Add ink annotations to PDFs in Java

Annotations are created using the AnnotationProvider.AddAnnotationJson method. To create an annotation on a page, use the annotation JSON format to add the annotation you want.

Creating ink annotations

An ink annotation consists of a series of x,y coordinate Points (in pixels) starting from the top left of the page. Each point has a corresponding Intensity with a value from 0.0 to 1.0 (the default is 0.5).

Here’s an example of adding an ink annotation with JSON:

{
  "id": "10",
  "v": 1,
  "pdfObjectId": 10,
  "pageIndex": 0,
  "bbox": [0, 0, 700, 900],
  "opacity": 1,
  "type": "pspdfkit/ink",
  "lines": {
    "points": [
      [
        [445.5, 503.9],
        [438.6, 503.1],
        [433.4, 500.5],
        [267.5, 435.2]
      ]
    ],
    "intensities": [[0.5, 0.5, 0.5, 0.5]]
  },
  "lineWidth": 5,
  "strokeColor": "#2483c7",
  "isDrawnNaturally": false,
  "isSignature": false
}

The JSON can be loaded from a file and added using addAnnotationJson:

String jsonString = Files.readAllBytes(Paths.get("path/to/my-annotation.json")).toString();
document.getAnnotationProvider().addAnnotationJson(new JSONObject(jsonString));