Implement util method that create tensor from metadata

Author: asus4

Packages/com.github.asus4.onnxruntime.unity/Runtime/ImageInference.cs

@@ -116,7 +116,7 @@ private static (string[], OrtValue[]) AllocateTensors(IReadOnlyDictionary<string
                 if (meta.IsTensor)
                 {
                     names.Add(kv.Key);
-                    values.Add(TensorFromMetadata(meta));
+                    values.Add(meta.CreateTensorOrtValue());
                 }
                 else
                 {
@@ -126,14 +126,6 @@ private static (string[], OrtValue[]) AllocateTensors(IReadOnlyDictionary<string
             return (names.ToArray(), values.ToArray());
         }
 
-        private static OrtValue TensorFromMetadata(NodeMetadata metadata)
-        {
-            long[] shape = metadata.Dimensions.Select(x => (long)x).ToArray();
-            var ortValue = OrtValue.CreateAllocatedTensorValue(
-                OrtAllocator.DefaultInstance, metadata.ElementDataType, shape);
-            return ortValue;
-        }
-
         private static bool IsSupportedImage(int[] shape)
         {
             int channels = shape.Length switch

Packages/com.github.asus4.onnxruntime.unity/Runtime/InferenceSessionExtension.cs

@@ -1,4 +1,6 @@
+using System;
 using System.Diagnostics;
+using System.Linq;
 using System.Text;
 
 namespace Microsoft.ML.OnnxRuntime.Unity
@@ -37,5 +39,22 @@ public static void LogIOInfo(this InferenceSession session)
 
             UnityEngine.Debug.Log(sb.ToString());
         }
+
+        /// <summary>
+        /// Create OrtValue from NodeMetadata
+        /// </summary>
+        /// <param name="metadata">A metadata</param>
+        /// <returns>Allocated OrtValue, should be disposed.</returns>
+        public static OrtValue CreateTensorOrtValue(this NodeMetadata metadata)
+        {
+            if (!metadata.IsTensor)
+            {
+                throw new ArgumentException("metadata must be tensor");
+            }
+            long[] shape = metadata.Dimensions.Select(x => (long)x).ToArray();
+            var ortValue = OrtValue.CreateAllocatedTensorValue(
+                OrtAllocator.DefaultInstance, metadata.ElementDataType, shape);
+            return ortValue;
+        }
     }
 }