Cannot get face detection to work

I have looked everywhere to find a working ‘simple’ example of opening the photo viewer selecting a image and using face detection. The code I have so far is this.

void OnMediaPicked(object sender, MediaPickedEventArgs e)
{
   Log("Image picked: " + e.image);

   Texture2D tempTexture = e.image.ToTexture2D();

   FaceDetector faceDetector = new FaceDetector(true, false);

   Face[] features = faceDetector.DetectInImage(tempTexture);

   Debug.Log("features = " + features + " features length= " + features.Length);
}

The output is this:
2014-03-25 22:45:28.224 testApp[444:60b] Unknown CIDetectorTracking specified. Ignoring.
features = U3DXT.iOS.CoreImage.Face features length= 0

My Bad.
Im using U3DXT plugin, here is the code.
using System;
using System.Collections;
using UnityEngine;
using U3DXT.Core;
using U3DXT.iOS.Native.Foundation;
using U3DXT.iOS.Native.UIKit;
using U3DXT.iOS.CoreImage;
using U3DXT.iOS.Native.CoreImage;
using U3DXT.Utils;
using U3DXT.iOS.Native.Internals;
using System.IO;
using System.Text;
using System.Linq;
using U3DXT.iOS.GUI;

public class FaceDetect : MonoBehaviour {

// Use this for initialization
public UITexture scpTexture;
private Face[] features; 
public GUITexture guiTexture;

void Start() {
	if (CoreXT.IsDevice) {
		// subscribes to events
		GUIXT.AlertDismissed += OnAlertDismissed;
		
		GUIXT.MediaPicked += OnMediaPicked;
		GUIXT.MediaPickCancelled += OnMediaCancelled;

	}
}

void OnDestroy() {
	if (CoreXT.IsDevice) {
		// unsubscribe to events
		GUIXT.AlertDismissed -= OnAlertDismissed;
		
		GUIXT.MediaPicked -= OnMediaPicked;
		GUIXT.MediaPickCancelled -= OnMediaCancelled;
	}
}


void OnMediaPicked(object sender, MediaPickedEventArgs e) {
	Log("Image picked: " + e.image);
	
	Texture2D tempTexture = e.image.ToTexture2D();

	FaceDetector faceDetector = new FaceDetector(true, false);

	features = faceDetector.DetectInImage(tempTexture);
	Debug.Log("features = " + features + " features length= " + features.Length);


}

void OnMediaCancelled(object sender, EventArgs e) {
	Log("Image pick cancelled.");
}

public void ShowPictures()
{
	GUIXT.ShowImagePicker();
}

}

Hi, sorry for the late reply. We have just released version 1.7.1.0 with face detection examples. The problem in your code is that the image returned by native iOS is rotated. So you will need to pass the orientation to the face detector. Please see Assets/U3DXT/Examples/coreimage/Anonymous for an example.