if (!$doc->HasOC()) {
echo nl2br("The document does not contain 'Optional Content'\n");
} else {
$init_cfg = $doc->GetOCGConfig();
$ctx = new Context($init_cfg);
$pdfdraw = new PDFDraw();
$pdfdraw->SetImageSize(1000, 1000);
$pdfdraw->SetOCGContext($ctx);
// Render the page using the given OCG context.
$page = $doc->GetPage(1);
// Get the first page in the document.
$pdfdraw->Export($page, $output_path . "pdf_layers_default.png");
// Disable drawing of content that is not optional (i.e. is not part of any layer).
$ctx->SetNonOCDrawing(false);
// Now render each layer in the input document to a separate image.
$ocgs = $doc->GetOCGs();
// Get the array of all OCGs in the document.
if ($ocgs != null) {
$sz = $ocgs->Size();
for ($i = 0; $i < $sz; ++$i) {
$ocg = new Group($ocgs->GetAt($i));
$ctx->ResetStates(false);
$ctx->SetState($ocg, true);
$fname = $output_path . "pdf_layers_" . $ocg->GetName() . ".png";
echo nl2br($fname . "\n");
$pdfdraw->Export($page, $fname);
}
}
// Now draw content that is not part of any layer...
$ctx->SetNonOCDrawing(true);
$ctx->SetOCDrawMode(Context::e_NoOC);
