Perl Requires Chilkat v11.7.0+

QR Code Colors and Transparent Background

See more QR Code Examples

Demonstrates colored QR codes. render.foreground is the color of the dark modules and render.background the color behind them, each as #RRGGBB. Either can instead be an object with a color and an opacity from 0 to 1, and a background opacity of 0 gives a PNG with a transparent background to place over a page or a design. Readers need contrast: keep the modules clearly darker than whatever ends up behind them. 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.

my $fmt = Chilkat2::Formats->new;
my $jsonOut = Chilkat2::JsonObject->new;

# Dark blue modules on a pale yellow background.
my $json = Chilkat2::JsonObject->new;
$json->UpdateString('payload.text', 'https://www.chilkatsoft.com/');
$json->UpdateInt('render.moduleSize', 6);
$json->UpdateString('render.foreground', '#1B3A6B');
$json->UpdateString('render.background', '#FFF8DC');
$json->UpdateString('output.path', 'qa_output/qr_blue.png');
$json->UpdateBool('output.overwrite', 1);
$json->UpdateString('output.return', 'none');
my $success = $fmt->QrCode('generate', $json, $jsonOut);
if (!$success) {
    print $fmt->LastErrorText, "\n";
    exit;
}

print 'colored: ', $jsonOut->StringOf('outputs[0].path'), ', ', $jsonOut->IntOf('outputs[0].byteCount'), " bytes\n";

# The image written to qa_output/qr_blue.png:

# 

# The same modules on a fully transparent background.
my $json2 = Chilkat2::JsonObject->new;
$json2->UpdateString('payload.text', 'https://www.chilkatsoft.com/');
$json2->UpdateInt('render.moduleSize', 6);
$json2->UpdateString('render.foreground', '#1B3A6B');
$json2->UpdateString('render.background.color', '#FFFFFF');
$json2->UpdateNumber('render.background.opacity', '0');
$json2->UpdateString('output.path', 'qa_output/qr_transparent.png');
$json2->UpdateBool('output.overwrite', 1);
$json2->UpdateString('output.return', 'none');
$success = $fmt->QrCode('generate', $json2, $jsonOut);
if (!$success) {
    print $fmt->LastErrorText, "\n";
    exit;
}

print 'transparent: ', $jsonOut->StringOf('outputs[0].path'), ', ', $jsonOut->IntOf('outputs[0].byteCount'), " bytes\n";

# qa_output/qr_transparent.png, placed here over a checkerboard and over a colored page
# to show that whatever is behind the image shows through:

# 

# Sample output:

# colored: qa_output/qr_blue.png, 1345 bytes
# transparent: qa_output/qr_transparent.png, 1377 bytes