Color-/Lineshifts under Windows?

[Hauke Heibel]

On Mon, Aug 9, 2010 at 5:08 PM, Adam Goode <agoode at andrew.cmu.edu> wrote:
>> (...) It is though funny, that three different
>> programs (xnview, photoshop, openslide resp. jpeglib) give me three
>> different results when it comes to the color of pixel (48,204) of the
>> file Data0014.dat - no clue why this should and could happen.
>
> How different are the values? You may be seeing the result of color
> correction. Also, Photoshop almost certainly uses a different JPEG
> library, and will result in slight variations in individual pixels.

Just minor variations - I am just surprised that this can happen at
all and that there does not seem to be a common agreement on how to
restore the intensities. At least the intensities are similar. ;)

ms paint, xnview: (131,91,143)
photoshop: (131,90,146)
gimp, openslide: (133,89,148)

>> (...) The problem is that even the shape of the cells changed in
>> test7-09.ppm and not only the colors.
>
> Can you try with the MIRAX viewer? I think it will output similar
> dimensions to OpenSlide.

I think I did not make clear what I meant. I was under the
impressions, that it were possible to simply take the first JPEG from
Data0014.dat and compare the OpenSlide output test7-09.ppm with that
one. Probably I was wrong after reading your second mail but the JPEG
(from the .dat file which I attached to this e-mail) looks as if it
were a simple down-scaled sub-section of the original image.

Anyways, just to make things more clear, I attached the blending too.
It's an animated GIF. One frame shows the JPEG from Data0014.dat and
the other one the test7-09.ppm overlaid as good as it was possible for
me. On the left-hand-side it looks ok, but on the right-hand-side
there is a discontinuity.

As a side note, I got the idea to look into Data0014.dat because it is
the only file used for layer 9 when calling read_from_one_jpeg -- i.e.
test7-09.ppm is created from that file and that file only if I
understand you code correctly.

Now, let me double check the second e-mail.

Regards,
- Hauke
-------------- next part --------------
A non-text attachment was scrubbed...
Name: blend.gif
Type: image/gif
Size: 5683 bytes
Desc: not available
Url : http://lists.andrew.cmu.edu/pipermail/openslide-users/attachments/20100809/087d3b9c/attachment.gif 
-------------- next part --------------
A non-text attachment was scrubbed...
Name: Data0014 - first jpeg.jpg
Type: image/jpeg
Size: 3492 bytes
Desc: not available
Url : http://lists.andrew.cmu.edu/pipermail/openslide-users/attachments/20100809/087d3b9c/attachment.jpg