In article , Neil
wrote:

How is a 32-bit program going to manage a data block (with the document)
in memory that is over 4 GB in size? Yes, the program can, as you
implied, use a buffer to load part of the over 4 GB file into memory,
but, say, a search that scans the 4+ GB memory for the data block is
going to dump one buffer to move it into later bytes of the file. That
is for direct memory access to the file's contents.

The techniques used by professional graphics apps in the 1980s made the
size limitation of files based on disc size rather than memory.
PhotoStyler was one such app that only loaded the portion of the file
that filled the screen, and did so in a way that enabled detailed
editing on enlarged portions or viewing the full image at screen
resolution (which was minuscule by today's standards) without any
noticeable delay. After Adobe purchased PhotoStyler, mainly to eliminate
competition for PhotoShop which at the time was quite an inferior
product, they began integrating the programs methods and features into
PhotoShop. So, a 4GB file wouldn't be a problem.

quite a bit of revisionist history there.

photoshop implemented its own memory manager to handle larger images
before photostyler even existed due to the limitations of the hardware
at the time.

adobe purchased aldus for their entire portfolio, not specifically
photostyler, which wasn't in any way competition for photoshop.

I don't know where you're getting your information about any of this,
but it's clear that it's not from personal experience. OTOH, I made a
good living using these apps professionally and know what their
differences amounted to because it affected my work.

it's very much personal experience, going back to when photoshop was in
beta, long before photostyler even existed. i know people who worked on
photoshop as well as good friends with the owner of a company that
turned down the opportunity to publish it before adobe did. i've also
written several photoshop plug-ins and was intimately familiar with the
internals of photoshop.

your version of history does not match reality. it's as simple as that.

Photoshop had quite a few shortcomings in comparison to PhotoStyler,
such as its method of loading the full image into memory and a lack of
customizable settings.

rubbish. photoshop always had its own memory manager due to limitations
of 1980s era hardware, *before* photostyler even existed as a product.

claiming that adobe copied virtual memory from a non-existent product
is crazy-talk.

Yes, Adobe purchased Aldus to acquire PhotoStyler and PageMaker, but
their FIRST move was to take PhotoStyler off the market, and it was
definitely a competitive product.

the only advantage photostyler had was that it ran on windows before
photoshop, which began life as a mac-only product and was ported to
windows with version 2.5, well before adobe bought aldus.

since there was no reason to have two nearly identical products, adobe
eol'ed photostyler.

But, this thread isn't about
Photoshop, it's about image size limitations, and that was dealt with
effectively by several pro-level graphics apps at the time and could be
dealt with in the same manner today to allow editing of any size image.

this subthread is about the limitations of 32 bit apps.

Believe whatever you want or find in some google search.

no need, since i know exactly what happened and some of the people
involved.

perhaps you should talk to people who actually worked on photoshop,
although i doubt even that would convince you.