1Text::PDF::Filter(3) User Contributed Perl Documentation Text::PDF::Filter(3)
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6 PDF::Filter - Abstract superclass for PDF stream filters
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9 $f = Text::PDF::Filter->new;
10 $str = $f->outfilt($str, 1);
11 print OUTFILE $str;
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13 while (read(INFILE, $dat, 4096))
14 { $store .= $f->infilt($dat, 0); }
15 $store .= $f->infilt("", 1);
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18 A Filter object contains state information for the process of
19 outputting and inputting data through the filter. The precise state
20 information stored is up to the particular filter and may range from
21 nothing to whole objects created and destroyed.
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23 Each filter stores different state information for input and output and
24 thus may handle one input filtering process and one output filtering
25 process at the same time.
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28 Text::PDF::Filter->new
29 Creates a new filter object with empty state information ready for
30 processing data both input and output.
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32 $dat = $f->infilt($str, $isend)
33 Filters from output to input the data. Notice that $isend == 0 implies
34 that there is more data to come and so following it $f may contain
35 state information (usually due to the break-off point of $str not being
36 tidy). Subsequent calls will incorporate this stored state information.
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38 $isend == 1 implies that there is no more data to follow. The final
39 state of $f will be that the state information is empty. Error messages
40 are most likely to occur here since if there is required state
41 information to be stored following this data, then that would imply an
42 error in the data.
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44 $str = $f->outfilt($dat, $isend)
45 Filter stored data ready for output. Parallels "infilt".
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48 Text::PDF::ASCII85Decode - Ascii85 filter for PDF streams. Inherits
49 from Text::PDF::Filter
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52 Text::PDF::RunLengthDecode - Run Length encoding filter for PDF
53 streams. Inherits from Text::PDF::Filter
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56 Text::PDF::ASCIIHexDecode - Ascii Hex encoding (very inefficient) for
57 PDF streams. Inherits from Text::PDF::Filter
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61perl v5.34.0 2021-07-23 Text::PDF::Filter(3)