How to set the OCG state of an existing PDF?

I need to turn off a specific layer (OCG object) in an existing PDF that was created in AutoCAD and that sets the default value to "on". How can I change this to "off"?

Posted on StackOverflow on May 1, 2014 by HoustonVBnovice

I've created an example that turns off the visibility of a specific layer. See ChangeOCG.

The concept is really simple. You already have a PdfReader object and you want to apply a change to a file. As documented, you create a PdfStamper object. As you want to change an OCG layer, you use the getPdfLayers() method and you select the layer you want to change by name. (In my example, the layer I want to turn off is named "Nested layer 1"). You use the setOn() method to change its status, and you're done:

JAVA

PdfReader reader = new PdfReader(src);
PdfStamper stamper = new PdfStamper(reader, new FileOutputStream(dest));
Map layers = stamper.getPdfLayers();
PdfLayer layer = layers.get("Nested layer 1");
layer.setOn(false);
stamper.close();
reader.close();

This is Java code. Please read it as if it were pseudo-code and adapt it to your language of choice.