Null error on ImageRezising.net Faces plugin

Question

I'm testing the faces plugin: http://imageresizing.net/docs/v4/plugins/faces

But I'm only getting the response "Object reference not set to an instance of an object.". Why? From the look of it the error is from the ImageRezing.net software.

Here is an example to see the error: http://azure.content.dev.bloc.net/azure/group/200000206/5319/2018/10/10/20150406145944-dos-donts-taking-perfect-linkedin-profile-picture-selfie-mobile-camera-2.jpeg?f.detect=true

Exception information:

Exception type: NullReferenceException

Exception message: Object reference not set to an instance of an object.

at ImageResizer.Plugins.Faces.FeatureDetectionBase`1.Dispose() at ImageResizer.Plugins.Faces.FacesPlugin.PostPrepareSourceBitmap(ImageState s) at ImageResizer.Resizing.AbstractImageProcessor.PostPrepareSourceBitmap(ImageState s) at ImageResizer.ImageBuilder.Process(ImageState s) at ImageResizer.ImageBuilder.BuildJobBitmapToBitmap(ImageJob job, Bitmap source, Boolean transparencySupported) at ImageResizer.ImageBuilder.BuildJobBitmapToStream(ImageJob job, Bitmap source, Stream dest) at ImageResizer.ImageBuilder.BuildJob(ImageJob job) at ImageResizer.ImageBuilder.Build(ImageJob job) at ImageResizer.InterceptModule.<>c__DisplayClass5_0.b__1(Stream stream) at ImageResizer.Plugins.DiskCache.CustomDiskCache.<>c__DisplayClass29_0.b__0() at ImageResizer.Plugins.DiskCache.LockProvider.TryExecute(String key, Int32 timeoutMs, LockCallback success) at ImageResizer.Plugins.DiskCache.CustomDiskCache.GetCachedFile(String keyBasis, String extension, ResizeImageDelegate writeCallback, Int32 timeoutMs, Boolean asynchronous) at ImageResizer.Plugins.DiskCache.DiskCache.Process(IResponseArgs e) at ImageResizer.Plugins.DiskCache.DiskCache.Process(HttpContext context, IResponseArgs e) at ImageResizer.InterceptModule.HandleRequest(HttpContext context, HttpModuleRequestAssistant ra, IVirtualFile vf) at ImageResizer.InterceptModule.CheckRequest_PostAuthorizeRequest(Object sender, EventArgs e) at System.Web.HttpApplication.SyncEventExecutionStep.System.Web.HttpApplication.IExecutionStep.Execute() at System.Web.HttpApplication.ExecuteStepImpl(IExecutionStep step) at System.Web.HttpApplication.ExecuteStep(IExecutionStep step, Boolean& completedSynchronously)

Global.asax has nothing:

using ImageResizer.Plugins.RemoteReader;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.Security;
using System.Web.SessionState;

namespace Bloc.AzureContent
{
    public class Global : System.Web.HttpApplication
    {

        protected void Application_Start(object sender, EventArgs e)
        {
            RemoteReaderPlugin.Current.AllowRemoteRequest += Current_AllowRemoteRequest;
        }

        static void Current_AllowRemoteRequest(object sender, RemoteRequestEventArgs args)
        {
            args.DenyRequest = false;
        }

        protected void Session_Start(object sender, EventArgs e)
        {

        }

        protected void Application_BeginRequest(object sender, EventArgs e)
        {

        }

        protected void Application_AuthenticateRequest(object sender, EventArgs e)
        {

        }

        protected void Application_Error(object sender, EventArgs e)
        {

        }

        protected void Session_End(object sender, EventArgs e)
        {

        }

        protected void Application_End(object sender, EventArgs e)
        {

        }
    }
}