap)

Is there an equivalent method that lets me use a filter that takes in a 3-tuple of RGB values and output a new 3-tuple?

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You can use the load method to get fast access to all the pixels.

def colorswap(pixel):
    """Shifts the channels of the image."""
    return (pixel[1], pixel[2], pixel[0])

def applyfilter(image, func):
    """ Applies a function to each pixel of an image."""
    width,height = im.size
    pixel = image.load()
    for y in range(0, height):
        for x in range(0, width):
            pixel[x,y] = func(pixel[x,y])

applyfilter(image, colorswap)

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Based on the responses to date, I'd guess the answer is 'no'.

But you could always employ numpy to do this kind of work efficiently:

def colorswap(pixel):
    """Shifts the channels of the image."""
    return (pixel[1], pixel[2], pixel[0])

def npoint(img, func):
    import numpy as np
    a = np.asarray(img).copy()
    r = a[:,:,0]
    g = a[:,:,1]
    b = a[:,:,2]
    r[:],g[:],b[:] = func((r,g,b))
    return Image.fromarray(a,img.mode)

img = Image.open('test.png')
img2 = npoint(img, colorswap)
img2.save('test2.png')

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Bonus: It looks like the Image class is not read-only, which means you can make your new npoint function feel even more like point (not recommended unless like confusing people):

Image.Image.npoint = npoint

img = Image.open('test.png')
img2 = img.npoint(colorswap)