[Solved]-Resize image maintaining aspect ratio AND making portrait and landscape images exact same size?

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19👍

✅

Here is my take on doing a padded fit for an image:

#!/usr/bin/env python

from PIL import Image, ImageChops

F_IN = "/path/to/image_in.jpg"
F_OUT = "/path/to/image_out.jpg"

size = (80,80)

image = Image.open(F_IN)
image.thumbnail(size, Image.ANTIALIAS)
image_size = image.size

thumb = image.crop( (0, 0, size[0], size[1]) )

offset_x = max( (size[0] - image_size[0]) / 2, 0 )
offset_y = max( (size[1] - image_size[1]) / 2, 0 )

thumb = ImageChops.offset(thumb, offset_x, offset_y)
thumb.save(F_OUT)

It first uses the thumbnail operation to bring the image down to within your original bounds and preserving the aspect. Then it crops it back out to actually fill the size of your bounds (since unless the original image was square, it will be smaller now), and we find the proper offset to center the image. The image is offset to the center, so you end up with black padding but no image cropping.

Unless you can make a really sensible guess at a proper center crop without losing possible important image data on the edges, a padded fit approach will work better.

Update

Here is a version that can do either center crop or pad fit.

#!/usr/bin/env python

from PIL import Image, ImageChops, ImageOps

def makeThumb(f_in, f_out, size=(80,80), pad=False):

    image = Image.open(f_in)
    image.thumbnail(size, Image.ANTIALIAS)
    image_size = image.size

    if pad:
        thumb = image.crop( (0, 0, size[0], size[1]) )

        offset_x = max( (size[0] - image_size[0]) / 2, 0 )
        offset_y = max( (size[1] - image_size[1]) / 2, 0 )

        thumb = ImageChops.offset(thumb, offset_x, offset_y)

    else:
        thumb = ImageOps.fit(image, size, Image.ANTIALIAS, (0.5, 0.5))

    thumb.save(f_out)


source = "/path/to/source/image.JPG"

makeThumb(source, "/path/to/source/image_padded.JPG", pad=True)
makeThumb(source, "/path/to/source/image_centerCropped.JPG", pad=False)
👤jdi

2👍

Obviously, you would need to crop or pad the images. You could do something like below to get a maximal centered crop according to the aspect ratio of the thumbnails (untested):

aspect = lambda size: float(size[0]) / float(size[1])
sa = aspect(size)
if aspect(im.size) > sa:
    width = int(sa * im.size[1])
    left = (im.size[0] - width) / 2
    im = im.crop((left, 0, left + width, im.size[1]))
else:
    height = int(im.size[0] / sa)
    top = (im.size[1] - height) / 2
    im = im.crop((0, top, im.size[0], top + height))
im.thumbnail(size, Image.ANTIALIAS)
👤ezod

0👍

If you use easy-thumbnails you’ll need to set crop to True and upscale to True to always fill-up the space (have the exact same dimensions).

Ex: makes image_2 fits in image_1 dimensions:

    thumbnailer = get_thumbnailer(image_2)
    thumbnail = thumbnailer.generate_thumbnail(thumbnail_options={
        'crop': True,
        'upscale': True,
        'size': image_1.size
    })
    image_2 = thumbnail.image
👤François Constant

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