12 ms·

No-cost access to the latest PDF standard: ISO 32000-2 (PDF 2.0)

187 points by MrRadar 4y ago

plq 4y ago
So I'm supposed to have a PDF reader to implement a PDF reader? What's the bootstrapping strategy here? tsk.
- LegionMammal978 4y ago
  > What's the bootstrapping strategy here? You open it in Adobe™ Acrobat™ Reader, of course. The first version of the PDF Reference Manual was published to accompany the first version of Acrobat™ [0]. [0] https://opensource.adobe.com/dc-acrobat-sdk-docs/pdfstandards/pdfreference1.0.pdf https://opensource.adobe.com/dc-acrobat-sdk-docs/pdfstandard...
sennight 4y ago
Heads-up: apparently some kind of signup is required to download anything from this page. So if you heartily dislike ISOs not because of cost, but because of how insane it is to make standards difficult to actually access at all - nothing has changed.
- deleted 4y ago
  [deleted]
btown 4y ago
It's worth noting that while https://www.pdfa.org/resource/iso-32000-pdf/ https://www.pdfa.org/resource/iso-32000-pdf/ mentions the 2011 patent release for PDF 1.7 (https://www.adobe.com/pdf/pdfs/ISO32000-1PublicPatentLicense.pdf https://www.adobe.com/pdf/pdfs/ISO32000-1PublicPatentLicense...) it makes no such mention of such a release for PDF 2.0. Additionally, https://www.pdfa-inc.org/eula/ https://www.pdfa-inc.org/eula/ seems to indicate that you may only use the downloaded files on one computer - and does not establish a license agreement between the user and any third party IP holders. No-cost access does not mean free-as-in-software. Caveat emptor.
- LegionMammal978 4y ago
  Formally speaking, I'm pretty sure you can satisfy the terms of the EULA by "buying" another copy of the files (another instance of the "Product") for every computer you want to store it on. IANAL though. (And regardless, it definitely doesn't meet the principles of freedom as in free software.)
dawidpotocki 4y ago
> ISO 32000-2 was also, however, the first and only core PDF specification published exclusively — and only for purchase — by ISO, inhibiting its use and adoption over the last five years. Who would have thought that "international standards" that require payment don't work well? How many people are willing to spend a couple hundred CHFs to access the PDF specs? Also it seems insane to me that the PDF creator, Adobe, now has to pay ANSI to distribute their own spec for free. For some reason you still need to "add to cart" the standards and they will ask you for your address and email. You don't need to provide real information for anything, not even email, they just redirect you to a page with download links. Also the EULA is insane. > You may install one copy of the Product on, and permit access to it by, a single computer owned, leased or otherwise controlled by you. In the event that computer becomes dysfunctional, such that you are unable to access the Product, you may transfer the Product to another computer, provided that the Product is removed from the computer from which it is transferred and the use of the Product on the replacement computer otherwise complies with the terms of this Agreement. Neither concurrent use on two or more computers nor use in a local area network or other network is permitted. You may print one copy of the Product for your personal use. You shall not merge, adapt, translate, modify, rent, lease, sell, sublicense, assign or otherwise transfer any of the Product, or remove any proprietary notice or label appearing on any of the Product. You may make one (1) copy the Product for backup purposes only. They don't even allow you to use it on your 2 devices at the same time. Complete nonsense that I'm sure everyone will follow.
- vasco 4y ago
  When nobody tells lawyers no, this is what happens. This protects nobody other than some lawyers feeling fuzzy that they "mitigated risks" for their customer.
  - anticensor 4y ago
    What if they are not allowed to say no to lawyers?
    - sennight 4y ago
LegionMammal978 4y ago
One interesting thing I noticed is that the shortest conforming PDF 2.0 file clocks in at 254 bytes long (if you strip out the indentation): %PDF-2.0 1 0 obj<</Count 0/Kids[]/Type/Pages>>endobj 2 0 obj<</Pages 1 0 R/Type/Catalog>>endobj xref 0 3 0000000000 65535 f 0000000009 00000 n 0000000053 00000 n trailer<</ID[( )( )]/Root 2 0 R/Size 3>> startxref 96 %%EOF This is 41 bytes longer than the shortest conforming file in PDF 1.0 through PDF 1.7, which do not require the ID entry in the file trailer dictionary. (Apart from the ID entry and file header, the shortest file is otherwise identical.) The standard justifies its mandatory inclusion by saying that "some workflows" require PDF files to be "uniquely identified". I wonder what sort of workflows those might be.
- popcorncowboy 4y ago
  DRM fingerprinting
  - LegionMammal978 4y ago
    At least the standard doesn't seem to support that: it suggests creating the ID by hashing the current time, file path, and file size. Besides, there are a billion other side channels that can be used to digitally watermark PDFs. Anyway, I've since found an explanation in the PDF 1.7 spec. PDF files can include "file specifications" (file paths or URLs) to refer to other files. An ID can be added to a file specification for an external PDF, which the PDF reader can validate against the ID contained in the located file's trailer dictionary, to ensure that the external PDF is the expected one. I guess "some workflows" must have gotten upset when trying to generate a link to a PDF file with no ID, so they finally required its presence in the spec.
ShadowBanThis01 4y ago
Nothing encumbered by fees or patents should be accepted as a "standard." Period.
- legulere 4y ago
  The problem is that work on standards costs a lot of money. Somehow we need to pay for that. The solution could be the state.
  - kajaktum 4y ago
    Like what? And if they do, is it really sustainable? Are these standard organisations really funded by the papers they sell?
    - justeleblanc 4y ago
      ISO is funded by sales and membership fees from member states. It's been around for 75 years. If they're not sustainable, I don't know what organizations are.
  - ajsnigrutin 4y ago
