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Re: pdf editor ?



On 19-Mar-01 Hall Stevenson wrote:
> Ultimately, if you want to edit anything, you need the original. I
> don't think you can even create a PDF "from scratch" or from nothing.
> You have to start with another file.

Well, in fact you can, if you understand the PDF format (which is
far from easy), since a valid PDF file can be written as ASCII text
-- even one which includes graphics and fancy fonts.

A PDF document in ASCII looks a bit like XML, only with different
words. An example is attached (base64-encoded to avois line breaks).

Admittedly I created it by converting the PostScript source for an
example in the Blue Book, for which the source is:

  %!PS-Adobe-3.0
  /inch {72 mul} def
  /wedge { newpath
  %%  rgbR rgbG rgbB setrgbcolor
    0 0 moveto  1 0 translate  15 rotate  0 15 sin translate
    0 0 15 sin -90 90 arc  closepath} def
  gsave
  %%0 inch 0 inch translate  3 inch 4 inch translate
    0.5 inch 0.5 inch scale  0.02 setlinewidth
    1 1 12  { 12 div setgray
      gsave  wedge gsave fill grestore  0 setgray stroke  grestore
      30 rotate  } for
  grestore
  showpage

but, as you can see from the PDF file, I could in principle
have simply typed it once I had worked out what to type.

Ted.


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E-Mail: (Ted Harding) <Ted.Harding@nessie.mcc.ac.uk>
Fax-to-email: +44 (0)870 284 7749
Date: 20-Mar-01                                       Time: 00:04:11
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Attachment: rose.pdf
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