PDF and dynamic PNG

Hello, I succeed in creating PDF files dynamically with PHP (including inserting static PNG images), and also succeed in creating PNG images dynamically. However, I can't insert dynamically created PNG images into PDF files, neither with pdf_open_image_file, nor with pdf_open_png. Is this impossible? D o m i n i k Example: function putimage ($pdf, $fullfilename, $x, $y, $width) { // init $extension = substr($fullfilename, strrpos ($fullfilename, ".")+1); $pdfimage = pdf_open_image_file($pdf, $extension, $fullfilename); // define scale $sourceimagewidth = pdf_get_value ($pdf, "imagewidth", $pdfimage); $scale = $width / $sourceimagewidth; // put image pdf_place_image($pdf, $pdfimage, $x, $y, $scale); }