EasyAR 3.1.0 - webcam black screen after updating to Unity 2021.1.18f1

EasyAR 3.1.0 worked properly in older versions of Unity. The webcam loaded as expected, but since I've updated to Unity 2021.1.18f1, the webcam only shows a black screen. I tested it with the samples provided here: https://www.easyar.com/view/downloadHistory.html with the same result: the webcam texture stays black. To make sure, that it's not a problem with my webcam, I tried this example here: https://community.theta360.guide/t/simplest-webcam-test-in-unity/516/3 and was able to load the webcam texture properly.

I also tried using another webcam with EasyAR, but the EasyAR webcam texture stays black.

I have no idea what the problem is, since it worked before without any problems. Has anything changed between Unity 2020.2 and 2021.1 in terms of loading the webcam?

Here is the CameraImageRenderer.cs script:

 //================================================================================================================================
 //
 //  Copyright (c) 2015-2019 VisionStar Information Technology (Shanghai) Co., Ltd. All Rights Reserved.
 //  EasyAR is the registered trademark or trademark of VisionStar Information Technology (Shanghai) Co., Ltd in China
 //  and other countries for the augmented reality technology developed by VisionStar Information Technology (Shanghai) Co., Ltd.
 //
 //================================================================================================================================
 
 using System;
 using UnityEngine;
 using UnityEngine.Rendering;
 
 namespace easyar
 {
     [RequireComponent(typeof(RenderCameraController))]
     public class CameraImageRenderer : MonoBehaviour
     {
         private RenderCameraController controller;
         private CommandBuffer commandBuffer;
         private CameraImageMaterial arMaterial;
         private Material material;
         private CameraParameters cameraParameters;
         private bool renderImageHFlip;
         private UserRequest request;
 
         public event Action<Material, Vector2> OnFrameRenderUpdate;
         private event Action<Camera, RenderTexture> TargetTextureChange;
 
         protected virtual void Awake()
         {
             controller = GetComponent<RenderCameraController>();
             arMaterial = new CameraImageMaterial();
         }
 
         protected virtual void OnEnable()
         {
             UpdateCommandBuffer(controller ? controller.TargetCamera : null, material);
         }
 
         protected virtual void OnDisable()
         {
             RemoveCommandBuffer(controller ? controller.TargetCamera : null);
         }
 
         protected virtual void OnDestroy()
         {
             arMaterial.Dispose();
             if (request != null) { request.Dispose(); }
             if (cameraParameters != null) { cameraParameters.Dispose(); }
         }
 
         public void RequestTargetTexture(Action<Camera, RenderTexture> targetTextureEventHandler)
         {
             if (request == null)
             {
                 request = new UserRequest();
             }
             TargetTextureChange += targetTextureEventHandler;
             RenderTexture texture;
             request.UpdateTexture(controller ? controller.TargetCamera : null, material, out texture);
             if (TargetTextureChange != null && texture)
             {
                 TargetTextureChange(controller.TargetCamera, texture);
             }
         }
 
         public void DropTargetTexture(Action<Camera, RenderTexture> targetTextureEventHandler)
         {
             if (controller)
             {
                 targetTextureEventHandler(controller.TargetCamera, null);
             }
             TargetTextureChange -= targetTextureEventHandler;
             if (TargetTextureChange == null && request != null)
             {
                 request.RemoveCommandBuffer(controller ? controller.TargetCamera : null);
                 request.Dispose();
                 request = null;
             }
         }
 
         public void OnAssemble(ARSession session)
         {
             session.FrameChange += OnFrameChange;
             session.FrameUpdate += OnFrameUpdate;
         }
 
         public void SetHFilp(bool hFlip)
         {
             renderImageHFlip = hFlip;
         }
 
         private void OnFrameChange(OutputFrame outputFrame, Matrix4x4 displayCompensation)
         {
             if (outputFrame == null)
             {
                 material = null;
                 UpdateCommandBuffer(controller ? controller.TargetCamera : null, material);
                 if (request != null)
                 {
                     request.UpdateCommandBuffer(controller ? controller.TargetCamera : null, material);
                     RenderTexture texture;
                     if (TargetTextureChange != null && request.UpdateTexture(controller.TargetCamera, material, out texture))
                     {
                         TargetTextureChange(controller.TargetCamera, texture);
                     }
                 }
                 return;
             }
             if (!enabled && request == null && OnFrameRenderUpdate == null)
             {
                 return;
             }
             using (var frame = outputFrame.inputFrame())
             {
                 using (var image = frame.image())
                 {
                     var materialUpdated = arMaterial.UpdateByImage(image);
                     if (material != materialUpdated)
                     {
                         material = materialUpdated;
                         UpdateCommandBuffer(controller ? controller.TargetCamera : null, material);
                         if (request != null) { request.UpdateCommandBuffer(controller ? controller.TargetCamera : null, material); }
                     }
                 }
                 if (cameraParameters != null)
                 {
                     cameraParameters.Dispose();
                 }
                 cameraParameters = frame.cameraParameters();
             }
         }
 
