[gs-devel] Converting pdf to eps

[Yang]

Hello, this is a user-level question, but I could only find this devel 
list (which from the archives seems to also deal with user issues); if 
this is not the place to ask, please kindly point me in the right direction.

Some context: I (and many others I know) frequently need to convert 
between pdf and ps, but this process has always been a mystery to 
everyone I know (and since the results are frequently less than perfect, 
it is a process that is avoided when possible). Currently, I need to 
convert a pdf to an eps for use in a tex document, so I'd like to now 
understand once and for all what is going on.

I have been searching, reading, and experimenting all day with options 
to convert from pdf to ps without losing any quality (my main goal is to 
convert to eps, but I am having difficulty even getting to the ps step). 
I have tried:

ps2pdf: uses gs to produce postscript-3; results are terrible

convert: identical to ps2pdf

pstopdf: uses xpdf; seems to be the best so far, but is it perfect?

ps2ps2: uses gs to produce postscript-2; for some files, the result 
cannot be viewed in evince (errors); so far have always been able to 
view in gs or display; seems to yield high quality as well

The file sizes are dramatically different:

$ du -shx *
16K     convert.ps
16K     pdf2ps.ps
56K     pdftops.ps
112K    ps2ps2.ps
16K     source.pdf

I have many questions at this point, and would be grateful for answers 
to *any* of them:

What are the differences among these options?

Does pdftops perform lossless conversion? Does ps2ps2? They both seem to 
produce better quality, but I'm not sure the conversion is completely 
lossless, by which I mean I can fearlessly convert between pdf and ps 
for ad infinitum and not worry about degradation in quality.

I frequently use ps2pdf with prepress settings, which as far as I 
understand means lossless conversion. Hence, another way to frame my 
original question is whether there is an equivalent option for pdf2ps.

Why does pdf2ps yield abysmal results? My eye tells me it's rasterizing 
the fonts; is that true, and is that the only problem? Is there some way 
I can tell pdf2ps to produce high-quality output/can I use ghostscript 
to produce high-quality postscript-3? (I could find no documentation for 
pdf2ps on the website, and the man page is minimal.)

I have not had time to try the following, but another option is to use 
the GNOME or KDE printing facilities to print to a postscript file. Can 
anyone comment on the quality of this option?

Is postscript-2 inherently more verbose than postscript-3 (for 
equivalent constructs)?

Are there other (open-source) options? How do they compare?

Thanks a lot for clearing up these issues!

Yang