[Image-SIG] silent corruption of FillOrder: lsb-to-msb TIFF reads?

[K Schutte]

>From what I remember the same is valid for other not-one-char-per-pixel
TIFF file formats, including 16 and 32 bit integers. Thus, with PIL you
currently only can read your 'native' file format correctly.

Klamer

Jeff Breidenbach wrote:

> I'm getting unusual results when reading a set of TIFF files.
> PIL reads the file without complaint, but appears to be silently
> corrupting the image. The following commands save out a bunch of
> colorful noise.
>
> >>> import Image
> >>> a = Image.open("foo.tif")
> >>> a.save("bar.bmp")
>
> Looking at the output, I suspect that PIL's TIFF reader
> is ignoring the FillOrder tag. Even more suspicious, when I
> convert the TIFF to  FillOrder: msb-to-lsb, no such corruption
> occurs.
>
> Any comments? Ideally, I'd love for PIL to be able to read
> this type of TIFF file, or at least have a better grasp
> of its own limitations. I've attached the TIFF characteristics
> below.
>
> Cheers,
> Jeff
>
> TIFF Directory at offset 0x5c4e9ee
>   Image Width: 4913 Image Length: 6567
>   Resolution: 600, 600 pixels/inch
>   Bits/Sample: 8
>   Compression Scheme: None
>   Photometric Interpretation: RGB color
>   FillOrder: lsb-to-msb
>   Orientation: row 0 top, col 0 lhs
>   Samples/Pixel: 3
>   Rows/Strip: 1
>   Planar Configuration: single image plane
> Image: foo.tif
>   Format: TIFF (Tagged Image File Format)
>   Geometry: 4913x6567
>   Class: DirectClass
>   Type: true color
>   Depth: 8 bits-per-pixel component
>   Colors: 165833
>   Resolution: 600x600 pixels/inch
>   Filesize: 92.4m
>   Interlace: None
>   Background Color: grey100
>   Border Color: #DFDFDF
>   Matte Color: grey74
>   Dispose: Undefined
>   Iterations: 0
>   Compression: None
>
>
> --
> Jeff Breidenbach <jbreiden "at" parc.com>
> Member of Research Staff, PARC
>
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