         private void OnFrameUpdate(OutputFrame outputFrame)
         {
             if (!controller || (!enabled && request == null && OnFrameRenderUpdate == null))
             {
                 return;
             }
 
             if (request != null)
             {
                 RenderTexture texture;
                 if (TargetTextureChange != null && request.UpdateTexture(controller.TargetCamera, material, out texture))
                 {
                     TargetTextureChange(controller.TargetCamera, texture);
                 }
             }
 
             if (!material)
             {
                 return;
             }
 
             bool cameraFront = cameraParameters.cameraDeviceType() == CameraDeviceType.Front ? true : false;
             var imageProjection = cameraParameters.imageProjection(controller.TargetCamera.aspect, EasyARController.Instance.Display.Rotation, false, cameraFront? !renderImageHFlip : renderImageHFlip).ToUnityMatrix();
             if (renderImageHFlip)
             {
                 var translateMatrix = Matrix4x4.identity;
                 translateMatrix.m00 = -1;
                 imageProjection = translateMatrix * imageProjection;
             }
             material.SetMatrix("_TextureRotation", imageProjection);
             if (OnFrameRenderUpdate != null)
             {
                 OnFrameRenderUpdate(material, new Vector2(Screen.width * controller.TargetCamera.rect.width, Screen.height * controller.TargetCamera.rect.height));
             }
         }
 
         private void UpdateCommandBuffer(Camera cam, Material material)
         {
             RemoveCommandBuffer(cam);
             if (!cam || !material)
             {
                 return;
             }
             if (enabled)
             {
                 commandBuffer = new CommandBuffer();
                 commandBuffer.Blit(null, BuiltinRenderTextureType.CameraTarget, material);
                 cam.AddCommandBuffer(CameraEvent.BeforeForwardOpaque, commandBuffer);
             }
         }
 
         private void RemoveCommandBuffer(Camera cam)
         {
             if (commandBuffer != null)
             {
                 if (cam)
                 {
                     cam.RemoveCommandBuffer(CameraEvent.BeforeForwardOpaque, commandBuffer);
                 }
                 commandBuffer.Dispose();
                 commandBuffer = null;
             }
         }
 
         private class UserRequest : IDisposable
         {
             private RenderTexture texture;
             private CommandBuffer commandBuffer;
 
             ~UserRequest()
             {
                 if (commandBuffer != null) { commandBuffer.Dispose(); }
                 if (texture) { Destroy(texture); }
             }
 
             public void Dispose()
             {
                 if (commandBuffer != null) { commandBuffer.Dispose(); }
                 if (texture) { Destroy(texture); }
                 GC.SuppressFinalize(this);
             }
 
             public bool UpdateTexture(Camera cam, Material material, out RenderTexture tex)
             {
                 tex = texture;
                 if (!cam || !material)
                 {
                     if (texture)
                     {
                         Destroy(texture);
                         tex = texture = null;
                         return true;
                     }
                     return false;
                 }
                 int w = (int)(Screen.width * cam.rect.width);
                 int h = (int)(Screen.height * cam.rect.height);
                 if (texture && (texture.width != w || texture.height != h))
                 {
                     Destroy(texture);
                 }
 
                 if (texture)
                 {
                     return false;
                 }
                 else
                 {
                     texture = new RenderTexture(w, h, 0);
                     UpdateCommandBuffer(cam, material);
                     tex = texture;
                     return true;
                 }
             }
 
             public void UpdateCommandBuffer(Camera cam, Material material)
             {
                 RemoveCommandBuffer(cam);
                 if (!cam || !material)
                 {
                     return;
                 }
                 if (texture)
                 {
                     commandBuffer = new CommandBuffer();
                     commandBuffer.Blit(null, texture, material);
                     cam.AddCommandBuffer(CameraEvent.BeforeForwardOpaque, commandBuffer);
                 }
             }
 
             public void RemoveCommandBuffer(Camera cam)
             {
                 if (commandBuffer != null)
                 {
                     if (cam)
                     {
                         cam.RemoveCommandBuffer(CameraEvent.BeforeForwardOpaque, commandBuffer);
                     }
                     commandBuffer.Dispose();
                     commandBuffer = null;
                 }
             }
         }
     }
 }
 

Here is the VideoCameraDevice.cs script:

