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Preview in macOS Big Sur is destroying PDFs

annoying.technology

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Re: Preview in macOS Big Sur is destroying PDFs

#91

Post by zepto »

db48x wrote: post #34
zepto wrote: post #2

They are using software unsupported by the vendor and blaming Apple for the outcome. “ABBYY says they don’t support Big Sur yet, that’s fine. But Apple didn’t tell me that I can’t upgrade to Big Sur when I use ABBYY. I’d be a lot less angry if there was a changelog or release notes from Apple where it says there is a known problem with OCR’ed PDFs in Preview. Their software is broken, they need to tell me. I don’t ca…

Are you arguing that ABBYY Finereader is going to produce different PDF files once they support the new OS? Possibly they will, if only to work around this obvious bug in Preview.

I’m arguing that yes, they will produce different PDF files.

It’s not obvious the bug is in preview. The bug could easily be in in ABBYY’s PDF generation code.

To be fair, I’m not arguing that this is the case. I’m arguing that it just as easily could be as there being a bug in Preview, which is also possible.

Re: Preview in macOS Big Sur is destroying PDFs

#92

Post by rbanffy »

fastball wrote: post #51
lisper wrote: post #46

Using Apple devices in general seems like a total crap shoot to me nowadays because of the impossibility of down-grading the OS. Every "upgrade" comes with a considerable risk that something that had been working will stop working, and if that happens, you are pretty much SOL.

What? You can definitely downgrade to an earlier MacOS. It's not a one-click downgrade like the upgrade is, but I don't know of any OS with that feature.

> What? You can definitely downgrade to an earlier MacOS.

Unless they got a brand-new M1-based Mac. Macs usually don't install versions of macOS prior to their launches.

Re: Preview in macOS Big Sur is destroying PDFs

#93

Post by jrochkind1 »

xxpor wrote: post #21

Why anyone treats PDF as anything but a write-once format is beyond me. It's so finicky that I'm not shocked bugs like this happen. The only programs I'd be reasonable sure wouldn't screw it up are Acrobat itself, and pdflatex and friends. I think we need a multi-image container format. It could be something that's literally a bunch of jpgs/pngs/pick your poison in a tar container, and given a new extension. OSes wou…

Making a PDF include OCR'd text seems to by definition require writing twice. It has to be edited to add the OCR'd text that was not in the original image-only PDF, no?

I mean, you can say that the second PDF is a different PDF that has only been written once, but you can say that about literally any edit, "write once" no longer means anything if you think about it that way.

Re: Preview in macOS Big Sur is destroying PDFs

#94

Post by crazygringo »

inetknght wrote: post #82
crazygringo wrote: post #27

I work with a ton of PDF's between my Mac and iPad, and it mostly works but there are still just way too many bugs. It's a lot of little things, like in Catalina where opening up the sidebar for annotations (comments) seemingly randomized their order. (Big Sur, fortunately, fixed it to be page-order again.) Or how printing a PDF from a website (in Catalina, also seemingly fixed in Big Sur) would look right on the pag…

> 10% of the glyphs were scrambled ("lik3 thZs"), like some sort of character table corruption. As I understand it, that's a form copy protection trying to prevent exactly what you're doing.

While that type of copy-protection does exist in rare instances, in this case it wasn't -- it was with any normal webpage printed to PDF. It was a straight-up bug, I tried to file it with Chromium in fact [1], but it turned out to be a macOS issue that Big Sur fixed.

[1] https://bugs.chromium.org/p/chromium/issues/detail?id=112849...

Re: Preview in macOS Big Sur is destroying PDFs

#95

Post by mynameisvlad »

zepto wrote: post #70
arvindamirtaa wrote: post #38

Earlier quoted context omitted.

I receive that PDF file that looks like any other PDF file. I open it with preview. It opens fine. I close it and open it again. It opens fine. I open it a third time and make a small arrow pointing to something and save it (as I would with ANY OTHER PDF). It breaks. I'm not using ABBYY. I've never heard of it. It's not on my system. It's just a PDF file that I got sent. Now what?

You’re a victim of ABBYY’s poor PDF generation, that’s what. Nothing excuses ABBYY if their PDFs are corrupt.

Wow, just wow.

