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Errr, I didn't communicate clearly.

What I meant to say was that CCITT Group IV gave acceptable sizes for early-'90s computing power, CPU and disk, and something at or better than its level of lossless compression today should be even more acceptable.

And in light of this screwup, I suspect we'd agree that Xerox would have been better off to use lossless (well, after the scanning, as you point out, but then again no one was willing to pay for color) CCITT Group IV than overly clever lossy JBIG2.

"It could be TIFF, it could be PDF, it could be something an intern coded during coffee break."

It could be something a journeyman software engineer edging to expect coded in a Saturday afternoon in a very fast paced project; for me, 3 weeks on the "engine". And, oh my, I can't remember encoding endiness, except of course for the leading TIFF bytes. But I had a guy who knew this cold telling me what to do, he was the one who debugged all our raw compressed data problems bit by bit. And, yeah, it was an "Intel" little endian TIFF, and I think I recall the Kodak Powescans produced that (600 pound monsters that could scan 18 inches per second at 200 DPI).

Hmmm, at least back then, "TIFF" was the selling point, and, oh yeah, it's Group IV compressed (except of course when it wasn't, we once dealt with some weird enhanced Group III).

Of course they would have been better off with T.6, as Group 4 at least did not modify the image content. However especially with TIFF there are/were countless implementations of viewers, components, libraries and every single one of them had their own habits. Some would not regard endianess, some would assume payload endianess is the same as the TIFF, some did respect the Tag for byte order specific to the image. When I coded my first TIFF Library, I was around 14 and the most troublesome part of doing it was keeping myself from bashing my head against the next available wall due to stupidity of other people who thought interpreting a standard according to their wishes was ok, because there'd never be someone trying to display the images with a viewer different from theirs.

I don't know how deep you have dived into TIFF, but maybe you remember the TIFF6 Standard way of embedding JPEG. It was the biggest pain in the ass imaginable, having to parse JPEG files, splitting them and packaging it into different TIFF Tags. Before TTN2 and easy embedding of JPEG Images, everyone invented their own way of avoiding the standard. Some defined their own compression type, some used the standard compression type, but used it in a nonstandard way, ah, I'm starting to lose my hair again ;-)

Not that deeply, I only did B&W document imaging, and I think the last time I worked on TIFF headers and tags was in 1992, so it was almost certainly the 5.0 standard, 6.0 came out in that year.

And yeah, it was a mess; we mostly did the best we could and made sure the ones we generated worked for our customer's reader(s). Although I don't remember any big problems with people reading the ones we produced.

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