Someone has some idea of how to add a signature to an existing pdf file with php. I have a laboratory system where analysis results are stored in pdf format and I need to insert in the file signatures that I have in image format so that the results are valid.
How can it be done?
Even though your question requires research work, I'll leave you with an answer because I found your question interesting.
Based on this answer ( Insert images in PDF file using PHP ) ( Insert image files in an existing PDF using PHP ) of SOen and this other link , you can use the following libraries FPDF and FPDI as follows (very simple example):
require_once('fpdf.php'); // Incluímos las librerías anteriormente mencionadas
require_once('fpdi.php'); // Incluímos las librerías anteriormente mencionadas
$pdf = new FPDI();
$pdf->AddPage();
$pdf->setSourceFile("Ruta_de_mi_archivo_PDF"); // Sin extensión
$template = $pdf->importPage(1);
$pdf->useTemplate($template);
$pdf->Image('Ruta_de_mi_imagen.jpg', $x, $y, $width, $height);
$pdf->Output($nuevoNombreDelPDF, "F");
Where the variables $x and $y are the coordinates where to put the image inside your PDF, $width and $height are the width and the height respectively and finally the variable $nuevoNombreDelPDF that will be the name of our "new" PDF
You can use the FPDF class for PHP, which is responsible for generating PHP files and the FPDI class that can be used to import files or pages of pre-existing PDF files.
Take a look at this