The PDF works fine before saving in Preview. As in, Preview itself will render the file perfectly fine with OCR. By all accounts, the PDF is completely valid and uncorrupted at this point. Making a change to the file and saving it in Preview is what causes the corruption.

So how the hell could you possibly excuse Preview and call this a ABBYY issue when Preview is the one that causes the issue?

That's absurd to the highest level.

Re: Preview in macOS Big Sur is destroying PDFs

#96

Post by jcrawfordor »

zepto wrote: post #65
jcrawfordor wrote: post #26

Earlier quoted context omitted.

So Preview opens a file, which is apparently valid per Preview (Preview handles and displays it correctly). After changes, preview then saves a file that is not valid per Preview (OCR text layer is corrupted). It is very difficult for me construe a situation in which this would not be considered errata in Preview. Even if ABBYY is writing unusual PDFs, it's popular enough software that this issue will be encountered…

“The idea that this behavior in a PDF reader can be excused because the software that generated the PDF was not approved for the operating system the viewer is running on per the vendor.” Nobody is saying that. The suggestion is that the software that generates the PDF produces corrupt documents. The fact that the vendor of that software doesn’t approve it for Big Sur suggests that they might be aware that there are…

I worded it that way for two reasons, one of which is admittedly speculative:

1) It seems highly unlikely that ABBYY relies on some changed OS behavior in generating PDFs that leads to it producing PDFs that are malformed in such a way that is only revealed when they are rewritten by Preview. Behavior in Preview is by far a more likely cause of the problem. Generally the thing that changed is what broke...

2) To the user, this looks 100% like a problem in Preview no matter what's happening, and it's Apple's responsibility to not do this kind of thing to users. The PDF opens properly the first time, so de facto it is "valid" as determined by the product that later corrupts it. As I said, handling questionably valid PDFs is part and parcel of writing PDF software, and failure to handle a PDF that otherwise renders correctly looks like a bug on your part... especially when it otherwise renders correctly in your own software.

Re: Preview in macOS Big Sur is destroying PDFs

#97

Post by Aperocky »

lilyball wrote: post #64
birdyrooster wrote: post #41

Earlier quoted context omitted.

Did they save the file using Preview? If so that’s on them, they chose to write a pdf using Preview and that comes with all of the pitfalls of pdf compatibility. Does plain old PostScript have this problem?

Yes, they used Preview to modify the PDF.

So misleading.

There are a chance that write goes wrong, but Preview is much more geared towards read than write.

This doesn't excuse Preview, but its name is suggestive enough.

Re: Preview in macOS Big Sur is destroying PDFs

#98

Post by fastball »

From what I can tell, there is no reason you can't just run the PDF through ABBYY FineReader again and get the exact same OCR you got the first time, so I think "irreversible" is a bit over-the-top.

Is it as easy as CMD+Z? No. Is it data you can never get back? Also no.

Re: Preview in macOS Big Sur is destroying PDFs

#99

Post by arvindamirtaa »

zepto wrote: post #89
arvindamirtaa wrote: post #77

Earlier quoted context omitted.

Hahaha this is just brilliant.

It’s not brilliant. It’s just correct if ABBYY is producing corrupt PDFs, which is a possible cause of this problem.

If "Corrupt" = works fine until you make an edit and save using Preview, yes. You're 100% correct.

Re: Preview in macOS Big Sur is destroying PDFs

#100

Post by hcurtiss »

systemvoltage wrote: post #36
xxpor wrote: post #21

Why anyone treats PDF as anything but a write-once format is beyond me. It's so finicky that I'm not shocked bugs like this happen. The only programs I'd be reasonable sure wouldn't screw it up are Acrobat itself, and pdflatex and friends. I think we need a multi-image container format. It could be something that's literally a bunch of jpgs/pngs/pick your poison in a tar container, and given a new extension. OSes wou…

PDF is one of the best things IMO - it's like a docker container for documents. The way the original authors intended it to be, including fonts and all the things that go into making a document. For example, I personally like to purchase books that are in PDF format, not epub/mobi. I want to rely on professional typesetting from the publishers, not some front-end engineer's vision of what the ebook should look like a…

I agree completely. Have you found any good resources for acquiring books in pdf?
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