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PDF Rendering Server

To render pages in a document, post a multipart request to the [/api/build API endpoint][], including the desired page index or indexes in the instructions.output.pages field. To learn more about the schema for /build instructions, go to the API Reference.

In the /api/build request, set the instructions.output.type parameter to image. By default, the output.type for /build instructions is set to pdf. The page index is provided via the instructions.output.pages field, and the rendered dimensions are provided via a width, height, or dpi option.

To learn more about available options for rendering, go to the API Reference.

Only one option — width, height, or dpi — can be chosen. Other dimensions are calculated before rendering, so as to preserve the page aspect ratio of the rendered image.

The format of the rendered image can be controlled via the format option. Supported image formats are PNG, JPEG, WEBP, and TIFF.

For more information, refer to the API reference to learn about the /api/build endpoint and all the actions you can perform on PDFs with Document Engine.

For an overview of multipart requests, refer to the brief tour of multipart requests blog post.

Rendering a Page of a File on Disk

You can render a single page or multiple pages of a document.

Rendering a Single Page

The following example renders the second page (with index 1) of a document. The response to this request is a PNG image file:

curl -X POST http://localhost:5000/api/build \
  -H "Authorization: Token token=<API token>" \
  -F document=@/path/to/example-document.pdf \
  -F instructions='{
  "parts": [
    {
      "file": "document"
    }
  ],
  "output": {
    "type": "image",
    "format": "png",
    "pages": {
      "start": 1,
      "end": 1
    }
  }
}' \
  -o output-image.png
POST /api/build HTTP/1.1
Content-Type: multipart/form-data; boundary=customboundary
Authorization: Token token=<API token>

--customboundary
Content-Disposition: form-data; name="document"; filename="example-document.pdf"
Content-Type: application/pdf

<PDF data>
--customboundary
Content-Disposition: form-data; name="instructions"
Content-Type: application/json

{
  "parts": [
    {
      "file": "document"
    }
  ],
  "output": {
    "type": "image",
    "format": "png",
    "pages": {
      "start": 1,
      "end": 1
    }
  }
}
--customboundary--

Rendering Multiple Pages

The following example renders the first, second, and third page (indexes 0, 1 and 2) of a document. The response to this request is a ZIP file containing all the images:

curl -X POST http://localhost:5000/api/build \
  -H "Authorization: Token token=<API token>" \
  -F document=@/path/to/example-document.pdf \
  -F instructions='{
  "parts": [
    {
      "file": "document"
    }
  ],
  "output": {
    "type": "image",
    "format": "png",
    "pages": {
      "start": 0,
      "end": 2
    }
  }
}' \
  -o result.zip
POST /api/build HTTP/1.1
Content-Type: multipart/form-data; boundary=customboundary
Authorization: Token token=<API token>

--customboundary
Content-Disposition: form-data; name="document"; filename="example-document.pdf"
Content-Type: application/pdf

<PDF data>
--customboundary
Content-Disposition: form-data; name="instructions"
Content-Type: application/json

{
  "parts": [
    {
      "file": "document"
    }
  ],
  "output": {
    "type": "image",
    "format": "png",
    "pages": {
      "start": 0,
      "end": 2
    }
  }
}
--customboundary--

Rendering a Page of a File from a URL

You can specify the document to render by providing a URL to the document instead of a path to the file:

curl -X POST http://localhost:5000/api/build \
  -H "Authorization: Token token=<API token>" \
  -F instructions='{
  "parts": [
    {
      "file": {
        "url": "https://pspdfkit.com/downloads/examples/paper.pdf"
      }
    }
  ],
  "output": {
    "type": "image",
    "format": "png",
    "pages": {
      "start": 1,
      "end": 1
    }
  }
}' \
  -o output-image.png
POST /api/build HTTP/1.1
Content-Type: multipart/form-data; boundary=customboundary
Authorization: Token token=<API token>

--customboundary
Content-Disposition: form-data; name="instructions"
Content-Type: application/json

{
  "parts": [
    {
      "file": {
        "url": "https://pspdfkit.com/downloads/examples/paper.pdf"
      }
    }
  ],
  "output": {
    "type": "image",
    "format": "png",
    "pages": {
      "start": 1,
      "end": 1
    }
  }
}
--customboundary--