16 Optional Content Groups

cpdf -ocg-list in.pdf

cpdf -ocg-rename -ocg-rename-from <a> -ocg-rename-to <b> in.pdf -o out.pdf

cpdf -ocg-order-all in.pdf -o out.pdf

cpdf -ocg-coalesce-on-name in.pdf -o out.pdf

In a PDF file, optional content groups are used to group graphical elements together, so they may appear or not, depending on the preference of the user. They are similar in some ways to layers in graphics illustration programs.

List the optional content groups in the PDF, one per line, to standard output. UTF8.

cpdf -ocg-rename -ocg-rename-from <a> -ocg-rename-to <b> in.pdf -o out.pdf

Coalesce optional content groups. For example, if we merge or stamp two files both with an OCG called ”Layer 1”, we will have two different optional content groups. Running -ocg-coalesce-on-name will merge the two into a single optional content group.

Python Interface

# CHAPTER 16. Optional Content Groups

def getOCGList(pdf):
    """Return a list of Optional Content Groups in the given pdf as strings."""

def OCGRename(pdf, n_from, n_to):
    """Rename an optional content group."""

def OCGOrderAll(pdf):
    """Ensure that every optional content group appears in the OCG order list."""

def OCGCoalesce(pdf):
    """Coalesce optional content groups. For example, if we merge or stamp two
    files both with an OCG called "Layer 1", we will have two different
    optional content groups. This function will merge the two into a single
    optional content group."""

Chapter 16Optional Content Groups

Python Interface

Chapter 16
Optional Content Groups