There’s a lot to consider here, and I’m certainly encouraged by Adobe's long standing focus on consistent PDF view experiences. (At least compared to other formats)
That being said, this feels somewhat like Adobe will turn PDFs into a form of markdown where the parser is a (variable?) machine learning algorithm.
Done perfectly, the results could be great. Done badly and the results would be very painful.
Liquid mode? It looks like a tool to reflow the content in existing PDFs, which are often intentionally not responsive. I don't see how this is similar to HTML.
PDFs can do all sorts of voodoo (like you can do with HTML if you hate the user's browser) to make legible content that is pretty illegible to machines - but most documents are produced by tools that have pretty sane outputs that can be reverse parsed to get a pretty nice HTML blob.
Isn't the whole point of PDFs that they (mostly) don't change? They represent content as laid out on a page.
So, IMO this is neat if it's new tech for reading PDFs and extracting data from them (and maybe leveraging current under-used features to store more machine-readable information), but bad if it's about introducing even more complexity into the PDF documents.
Perhaps 10 years from now we will have responsive PDFs, but I feel sorry for whatever damned soul is going to have to expand hard-coded limits in order to fit the new PDF specification text into a single PDF document.
This is more like a readability mode than a responsive website.
It's a button you click to automatically make a fixed-layout PDF fluid and easier to read on mobile.
You'd still author the document the same way without considering multiple device sizes. When the PDF needs to be reproduced faithfully (printing) it would still appear as the creator intended.
It does not sound like the goal is device-dependent rendering, though. This is exactly parallel to Reader Mode, which is a temporary user toggle. The goal of PDF is still to produce documents that mirror print-ready layouts, something that HTML has never really accomplished. Whether you want to consume the documents that way will now be up to you.
It's not crazy to have a device-independent presentational document that also contains enough data to enable some device-dependent rendering of its text and media contents.
That would be the case if a PDF was solely used for print.
In the digital realm though, a PDF should also be accessible to screenreaders for the blind, people with sight problems (increased fonts, contrast), dyslexia, etc. Those already require alternative representations.
And of course nothing bad about having the best of both worlds! A format that is pixel perfect when you want it too, and adaptable for easier reading when you don't.
I read a boatload of 2 column PDFs on my phone. Liquid Mode has been on PDF Reader on Android for... it feels like a year now? And it's fantastic. Without it I have to constantly pinch and zoom and swipe to the upper right to start a new column, etc.
I hate PDFs, but if I want to read a document I've stored in print fidelity from the 80s on my phone, Liquid is rock solid.
Not OP. Xiaomi MIUI bundles WPS office, which has a "mobile view" for PDFs. It's far from perfect, but it can single-column some multi-column PDFs. Some PDFs, like restaurant PDFs are downright butchered though.
According to the article Adobe reader for Android got this feature recently. I tried it and I am disappointed. Maybe OP was talking about reflow mode that indeed was accessible in many pdf readers, but for technical papers (math) it was useless.
>It's a button you click to automatically make a fixed-layout PDF fluid and easier to read on mobile.
But this of course reminds us of the miserable UX we have come to accept from the "mobile web". In the beginning, mobile websites didn't exist, and you just zoomed. Now, it's practically impossible to view the desktop website from a phone at some URLs without jailbreaking your device (if it's iOS). The net effect has been a severe degradation of usability in the worst cases for a small improvement in aesthetics and speed in the best.
I truly hope that PDFs do not meet the same fate, and remain readable on mobile in the correct layout, with no in-document markers that force my iPhone to display it wrong. While that apparently hasn't been proposed here, I don't like even the risk of it being proposed.
About "responsive PDFs": there's already a "reflow" feature in Acrobat Reader. It's limited but kinda works on clean PDFs. I don't know to what extent it's a explicit possibility of the PDF standard.
When your digital document format needs artificial intelligence to understand the content, it may be the wrong container for delivering content. I'll be sad to see content that should be delivered as HTML instead delivered as liquid PDF.
According to this article, nothing will be "delivered" as liquid PDF, because it's a feature of the reader app, not the document.
The point is that there are 30 years worth of existing, static, PDF documents - published as PDF for a potentially valid reason - which are frustrating to read on a mobile device.
I'm not convinced this is even a feature of the reader app. When they click "Liquid Mode", it says "Processing in Document Cloud" which means they're sending all your PDFs to their servers? Make sure you don't click Liquid Mode on any sensitive documents!
