code: function(outname, imagedata) {
          var frames = [];
          var animations = {};
  
          // first pass: set up frame for each image, ensure an animation array is present
          imagedata.forEach(function(im) {
              var ox = Math.floor(im.width / 2);
              var oy = Math.floor(im.height / 2);
              im.frame = frames.length;
              frames.push([im.x, im.y, im.width, im.height, 0, im.ox, im.oy]);
              if(!animations[im.animname]) {
                  animations[im.animname] = { frames: [] };
              }
          });
  
          // re-sort the images to frame order and then push their frame indices
          // into the respective arrays.
          imagedata.sort(function(a, b) { return a.animidx - b.animidx; });
          imagedata.forEach(function(im) {
              animations[im.animname].frames.push(im.frame);
          });
  
          // put all the data in its appropriate groups and JSONify
          var data = {
              frames: frames,
              animations: animations,
              images: [ outname + ".png" ]
          };
          return JSON.stringify(data, null, 2);
      }
docs: format for CreateJS framework