feat: add FaceDetector sample (#975)

* chore: remove unused directories

* refactor: dispose Timestamp

* feat: FaceDetector Sample

* feat: transform the input image properly

* test: add ImageTransformationOptions tests

* chore: rename elements in prefab

* feat: switch delegate at runtime

* refactor: make VisionTaskApiRunner generic

* refactor: rename FaceDetectorSample to FaceDetectorRunner

* ci: set timeout for the license activation step

.github/workflows/windows-test.yml

@@ -109,6 +109,7 @@ jobs:
           {
             exit $process.ExitCode
           }
+        timeout-minutes: 1
 
       - name: Download built artifacts
         uses: actions/download-artifact@v3

Assets/MediaPipeUnity/Samples/Common/Scripts/EnumExtension.cs

@@ -0,0 +1,37 @@
+// Copyright (c) 2023 homuler
+//
+// Use of this source code is governed by an MIT-style
+// license that can be found in the LICENSE file or at
+// https://opensource.org/licenses/MIT.
+
+using System;
+using System.ComponentModel;
+
+namespace Mediapipe.Unity.Sample
+{
+  public static class EnumExtension
+  {
+    public static string GetDescription(this Enum value)
+    {
+      var type = value.GetType();
+      var name = Enum.GetName(type, value);
+      if (name == null)
+      {
+        return null;
+      }
+
+      var field = type.GetField(name);
+      if (field == null)
+      {
+        return null;
+      }
+
+      var attr = Attribute.GetCustomAttribute(field, typeof(DescriptionAttribute));
+      if (attr is DescriptionAttribute descriptionAttribute)
+      {
+        return descriptionAttribute.Description;
+      }
+      return null;
+    }
+  }
+}

Assets/MediaPipeUnity/Samples/Common/Scripts/ImageTransformationOptions.cs

@@ -0,0 +1,41 @@
+// Copyright (c) 2023 homuler
+//
+// Use of this source code is governed by an MIT-style
+// license that can be found in the LICENSE file or at
+// https://opensource.org/licenses/MIT.
+
+namespace Mediapipe.Unity.Sample
+{
+  public readonly struct ImageTransformationOptions
+  {
+    public readonly bool flipHorizontally;
+    public readonly bool flipVertically;
+    public readonly RotationAngle rotationAngle;
+
+    private ImageTransformationOptions(bool flipHorizontally, bool flipVertically, RotationAngle rotationAngle)
+    {
+      this.flipHorizontally = flipHorizontally;
+      this.flipVertically = flipVertically;
+      this.rotationAngle = rotationAngle;
+    }
+
+    public static ImageTransformationOptions Build(bool shouldFlipHorizontally, bool isVerticallyFlipped, RotationAngle rotation)
+    {
+      var isInverted = CoordinateSystem.ImageCoordinate.IsInverted(rotation);
+      var flipHorizontally = !isInverted && shouldFlipHorizontally;
+      var flipVertically = !shouldFlipHorizontally ? !isVerticallyFlipped : isInverted ? isVerticallyFlipped : !isVerticallyFlipped;
+
+      return new ImageTransformationOptions(flipHorizontally, flipVertically, rotation);
+    }
+  }
+
+  public static class ImageSourceExtension
+  {
+    public static ImageTransformationOptions GetTransformationOptions(this ImageSource imageSource, bool expectedToBeMirrored = false)
+    {
+      var shouldFlipHorizontally = (imageSource.isFrontFacing || expectedToBeMirrored) ^ imageSource.isHorizontallyFlipped;
+      var shouldFlipVertically = imageSource.isVerticallyFlipped;
+      return ImageTransformationOptions.Build(shouldFlipHorizontally, shouldFlipVertically, imageSource.rotation);
+    }
+  } 
+}

Assets/MediaPipeUnity/Samples/Common/Scripts/Screen.cs

@@ -17,7 +17,7 @@ public class Screen : MonoBehaviour
 
     public Texture texture
     {
-      private get => _screen.texture;
+      get => _screen.texture;
       set => _screen.texture = value;
     }
 

