[vox-tech] another PS2PDF question [solved]

[Jonathan Stickel]

Dylan Beaudette wrote:
> On Monday 28 February 2005 12:46 pm, Jonathan Stickel wrote:
> 
>>Dylan Beaudette wrote:
>>
>>>Well, after a little bit of googling, it looks like there was a rather
>>>simple solution. Since ps2pdf14 and epstopdf were just sending some
>>>pre-defined parameters to ghost script, it is possible to setup the gs
>>>environment, and then call epstopdf:
>>>
>>>export GS_OPTIONS=-dPDFSETTINGS=/prepress
>>>epstopdf --nocompress file.eps
>>>
>>>This will produce a PDF of the correct page size, without JPEG
>>>compression on embedded images!
>>
>>I don't know if your images are color or not, but your solution is not
>>sufficient when dealing with embedded color images (at least for me).
>>I've found that I need to edit the "epstopdf" script.  The two lines
>>that deal with "GSOPTS" need to be changed to:
>>
>>my $GSOPTS = "-dAutoFilterColorImages=false
>>-dColorImageFilter=/FlateEncode ";
>>$GSOPTS = "-dEncodeColorImages=false " unless $::opt_compress;
>>
>>In fact, it is OK to compress the images as long as Flate encoding is
>>used rather that JPEG.  The above edit does this.
> 
> 
> Ah... Interesting. I wonder how or if the "-dPDFSETTINGS=/prepress" setting 
> and the ones that you suggested are related. Before trying your method my 
> images were looking good, with a final PDF size of 6.4Mb. After altering my 
> epstopdf script as you suggested, the PDF file is 54Mb, and the images *seem* 
> to be the same.... however it would take a bit of research to find out just 
> how different they are. Any suggestions on a good place to search for 
> answers?
> 
> 


Using my suggested hack, try "epstopdf foo.pdf", i.e. allow the default 
compression flag to stay on.  You should get a compressed (smaller) 
file, but the image should still be "crisp".

The best doc I can find is 
http://www.cs.wisc.edu/~ghost/doc/gnu/7.05/Ps2pdf.htm.  This, with trial 
and error, lead me to my suggestion above.  From what I can tell, the 
"prepress" setting has the same color image encoding options as the 
others, so I don't think the results will be much different.

Jonathan