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Xerox responds to the recent character substitution issue

realbusinessatxerox.blogs.xerox.com

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Re: Xerox responds to the recent character substitution issue

#4
So they claim that the fine print warns about character substitution. But they still are willing to label the option with that problem "normal quality" and suggest using "high quality" to get strictly image compression applied with no OCR. They don't seem to understand that a photocopier should in its normal operating mode never do post-processing that creates such surprising and misleading artifacts - better illegible and obviously so than legible but incorrect.

Don't get me wrong - using OCR is a great compression technique, but if it isn't reliable enough, it shouldn't be the default or "normal" setting.

Re: Xerox responds to the recent character substitution issue

#5
post #2

Previous discussion: https://news.ycombinator.com/item?id=6156238 Follow-up blog post about a conference call with Xerox: http://www.dkriesel.com/en/blog/2013/0806_conference_call_wi...

Inadvertent downvote, I'm sorry! =(

Countered.

Re: Xerox responds to the recent character substitution issue

#6
post #4

So they claim that the fine print warns about character substitution. But they still are willing to label the option with that problem "normal quality" and suggest using "high quality" to get strictly image compression applied with no OCR. They don't seem to understand that a photocopier should in its normal operating mode never do post-processing that creates such surprising and misleading artifacts - better illegib…

This has nothing to do with OCR. It's an issue with the JBIG2 compression re-using similar patches as substitutes for certain areas of the images if they're "close enough". This issue is exacerbated at lower resolutions.

Re: Xerox responds to the recent character substitution issue

#7
post #4

So they claim that the fine print warns about character substitution. But they still are willing to label the option with that problem "normal quality" and suggest using "high quality" to get strictly image compression applied with no OCR. They don't seem to understand that a photocopier should in its normal operating mode never do post-processing that creates such surprising and misleading artifacts - better illegib…

There's no OCR involved here. None.

All it's doing is recognizing "similar" patches of the image and coalescing them, which is what it's supposed to do, according to the standard. Yes, it's too aggressive.

Re: Xerox responds to the recent character substitution issue

#8
post #7
post #4

So they claim that the fine print warns about character substitution. But they still are willing to label the option with that problem "normal quality" and suggest using "high quality" to get strictly image compression applied with no OCR. They don't seem to understand that a photocopier should in its normal operating mode never do post-processing that creates such surprising and misleading artifacts - better illegib…

There's no OCR involved here. None. All it's doing is recognizing "similar" patches of the image and coalescing them, which is what it's supposed to do, according to the standard. Yes, it's too aggressive.

The stated goal of JBIG2 is to recognize 'characters' on the fly and compress them together. It's not traditional OCR but I wouldn't take such a hard line.

Re: Xerox responds to the recent character substitution issue

#9
post #4

So they claim that the fine print warns about character substitution. But they still are willing to label the option with that problem "normal quality" and suggest using "high quality" to get strictly image compression applied with no OCR. They don't seem to understand that a photocopier should in its normal operating mode never do post-processing that creates such surprising and misleading artifacts - better illegib…

This has nothing to do with OCR. It's an issue with the JBIG2 compression re-using similar patches as substitutes for certain areas of the images if they're "close enough". This issue is exacerbated at lower resolutions.

Thats OCR...

Re: Xerox responds to the recent character substitution issue

#10

Earlier quoted context omitted.

This has nothing to do with OCR. It's an issue with the JBIG2 compression re-using similar patches as substitutes for certain areas of the images if they're "close enough". This issue is exacerbated at lower resolutions.

Thats OCR...

Well, it doesn't go all the way, at least in this implementation (contrary to Xerox's statement, we've been told compression is not standardized), to actually recognize the symbols it finds. If it did, it would presumably make many fewer of these errors, maybe almost none since when it's uncertain it could just go with the original.
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