HoloLens2で円検出

Question

前提・実現したいこと

HoloLens2でOpenCV for Unityを使い、円検出をしたいと考えています。HoloLensWithOpenCVForUnityExampleにあるcomicfilterexampleの一部を変更して試みましたが円が描画されません。

発生している問題・エラーメッセージ

HoloLens2のgrayscale映像に円が描画されない。

該当のソースコード

using System;
using System.Collections.Generic;
using UnityEngine;
using UnityEngine.UI;
using UnityEngine.SceneManagement;
using OpenCVForUnity.CoreModule;
using OpenCVForUnity.ImgprocModule;
using OpenCVForUnity.UnityUtils.Helper;
using OpenCVForUnity.UnityUtils;
using HoloLensWithOpenCVForUnity.UnityUtils.Helper;
using HoloLensCameraStream;

namespace HoloLensWithOpenCVForUnityExample
{
    /// <summary>
    /// HoloLens Comic Filter Example
    /// An example of image processing (comic filter) using OpenCVForUnity on Hololens.
    /// Referring to http://dev.classmethod.jp/smartphone/opencv-manga-2/.
    /// </summary>
    [RequireComponent(typeof(HololensCameraStreamToMatHelper))]
    public class HoloLensComicFilterExample : MonoBehaviour
    {

        /// <summary>
        /// The texture.
        /// </summary>
        Texture2D texture;

        /// <summary>
        /// The quad renderer.
        /// </summary>
        Renderer quad_renderer;

        /// <summary>
        /// The web cam texture to mat helper.
        /// </summary>
        HololensCameraStreamToMatHelper webCamTextureToMatHelper;

        public float vignetteScale = 1.5f;
        public Slider VignetteScaleSlider;

        readonly static Queue<Action> ExecuteOnMainThread = new Queue<Action>();


        [HeaderAttribute("Debug")]

        public Text renderFPS;
        public Text videoFPS;
        public Text trackFPS;
        public Text debugStr;


        // Use this for initialization
        protected void Start()
        {
            VignetteScaleSlider.value = vignetteScale;

            webCamTextureToMatHelper = gameObject.GetComponent<HololensCameraStreamToMatHelper>();
#if WINDOWS_UWP && !DISABLE_HOLOLENSCAMSTREAM_API
            webCamTextureToMatHelper.frameMatAcquired += OnFrameMatAcquired;
#endif
            webCamTextureToMatHelper.outputColorFormat = WebCamTextureToMatHelper.ColorFormat.GRAY;
            webCamTextureToMatHelper.Initialize();
        }

        /// <summary>
        /// Raises the web cam texture to mat helper initialized event.
        /// </summary>
        public void OnWebCamTextureToMatHelperInitialized()
        {
            Debug.Log("OnWebCamTextureToMatHelperInitialized");

            Mat grayMat = webCamTextureToMatHelper.GetMat();

            texture = new Texture2D(grayMat.cols(), grayMat.rows(), TextureFormat.Alpha8, false);
            texture.wrapMode = TextureWrapMode.Clamp;
            quad_renderer = gameObject.GetComponent<Renderer>() as Renderer;
            quad_renderer.sharedMaterial.SetTexture("_MainTex", texture);


            //Debug.Log("Screen.width " + Screen.width + " Screen.height " + Screen.height + " Screen.orientation " + Screen.orientation);


            DebugUtils.AddDebugStr(webCamTextureToMatHelper.GetWidth() + " x " + webCamTextureToMatHelper.GetHeight() + " : " + webCamTextureToMatHelper.GetFPS());


            Matrix4x4 projectionMatrix;
#if WINDOWS_UWP && !DISABLE_HOLOLENSCAMSTREAM_API
            projectionMatrix = webCamTextureToMatHelper.GetProjectionMatrix ();
            quad_renderer.sharedMaterial.SetMatrix ("_CameraProjectionMatrix", projectionMatrix);
#else
            // This value is obtained from PhotoCapture's TryGetProjectionMatrix() method. I do not know whether this method is good.
            // Please see the discussion of this thread. Https://forums.hololens.com/discussion/782/live-stream-of-locatable-camera-webcam-in-unity
            projectionMatrix = Matrix4x4.identity;
            projectionMatrix.m00 = 2.31029f;
            projectionMatrix.m01 = 0.00000f;
            projectionMatrix.m02 = 0.09614f;
            projectionMatrix.m03 = 0.00000f;
            projectionMatrix.m10 = 0.00000f;
            projectionMatrix.m11 = 4.10427f;
            projectionMatrix.m12 = -0.06231f;
            projectionMatrix.m13 = 0.00000f;
            projectionMatrix.m20 = 0.00000f;
            projectionMatrix.m21 = 0.00000f;
            projectionMatrix.m22 = -1.00000f;
            projectionMatrix.m23 = 0.00000f;
            projectionMatrix.m30 = 0.00000f;
            projectionMatrix.m31 = 0.00000f;
            projectionMatrix.m32 = -1.00000f;
            projectionMatrix.m33 = 0.00000f;
            quad_renderer.sharedMaterial.SetMatrix("_CameraProjectionMatrix", projectionMatrix);
#endif

