= JSON annotation format =

The [[http://en.wikipedia.org/wiki/JSON|JSON]] format for annotations is based on the [[https://github.com/okfn/annotator/wiki/Storage|Annotator Store API]].

== Image areas ==

Annotations of image areas have a "shapes" member, specifying a list of shapes on the image. The shape definitions are based on the [[http://www.w3.org/TR/SVG/shapes.html|SVG shape definitions]]. 

The possible shape forms are
  * point
  * rectangle
  * polygon (not yet implemented)
  * circle (not yet implemented)

Coordinates and coordinate units are specified in a "geometry" member. 

The coordinate unit "fraction" means that each coordinate is specified as a decimal fraction (float 0 <= x <= 1) of the image side length, e.g. x=0.03 means that x is at 3% of the total image width.

Example of an image area specification:
{{{
"shapes" : [{
  "type" : "rectangle",
  "geometry" : {
    "units" : "fraction",
    "x" : 0.0123,
    "y": 0.345,
    "width" : 0.567,
    "height": 0.789
  }
}]
}}}