First release of writing out COCO and perception format in parallel

com.unity.perception/Runtime/GroundTruth/SimulationState.cs

 using UnityEngine;
 using UnityEngine.Perception.GroundTruth.Exporters;
 using UnityEngine.Perception.GroundTruth.Exporters.Coco;
+using UnityEngine.Perception.GroundTruth.Exporters.CocoHybrid;
 using UnityEngine.Perception.GroundTruth.Exporters.PerceptionFormat;
 using UnityEngine.Perception.GroundTruth.Exporters.PerceptionNew;
 using UnityEngine.Profiling;
                     _ActiveReporter = new PerceptionExporter();
                     break;
                 case nameof(CocoExporter):
-                    _ActiveReporter = new CocoExporter();
+                    //_ActiveReporter = new CocoExporter();
+                    _ActiveReporter = new CocoHybridExporter();
                     break;
                 case nameof(PerceptionNewExporter):
                     _ActiveReporter = new PerceptionNewExporter();

com.unity.perception/Runtime/GroundTruth/Exporters/CocoHybrid.meta

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com.unity.perception/Runtime/GroundTruth/Exporters/CocoHybrid/CocoHybridExporter.cs

+using System;
+using System.Collections.Generic;
+using System.Threading.Tasks;
+using UnityEngine.Perception.GroundTruth.Exporters.Coco;
+using UnityEngine.Perception.GroundTruth.Exporters.PerceptionFormat;
+
+namespace UnityEngine.Perception.GroundTruth.Exporters.CocoHybrid
+{
+    public class CocoHybridExporter : IDatasetExporter
+    {
+        CocoExporter m_Coco = new CocoExporter();
+        PerceptionExporter m_Perception = new PerceptionExporter();
+
+        public string GetRgbCaptureFilename(params (string, object)[] additionalSensorValues)
+        {
+            return m_Coco.GetRgbCaptureFilename(additionalSensorValues) + m_Perception.GetRgbCaptureFilename(additionalSensorValues);
+        }
+
+        public void OnSimulationBegin(string directoryName)
+        {
+            m_Coco.OnSimulationBegin(directoryName + "_coco");
+            m_Perception.OnSimulationBegin(directoryName);
+        }
+
+        public void OnSimulationEnd()
+        {
+            m_Coco.OnSimulationEnd();
+            m_Perception.OnSimulationEnd();
+        }
+
+        public void OnAnnotationRegistered<TSpec>(Guid annotationId, TSpec[] values)
+        {
+            m_Coco.OnAnnotationRegistered(annotationId, values);
+            m_Perception.OnAnnotationRegistered(annotationId, values);
+        }
+
+        public async Task ProcessPendingCaptures(List<SimulationState.PendingCapture> pendingCaptures, SimulationState simState)
+        {
+            var cocoTask = m_Coco.ProcessPendingCaptures(pendingCaptures, simState);
+            var perceptionTask = m_Perception.ProcessPendingCaptures(pendingCaptures, simState);
+            await cocoTask;
+            await perceptionTask;
+        }
+
+        public async Task OnCaptureReported(int frame, int width, int height, string filename)
+        {
+            var cocoTask = m_Coco.OnCaptureReported(frame, width, height, filename);
+            var perceptionTask = m_Perception.OnCaptureReported(frame, width, height, filename);
+            await cocoTask;
+            await perceptionTask;
+        }
+    }
+}

com.unity.perception/Runtime/GroundTruth/Exporters/CocoHybrid/CocoHybridExporter.cs.meta

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