 //================================================================================================================================
 //
 //  Copyright (c) 2015-2019 VisionStar Information Technology (Shanghai) Co., Ltd. All Rights Reserved.
 //  EasyAR is the registered trademark or trademark of VisionStar Information Technology (Shanghai) Co., Ltd in China
 //  and other countries for the augmented reality technology developed by VisionStar Information Technology (Shanghai) Co., Ltd.
 //
 //================================================================================================================================
 
 using System;
 using UnityEngine;
 
 namespace easyar
 {
     public class VideoCameraDevice : CameraSource
     {
         /// <summary>
         /// EasyAR Sense API. Accessible between DeviceCreated and DeviceClosed event if available.
         /// </summary>
         public CameraDevice Device { get; private set; }
 
         public CameraDeviceFocusMode FocusMode = CameraDeviceFocusMode.Continousauto;
         public Vector2 CameraSize = new Vector2(1280, 960);
         public CameraDeviceOpenMethod CameraOpenMethod = CameraDeviceOpenMethod.DeviceType;
         [HideInInspector, SerializeField]
         public CameraDeviceType CameraType = CameraDeviceType.Back;
         [HideInInspector, SerializeField]
         public int CameraIndex = 0;
 
         [HideInInspector, SerializeField]
         private CameraDevicePreference cameraPreference = CameraDevicePreference.PreferObjectSensing;
         private CameraParameters parameters = null;
         private bool willOpen;
 
         public event Action DeviceCreated;
         public event Action DeviceOpened;
         public event Action DeviceClosed;
 
         public enum CameraDeviceOpenMethod
         {
             DeviceType,
             DeviceIndex,
         }
 
         public override int BufferCapacity
         {
             get
             {
                 if (Device != null)
                 {
                     return Device.bufferCapacity();
                 }
                 return bufferCapacity;
             }
             set
             {
                 bufferCapacity = value;
                 if (Device != null)
                 {
                     Device.setBufferCapacity(value);
                 }
             }
         }
 
         public override bool HasSpatialInformation
         {
             get { return false; }
         }
 
         public CameraDevicePreference CameraPreference
         {
             get { return cameraPreference; }
 
             // Switch to prefered FocusMode when switch CameraPreference.
             // You can set other FocusMode after this, but the tracking results may differ.
             set
             {
                 cameraPreference = value;
                 switch (cameraPreference)
                 {
                     case CameraDevicePreference.PreferObjectSensing:
                         FocusMode = CameraDeviceFocusMode.Continousauto;
                         break;
                     case CameraDevicePreference.PreferSurfaceTracking:
                         FocusMode = CameraDeviceFocusMode.Medium;
                         break;
                     default:
                         break;
                 }
             }
         }
 
         public CameraParameters Parameters
         {
             get
             {
                 if (Device != null)
                 {
                     return Device.cameraParameters();
                 }
                 return parameters;
             }
             set
             {
                 parameters = value;
             }
         }
 
         protected override void OnEnable()
         {
             base.OnEnable();
             if (Device != null)
             {
                 Device.start();
             }
         }
 
         protected override void Start()
         {
             if (!CameraDevice.isAvailable())
             {
                 throw new UIPopupException(typeof(CameraDevice) + " not available");
             }
 
             base.Start();
         }
 
         protected override void OnDisable()
         {
             base.OnDisable();
             if (Device != null)
             {
                 Device.stop();
             }
         }
 
         public override void Open()
         {
             willOpen = true;
             CameraDevice.requestPermissions(EasyARController.Scheduler, (Action<PermissionStatus, string>)((status, msg) =>
             {
                 if (!willOpen)
                 {
                     return;
                 }
                 if (status != PermissionStatus.Granted)
                 {
                     throw new UIPopupException("Camera permission not granted");
                 }
 
                 Close();
                 Device = CameraDeviceSelector.createCameraDevice(CameraPreference);
                 if (DeviceCreated != null)
                 {
                     DeviceCreated();
                 }
 
                 bool openResult = false;
                 switch (CameraOpenMethod)
                 {
                     case CameraDeviceOpenMethod.DeviceType:
                         openResult = Device.openWithPreferredType(CameraType);
                         break;
                     case CameraDeviceOpenMethod.DeviceIndex:
                         openResult = Device.openWithIndex(CameraIndex);
                         break;
                     default:
                         break;
                 }
                 if (!openResult)
                 {
                     Debug.LogError("Camera open failed");
                     Device.Dispose();
                     Device = null;
                     return;
                 }
 