The PR post states near its end that the more documents go through Adobe Sensei the better it will get. So yes, they’re mining third party data. It would be interesting to see if this is GDPR compliant (I bet no since user is not well informed about the processing).
> Christ, we need AI and ML to read a static document now
The article doesn't say that. This is like Reader Mode in your browser. It presents the same content in a different way based on an understanding of the document structure. You don't need to use it.
If you want content to be able to be presented in different ways (such as a Reader Mode) that reflect the document structure, there are far better options than PDF. This is Adobe trying to extend their moat. Just Say No.
You may as well be saying that there are better options for producing readable text than HTML, because that's what Reader Mode is for. Yes, but entirely irrelevant. Reader Mode is for the reader to use, not for the writer to use. Liquid Mode is for the reader to use, not for the writer to use. See the parallel?
What the writer wants to present is structured layout based on design. Sometimes that's what the reader wants to see, other times not. That's why websites aren't all flat text and browsers have reader modes, not the other way around.
HTML is not known for providing print-ready layouts. This is just a different way of viewing documents that are designed to be print-ready. Whether they choose to implement the output of the conversion in HTML or some other method isn't relevant to the announcement.
I remember they had something similar 15 years ago. It was called tagged PDFs. It was useful on low resolution devices like PocketPC as the full page view wasn't readable. You had to convert your PDFs before loading them onto the device. Probably went out of favour when the iPhone came along and screen resolution increased. Looks like it’s an upgraded version of this with added ML.
Tagged pdfs are still a thing for accessibility, to make pdfs work better with assistive technology. In practice, this is underutilized, because of the additional effort to use it properly.
A better title would be an ”ambitious multi-year vision for Adobe Reader” as this isn’t changing the PDF format at all: it is simply a new, buzzword-compliant (AI! ML!) content-reflowing UI for the reader app.
Agreed. It seems that a lot of people aren't getting past the title, so now there are a bunch of misguided comments peppered all over the thread about needing to use AI to read PDFs, which is definitely not what the announcement is saying.
I disagree - this is just a change in the reader but it cascades into format changes.
I don't know if you've ever had the fun of writing a website using bootstrap and then having a client complain that the page layout changes (i.e. becomes responsive) when the window is resized. I've hit that a few times with things that need to go through audits/agency approvals and in those cases you can pull out some of the @media tags and call it a day.
Imagine having to make sure that liquid mode won't reflow a document that was signed off on by the FDA because there's a concern that the ISI (important safety instructions) box required to occupy 10% of real estate on that page might be shrunk to occupy 5%.
I agree this announcement is a lot less disruptive than the statement initially makes it look, but it's still going to have knock on effects.
Content reflowing isn't easy for pdf files. Xodo has this functionality for years and it rarely get the line break right, so there is some use for ML in this. (Or do you happen to know a pdf reader that is better in this?)
It sounds like it will make viewing papers and such that are PDFs much more convenient, eventually.
But it really makes you question the idea of putting things into PDF format in the first place.
Because at this point it may be that a significant majority of the time PDFs are read on screens.
So in my opinion it might make more sense for acedemic journals (for example) to standardize on a something like reStructuredText (which now supports LaTeX by default). Or maybe Markdown, or a subset of HTML.
Or maybe a standard eReader (Kindle-like) format.
Or just default to a tar.gz with the RST and supporting files in standard folders.
Then if they want to publish a print journal they can automatically format it for printing. If it doesn't look good enough sometimes then let the print journals use AI or manually typeset it (earn their money).
So anyway I wish Chrome and Firefox would get support for my new RST archive format.
Point being that PDF is getting a little obsolete.
Its not broken, its just abused. PDF is create for printing, its not great for anything smaller than an A4 page. Other formats exist which do that fine. If you use pdf for what it was made for its fine.
Is everyone in such a rush to comment that they don't even bother to RTFA? A majority of the comments here are knee-jerk reactions to a headline that was misunderstood...smh.
Liquid mode is simply a tool to make it easier to consume PDF content on mobile devices. This is definitely a good thing especially since it is opt-in (you press a button to engage liquid mode in the reader).
The problem is that PDF has already had a few cycles of adding and then shedding off useless, and frankly, dangerous ideas because they keep trying fit a square peg in a round hole.
That may be, but it still has no real relevance to this article unless people just want any excuse to get on their soapbox to rant about Adobe/PDF without even bothering to read the article and what it is talking about.
