NAME

PDF::Make::Filter - Perl access to PDF stream filters (Flate, ASCII85, LZW, etc.)

SYNOPSIS

use PDF::Make::Filter;

my $encoded = PDF::Make::Filter::flate_encode("hello world");
my $plain   = PDF::Make::Filter::flate_decode($encoded);

my $a85 = PDF::Make::Filter::ascii85_encode("Man is distinguished");
my $raw = PDF::Make::Filter::ascii85_decode($a85);

my $rle = PDF::Make::Filter::rle_encode("AAAABBBCC");
my $pred = PDF::Make::Filter::predictor_encode(
    predictor => 12, columns => 4, data => $row_data,
);

DESCRIPTION

Thin wrappers around the XS-exposed PDF stream filter implementations from libpdfmake. Intended primarily for unit testing.

FUNCTIONS

ascii85_encode, ascii85_decode

ASCII-85 codec (§7.4.3). Output of encode is terminated with ~>.

asciihex_encode, asciihex_decode

ASCIIHex codec (§7.4.2). Encoded form uses uppercase and terminates with >.

flate_encode, flate_decode

zlib-wrapped DEFLATE codec (§7.4.4).

deflate_encode($bytes, $level), deflate_decode

Raw DEFLATE codec (RFC 1951). $level is 0-9, default 6.

adler32($bytes)

Adler-32 checksum (RFC 1950).

lzw_decode($bytes, early_change => 1)

LZW decoder (§7.4.4).

predictor_encode / predictor_decode

PNG predictors (10-15) with predictor, colors, bits, columns, and data keyword args.

tiff_predictor_encode / tiff_predictor_decode

TIFF predictor 2 (horizontal differencing).

SEE ALSO

PDF::Make