[Openicc] [argyllcms] OT: PDF frustration

[Joshua L. Blocher]

Hal V. Engel wrote:
> Actually the problem is even worse with regard to poppler.  The new Common 
> Printing Dialog (CPD) that is being worked on by the printing community and 
> that will be a standard "feature" of many Linux distros in the not too distant 
> future will only accept PDF files for preview and printing and it does all of 
> it's processing using poppler.  In addition at some point all linux/unix 
> printing work flows will be  PDF based rather than using PostScript.  As part 
> of the conversion from PostScript to PDF a new PDF to raster CUPS filter is 
> being developed by the printing community (it is currently a 0.4.x version and 
> is mostly working other than CM) and it is also based on poppler. This means 
> that until CM in poppler is fixed or the CUPS PDF to raster filter is 
> rewritten to use a pdf to raster library with CM support that there will be no 
> color managed printing work flows in Linux/Unix systems other than those that 
> handle it at the application level (like today).  The sad part about this is 
> that ghostscript already has some CM capabilities thanks to Graeme and the 
> ghostscript team is in the process of implementing complete support.  A PDF to 
> raster CUPS filter based on ghostscript instead of poppler would likely have 
> had full CM support long before most users systems had been converted to a PDF 
> based printing work flow and all of these systems would have had CM by default 
> at that point as part of the printing system.  
>
> The real question is what do we do about it?  I have also been in contact with 
> the printing community about this and there seems to be little interest in 
> converting to ghostscript for either the CPD or the new CUPS pdftoraster 
> filter.  In addition poppler is widely used in various viewers such as Evince 
> and Okular which means that the problem is more wide spread than just these 
> new printing work flows.  It could very well be a good idea to try to work 
> with the poppler team to implement CM in the poppler library since this would 
> correct this issue across a wider range of situations for users.  For some 
> reason I never received the last note in the thread about this on the poppler 
> email list.  So I was not too sure if they were receptive or not to getting 
> some help implementing CM.  But it appears that they are.  Having looked at 
> the poppler code in some detail a few months ago I have some idea of what 
> would be involved in implementing CM.  It would not be a small project in part 
> because the code is currently poorly structured to support this (IE. some 
> parts of the code would be need significant work to get it ready to add CM 
> support) but would be something that could be at least mostly done by a Google 
> Summer of Code type project (IE. one person full time for around 3 months).  
> In other words I think Lars' idea of a student project is a good one.   But I 
> am not sure how to go about organizing an effort like that.  
>
> One possibility is to have an OpenICC proposal for this as part of the 2009 
> Google Summer of Code but there are a number of issues with this.  First it 
> means that the soonest we would see this fixed in poppler would be around this 
> time next year.  Second we have no way of knowing if Google will select the 
> OpenICC again for next years program.   And finally we would not have any way 
> to assure that a student would be interested in this project and that this 
> project would be make the cut even if OpenICC were accepted by Google for 
> 2009. 
>
> Although Lars vented about this here I think this belongs on the OpenICC list 
> so I am cross posting my reply to the OpenICC list.  I think there are things 
> we can do to help the poppler project with this issue and I think that there 
> are others on OpenICC that might be able to suggest ways to approach this.   
> My last note to the poppler email list has some rough ideas about what needs 
> to be done and it could be used as a basis for a series of smaller projects 
> that could move poppler along in the desired direction.  This might make it 
> easier to find student volunteers for since these sub-projects would be 
> something that would be more approachable for a student. 
>
> One other thing.  Lars has a link in his note to a bug opened by Kai-Uwe about 
> three weeks ago but there is an existing CM bug open for poppler that was 
> opened 02/16/2008  https://bugs.freedesktop.org/show_bug.cgi?id=14526 .  I am 
> not sure why the Kai-Uwe bug is not closed as a duplicate of that bug. 
>
> Hal
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>   
Would using GSoC money earned this year be enough, to offer a bounty for 
this work.
I know bounties are not always the best way to get things done. But this 
seems like one
of the times it might help. A time sensitive project that needs someone 
with area expertise.

Just a idea.


Joshua L. Blocher
verbalshadow