Assets/MediaPipeUnity/Samples/Common/Scripts/TaskApiRunner.cs

@@ -0,0 +1,98 @@
+// Copyright (c) 2023 homuler
+//
+// Use of this source code is governed by an MIT-style
+// license that can be found in the LICENSE file or at
+// https://opensource.org/licenses/MIT.
+
+using System;
+using System.Collections;
+using UnityEngine;
+
+using Stopwatch = System.Diagnostics.Stopwatch;
+
+namespace Mediapipe.Unity.Sample
+{
+  public abstract class TaskApiRunner : MonoBehaviour
+  {
+#pragma warning disable IDE1006
+    // TODO: make it static
+    protected virtual string TAG => GetType().Name;
+#pragma warning restore IDE1006
+
+    public Bootstrap bootstrap;
+    protected bool isPaused;
+
+    private readonly Stopwatch _stopwatch = new();
+
+    protected virtual IEnumerator Start()
+    {
+      bootstrap = FindBootstrap();
+      yield return new WaitUntil(() => bootstrap.isFinished);
+
+      Play();
+    }
+
+    /// <summary>
+    ///   Start the main program from the beginning.
+    /// </summary>
+    public virtual void Play()
+    {
+      isPaused = false;
+      _stopwatch.Restart();
+    }
+
+    /// <summary>
+    ///   Pause the main program.
+    /// <summary>
+    public virtual void Pause()
+    {
+      isPaused = true;
+    }
+
+    /// <summary>
+    ///    Resume the main program.
+    ///    If the main program has not begun, it'll do nothing.
+    /// </summary>
+    public virtual void Resume()
+    {
+      isPaused = false;
+    }
+
+    /// <summary>
+    ///   Stops the main program.
+    /// </summary>
+    public virtual void Stop()
+    {
+      isPaused = true;
+      _stopwatch.Stop();
+    }
+
+    protected long GetCurrentTimestampMillisec() => _stopwatch.IsRunning ? _stopwatch.ElapsedTicks / TimeSpan.TicksPerMillisecond : -1;
+
+    protected Bootstrap FindBootstrap()
+    {
+      var bootstrapObj = GameObject.Find("Bootstrap");
+
+      if (bootstrapObj != null)
+      {
+        return bootstrapObj.GetComponent<Bootstrap>();
+      }
+
+      Logger.LogWarning(TAG, "Global Bootstrap instance is not found (maybe running a sample scene directly), "
+                            + "so activating a fallback Bootstrap instance attached to each Solution object");
+
+      var bootstrap = GetComponent<Bootstrap>();
+      bootstrap.enabled = true;
+
+      // hide menu button when trying a single scene.
+      DisableMenuButton();
+      return bootstrap;
+    }
+
+    private void DisableMenuButton()
+    {
+      var menuButton = GameObject.Find("MenuButton");
+      menuButton.SetActive(false);
+    }
+  }
+}

Assets/MediaPipeUnity/Samples/Common/Scripts/VisionTaskApiRunner.cs

@@ -0,0 +1,60 @@
+// Copyright (c) 2021 homuler
+//
+// Use of this source code is governed by an MIT-style
+// license that can be found in the LICENSE file or at
+// https://opensource.org/licenses/MIT.
+
+using System.Collections;
+using UnityEngine;
+
+namespace Mediapipe.Unity.Sample
+{
+  public abstract class VisionTaskApiRunner<TTask> : TaskApiRunner where TTask : Tasks.Vision.Core.BaseVisionTaskApi
+  {
+    [SerializeField] protected Screen screen;
+
+    private Coroutine _coroutine;
+    protected TTask taskApi;
+
+    public RunningMode runningMode;
+
+    public override void Play()
+    {
+      if (_coroutine != null)
+      {
+        Stop();
+      }
+      base.Play();
+      _coroutine = StartCoroutine(Run());
+    }
+
+    public override void Pause()
+    {
+      base.Pause();
+      ImageSourceProvider.ImageSource.Pause();
+    }
+
+    public override void Resume()
+    {
+      base.Resume();
+      var _ = StartCoroutine(ImageSourceProvider.ImageSource.Resume());
+    }
+
+    public override void Stop()
+    {
+      base.Stop();
+      StopCoroutine(_coroutine);
+      ImageSourceProvider.ImageSource.Stop();
+      taskApi?.Close();
+      taskApi = null;
+    }
+
+    protected abstract IEnumerator Run();
+
+    protected static void SetupAnnotationController<T>(AnnotationController<T> annotationController, ImageSource imageSource, bool expectedToBeMirrored = false) where T : HierarchicalAnnotation
+    {
+      annotationController.isMirrored = expectedToBeMirrored;
+      annotationController.imageSize = new Vector2Int(imageSource.textureWidth, imageSource.textureHeight);
+    }
+  }
+}

Assets/MediaPipeUnity/Samples/Mediapipe.Unity.Sample.asmdef

@@ -0,0 +1,16 @@
+{
+    "name": "Mediapipe.Unity.Sample",
+    "rootNamespace": "",
+    "references": [
+        "GUID:04c4d86a70aa56c55a78c61f1ab1a56d"
+    ],
+    "includePlatforms": [],
+    "excludePlatforms": [],
+    "allowUnsafeCode": false,
+    "overrideReferences": false,
+    "precompiledReferences": [],
+    "autoReferenced": true,
+    "defineConstraints": [],
+    "versionDefines": [],
+    "noEngineReferences": false
+}