Can I check something with you guys [Solved]
On Tue, 27 Nov 2007 22:22:59 -0500, Andrew Kalten
wrote:
Glenn wrote:
Is this glaringly obvious to you guys as well.
The only way to answer this question objectively is
to subtract one image from the other.
Using Linux/GNU software (it would be very hard to accomplish
on a stock MS Windows system) I converted both JPEG images
to an uncompressed format, subtracted the image data byte
by byte, and then recompressed back to JPEG (to get a smaller
file size for posting).
The subtraction will reveal any discrepancy. If the images
are identical, the values will subtract to zero and the appearance
will be black. The result is attached.
As can be seen, the difference image is virtually all black, except
for a slightly visible band of lightness corresponding to the water
areas. This slight difference, only barely perceptible, is likely the
result of different compression qualities between the two images.
Conclusion: The images are virtually identical. Any difference will
be beyond perception.
AK
Hello,
In addition, IMG_6297 copy.jpg contained 30,172 bytes of extraneous
data, compared with warbirdz_12327.jpg, which contained only 79 such
bytes, as determined by comparing file sizes before and after
processing with jStrip v3.3. And, actually, there are any number of
Windows compatible graphics programs that can accomplish this task
easily, but no, they do not ship with Windows. As to whether the
difference is beyond perception, I am not prepared to state such a
conclusion so definitively.
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