Perl Requires Chilkat v11.7.0+

Extract Text from a Two-Column PDF

See more PDF Text Extraction Examples

Demonstrates how multi-column pages are read. By default the columns are detected and each column is read top to bottom before the next ("columns": "auto"); "columns": "none" reads the full page width line by line, which interleaves the columns. The quality report tells how many columns were found. Chilkat2 Perl

use strict;
use warnings;
use Chilkat2;

# This example requires the Chilkat API to have been previously unlocked.
# See Global Unlock Sample for sample code.

# The two-column PDF used in this example is available at two_column_article.pdf

my $pdf = Chilkat2::Pdf->new;
my $success = $pdf->LoadFile('qa_data/pdf/two_column_article.pdf');
if (!$success) {
    print $pdf->LastErrorText, "\n";
    exit;
}

my $json = Chilkat2::JsonObject->new;
my $jsonOut = Chilkat2::JsonObject->new;

# With the default options the columns are detected, and the text of the left column
# comes before the text of the right column.
$success = $pdf->ExtractText('text', $json, $jsonOut);
if (!$success) {
    print $pdf->LastErrorText, "\n";
    exit;
}

print 'Columns detected: ', $jsonOut->IntOf('quality.pages[0].columns'), "\n";
print 'Reading order: ', $jsonOut->StringOf('quality.pages[0].readingOrderSource'), "\n";
print $jsonOut->StringOf('text'), "\n";

# "none" switches column detection off: the page is read across its full width, line by line,
# so each output line holds a line of the left column followed by a line of the right column.
# This is rarely wanted, but it shows what the detection does.
$json->UpdateString('columns', 'none');
$json->UpdateString('layout', 'lines');
$success = $pdf->ExtractText('text', $json, $jsonOut);
if (!$success) {
    print $pdf->LastErrorText, "\n";
    exit;
}

print "---- columns: none ----\n";
print $jsonOut->StringOf('text'), "\n";

# Sample output (abbreviated):

# Columns detected: 2
# Reading order: visual
# The Harbor Lighthouse, Season Two
#
# The harbor lighthouse was built in 1874 to mark the entrance to the inner channel. It operated continuously until 1968, ...
#
# The restoration society took ownership in 2021 with three goals: ...
# ...
# The lantern room frame was stripped, primed and repainted in the original dark green. ...
# ...
# ---- columns: none ----
# The Harbor Lighthouse, Season Two
# The harbor lighthouse was built in 1874 to The lantern room frame was stripped, primed
# mark the entrance to the inner channel. It and repainted in the original dark green. New
# ...