Exactly, and this feature could encourage more people to use PDFs in context where they should not really be used, because of having a false sense of security that their document will somehow magically be reflowed on devices that it wasn't authored to display on.
Eh, I don't like 2D scrolling, it is a lot more of a pain then 1D scrolling - so I think it's a valid problem to try and resolve. That said I also think PDFs are just conceptually broken when it comes to mobile devices - you specifically don't want single format files on that device and, often times, you don't need to consume them on mobile.
It seems to work well to me so I don't know what you mean by conceptually broken or single format files. Having a single file that you can zoom in and out on was one of the original multi-touch demos in the TED talk, years before the iphone.
I'm also not sure why they are different from anything else when it comes to 'needing to consume them on mobile'.
I agree, my 12.9" touch screen is the best device for reading PDFs I could imagine. A ReMarkable is at least as good for black and white (I've tried it) but a lot of PDFs are full color.
PDF on a phone is unremitting pain. I'd rather muddle through on a laptop. I'll give this this a shot, it might help, and it can't hurt, since it's just a button you can push that says "make this thing legible, maybe".
I'm especially enraged at the PDF "forms" XFA or whatever that no software on this planet can open except Adobe Reader. And Adobe Reader even on macOS doesn't allow Print to PDF or something else to get a PDF in a "sane" format.
I have to use a fake printer to trick Adobe Reader about this! Incredible!
Fun loophole that usually works--so Adobe Acrobat on the Mac doesn't let you use the default Print to PDF functionality, BUT if instead of selecting PDF you print to Postscript it will work.
Speaking of print-to-PDF, this is tremendously useful functionality, but fails on over half of the web pages out there. Is this due to some intentional action by the publisher, as a copy protection mechanism, or due to faults in the print-to-PDF driver? If due to faults in the driver, whose print-to-PDF driver is the best at implementing this functionality - I've tried several and they all seem to be sub-par.
Another PDF issue, does anyone except Adobe make a good PDF malware remover (from inside the PDF file). PDF malware seems to be rare, but could be a big problem if it ever catches on.
Dear god please no. PDFs suck, but they're the only viable medium for scientific publication, and they aren't "broken" for that. Do not fuck them up with your proprietary crap, Adobe.
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[ 3.0 ms ] story [ 182 ms ] threadThat being said, this feels somewhat like Adobe will turn PDFs into a form of markdown where the parser is a (variable?) machine learning algorithm.
Done perfectly, the results could be great. Done badly and the results would be very painful.
Sounds like a way to extend vendor lock-in, as nobody else will be able to implement the same algorithm with any assurance of interoperability.
Better have an alternative that is controlled by one company. Shareholders like that. Think social media, ads, apps.
So, IMO this is neat if it's new tech for reading PDFs and extracting data from them (and maybe leveraging current under-used features to store more machine-readable information), but bad if it's about introducing even more complexity into the PDF documents.
Perhaps 10 years from now we will have responsive PDFs, but I feel sorry for whatever damned soul is going to have to expand hard-coded limits in order to fit the new PDF specification text into a single PDF document.
It's a button you click to automatically make a fixed-layout PDF fluid and easier to read on mobile.
You'd still author the document the same way without considering multiple device sizes. When the PDF needs to be reproduced faithfully (printing) it would still appear as the creator intended.
https://en.wikipedia.org/wiki/Comparison_of_e-book_formats
(spoiler, most of them are HTML/CSS)
Epub is HTML and CSS bundled in a zip file following a specific directory tree layout and containing a few metadata files.
Epub 3 is HTML5.
Open LibreOffice, create a doc, save it as Epub, and unzip the file. See for yourself.
It does not sound like the goal is device-dependent rendering, though. This is exactly parallel to Reader Mode, which is a temporary user toggle. The goal of PDF is still to produce documents that mirror print-ready layouts, something that HTML has never really accomplished. Whether you want to consume the documents that way will now be up to you.
In the digital realm though, a PDF should also be accessible to screenreaders for the blind, people with sight problems (increased fonts, contrast), dyslexia, etc. Those already require alternative representations.
And of course nothing bad about having the best of both worlds! A format that is pixel perfect when you want it too, and adaptable for easier reading when you don't.
I hate PDFs, but if I want to read a document I've stored in print fidelity from the 80s on my phone, Liquid is rock solid.
Say that to those who create PDF files for things that should be web pages. That behavior is not going to stop anytime soon.