    But what is a standard? Either one company or multiple companies wanting to be interoperable with their software decide on a way to save data (communicate, whatever), so more people buy their software and use their prouducts. Adobe has an interest for more and more people to use PDFs because more people will then buy their products.. if they're afraid of the costs, don't publish the standard and risk people switching to other stanards.
  - johannes1234321 4y ago
    The fun is: The fees for obtaining the standard doesn't really go to the ones who create the standard. Standard is created by volunteers typically sponsored by their employer to go to standards meetings, who also pay (depending on national body) for being members.
    - 4y ago
GoblinSlayer 4y ago
Or just write plaintext documents IETF style.
- chrismorgan 4y ago
  IETF RFCs haven’t been plain text for quite some years. RFC 2629 (June 1999) defined the first XML vocabulary, and RFC 7990 (December 2016) completed the process of declaring an XML format the canonical source, rather than plain text. To learn more, start at https://www.rfc-editor.org/rse/format-faq/ https://www.rfc-editor.org/rse/format-faq/.
  - Karunamon 4y ago
    That's just for ease of translation into other formats, right? No human is reading/implementing the XML.
    - chrismorgan 4y ago
      I don’t know altogether. I know it’s common to author in something else and then convert into the canonical XML form, but I’d be surprised if it wasn’t also common to author in the XML format. It’s not an onerous format.
Sephr 4y ago
No cost... except a ton of your personal info.
- cbg0 4y ago
  You can lie on the Internet.
Titan2189 4y ago
Unsure how long it'll be valid, but to save you having to enter fake details, here you go: https://www.pdfa-inc.org/?download_file=2009&order=wc_order_UEpidrGCqkJ2Z&uid=0c7e6a405862e402eb76a70f8a26fc732d07c32931e9fae9ab1582911d2e8a3b&key=731a8741-5998-4a59-a37b-e24b0316f765 https://www.pdfa-inc.org/?download_file=2009&order=wc_order_...
- _a9 4y ago
  Thanks, popped into archive.org too https://web.archive.org/web/20230406111824/https://www.pdfa-inc.org/?download_file=2009&order=wc_order_UEpidrGCqkJ2Z&uid=0c7e6a405862e402eb76a70f8a26fc732d07c32931e9fae9ab1582911d2e8a3b&key=731a8741-5998-4a59-a37b-e24b0316f765 https://web.archive.org/web/20230406111824/https://www.pdfa-...
chrisshroba 4y ago
The discussion around this being a non-free standard encumbered with license restrictions makes me wonder: is there an alternative for pixel-perfect rich document rendering? HTML needs sandboxing to be safe, rtf is barebones, and .docx has external dependencies.
- herodotus 4y ago
  I worked on PDF for years, and yearned for a better way to render pixel perfect. I think that handling of lines, shapes and images could be drastically simpler, but, alas, handling Glyphs (characters/fonts) will always be a nightmare of complexity.
- wongarsu 4y ago
  The obvious example would be PostScript. After all, PDF grew out of a desire to have a postscript variant better suited for digital documents instead of just printing. Illustrator's file format (.ai) was also just postscript up to version 8 or so.
- nayuki 4y ago
  If you're describing an image format where all subobjects are bitmaps and not vectors, and all math is done with integers, then pixel perfection is possible. Once you introduce any mildly interesting vector or typesetting feature, you will not get pixel perfection. Examples: * You want to draw a circle. Antialiasing is desirable because jaggies look really ugly. Do you want to prescribe the exact antialiasing algorithm? What about other ones that are faster or more accurate? Which AA convolution kernel are you using - box, Gaussian, sinc? * Which approximation algorithm will you use to draw cubic Bézier curves? I don't think there is a closed-form solution for them. * You support affine transformations. Define a 10×10 square. Scale it by 1/100. Scale it by 100. What if, due to floating-point rounding errors, your square is now 9.999×9.999 and now renders to 9×9 pixels without antialiasing? * You support automatic text wrapping. One renderer uses float32, looks at how wide each word is, and decides to break at some point in the sentence. Another renderer uses float64, looks at how wide each word is, and decides to break at a different point in the sentence.
- layer8 4y ago
xtiansimon 4y ago
Half-joking—-Does the standard explain why some documents I open in Acrobat Reader ask me if I want to save, when I only opened the file (and made no intentional edits)??
- planede 4y ago
  PDF includes javascript as an extension, although I don't know if javascript actions can be triggered without user input or not. Also many PDF viewers have little to no support to javascript in PDF.
- layer8 4y ago
  This can happen for PDFs that are broken in some way and that Acrobat auto-repairs, and thus regards as modified. And no, the standard doesn’t concern itself with that particular behavior. Also, many PDFs “in the wild” do not fully conform to the standard, because Acrobat Reader is so lenient.
makkesk8 4y ago
The way pdf has become a standard in everyday life is truly disgusting. One is expected nowadays to have a pdf reader installed on your device, this is a problem in it self because most of the software short of just reading the pdf, that are "free" does not include most of the features one would come to expect to utilize the standard. Now I don't have to sign pdf's daily but when you start a new job for instance and have to sign a pdf it becomes troublesome. As a developer the ecosystem is pretty terrible too, in order to utilize said functions such as signing you'd need to fork out a huge chunk for a subscription to some library. Don't get me wrong, paying for software I'm all for but forcing your users to pay for some third-party software to interact with your documents is not fine. To me, this is simply disgusting that you'd have to buy into this "standard" in every aspect, both as a user and as a developer. We've come a long way over the years of having more options to both users and developers but honestly, it's simply not enough. And pdf as a format being very complex it's more than understandable that it would be a challenge to make it more available.
mindyhausler 4y ago
[dead]

