FARBFELD IMAGE FORMAT SPECIFICATION

  +--------+---------------------------------------------------------+
  | Bytes  | Description                                             |
  +--------+---------------------------------------------------------+
  | 8      | "farbfeld" magic value                                  |
  +--------+---------------------------------------------------------+
  | 4      | 32-Bit BE unsigned integer (width)                      |
  +--------+---------------------------------------------------------+
  | 4      | 32-Bit BE unsigned integer (height)                     |
  +--------+---------------------------------------------------------+
  | [2222] | 4*16-Bit BE unsigned integers [RGBA] / pixel, row-major |
  +--------+---------------------------------------------------------+