But this of course reminds us of the miserable UX we have come to accept from the "mobile web". In the beginning, mobile websites didn't exist, and you just zoomed. Now, it's practically impossible to view the desktop website from a phone at some URLs without jailbreaking your device (if it's iOS). The net effect has been a severe degradation of usability in the worst cases for a small improvement in aesthetics and speed in the best.
I truly hope that PDFs do not meet the same fate, and remain readable on mobile in the correct layout, with no in-document markers that force my iPhone to display it wrong. While that apparently hasn't been proposed here, I don't like even the risk of it being proposed.
Maybe put a link on the pdf for online ordering or finding locations, but I have no idea why the home page should be anything but a menu.
https://helpx.adobe.com/acrobat/using/reading-pdfs-reflow-ac...
The point is that there are 30 years worth of existing, static, PDF documents - published as PDF for a potentially valid reason - which are frustrating to read on a mobile device.
A frictionless solution would be for Adobe to offer the AI as a web service that renders legacy PDF files as HTML.
I laugh now as I laughed back then.
The article doesn't say that. This is like Reader Mode in your browser. It presents the same content in a different way based on an understanding of the document structure. You don't need to use it.
What the writer wants to present is structured layout based on design. Sometimes that's what the reader wants to see, other times not. That's why websites aren't all flat text and browsers have reader modes, not the other way around.
To me it reads like this adds absolutely nothing to that which HTML has been already delivering for years.
I’m very skeptical but somehow intrigued.
They should start with a better prediction of the zoom level and single/continuous page rendering modes when opening a PDF document.
I don't know if you've ever had the fun of writing a website using bootstrap and then having a client complain that the page layout changes (i.e. becomes responsive) when the window is resized. I've hit that a few times with things that need to go through audits/agency approvals and in those cases you can pull out some of the @media tags and call it a day.
Imagine having to make sure that liquid mode won't reflow a document that was signed off on by the FDA because there's a concern that the ISI (important safety instructions) box required to occupy 10% of real estate on that page might be shrunk to occupy 5%.
I agree this announcement is a lot less disruptive than the statement initially makes it look, but it's still going to have knock on effects.
But it really makes you question the idea of putting things into PDF format in the first place.
Because at this point it may be that a significant majority of the time PDFs are read on screens.
So in my opinion it might make more sense for acedemic journals (for example) to standardize on a something like reStructuredText (which now supports LaTeX by default). Or maybe Markdown, or a subset of HTML.
Or maybe a standard eReader (Kindle-like) format.
Or just default to a tar.gz with the RST and supporting files in standard folders.
Then if they want to publish a print journal they can automatically format it for printing. If it doesn't look good enough sometimes then let the print journals use AI or manually typeset it (earn their money).
So anyway I wish Chrome and Firefox would get support for my new RST archive format.
Point being that PDF is getting a little obsolete.
A pdf file is a program that outputs pages you can display or print. There are no more restrictions to the format.
That’s why without some artificial intelligence you can’t edit or reflow the contents.
Where are the changes to the PDF format that will help other viewers understand hierarchy and relayout pages without Adobe's ML engine?
Liquid mode is simply a tool to make it easier to consume PDF content on mobile devices. This is definitely a good thing especially since it is opt-in (you press a button to engage liquid mode in the reader).
Of course, it's Adobe's reader. So the chances that this will lead to even more mucking about with the format are pretty high.
Which hey, for me that's job security. Which is not to say I look forward to it...
But Liquid Mode, now with more machine learning, isn't those changes. It's just reader mode for PDF.
I'm also not sure why they are different from anything else when it comes to 'needing to consume them on mobile'.
PDF on a phone is unremitting pain. I'd rather muddle through on a laptop. I'll give this this a shot, it might help, and it can't hurt, since it's just a button you can push that says "make this thing legible, maybe".
I'm especially enraged at the PDF "forms" XFA or whatever that no software on this planet can open except Adobe Reader. And Adobe Reader even on macOS doesn't allow Print to PDF or something else to get a PDF in a "sane" format.
I have to use a fake printer to trick Adobe Reader about this! Incredible!
Another PDF issue, does anyone except Adobe make a good PDF malware remover (from inside the PDF file). PDF malware seems to be rare, but could be a big problem if it ever catches on.
> Saving a PDF file when printing is not supported. Instead, > choose File > Save.
Because Adobe went out of their way to prevent this to work.
It is nice though.
I do agree it's disappointing that they can't just process it locally though.