187 points by MrRadar 4y ago

plq 4y ago

So I'm supposed to have a PDF reader to implement a PDF reader? What's the bootstrapping strategy here? tsk.

LegionMammal978 4y ago
> What's the bootstrapping strategy here? You open it in Adobe™ Acrobat™ Reader, of course. The first version of the PDF Reference Manual was published to accompany the first version of Acrobat™ [0]. [0] https://opensource.adobe.com/dc-acrobat-sdk-docs/pdfstandards/pdfreference1.0.pdf https://opensource.adobe.com/dc-acrobat-sdk-docs/pdfstandard...

sennight 4y ago

Heads-up: apparently some kind of signup is required to download anything from this page. So if you heartily dislike ISOs not because of cost, but because of how insane it is to make standards difficult to actually access at all - nothing has changed.

deleted 4y ago
[deleted]

btown 4y ago

It's worth noting that while https://www.pdfa.org/resource/iso-32000-pdf/ https://www.pdfa.org/resource/iso-32000-pdf/ mentions the 2011 patent release for PDF 1.7 (https://www.adobe.com/pdf/pdfs/ISO32000-1PublicPatentLicense.pdf https://www.adobe.com/pdf/pdfs/ISO32000-1PublicPatentLicense...) it makes no such mention of such a release for PDF 2.0. Additionally, https://www.pdfa-inc.org/eula/ https://www.pdfa-inc.org/eula/ seems to indicate that you may only use the downloaded files on one computer - and does not establish a license agreement between the user and any third party IP holders. No-cost access does not mean free-as-in-software. Caveat emptor.

