NGCordova Instagram Share problem

I have a photo taken as:

$scope.takePhoto = function () {
      var options = {
          quality: 75,è
          destinationType: Camera.DestinationType.DATA_URL,
          sourceType: Camera.PictureSourceType.CAMERA,è
          encodingType: Camera.EncodingType.JPEG,è
          popoverOptions: CameraPopoverOptions,
          saveToPhotoAlbum: true,
          cameraDirection: 1,
          correctOrientation: true

      $cordovaCamera.getPicture(options).then(function(imageData) {

        $scope.imgData = imageData;
        $scope.imgURI = "data:image/jpeg;base64," + imageData;          

      }, function(err) {
        console.error('An error occurred: ' + err);


Then I try to share my photo with

$cordovaInstagram.share($scope.imgData, message).then(function() { console.log('Share ok');

But I got this error:

TypeError: Cannot read property 'slice' of undefined
    at Object.Plugin.share (CDVInstagramPlugin.js:92)
    at Object.share (ng-cordova.min.js:8)
    at Scope.$scope.shareInstagram (app.js:471)
    at fn (eval at <anonymous> (ionic.bundle.js:26457), <anonymous>:4:233)
    at ionic.bundle.js:62386
    at Scope.$eval (ionic.bundle.js:29158)
    at Scope.$apply (ionic.bundle.js:29257)
    at HTMLDivElement.<anonymous> (ionic.bundle.js:62385)
    at HTMLDivElement.n.event.dispatch (jquery-2.2.3.min.js:3)
    at HTMLDivElement.r.handle (jquery-2.2.3.min.js:3)