            quad_renderer.sharedMaterial.SetFloat("_VignetteScale", vignetteScale);


            float halfOfVerticalFov = Mathf.Atan(1.0f / projectionMatrix.m11);
            float aspectRatio = (1.0f / Mathf.Tan(halfOfVerticalFov)) / projectionMatrix.m00;
            Debug.Log("halfOfVerticalFov " + halfOfVerticalFov);
            Debug.Log("aspectRatio " + aspectRatio);

           
        }

        /// <summary>
        /// Raises the web cam texture to mat helper disposed event.
        /// </summary>
        public void OnWebCamTextureToMatHelperDisposed()
        {
            Debug.Log("OnWebCamTextureToMatHelperDisposed");

            lock (ExecuteOnMainThread)
            {
                ExecuteOnMainThread.Clear();
            }

           

            if (debugStr != null)
            {
                debugStr.text = string.Empty;
            }
            DebugUtils.ClearDebugStr();
        }

      

#if WINDOWS_UWP && !DISABLE_HOLOLENSCAMSTREAM_API
        public void OnFrameMatAcquired(Mat grayMat, Matrix4x4 projectionMatrix, Matrix4x4 cameraToWorldMatrix, CameraIntrinsics cameraIntrinsics)
        {
            DebugUtils.VideoTick();

            

            //Imgproc.putText(grayMat, "W:" + grayMat.width() + " H:" + grayMat.height() + " SO:" + Screen.orientation, new Point(5, grayMat.rows() - 10), Imgproc.FONT_HERSHEY_SIMPLEX, 1.0, new Scalar(255), 2, Imgproc.LINE_AA, false);

            DebugUtils.TrackTick();

            Enqueue(() =>
            {

                if (!webCamTextureToMatHelper.IsPlaying()) return;

                Utils.fastMatToTexture2D(grayMat, texture);
                grayMat.Dispose();

                Matrix4x4 worldToCameraMatrix = cameraToWorldMatrix.inverse;

                quad_renderer.sharedMaterial.SetMatrix("_WorldToCameraMatrix", worldToCameraMatrix);

                // Position the canvas object slightly in front
                // of the real world web camera.
                Vector3 position = cameraToWorldMatrix.GetColumn(3) - cameraToWorldMatrix.GetColumn(2) * 2.2f;

                // Rotate the canvas object so that it faces the user.
                Quaternion rotation = Quaternion.LookRotation(-cameraToWorldMatrix.GetColumn(2), cameraToWorldMatrix.GetColumn(1));

                gameObject.transform.position = position;
                gameObject.transform.rotation = rotation;

            });
        }

        private void Update()
        {
            lock (ExecuteOnMainThread)
            {
                while (ExecuteOnMainThread.Count > 0)
                {
                    ExecuteOnMainThread.Dequeue().Invoke();
                }
            }
        }

        private void Enqueue(Action action)
        {
            lock (ExecuteOnMainThread)
            {
                ExecuteOnMainThread.Enqueue(action);
            }
        }

#else
        // Update is called once per frame
　　　　//円検出
        void Update()
        {
            if (webCamTextureToMatHelper.IsPlaying() && webCamTextureToMatHelper.DidUpdateThisFrame())
            {
                DebugUtils.VideoTick();

                Mat grayMat = webCamTextureToMatHelper.GetMat();

                using (Mat circles = new Mat())
                {

                    Imgproc.HoughCircles(grayMat, circles, Imgproc.CV_HOUGH_GRADIENT, 2, 10, 160, 50, 10, 40);
                    Point pt = new Point();

                    for (int i = 0; i < circles.cols(); i++)
                    {
                        double[] data = circles.get(0, i);
                        pt.x = data[0];
                        pt.y = data[1];
                        double rho = data[2];

                        Imgproc.circle(grayMat, pt, (int)rho, new Scalar(255, 0, 0, 255), 5);
                    }
                }

                //Imgproc.putText(grayMat, "W:" + grayMat.width() + " H:" + grayMat.height() + " SO:" + Screen.orientation, new Point(5, grayMat.rows() - 10), Imgproc.FONT_HERSHEY_SIMPLEX, 1.0, new Scalar(255), 2, Imgproc.LINE_AA, false);

                DebugUtils.TrackTick();

                Utils.fastMatToTexture2D(grayMat, texture);
            }

        }
#endif