LegionMammal978 4y ago
Formally speaking, I'm pretty sure you can satisfy the terms of the EULA by "buying" another copy of the files (another instance of the "Product") for every computer you want to store it on. IANAL though. (And regardless, it definitely doesn't meet the principles of freedom as in free software.)

dawidpotocki 4y ago

> ISO 32000-2 was also, however, the first and only core PDF specification published exclusively — and only for purchase — by ISO, inhibiting its use and adoption over the last five years. Who would have thought that "international standards" that require payment don't work well? How many people are willing to spend a couple hundred CHFs to access the PDF specs? Also it seems insane to me that the PDF creator, Adobe, now has to pay ANSI to distribute their own spec for free. For some reason you still need to "add to cart" the standards and they will ask you for your address and email. You don't need to provide real information for anything, not even email, they just redirect you to a page with download links. Also the EULA is insane. > You may install one copy of the Product on, and permit access to it by, a single computer owned, leased or otherwise controlled by you. In the event that computer becomes dysfunctional, such that you are unable to access the Product, you may transfer the Product to another computer, provided that the Product is removed from the computer from which it is transferred and the use of the Product on the replacement computer otherwise complies with the terms of this Agreement. Neither concurrent use on two or more computers nor use in a local area network or other network is permitted. You may print one copy of the Product for your personal use. You shall not merge, adapt, translate, modify, rent, lease, sell, sublicense, assign or otherwise transfer any of the Product, or remove any proprietary notice or label appearing on any of the Product. You may make one (1) copy the Product for backup purposes only. They don't even allow you to use it on your 2 devices at the same time. Complete nonsense that I'm sure everyone will follow.

vasco 4y ago
When nobody tells lawyers no, this is what happens. This protects nobody other than some lawyers feeling fuzzy that they "mitigated risks" for their customer.
- anticensor 4y ago
  What if they are not allowed to say no to lawyers?
  - sennight 4y ago

LegionMammal978 4y ago

One interesting thing I noticed is that the shortest conforming PDF 2.0 file clocks in at 254 bytes long (if you strip out the indentation): %PDF-2.0 1 0 obj<</Count 0/Kids[]/Type/Pages>>endobj 2 0 obj<</Pages 1 0 R/Type/Catalog>>endobj xref 0 3 0000000000 65535 f 0000000009 00000 n 0000000053 00000 n trailer<</ID[( )( )]/Root 2 0 R/Size 3>> startxref 96 %%EOF This is 41 bytes longer than the shortest conforming file in PDF 1.0 through PDF 1.7, which do not require the ID entry in the file trailer dictionary. (Apart from the ID entry and file header, the shortest file is otherwise identical.) The standard justifies its mandatory inclusion by saying that "some workflows" require PDF files to be "uniquely identified". I wonder what sort of workflows those might be.

popcorncowboy 4y ago
DRM fingerprinting
- LegionMammal978 4y ago
  At least the standard doesn't seem to support that: it suggests creating the ID by hashing the current time, file path, and file size. Besides, there are a billion other side channels that can be used to digitally watermark PDFs. Anyway, I've since found an explanation in the PDF 1.7 spec. PDF files can include "file specifications" (file paths or URLs) to refer to other files. An ID can be added to a file specification for an external PDF, which the PDF reader can validate against the ID contained in the located file's trailer dictionary, to ensure that the external PDF is the expected one. I guess "some workflows" must have gotten upset when trying to generate a link to a PDF file with no ID, so they finally required its presence in the spec.

ShadowBanThis01 4y ago

Nothing encumbered by fees or patents should be accepted as a "standard." Period.

legulere 4y ago
The problem is that work on standards costs a lot of money. Somehow we need to pay for that. The solution could be the state.
- kajaktum 4y ago
  Like what? And if they do, is it really sustainable? Are these standard organisations really funded by the papers they sell?
  - justeleblanc 4y ago
    ISO is funded by sales and membership fees from member states. It's been around for 75 years. If they're not sustainable, I don't know what organizations are.
- ajsnigrutin 4y ago
  But what is a standard? Either one company or multiple companies wanting to be interoperable with their software decide on a way to save data (communicate, whatever), so more people buy their software and use their prouducts. Adobe has an interest for more and more people to use PDFs because more people will then buy their products.. if they're afraid of the costs, don't publish the standard and risk people switching to other stanards.
- johannes1234321 4y ago
  The fun is: The fees for obtaining the standard doesn't really go to the ones who create the standard. Standard is created by volunteers typically sponsored by their employer to go to standards meetings, who also pay (depending on national body) for being members.
  - 4y ago

GoblinSlayer 4y ago

Or just write plaintext documents IETF style.

chrismorgan 4y ago
IETF RFCs haven’t been plain text for quite some years. RFC 2629 (June 1999) defined the first XML vocabulary, and RFC 7990 (December 2016) completed the process of declaring an XML format the canonical source, rather than plain text. To learn more, start at https://www.rfc-editor.org/rse/format-faq/ https://www.rfc-editor.org/rse/format-faq/.
- Karunamon 4y ago
  That's just for ease of translation into other formats, right? No human is reading/implementing the XML.
  - chrismorgan 4y ago
    I don’t know altogether. I know it’s common to author in something else and then convert into the canonical XML form, but I’d be surprised if it wasn’t also common to author in the XML format. It’s not an onerous format.

