pdfbox-users mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From John Hewson <j...@jahewson.com>
Subject Re: How can I write JPEG2000 encoded images in PDF?
Date Thu, 31 Mar 2016 11:22:34 GMT

> On 30 Mar 2016, at 08:57, Olaf Drümmer <olaflist@callassoftware.com> wrote:
> 
> Hi John,
> 
>> On 30.03.2016, at 03:16, John Hewson <john@jahewson.com> 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: users-unsubscribe@pdfbox.apache.org
> For additional commands, e-mail: users-help@pdfbox.apache.org
> 

---------------------------------------------------------------------
To unsubscribe, e-mail: users-unsubscribe@pdfbox.apache.org
For additional commands, e-mail: users-help@pdfbox.apache.org


Mime
View raw message