Reading PDF Annotations

PDF 2.0 defines the following annotation types:

• Text

• Link

• FreeText

• Line

• Square

• Circle

• Polygon

• PolyLine

• Highlight

• Underline

• Squiggly

• StrikeOut

• Caret

• Stamp

• Ink

• Popup

• FileAttachment

• Sound

• Movie

• Screen

• Widget

• PrinterMark

• TrapNet

• Watermark

• 3D

• Redact

• Projection

• RichMedia

In general, annotations can be read like this:

from pypdf import PdfReader

reader = PdfReader("annotated.pdf")

for page in reader.pages:
    if "/Annots" in page:
        for annot in page["/Annots"]:
            obj = annot.get_object()
            annotation = {"subtype": obj["/Subtype"], "location": obj["/Rect"]}
            print(annotation)

Examples of reading three of the most common annotations:

Text

from pypdf import PdfReader

reader = PdfReader("example.pdf")

for page in reader.pages:
    if "/Annots" in page:
        for annot in page["/Annots"]:
            subtype = annot.get_object()["/Subtype"]
            if subtype == "/Text":
                print(annot.get_object()["/Contents"])

Highlights

from pypdf import PdfReader

reader = PdfReader("example.pdf")

for page in reader.pages:
    if "/Annots" in page:
        for annot in page["/Annots"]:
            subtype = annot.get_object()["/Subtype"]
            if subtype == "/Highlight":
                coords = annot.get_object()["/QuadPoints"]
                x1, y1, x2, y2, x3, y3, x4, y4 = coords

Attachments

from pypdf import PdfReader

reader = PdfReader("example.pdf")

attachments = {}
for page in reader.pages:
    if "/Annots" in page:
        for annotation in page["/Annots"]:
            subtype = annot.get_object()["/Subtype"]
            if subtype == "/FileAttachment":
                fileobj = annotobj["/FS"]
                attachments[fileobj["/F"]] = fileobj["/EF"]["/F"].get_data()