Sephr 4y ago

No cost... except a ton of your personal info.

cbg0 4y ago
You can lie on the Internet.

Titan2189 4y ago

Unsure how long it'll be valid, but to save you having to enter fake details, here you go: https://www.pdfa-inc.org/?download_file=2009&order=wc_order_UEpidrGCqkJ2Z&uid=0c7e6a405862e402eb76a70f8a26fc732d07c32931e9fae9ab1582911d2e8a3b&key=731a8741-5998-4a59-a37b-e24b0316f765 https://www.pdfa-inc.org/?download_file=2009&order=wc_order_...

_a9 4y ago
Thanks, popped into archive.org too https://web.archive.org/web/20230406111824/https://www.pdfa-inc.org/?download_file=2009&order=wc_order_UEpidrGCqkJ2Z&uid=0c7e6a405862e402eb76a70f8a26fc732d07c32931e9fae9ab1582911d2e8a3b&key=731a8741-5998-4a59-a37b-e24b0316f765 https://web.archive.org/web/20230406111824/https://www.pdfa-...

chrisshroba 4y ago

The discussion around this being a non-free standard encumbered with license restrictions makes me wonder: is there an alternative for pixel-perfect rich document rendering? HTML needs sandboxing to be safe, rtf is barebones, and .docx has external dependencies.

herodotus 4y ago
I worked on PDF for years, and yearned for a better way to render pixel perfect. I think that handling of lines, shapes and images could be drastically simpler, but, alas, handling Glyphs (characters/fonts) will always be a nightmare of complexity.
wongarsu 4y ago
The obvious example would be PostScript. After all, PDF grew out of a desire to have a postscript variant better suited for digital documents instead of just printing. Illustrator's file format (.ai) was also just postscript up to version 8 or so.
nayuki 4y ago
If you're describing an image format where all subobjects are bitmaps and not vectors, and all math is done with integers, then pixel perfection is possible. Once you introduce any mildly interesting vector or typesetting feature, you will not get pixel perfection. Examples: * You want to draw a circle. Antialiasing is desirable because jaggies look really ugly. Do you want to prescribe the exact antialiasing algorithm? What about other ones that are faster or more accurate? Which AA convolution kernel are you using - box, Gaussian, sinc? * Which approximation algorithm will you use to draw cubic Bézier curves? I don't think there is a closed-form solution for them. * You support affine transformations. Define a 10×10 square. Scale it by 1/100. Scale it by 100. What if, due to floating-point rounding errors, your square is now 9.999×9.999 and now renders to 9×9 pixels without antialiasing? * You support automatic text wrapping. One renderer uses float32, looks at how wide each word is, and decides to break at some point in the sentence. Another renderer uses float64, looks at how wide each word is, and decides to break at a different point in the sentence.
layer8 4y ago

xtiansimon 4y ago

Half-joking—-Does the standard explain why some documents I open in Acrobat Reader ask me if I want to save, when I only opened the file (and made no intentional edits)??

planede 4y ago
PDF includes javascript as an extension, although I don't know if javascript actions can be triggered without user input or not. Also many PDF viewers have little to no support to javascript in PDF.
layer8 4y ago
This can happen for PDFs that are broken in some way and that Acrobat auto-repairs, and thus regards as modified. And no, the standard doesn’t concern itself with that particular behavior. Also, many PDFs “in the wild” do not fully conform to the standard, because Acrobat Reader is so lenient.

makkesk8 4y ago

The way pdf has become a standard in everyday life is truly disgusting. One is expected nowadays to have a pdf reader installed on your device, this is a problem in it self because most of the software short of just reading the pdf, that are "free" does not include most of the features one would come to expect to utilize the standard. Now I don't have to sign pdf's daily but when you start a new job for instance and have to sign a pdf it becomes troublesome. As a developer the ecosystem is pretty terrible too, in order to utilize said functions such as signing you'd need to fork out a huge chunk for a subscription to some library. Don't get me wrong, paying for software I'm all for but forcing your users to pay for some third-party software to interact with your documents is not fine. To me, this is simply disgusting that you'd have to buy into this "standard" in every aspect, both as a user and as a developer. We've come a long way over the years of having more options to both users and developers but honestly, it's simply not enough. And pdf as a format being very complex it's more than understandable that it would be a challenge to make it more available.

mindyhausler 4y ago

[dead]