PDF Layers are called Optional Content within the PDF specifications. This is a feature that was added as of PDF-1.5 (Acrobat 6.) A layer is identified by an identifier and a title. Only the layer’s title is visible to the end-user of the PDF document. Layers can be structured as a tree or a hierarchy of layers.
Amyuni PDF Creator allows the creation and visualization of layers in any PDF file using :
ACPDFCREACTIVEX.PDFCreactiveX interface included in Amyuni PDF CreativeX Component(PDFCreactiveX.DLL), or
AxacLayersCtrl control part of Amyuni PDF Creator Extension controls(acPDFCrExt.DLL)