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Meaning Error while reading tif image with saw in python?

I need to read a 2200x 2200 tif image and type uint16. I am using PIL library with anaconda python like this:

from PIL import Image
img = Image.open('test.tif')
img.imshow()

I got the following error: ValueError: tile cannot extend outside image

What could be causing this and how to fix it? I am using anaconda python3.6.1 version

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2 answers


The problem is that PIL wants to see ".tiff" at the end of the filename. You have ".tif". The solution is to rename your file to test.tiff.



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This is because there is a bug in the image encoding; the tiles in the TIF file do indeed propagate outside the image. You can confirm this by looking at the snippets:

img.tile

which will output something like:

[('tiff_lzw', (0, 0, 240, 240), 16, 'RGB'), ('tiff_lzw', (240, 0, 480, 240), 94905, 'RGB'), ... ('tiff_lzw', (720, 960, 960, 1200), 1711985, 'RGB'), ('tiff_lzw', (960, 960, 1200, 1200), 1730566, 'RGB')]



In the case of my example above, the image dimensions were 1000x1000

pixels, but obviously the tiles expand to 1200x1200

. You can either crop the image to the expected size (lose some information), or expand the image size to include all tiles. See examples here:

https://github.com/python-pillow/Pillow/issues/3044

ie, im.size = (1000, 1000)

orim.tile = [e for e in im.tile if e[1][2] < 1200 and e[1][3] < 1200]

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