Ubuntu Manpage: pstotext - extract ASCII text from a PostScript or PDF file

NAME

       pstotext - extract ASCII text from a PostScript or PDF file

SYNTAX

       pstotext [option|pathname]...

       where option includes:

       -cork
       -landscape
       -landscapeOther
       -portrait
       -
       -output file
       -gs command
       -debug
       -bboxes

DESCRIPTION

pstotext reads one or more PostScript or PDF files, and writes to standard output a
representation of the plain text that would be displayed if the PostScript file were
printed. As is described in the DETAILS section below, this representation is only an
approximation. Nevertheless, it is often useful for information retrieval (e.g., running
grep(1) or building a full-text index) or to recover the text from a PostScript file whose
source you have lost.

pstotext calls Ghostscript, and requires Aladdin Ghostscript version 3.51 or newer.
Ghostscript must be invokable on the current search path as gs. Alternatively, you can
use the -gs option to specify the command (pathname and options) to run Ghostscript. For
example, on Windows you might use -gs "c:\gs\gswin32c.exe -Ic:\gs;c:\gs\fonts".

pstotext reads and processes its command line from left to right, ignoring the case of
options. When it encounters a pathname, it opens the file and expects to find a
PostScript job or PDF document to process. The option - means to read and process a
PostScript job from standard input. If no - or pathname arguments are encountered,
pstotext reads a PostScript job from standard input. (PDF documents require random access,
hence cannot be read from standard input.) You can use the -output option to specify an
output file (remember to invoke it before the input file); otherwise pstotext writes to
standard output.

The option -cork is only relevant for PostScript files produced by dvips from TeX or LaTeX
documents; it tells pstotext to use the Cork encoding (known as T1 in LaTeX) rather than
the old TeX text encoding (known as OT1 in LaTeX). Unfortunately files produced by dvips
don't distinguish which font encodings were used.

The options -landscape and -landscapeOther should be used for documents that must be
rotated 90 degrees clockwise or counterclockwise, respectively, in order to be readable.

The options -debug and -bboxes are mostly of use for the maintainers of pstotext. -debug
shows Ghostscript output and error messages. -bboxes outputs one word per line with
bounding box information.

DETAILS

pstotext does its work by telling Ghostscript to load a PostScript library that causes it
to write to its standard output information about each string rendered by a PostScript job
or PDF document. This information includes the characters of the string, and enough
additional information to approximate the string's bounding rectangle. pstotext
post-processes this information and outputs a sequence of words delimited by space,
newline, and formfeed.

pstotext outputs words in the same sequence as they are rendered by the document. This
usually, but not always, follows the order that a human would read the words on a page.
Within this sequence, words are separated by either space or newline depending on whether
or not they fall on the same line. Each page is terminated with a formfeed. If you use
the incorrect option from the set {-portrait, -landscape, -landscapeOther}, pstotext is
likely to substitute newline for space.

A PostScript job or PDF document often renders one word as several strings in order to get
correct spacing between particular pairs of characters. pstotext does its best to
assemble these strings back into words, using a simple heuristic: strings separated by a
distance of less than 0.3 times the minimum of the average character widths in the two
strings are considered to be part of the same word. Note that this typically causes
leading and trailing punctuation characters to be included with a word.

The PostScript language provides a flexible encoding scheme by which character codes in
strings select specific characters (symbols), so a PostScript job is free to use any
character code. On the other hand, pstotext always translates to the ISO 8859-1 (Latin-1)
character code, which is an extension to ASCII covering most of the Western European
languages. When a character isn't present in ISO 8859-1, pstotext uses a sequence of
characters, e.g., "---" for em dash or "A\226" for Abreve. pstotext can be fooled by a
font whose Encoding vector doesn't follow Adobe's conventions, but it contains heuristics
allowing it to handle a wide variety of misbehaving fonts.

(pstotext no longer translates hyphen (\255) to minus (\055).)

AUTHOR

       Andrew Birrell (PostScript libraries), Paul McJones (application), Russell  Lang  (Windows
       and OS/2 adaptation), and Hunter Goatley (VMS adaptation).

COPYRIGHT