PHP - Fallo con input

<!-- Modal insertar -->

<div class="modal fade" id="agregarnuevosdatosmodal" tabindex="-1" role="dialog" aria-labelledby="exampleModalLabel" aria-hidden="true">

  <div class="modal-dialog" role="document">

    <div class="modal-content">

      <div class="modal-header">

        <h5 class="modal-title" id="exampleModalLabel">Nueva noticia</h5>

        <button type="button" class="close" data-dismiss="modal" aria-label="Close">

          <span aria-hidden="true">&times;</span>

        </button>

      </div>

      <div class="modal-body">

            <form id="frmnuevanoticia" accept-charset="utf-8" enctype="multipart/form-data">

                <label>Título</label>

                <input type="text" class="form-control input-sm" name="titulo" id="titulo">

                <label>Noticia</label>

                <textarea class="form-control input-sm" id="noticia" name="noticia" rows="7"></textarea>

                <label>Fecha</label>

                <input type="date" class="form-control input-sm" name="fecha" id="fecha">

                <label>Autor</label>

                <input type="text" class="form-control input-sm" name="autor" id="autor">

                <label>Imagen</label>

                <input type="file" class="form-control input-sm" name="imagen" id="imagen" accept="image/*">

            </form>

      </div>

      <div class="modal-footer">

        <button type="button" class="btn btn-secondary" data-dismiss="modal">Cerrar</button>

        <button type="button" id="btnAgregarnoticia" class="btn btn-primary">Agregar nueva</button>

      </div>

    </div>

  </div>

</div>

$(document).ready(function(){

        $("#btnAgregarnoticia").on('click', function(e) {

          e.preventDefault();

        var form = $('#frmnuevanoticia')[0];

        var data = new FormData(form);

        $.ajax({

            url: 'procesos/agregar.php',

            type: 'post',

            data: data,

            cache: false,

            contentType: false,

            processData: false,

            success: function(r) {

              if (r==1){

                        $('#frmnuevo')[0].reset();

                        $('#tablaDatatable').load('procesos/tabla.php');

                        alertify.success("Agregada con éxito");

                    }else{

                        alertify.error("Error al agregar");

                    }

            }

        });

        return false;

    });

});

<?php

require_once "../clases/conexion.php";

require "../clases/crud.php";

     $obj= new crud();

     if (($_FILES["imagen"]["type"] == "image/pjpeg")

    || ($_FILES["imagen"]["type"] == "image/jpeg")

    || ($_FILES["imagen"]["type"] == "image/png")

    || ($_FILES["imagen"]["type"] == "image/gif")) {

        if (move_uploaded_file($_FILES["imagen"]["tmp_name"], "../images/noticias/".$_FILES['imagen']['name'])) {

            $datos=array(

                $_POST['titulo'],

                $_POST['noticia'],

                $_POST['fecha'],

                $_POST['autor'],

                $_FILES['imagen']['name']

     );

     echo $obj->agregar($datos);

    }

}

?>