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Re: filmscanners: File format
Without wishing to add to you "pain" ;-), I was surprised to determine
that this exact situation (the "leveling" of the compression) occurs
much sooner than I expected. You will probably have noted that via my
recent posting to that effect, where I monitored file sizes after
repeated Jpeg compression.
It seems the algorithm rather rapidly reaches the point of "no further
benefit" and stabilizes the file size, and likely also the amount of
change in the pixel structure.
Bill Ross wrote:
> The only very slight disagreement I'd have is that it might be possible
> that if you open and save in JPEG format enough times, you might
> actually reach a point where you are "chasing your tail" and that
> certain random pixels will change one way one time and then return to
> the same position the next. However, by the time the process reached
> this point, it would seem you'd have such an abstraction of the
> original, it wouldn't much matter ;-)
> The ever-recurring discussion of whether jpeg is always
> lossy has become just such a cyclic abstraction to me.
> But that's life :-)
> Bill Ross