How to resize a tiff image with multiple channels?

问题

I have a tiff image of size 21 X 513 X 513 where (513, 513) is the height and width of the image containing 21 channels. How can I resize this image to 21 X 500 X 375?

I am trying to use PILLOW to do so. But can't figure out if I am doing something wrong.

>>> from PIL import Image
>>> from tifffile import imread
>>> img = Image.open('new.tif')
>>> img

    <PIL.TiffImagePlugin.TiffImageFile image mode=F size=513x513 at 0x7FB0C8E5B940>

>>> resized_img = img.resize((500, 375), Image.ANTIALIAS)
>>> resized_img

    <PIL.Image.Image image mode=F size=500x375 at 0x7FB0C8E5B908>

>>> resized_img.save('temp.tif')

>>> img = imread('temp.tif')
>>> img.shape
  (500, 375)

The channel information is lost here.

回答1:

Try using tifffile and scikit-image:

from tifffile import imread, imwrite
from skimage.transform import resize

data = imread('2009_003961_SEG.tif')
resized_data = resize(data, (375, 500, 21))
imwrite('multi-channel_resized.tif', resized_data, planarconfig='CONTIG')

The file 2009_003961_SEG.tif linked in comment98601187_55975161 is not a multi-channel 513x513x21 image. Instead the file contains 513 images of size 513x21. The tifffile library will read the series of images in the file and return it as a numpy array of shape 513x513x21.

To resize the numpy array to 375x500x21, use skimage.transform.resize (or scipy.ndimage.zoom). It might be faster to resize the 21 channels separately.

To write a TIFF file containing a single multi-channel image of size 375x500x21 using tifffile, specify the planarconfig parameter. Not many libraries or apps can handle such files.

回答2:

You can use OpenCV to resize your image. I was able to resize a TIFF format image using following code:

import cv2

file = "image.tiff"
img = cv2.imread(file)
print("original image size: ", img.shape)

new_img = cv2.resize(img,(img.shape[1]-100,img.shape[0]-100))  # cv2.resize(image,(width,height))
print("resized image size: ", new_img.shape)

Output:
original image size: (512, 768, 3)
resized image size: (412, 668, 3)

Opencv takes INTER_LINEAR as default interpolation method.

You can change interpolation by providing an additional argument

new_img = cv2.resize(img,(img.shape[1]-100,img.shape[0]-100),interpolation=cv2.INTER_AREA)

Read more about available interpolation method here: https://docs.opencv.org/2.4/modules/imgproc/doc/geometric_transformations.html?highlight=resize#resize

来源：https://stackoverflow.com/questions/55974717/how-to-resize-a-tiff-image-with-multiple-channels