8 ms·

Tell HN: Adobe took down the PDF 1.7 specification from their site

114 points by steerablesafe 4y ago

I just discovered that Adobe took down the PDF 1.7 specification from their site. It's used to be hosted at [1] and I can't find a replacement. Of course this doesn't mean that the specification can't be acquired freely from elsewhere [2, 3], but it's unfortunate if the authoritative source is down. Hopefully it is a mistake though and it will be back up. [1] http://www.adobe.com/content/dam/acom/en/devnet/pdf/pdfs/PDF32000_2008.pdf [2] https://christianhaider.de/dokuwiki/lib/exe/fetch.php?media=pdf:pdf32000_2008.pdf [3] https://web.archive.org/web/20220309040754if_/https://www.adobe.com/content/dam/acom/en/devnet/pdf/pdfs/PDF32000_2008.pdf

hulitu 4y ago
Maybe they want to sell it :)
colejohnson66 4y ago
It's possible they're reworking their CMS and that causes files to be moved (breaking links everywhere). Microsoft loves doing that with their developer blogs.
- hunter2_ 4y ago
  Not cool [0]. It's funny how CMSes tend to offer "clean URL" configurations (meaning that everything after the origin is 100% controlled by the CMS user) for requests served dynamically (database queries) but requests served statically (public files on disk) often end up containing implementation-specific junk (e.g., "/sites/" in the case of Drupal). The magic that makes clean dynamic URLs (rewrite everything that isn't a file to the boot script) should be expanded to make clean file URLs. Serving files would then need help from a script+db, but so what, that already happens for private files. Obviously embedded assets that need to be fast (images, stylesheets, scripts, etc.) can't have a slow db query in the way. I'm only talking about files that are a first-class destination in the browser's address bar, like PDFs, and anything where the disposition is that it lands in your Downloads folder. Stuff that might be a search result or otherwise linked-to. [0] https://www.w3.org/Provider/Style/URI https://www.w3.org/Provider/Style/URI
  - innocenat 4y ago
    Drupal allow you to set private file mode, which has clean URL.
    - hunter2_ 4y ago
      It's kind of clean in that it uses a URL based on a db value instead of the filename on disk, but it's still got CMS-specific junk in that it always starts with "/system/" (at least in D7, I haven't explored it in D9).
dorianmariefr 4y ago
> This page was updated on 23 March 2022 as many direct links to legacy PDF specifications on adobe.com were broken. Many links now reference the Wayback Machine internet archive and thus may be slow. https://www.pdfa.org/resource/pdf-specification-index/ https://www.pdfa.org/resource/pdf-specification-index/
jeffreportmill1 4y ago
Off topic, but man is that document hard to use as a reference. Ironically, I wish they would publish it as HTML broken down by chapter and section. (I have used that document a lot to write a custom PDF generator and parser in Java, using a downloaded copy)
- fivea 4y ago
  > Ironically, I wish they would publish it as HTML broken down by chapter and section. I wish there was an EPUB version of the document. Do PDFs support reflowable content?
  - HWR_14 4y ago
    I believe one of the selling points of PDFs was the absolute lack of reflowing content.
    - hunter2_ 4y ago
      Right, as the point is to represent a physical document, paper and ink (or canvas, toner, whatever -- stuff that doesn't reflow). Why anyone would use such a format for these situations, where the audience definitely cares way more about consuming it on an electronic device than printing it out, is... mind-boggling. Of course, AI+ML to the rescue: Liquid Mode [0]. > Files are processed in our secure data servers and immediately deleted from our servers after the experience is generated. [0] https://www.adobe.com/devnet-docs/acrobat/android/en/lmode.html https://www.adobe.com/devnet-docs/acrobat/android/en/lmode.h...
      - HWR_14 4y ago
        I've found people being precise about the flow of equations and text intermixed can be easier to read than reflowing content. Other than that, not so much. Edit: Non-reflowing content also works well if you need to refer people to page numbers and paragraphs. I look forward to playing with liquidmode at some point soon.
darrenf 4y ago
It's still available at this Adobe URL: https://opensource.adobe.com/dc-acrobat-sdk-docs/standards/pdfstandards/pdf/PDF32000_2008.pdf https://opensource.adobe.com/dc-acrobat-sdk-docs/standards/p... "As distributed by Adobe after adoption as ISO 32000-1:2008, with permission of ISO." [0] Not to mention ISO unsurprisingly host it, which I would also consider authoritative: https://www.iso.org/obp/ui/#iso:std:iso:32000:-1:ed-1:v1:en https://www.iso.org/obp/ui/#iso:std:iso:32000:-1:ed-1:v1:en [0] https://www.loc.gov/preservation/digital/formats/fdd/fdd000277.shtml https://www.loc.gov/preservation/digital/formats/fdd/fdd0002...
- pointlessone 4y ago
  How did you find the link on opensource.adobe.com? The used to host other standards, too (e.g. font formats).
- Anunayj 4y ago
  kinda funny you need a pdf reader to read the pdf specification :)
  - mdaniel 4y ago
    I somehow thought early versions of the PDF spec were published as a .ps version for that very reason, but my duck-fu is failing me finding any such link. It may require wayback-fu and that's beyond my level-of-effort :-)
  - geodel 4y ago
    Its same with html spec I think.
    - zdw 4y ago
      HTML is somewhat human readable in a text editor, but PDF likely is not.
      - yardshop 4y ago
        Actually a lot of the PDF format is plain text, but can contain binary streams. You can open a PDF in a text editor and see the header, and skip to the end and see the xref index and some other parts. The binary sections are enclosed in plain text start and end markers, but you probably won't be able to read much of the actual content this way since it will be compressed or encrypted.
iceblockderby 4y ago
The ISO released the 2.0 version of the specification that replaces the 1.7 standard. "Although it is an open standard, one major difference compared with prior versions of PDF is that ISO now holds the copyright to the PDF specification and thus PDF 2.0 is not freely downloadable." [0] It looks like DMCA requests are being issued to anyone that hosted the old specification, even open source projects [1]. [0] https://www.pdfa.org/resource/iso-32000-pdf/ https://www.pdfa.org/resource/iso-32000-pdf/ [1] https://github.com/Hopding/pdf-lib#git-history-rewrite https://github.com/Hopding/pdf-lib#git-history-rewrite
- mr337 4y ago
  Wow, I feel like that is a step back. This feels a lot like other protocols non free specs like J1939 that is over $1000USD.
  - prima-facie 4y ago
    PDF 2.0 is not cheap either: https://www.iso.org/standard/75839.html https://www.iso.org/standard/75839.html Definitely a step back.
    - hoofedear 4y ago
      Why are these documents a paid product? Are there other ways to access it? I figured standardization documentation would be free to encourage adoption.
andrewmcwatters 4y ago
Maybe one of the side effects of this is that people only continue writing against PDF 1.7.

