Hacker News Board Hacker News, browsed like a classic message board
Live data from Hacker News

Xerox responds to the recent character substitution issue

realbusinessatxerox.blogs.xerox.com

Post reply on HN
Print view View original

11–20 of 72 posts

Re: Xerox responds to the recent character substitution issue

#11

Post by xahrepap »

wtallis wrote: 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…

> We do not normally see a character substitution issue with the factory default settings however, the defect may be seen at lower quality and resolution settings.

I might have read it wrong, but from how I understood it the default settings don't have this problem. It's when people adjust the quality settings to be lower. Am I wrong?

Re: Xerox responds to the recent character substitution issue

#12

Post by [deleted] »

ToothlessJake wrote: post #9
hyborg787 wrote: post #6

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...

[deleted]

Re: Xerox responds to the recent character substitution issue

#13

Post by eksith »

"We do not normally see a character substitution issue with the factory default settings..."

It shouldn't be seen with any setting. Nothing you can do to the device (short of involving a hammer) should change the content in any way. Compress, resize, zoom, do whatever, but it simply must not change the content at any time at any resolution/quality.

I'm just flabbergasted that such a compression scheme was ever implemented in the first place. Surely, there are alternative OCR based methods do compression that don't introduce these artifacts (that's putting it mildly) at lower resolutions.

Re: Xerox responds to the recent character substitution issue

#14

Post by ToothlessJake »

hga wrote: post #10
ToothlessJake wrote: post #9

Earlier quoted context omitted.

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.

O-SubC-R then perhaps. Still is recognizing shapes/symbols which is the very basis of OCR.

This seems a bit hair splitty when the end result is the same as invalid OCR dictionaries.

Re: Xerox responds to the recent character substitution issue

#15

Post by quantumpotato_ »

jevinskie wrote: post #3
soulclap wrote: 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! =(

(OT: how do you downvote on HN?)

Re: Xerox responds to the recent character substitution issue

#16

Post by [deleted] »

ToothlessJake wrote: post #9
hyborg787 wrote: post #6

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...

[deleted]

Re: Xerox responds to the recent character substitution issue

#18

Post by eyeareque »

Sounds like the "recognized industry standard JBIG2 compressor" is just about useless for copy machines. Why even give a user the ability to do this?

The only acceptable fix for this is to disable the ability to use lower compression qualities that have could EVER cause this to happen.

Re: Xerox responds to the recent character substitution issue

#19

Post by dman »

eksith wrote: post #13

"We do not normally see a character substitution issue with the factory default settings..." It shouldn't be seen with any setting. Nothing you can do to the device (short of involving a hammer) should change the content in any way. Compress, resize, zoom, do whatever, but it simply must not change the content at any time at any resolution/quality. I'm just flabbergasted that such a compression scheme was ever implem…

So you only want non lossy compression as an option?

Re: Xerox responds to the recent character substitution issue

#20

Post by mark-r »

These are multi function devices meant to be used by many people. If someone in your office has need to make occasional scans that need to fit in an email, isn't it natural to assume they might configure the machine for maximum compression? Why should that setting affect copies?
Post reply on HN