EPS, PS, SubFileDecode, ReusableStreamDecode

[tgreer]

Ok folks! All of these posts regarding EPS in Forms, using filters and so on, have a MISTAKE. Thanks to an emailer for digging into this for me.

The problem appears in certain RIPs, when the SubFileDecode filter is used as a parameter for the ReusableStreamDecode filter. That's what this technique does. Notice the code snippet:

/ImageData
currentfile
<< /Filter /SubFileDecode
   /DecodeParms << /EODString (*EOD*) >>
>> /ReusableStreamDecode filter
% EPS code here
% etc, etc
*EOD* def

That's what I've been using and posting. However, the PostScript Language Reference Manual states on page 151:


"In LanguageLevel 2, EODCount and EODString are specified as operands on the stack. In LanguageLevel 3, they may alternatively be specified in theSubFileDecode parameter dictionary (as shown in Table 3.23). They must be specified in the parameter dictionary if the SubFileDecode filter is used as one of the filters in a ReusableStreamDecode filter (described in the next section)."


Notice, they must be specified. "They" meaning BOTH keys, including the /EODCount. So the code above should properly be:

/ImageData
currentfile
<< /Filter /SubFileDecode
   /DecodeParms << /EODCount 0 /EODString (*EOD*) >>
>> /ReusableStreamDecode filter
% EPS code here
% etc, etc
*EOD* def

I hope this helps!


Thomas D. Greer

http://www.tgreer.com

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Training, Development & Consulting