Reading PhotometricInterpretation CFA TIFF file fails

[kif]

Dear Pillow developers

I am the developer of FabIO and we rely on Pillow to read some file-formats which are not specific to X-ray detectors.

One of our user reported a file which could not be read with Pillow but could with tiffile, he provided a file of shape2880x2880 of uint16 available in this issue: https://github.com/silx-kit/fabio/issues/458

The error message is

>>> PIL.Image.open("test.tif")
---------------------------------------------------------------------------
UnidentifiedImageError                    Traceback (most recent call last)
<ipython-input-18-b037e95b0993> in <module>
----> 1 PIL.Image.open("test.tif")

~/.venv/py39/lib/python3.9/site-packages/PIL/Image.py in open(fp, mode, formats)
   3028     for message in accept_warnings:
   3029         warnings.warn(message)
-> 3030     raise UnidentifiedImageError(
   3031         "cannot identify image file %r" % (filename if filename else fp)
   3032     )

UnidentifiedImageError: cannot identify image file 'test.tif'

The user provides some hints in the fabio issue about PhotometricInterpretation which may be uninterpreted... since the value in question is available, I suspect it is rather a bug somewhere in the parser.

I can help but I will need a minimum guidance in the structure of Pillow.

Cheers,

Jerome

[radarhere]

Hi.

If I modify my Image.py like so

diff --git a/src/PIL/Image.py b/src/PIL/Image.py
index 6ecd5fac8..bdb8f4af7 100644
--- a/src/PIL/Image.py
+++ b/src/PIL/Image.py
@@ -2982,6 +2982,8 @@ def open(fp, mode="r", formats=None):
                 # Leave disabled by default, spams the logs with image
                 # opening failures that are entirely expected.
                 # logger.debug("", exc_info=True)
+                if i == "TIFF":
+                    raise
                 continue
             except BaseException:
                 if exclusive_fp:

and then try to open the file, I get

Traceback (most recent call last):
  File "PIL/TiffImagePlugin.py", line 1324, in _setup
KeyError: (b'II', 32803, (1,), 1, (16,), ())

The above exception was the direct cause of the following exception:

Traceback (most recent call last):
  File "demo.py", line 2, in <module>
    im = Image.open('test.tif')
  File "PIL/Image.py", line 2994, in open
  File "PIL/Image.py", line 2978, in _open_core
  File "PIL/TiffImagePlugin.py", line 1032, in __init__
  File "PIL/ImageFile.py", line 111, in __init__
  File "PIL/TiffImagePlugin.py", line 1057, in _open
  File "PIL/TiffImagePlugin.py", line 1114, in _seek
  File "PIL/TiffImagePlugin.py", line 1327, in _setup
SyntaxError: unknown pixel mode

The second value in (b'II', 32803, (1,), 1, (16,), ()) is PhotometricInterpretation. If PhotometricInterpretation were 1 (MINISBLACK), we would have an entry for that - https://github.com/python-pillow/Pillow/blob/fcb87ecbe171f959ff62cefe0e33061b24d3de5a/src/PIL/TiffImagePlugin.py#L170

I see that https://www.awaresystems.be/imaging/tiff/tifftags/photometricinterpretation.html does list 32803 = CFA.

So I agree that it is a value we have not supported, rather than a bug from faulty logic.

[radarhere]

In your original issue, you reported that this was fixed.

Any info on how you did that?

[radarhere]

(b'II', 32803, (1,), 1, (16,), ()) also covers one of the files in #6482, so I'm going to close this as part of that.