114 points by steerablesafe 4y ago

hulitu 4y ago

Maybe they want to sell it :)

colejohnson66 4y ago

It's possible they're reworking their CMS and that causes files to be moved (breaking links everywhere). Microsoft loves doing that with their developer blogs.

hunter2_ 4y ago
Not cool [0]. It's funny how CMSes tend to offer "clean URL" configurations (meaning that everything after the origin is 100% controlled by the CMS user) for requests served dynamically (database queries) but requests served statically (public files on disk) often end up containing implementation-specific junk (e.g., "/sites/" in the case of Drupal). The magic that makes clean dynamic URLs (rewrite everything that isn't a file to the boot script) should be expanded to make clean file URLs. Serving files would then need help from a script+db, but so what, that already happens for private files. Obviously embedded assets that need to be fast (images, stylesheets, scripts, etc.) can't have a slow db query in the way. I'm only talking about files that are a first-class destination in the browser's address bar, like PDFs, and anything where the disposition is that it lands in your Downloads folder. Stuff that might be a search result or otherwise linked-to. [0] https://www.w3.org/Provider/Style/URI https://www.w3.org/Provider/Style/URI
- innocenat 4y ago
  Drupal allow you to set private file mode, which has clean URL.
  - hunter2_ 4y ago
    It's kind of clean in that it uses a URL based on a db value instead of the filename on disk, but it's still got CMS-specific junk in that it always starts with "/system/" (at least in D7, I haven't explored it in D9).

