Bruno, To be honest, I don't know what differs between the two tools, as they both come from Cairo, I assumed that pdftops was just a small wrapper around the same code as pdftocairo but with the options pre-set for PS output.
I'm a Ghostscript developer, so I can't really answer specifics about Cairo - I know about the problems with the Cairo PDF output, as we've performance problems in Ghostscript with those, and have had some fairly lengthy (and heated) discussions with Cairo developers on the subject. And I have helped debug a lot of these problems with the Ghostscript output, so I can give general suggestions as I did above. If I had to guess, I would say that pdftocairo is possibly spotting that the PDF originated as a Cairo file, and is using "inside" knowledge of how those are constructed to convert it back into Cairo internal representation, which is then outputs to Postscript - with that level of extra information, it can probably be much, much smarter about when there is real transparency that it has to render, and when everything opaque, and remain in high level form. Whilst, pstops may be doing a simpler, one step PDF to Postscript conversion. Ideally, what you'd want to try is (if possible) to keep the "ProRes" (I thought it was "ImageRET") mode, but still tell pdftocairo to use 600 dpi, as you then may get the benefits of more the accurate dot placement, better halftone results, and possibly better color management, whilst keeping the quicker processing of the smaller image data. It's hard to know without deep inside knowledge, but (again) if I had to guess, I would suggest that the slightly lower quality halftone screen is what's causing the slight intensity shift you mention. HP are pretty tight lipped about these technologies, but I know other such systems tend to allow the halftoning to represent more shades of the color, without losing detail (generally there is a trade off: you can approximate lots of shades, but lose detail, or have great detail, but very few shades). Chris -- You received this bug notification because you are a member of Desktop Packages, which is subscribed to poppler in Ubuntu. https://bugs.launchpad.net/bugs/1476705 Title: postscript printer hideously slow in some cases (pdftops) Status in poppler package in Ubuntu: New Status in system-config-printer package in Ubuntu: New Bug description: With my (old) postscript printer, print a single page can take many minutes on some situations. It happens with some PDF files (not all) and Firefox printing of Google map, for example. When this happens, I observed in system monitor that pdftops is running continuously. After some manual PDF -> PS conversions, I see that pdftops inflates the file size for problematic cases, but is ok for other files (size similar to the original file, or even smaller). I don't know if modern Postscript printers can handle this quickly, but it's unacceptable here and certainly not an efficient way to print those files. So I suspect that pdftops should be fixed. For example, I join a problematic pdf produced by Google Map in Firefox. I tried many conversions. As you can see, I get a much larger file (36 times) with pdftops. It is worse with pdf2ps (and it takes longer to process), so replace pdftops by pdf2ps is not an option for me. However, pdftocairo quickly produces an efficient file. I have the same success if I open the PDF file with Evince and print it as a Postscript file. I get a similar file if I print to PS directly from Google Map (Firefox). Of course these small PS files produced by pdftocairo, Evince of Firefox print flawlessly on my printer. See also Bug # 1095498 which I suspect is the same (old) thing, but I fill a new one since it doesn't seem to be printer specific. Of course, another workaround could be to use a PCL driver but no one is available for my printer (HP Color Laserjet 2605dn). To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/poppler/+bug/1476705/+subscriptions -- Mailing list: https://launchpad.net/~desktop-packages Post to : desktop-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~desktop-packages More help : https://help.launchpad.net/ListHelp