PHP ActiveX

PDF Signature with Background Image (Seal/Stamp/etc.)

See more PDF Signatures Examples

Demonstrates how to sign a PDF with an appearance that includes a background image, such as a seal, stamp, etc.

Note: This example requires Chilkat v9.5.0.85 or greater.

PHP ActiveX

<?php

$success = 0;

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

$pdf = new COM("Chilkat.Pdf");

//  Load a PDF to be signed.
//  The "hello.pdf" is available at https://chilkatsoft.com/hello.pdf
$success = $pdf->LoadFile('qa_data/pdf/hello.pdf');
if ($success == 0) {
    print $pdf->LastErrorText . "\n";
    exit;
}

//  Options for signing are specified in JSON.
$json = new COM("Chilkat.JsonObject");

//  In most cases, the signingCertificateV2 and signingTime attributes are required.
$json->UpdateInt('signingCertificateV2',1);
$json->UpdateInt('signingTime',1);

//  Put the signature on page 1, top left
$json->UpdateInt('page',1);
$json->UpdateString('appearance.y','top');
$json->UpdateString('appearance.x','left');

//  Use a font scale of 10.0
$json->UpdateString('appearance.fontScale','10.0');

//  In this example, the appearance of the digital signature will contain three lines:
//  1) The signing certificate's common name
//  2) The current date/time
//  3) Some arbitrary text.
//  The keyword "cert_cn" is replaced with the Certificate's Subject Common Name.
//  The keyword "current_dt" is replaced with the current date/time.
//  Any number of appearance text lines can be added.
$json->UpdateString('appearance.text[0]','Digitally signed by: cert_cn');
$json->UpdateString('appearance.text[1]','current_dt');
$json->UpdateString('appearance.text[2]','The crazy brown fox jumps over the lazy dog.');

//  Load a JPG image to be shown with 30% opacity in the background.
//  (the image must be in the JPG format)
//  The sample university.jpb is available at https://example-code.com/images/university.jpg

$jpgData = new COM("Chilkat.BinData");
$success = $jpgData->LoadFile('qa_data/jpg/university.jpg');
if ($success == 0) {
    print 'Failed to load the JPG image.' . "\n";
    exit;
}

$success = $pdf->SetSignatureJpeg($jpgData);
if ($success == 0) {
    print $pdf->LastErrorText . "\n";
    exit;
}

//  Specify that we want to display the JPG image in the center with 30% opacity.
$json->UpdateString('appearance.image','custom-jpg');
$json->UpdateString('appearance.imagePlacement','center');
$json->UpdateString('appearance.imageOpacity','30');

//  Load the signing certificate. (Use your own certificate.)
$cert = new COM("Chilkat.Cert");
$success = $cert->LoadPfxFile('qa_data/pfx/myPdfSigningCert.pfx','secret');
if ($success == 0) {
    print $cert->LastErrorText . "\n";
    exit;
}

//  Tell the pdf object to use the certificate for signing.
$success = $pdf->SetSigningCert($cert);
if ($success == 0) {
    print $pdf->LastErrorText . "\n";
    exit;
}

$success = $pdf->SignPdf($json,'qa_output/hello_signed.pdf');
if ($success == 0) {
    print $pdf->LastErrorText . "\n";
    exit;
}

print 'The PDF has been successfully cryptographically signed.' . "\n";

//  The appearance of the signature appears in Adobe Acrobat as shown below.
//  The JPG is automatically scaled to the size of the signature based on the signature's font scale
//  and number of text lines.
//  

?>