                 Device.setFocusMode(FocusMode);
                 Device.setSize(new Vec2I((int)CameraSize.x, (int)CameraSize.y));
                 if (parameters != null)
                 {
                     Device.setCameraParameters(parameters);
                 }
                 if (bufferCapacity != 0)
                 {
                     Device.setBufferCapacity(bufferCapacity);
                 }
 
                 if (sink != null)
                     Device.inputFrameSource().connect(sink);
 
                 if (DeviceOpened != null)
                 {
                     DeviceOpened();
                 }
 
                 if (enabled)
                 {
                     OnEnable();
                 }
             }));
         }
 
         public override void Close()
         {
             willOpen = false;
             if (Device != null)
             {
                 OnDisable();
                 Device.close();
                 Device.Dispose();
                 if (DeviceClosed != null)
                 {
                     DeviceClosed();
                 }
                 Device = null;
             }
         }
 
         public override void Connect(InputFrameSink val)
         {
             base.Connect(val);
             if (Device != null)
             {
                 Device.inputFrameSource().connect(val);
             }
         }
     }
 }
 

Here is the RenderCameraController.cs script:

 //================================================================================================================================
 //
 //  Copyright (c) 2015-2019 VisionStar Information Technology (Shanghai) Co., Ltd. All Rights Reserved.
 //  EasyAR is the registered trademark or trademark of VisionStar Information Technology (Shanghai) Co., Ltd in China
 //  and other countries for the augmented reality technology developed by VisionStar Information Technology (Shanghai) Co., Ltd.
 //
 //================================================================================================================================
 
 using UnityEngine;
 
 namespace easyar
 {
     public class RenderCameraController : MonoBehaviour
     {
         public Camera TargetCamera;
         public RenderCameraParameters ExternalParameters;
 
         private CameraImageRenderer cameraRenderer;
         private Matrix4x4 currentDisplayCompensation = Matrix4x4.identity;
         private CameraParameters cameraParameters;
         private bool projectHFilp;
         private ARSession arSession;
 
         protected virtual void OnEnable()
         {
             if (arSession)
             {
                 arSession.FrameChange += OnFrameChange;
                 arSession.FrameUpdate += OnFrameUpdate;
             }
         }
 
         protected virtual void OnDisable()
         {
             if (arSession)
             {
                 arSession.FrameChange -= OnFrameChange;
                 arSession.FrameUpdate -= OnFrameUpdate;
             }
         }
 
         protected virtual void OnDestroy()
         {
             if (cameraParameters != null)
             {
                 cameraParameters.Dispose();
             }
             if (ExternalParameters)
             {
                 ExternalParameters.Dispose();
             }
         }
 
         internal void OnAssemble(ARSession session)
         {
             arSession = session;
             if (!TargetCamera)
             {
                 TargetCamera = session.Assembly.Camera;
             }
             if (enabled)
             {
                 arSession.FrameChange += OnFrameChange;
                 arSession.FrameUpdate += OnFrameUpdate;
             }
             cameraRenderer = GetComponent<CameraImageRenderer>();
             if (cameraRenderer)
             {
                 cameraRenderer.OnAssemble(session);
             }
         }
 
         internal void SetProjectHFlip(bool hFlip)
         {
             projectHFilp = hFlip;
         }
 
         internal void SetRenderImageHFilp(bool hFlip)
         {
             if (cameraRenderer)
             {
                 cameraRenderer.SetHFilp(hFlip);
             }
         }
 
         private void OnFrameChange(OutputFrame outputFrame, Matrix4x4 displayCompensation)
         {
             if (outputFrame == null)
             {
                 return;
             }
             currentDisplayCompensation = displayCompensation.inverse;
 
             using (var frame = outputFrame.inputFrame())
             {
                 if (cameraParameters != null)
                 {
                     cameraParameters.Dispose();
                 }
                 cameraParameters = frame.cameraParameters();
                 if (ExternalParameters)
                 {
                     ExternalParameters.Build(cameraParameters);
                 }
             }
         }
 
         private void OnFrameUpdate(OutputFrame outputFrame)
         {
             var camParameters = ExternalParameters ? ExternalParameters.Parameters : cameraParameters;
             var projection = camParameters.projection(TargetCamera.nearClipPlane, TargetCamera.farClipPlane, TargetCamera.aspect, EasyARController.Instance.Display.Rotation, false, false).ToUnityMatrix();
             if (ExternalParameters)
             {
                 projection *= ExternalParameters.Transform;
             }
             projection *= currentDisplayCompensation;
             if (projectHFilp)
             {
                 var translateMatrix = Matrix4x4.identity;
                 translateMatrix.m00 = -1;
                 projection = translateMatrix * projection;
             }
             TargetCamera.projectionMatrix = projection;
             GL.invertCulling = projectHFilp;
         }
     }
 }

I am grateful for any tip or help, because I am already getting really desperate how to solve the problem.