[Scribus] EPS in PDF?

[Craig Ringer]

Terry Brown wrote:
> Hi All,
> 
> I thought it was possible to embed EPS directly in PDF... but 
> perhaps I'm wrong?

If it is, I'd be DELIGHTED if you could point out any resources that 
document how (with reference to the PDF standard - no "it works in most 
viewers" allowed here). I doubt it though - that'd involve injecting a 
PostScript language stream into a PDF, requiring the PDF viewer to embed 
a full PostScript interpreter (like GhostScript) to support rendering 
it. Given the problems with this and resulting lack of support for it in 
PDF, Scribus rasterises the EPS using GhostScript and embeds that raster 
image.

If you're used to EPS files being embedded "as is" in PDF, I think it 
more likely that you're used to applications that generate PDF through a 
`distilling' process. These apps output PostScript - including any EPS 
files inline in the PostScript - and then rely on an external tool to 
convert the combined document to PDF. It's a powerful approach, but 
slower, clumsier, and more error prone. In my view directly generating 
the PDF should be (when optimally implemented) much more reliable and a 
lot faster, as well as a lot easier to get the exact results you want with.

The main advantage of a `distilling' style of PDF output is that you can 
embed EPS files - since they're just a PostScript snippet _designed_ to 
be embedded in a larger PostScript (but not PDF) stream.

It is worth noting that Scribus is quite capable of using this workflow 
in combination with an external tool like Adobe Acrobat Distiller or 
GhostScript. For gs use version 8.5x or newer and **IMPORTANT** use 
-dPDFSETTINGS=/prepress . The primary downside is that PostScript output 
in Scribus is to an extent the poor cousin - it gets less attention and 
less priority than PDF, because PDF is seen as the primary output format 
and the one the app must maintain maximum quality for. That said, the 
only long standing issue I'm aware of with PostScript output is the lack 
of a built-in transparency flattener (this also affects PDF 1.3 output), 
causing transparent objects to be output incorrectly. If you avoid 
transparency you'll be just fine outputting to PostScript - with any EPS 
files - and converting to PDF after generating your PS file.

With luck that last issue with the flattener can be fixed as part of the 
migration to the Cairo rendering library. I'm not 100% sure though - 
I've been rather out of touch lately due to uni and work pressures.

> Or just some EPSs?  Scribus seems to want to 
> convert the EPS to a bitmap first, which works, but with a high 
> resolution and colourful EPS it takes a long time to produce and 
> makes a big PDF file.

That's right. I've described the only workaround I'm aware of above, and 
the reasons why.

> I tried importing the original SVG (from Inkscape) and also the EPS 
> (from Inkscape) but the SVG seemed to crash Scribus (or I didn't 
> wait long enough, but I waited several minutes) and the EPS came in 
> minus the correct colours.

The EPS importing with the wrong colours is interesting. Please make 
VERY certain you're using the lastest GhostScript. If you're using gs7, 
that's your problem; even 8.15 has known issues. If you have confirmned 
you're using the lastest gs, please attach a sample EPS to a new report 
in http://bugs.scribus.net/ and include a detailed description of the 
problem including expected and actual results and preferably a screenshot.

AFAIK the SVG importer is not able to handle the full SVG standard (feel 
free to correct me if this is out of date) and won't handle everything 
with 100% fidelity. In particular I think there are problems with 
gradients - SVG supports gradients with origins "outside" the object; 
Scribus does not (because PDF 1.3 and PostScript 3 do not, and that's 
the imaging model Scribus uses). I think that can be fixed by outputting 
the gradient as a separate object with a mask but don't know if/when 
this can/will be supported.

> So I'm wondering what the recommended route for getting vector 
> images into PDFs through Scribus is - perhaps things drawn in 
> Scribus are the most reliable?

The latter point is certainly true. I'm not sure what the best way is 
otherwise though... I thought it was EPS import, really, especially 
after the recent work that was done on it to improve its reliability and 
completeness.

--
Craig Ringer