dorianmariefr 4y ago

> This page was updated on 23 March 2022 as many direct links to legacy PDF specifications on adobe.com were broken. Many links now reference the Wayback Machine internet archive and thus may be slow. https://www.pdfa.org/resource/pdf-specification-index/ https://www.pdfa.org/resource/pdf-specification-index/

jeffreportmill1 4y ago

Off topic, but man is that document hard to use as a reference. Ironically, I wish they would publish it as HTML broken down by chapter and section. (I have used that document a lot to write a custom PDF generator and parser in Java, using a downloaded copy)

fivea 4y ago
> Ironically, I wish they would publish it as HTML broken down by chapter and section. I wish there was an EPUB version of the document. Do PDFs support reflowable content?
- HWR_14 4y ago
  I believe one of the selling points of PDFs was the absolute lack of reflowing content.
  - hunter2_ 4y ago
    Right, as the point is to represent a physical document, paper and ink (or canvas, toner, whatever -- stuff that doesn't reflow). Why anyone would use such a format for these situations, where the audience definitely cares way more about consuming it on an electronic device than printing it out, is... mind-boggling. Of course, AI+ML to the rescue: Liquid Mode [0]. > Files are processed in our secure data servers and immediately deleted from our servers after the experience is generated. [0] https://www.adobe.com/devnet-docs/acrobat/android/en/lmode.html https://www.adobe.com/devnet-docs/acrobat/android/en/lmode.h...
    - HWR_14 4y ago
      I've found people being precise about the flow of equations and text intermixed can be easier to read than reflowing content. Other than that, not so much. Edit: Non-reflowing content also works well if you need to refer people to page numbers and paragraphs. I look forward to playing with liquidmode at some point soon.

darrenf 4y ago

It's still available at this Adobe URL: https://opensource.adobe.com/dc-acrobat-sdk-docs/standards/pdfstandards/pdf/PDF32000_2008.pdf https://opensource.adobe.com/dc-acrobat-sdk-docs/standards/p... "As distributed by Adobe after adoption as ISO 32000-1:2008, with permission of ISO." [0] Not to mention ISO unsurprisingly host it, which I would also consider authoritative: https://www.iso.org/obp/ui/#iso:std:iso:32000:-1:ed-1:v1:en https://www.iso.org/obp/ui/#iso:std:iso:32000:-1:ed-1:v1:en [0] https://www.loc.gov/preservation/digital/formats/fdd/fdd000277.shtml https://www.loc.gov/preservation/digital/formats/fdd/fdd0002...

pointlessone 4y ago
How did you find the link on opensource.adobe.com? The used to host other standards, too (e.g. font formats).
Anunayj 4y ago
kinda funny you need a pdf reader to read the pdf specification :)
- mdaniel 4y ago
  I somehow thought early versions of the PDF spec were published as a .ps version for that very reason, but my duck-fu is failing me finding any such link. It may require wayback-fu and that's beyond my level-of-effort :-)
- geodel 4y ago
  Its same with html spec I think.
  - zdw 4y ago
    HTML is somewhat human readable in a text editor, but PDF likely is not.
    - yardshop 4y ago
      Actually a lot of the PDF format is plain text, but can contain binary streams. You can open a PDF in a text editor and see the header, and skip to the end and see the xref index and some other parts. The binary sections are enclosed in plain text start and end markers, but you probably won't be able to read much of the actual content this way since it will be compressed or encrypted.

iceblockderby 4y ago

The ISO released the 2.0 version of the specification that replaces the 1.7 standard. "Although it is an open standard, one major difference compared with prior versions of PDF is that ISO now holds the copyright to the PDF specification and thus PDF 2.0 is not freely downloadable." [0] It looks like DMCA requests are being issued to anyone that hosted the old specification, even open source projects [1]. [0] https://www.pdfa.org/resource/iso-32000-pdf/ https://www.pdfa.org/resource/iso-32000-pdf/ [1] https://github.com/Hopding/pdf-lib#git-history-rewrite https://github.com/Hopding/pdf-lib#git-history-rewrite

mr337 4y ago
Wow, I feel like that is a step back. This feels a lot like other protocols non free specs like J1939 that is over $1000USD.
- prima-facie 4y ago
  PDF 2.0 is not cheap either: https://www.iso.org/standard/75839.html https://www.iso.org/standard/75839.html Definitely a step back.
  - hoofedear 4y ago
    Why are these documents a paid product? Are there other ways to access it? I figured standardization documentation would be free to encourage adoption.

andrewmcwatters 4y ago

Maybe one of the side effects of this is that people only continue writing against PDF 1.7.