> On 30 Mar 2016, at 08:57, Olaf Drümmer <[email protected]> wrote: > > Hi John, > >> On 30.03.2016, at 03:16, John Hewson <[email protected]> wrote: >> >> PDF/A is for archiving, and while PDF/A-2 does support JPEG 2000, it's not a >> good choice for an archival format, because most JPEG 2000 implementations >> are broken in some way and many PDF viewers cannot correctly view such >> files. It was essentially a failure as a file format and will be deprecated >> in PDF 2.0. If the goal of archiving with PDF/A is to produce reliable >> files, JPEG 2000 conflicts with that goal. > > as a matter of fact JPEG2000 is neither deprecated in PDF 2.0 nor has it been > considered for deprecation in the PDF 2.0 working group (WG 8 at ISO TC 171 > SC 2).
Thank you for pointing this out. Am I thinking of another image format, or are none of them being considered for deprecation at this time? > In terms of perceived usefulness (and suitability for archival purposes) of > of JPEG2000, I have to say that my impression is that JPEG2000 has strong > followers at least in some archival communities. While implementing a good > JPEG2000 compressor can be quite an engineering challenge and CPU intensive, > decompressing JPEG2000 is not overly complex (and archivists' main concern > should be decompression). JPEG2000 certainly has its fans, but I'm not one of them. Our experience has been that we have not found a fully working open-source JPEG2000 decoder. It remains an open issue for PDFBox. Couple that with the difficulty of encoding the format means there's a non-zero chance that you're creating bad archive files, and combine it with the fact that the reference implementation itself is broken, the spec is nearly impossible to understand, and the patent situation is unclear and you're looking at a pretty risky file format unless you're prepared to pay for propitiatory encoders/decoders. -- John > Olaf > > > --------------------------------------------------------------------- > To unsubscribe, e-mail: [email protected] > For additional commands, e-mail: [email protected] > --------------------------------------------------------------------- To unsubscribe, e-mail: [email protected] For additional commands, e-mail: [email protected]
