Chapter 10

cpdf -list-annotations in.pdf [<range>]

cpdf -list-annotations-json in.pdf [<range>]

cpdf -copy-annotations from.pdf to.pdf [<range>] -o out.pdf

cpdf -remove-annotations in.pdf [<range>] -o out.pdf

10.1 Listing Annotations

The -list-annotations operation prints the textual content of any annotations on the selected pages to standard output. Each annotation is preceded by the page number and followed by a newline. The output of this operation is always UTF8.

cpdf -list-annotations in.pdf > annots.txt

Print annotations from in.pdf, redirecting output to annots.txt.

More information can be obtained by listing annotations in JSON format:

cpdf -list-annotations-json in.pdf > annots.json

Print annotations from in.pdf in JSON format, redirecting output to annots.json.

This produces an array of (page number, annotation) pairs giving the PDF structure of each annotation. Destination pages for page links will have page numbers in place of internal PDF page links, and certain indirect objects are made direct but the content is otherwise unaltered. Here is an example entry for an annotation on page 10:

  { "/H": { "N": "/I" },
    "/Border": [ { "I": 0 }, { "I": 0 }, { "I": 0 } ],
    "/Rect": [
      { "F": 89.88023 }, { "F": 409.98401 }, { "F": 323.90561 }, {
        "F": 423.32059 } ],
    "/Subtype": { "N": "/Link" },
    "/Type": { "N": "/Annot" },
    "/A": {
      "/S": { "N": "/URI" },
      "/URI": "" },
    "/StructParent": { "I": 10 } } ]

A future version of cpdf will allow these JSON annotations to be edited and re-loaded into a PDF file.

10.2 Copying Annotations

The -copy-annotations operation copies the annotations in the given page range from one file (the file specified immediately after the option) to another pre-existing PDF. The range is specified after this pre-existing PDF. The result is then written an output file, specified in the usual way.

cpdf -copy-annotations from.pdf to.pdf 1-10 -o result.pdf 

Copy annotations from the first ten pages of from.pdf onto the PDF file to.pdf, writing the result to results.pdf.

10.3 Removing Annotations

The -remove-annotations operation removes all annotations from the given page range.

cpdf -remove-annotations in.pdf 1 -o out.pdf

Remove annotations from the first page of a file only.

C Interface

/* CHAPTER 10. Annotations */ 
/* Return the annotations from a PDF in JSON format, returning also its length. 
void *cpdf_annotationsJSON(int, int *);