Fixing the PostScript generated from PDF files by Acrobat Reader 3.0

Dan Ellis 1997sep05

Sometimes you want the PostScript of a file that you have converted to PDF. A common case is when you are trying to distribute a postscript file that you have been able to convert successfully into PDF (via Distiller) but which is fouling up some remote colleague's printer. Usually, the PS generated from PDF will be clean and in all likelihood smaller than the original.

Generating ps by using acrobat to print-to-file works well EXCEPT for a bug that ghostview finds. About 10946 chrs into the file is a block like:

Level2? StartLoad {
/gs
{
begin
/SA here { setstrokeadjust } if
/OP here { setoverprint } if
/BG here { setblackgeneration } if
/UCR here { setundercolorremoval } if
/HT here { sethalftone } if
/sethalftonephase isdefined? { /HTP here { sethalftonephase } if } if
/TR here
{
dup xcheck { settransfer } { aload pop setcolortransfer } ifelse
} if
end
} bd
{ /Default /Halftone findresource pop } stopped
{
currenthalftone exch defineresource pop }
if
} EndLoad
Level2? not StartLoad {
/gs
{
begin
/SA here { /_sa? xdd } if
/OP here { dup /_op? xdd
/setoverprint where {pop setoverprint}
{pop} ifelse
} if
/HT here { sethalftone } if
/TR here { dup xcheck
{ settransfer }
{ pop }
ifelse } if
end
} bd
5 dict dup
begin
currentscreen 1 [/HalftoneType /SpotFunction /Angle /Frequency]
{ exch def } forall
end
/Default exch /Halftone defineRes pop
} EndLoad

The first block is a disaster, so force it to use the level1 version: replace the two calls to Level2? with false.