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Dead Link[edit]

Link to "JBIG2 primer" seems to be dead, should it be replaced by ?

Major flaw of article: no talk about file formats[edit]

It is just briefly noted that pdf files "may contain JBIG2 compressed data". But other than that, the reader of this article is left clueless as to what other file formats support JBIG2 and if there is something like a native file format for JBIG2. And - on the contrary - if pdf is currently the only file format that can be used to store jbig2 compressed data, then it would be very helpful for the reader to mention that fact as well. --boarders paradise (talk) 13:28, 6 September 2009 (UTC)

Removed "Disadvantages" section[edit]

I removed the "Disadvantages" section. While it was well written and had a citation, it does not belong on this page. The description of the edit was "Algorithm can cause corruption of text" which is true of all lossy compression algorithms. But the section about how such corruption could cause incorrect dosages of medicine to be delivered sounded like a bad TV news headline. One could say the same about any kind of data corruption. It could also cause nuclear plants to melt down. If someone applied OCR to a lossy compressed image, then used that to give a dosage of medicine - that would be a worthy news headline -- but not a worthy Wikipedia article.

Last comment -- Just because you read it on Slashdot doesn't mean you should put it on Wikipedia. — Preceding unsigned comment added by (talk) 13:48, 6 August 2013 (UTC)

Your edit is vandalism section-blanking and has deleted valid information. JBIG2 is not the same as "all lossy compression algorithms". JPEG blurs things; it doesn't put characters through OCR and inadvertently replace a few of them with different characters to alter the meaning of text. Key distinction, and all properly sourced to WP:RS. Furthermore, you attempted to remove the entire section, not just the one mention of transmitting medical information. Please do not remove valid, sourced information from articles. K7L (talk) 13:57, 6 August 2013 (UTC)
Do not accuse people acting in good faith of "vandalism", see WP:NOTVAND. Clearly OP here had good intentions, (s)he even bothered to write up a rationale for the removal.
I agree that this fact should be kept, but I decided to rewrite it. I clarified that this only happens in JBIG2 "lossy" compression mode and removed the synethsis about "structures being built not to specification or incorrect dosage". Do you think this is better? -- intgr [talk] 15:46, 6 August 2013 (UTC)
Yes, much better. The blueprints with the wrong numbers weren't WP:OR or synthesis as that is in the Beeb piece, but the key point is that OCR can replace one textual character with a different character, altering the meaning of documents. That is a serious limitation of using such an aggressive approach to data compression and needs to be in the article. K7L (talk) 15:51, 6 August 2013 (UTC)
I did keep this in the last sentence: "where numbers written on blueprints were altered". I think the original statement "consequences such as structures being built not to specification" is a bit much -- in this case that didn't happen as the corruption was discovered.
Do you want to suggest another way to phrase it? -- intgr [talk] 16:04, 6 August 2013 (UTC)
This looks good. K7L (talk) 16:08, 6 August 2013 (UTC)
I was the anon who removed it. The new one is well written and addresses my concerns. Sorry if I was overzealous. — Preceding unsigned comment added by (talk) 14:37, 10 August 2013 (UTC)
Unfortunately, the text was confused: David Kriesel clearly says that it was noticed in a construction document then found to occur elsewhere, but no specific correlation to document types other than all examples shown are of number substitution. Specifically, “the issue gets even more dangerous if life-important documents are scanned, like medical prescriptions” does not imply that copying of such has been tested, only that it is believed possible that they could be altered as described, with speculation about the effects.
Regarding consequences of incorrect blueprints – I think that it is likely that errors will be detected, although when is uncertain and there is potential for extra materials and/or transport costs to be incurred. Also, what happens if the errors happen such that the resulting document is internally consistent? Dsalt (talk) 14:43, 11 August 2013 (UTC)
I agree, I would remove the speculation about medical documents entirely, but somehow it always finds its way back into the article. -- intgr [talk] 07:34, 12 August 2013 (UTC)