Add background image to invoice

Hello,

I want to add a background image to the invoice. I checked the pdfmake.org/playground and managed to this:

var dd = {
    background: [
    {
       image: 'data:image/jpeg;base64,/9j/4RC...image...',
       width: 595
    }
    ],
	content: [
		'pdfmake (since it\'s based on pdfkit) supports JPEG and PNG format',
		
	],
}

But how will I be able to add this to the template?

I tried this below, but it gives me an error:

[
  {
    "background": [
      {
        "image": "$accountLogo",
        "width": 300
      }
    ]
  },
  {
    "columns": [
      {
        "image": "$accountLogo",
        "fit": [
          120,
          80
        ]
      },
....

Error:

Uncaught Unrecognized document structure: {"background":[{"image":"data:image/jpeg;base64,iVBORw0KGgoAAAANSUhEUgAAA2cAAAHdCAYAAACZhQFfAAAgAElEQVR4nOzde5gc

This isn’t currently supported. The invoice design editor sets the value for the PDF content, however the value for background is set outside of the content value.

It’d be a good feature, I’ve added it to our roadmap: https://trello.com/c/dUohfkMH