-----Original Message----- From: cctalk [mailto:cctalk-bounces at classiccmp.org] On Behalf Of Chuck Guzis Sent: Saturday, February 18, 2017 4:04 PM To: General Discussion: On-Topic and Off-Topic Posts Subject: Re: PDF PDF Which is right and which is ... Was Re: PDP-11/24 CPU later version On 02/18/2017 11:24 AM, COURYHOUSE at aol.com wrote: with OCR future? When scanning documents and converting to PDF, I've found that ghostscript works fine (under Linux). There's also a separate tiff to pdf converter available as a package. Some people use ImageMagick There are also a number of free online conversion websites; I've used a couple and they seem to be pretty decent. --Chuck ----- http://www.differencebetween.net/technology/software-technology/difference-b etween-pdf-and-pdf-a/ is a concise description Summary: - PDF/A is a special type of PDF meant for archiving documents - PDF/A does not allow audio, video, and executable content while PDF does - PDF/A requires that graphics and fonts be embedded into the file while PDF does not - PDF/A does not allow external references while PDF does - PDF/A does not allow encryption while PDF does Those are all good archival properties! However, it's also R/O. For my purposes PDF/A is undesirable because I can't: (1) OCR it. (2) Extract pages. (3) Combine sectioned files into a single document. (4) Rotate pages permanently. It's the R/O part that is "mighty unhelpful" since it precludes basic document management. Gotta hope that the archivist made good choices. But the choices of an archivist aren't necessarily those of a user with a day-to-day need to fix stuff :-<. I can see value for a processing stream that uses a PDF/A intermediary to ensure the desirable properties listed above (e.g., font embedding) but then a final save in standard "open" PDF that allow users to accomplish the types of manipulations that I've listed. ----- paul

On 2017-02-19 4:39 AM, Nico de Jong wrote: Y'all realise we're dealing with bundles of *scanned images* in the context of this discussion. Often the source material is a multipage TIFF from the scanner or other processing step. So relevant tools are things like tiff2pdf (tiffutils), and tumble as cited on http://bitsavers.trailing-edge.com/ My objection to PDF/A doesn't really stand if there are good open source tools to process it (clearly the Adobe tools don't count). --T

-----Original Message----- From: cctalk [mailto:cctalk-bounces at classiccmp.org] On Behalf Of Mouse Sent: Sunday, February 19, 2017 10:07 AM To: cctalk at classiccmp.org Subject: Re: PDF PDF Which is right and which is ... Was Re: PDP-11/24 CPU later version Maybe if you stick to Adobe's tools. As demonstrated by this thread, it's entirely possible to modify such files, even if the currently-easy ways to do that involve a trip through a completely different representation. I find it astonishing that anyone would seriously call any documented file format read-only. (If PDF/A isn't documented, then IMO it's not suitable for archival under any circumstances. But this thread makes it sound as though it's documented.) /~\ The ASCII Mouse \ / Ribbon Campaign X Against HTML mouse at rodents-montreal.org / \ Email! 7D C8 61 52 5D E7 2D 39 4E F1 31 3E E8 B3 27 4B ----- I wasn't intending to make an existential claim. I was making an observation that, yes, was based on experience with a particular tool. And now I've found how to extend that tool to remove that limitation, thank you Guy :->. PDF/A still has properties that are specific to a community-of-use. Evidently Al thinks those properties are detrimental to the intent of Bitsavers? I wasn't previously aware of that issue; perhaps others here were also unaware? ----- paul