diff --git a/AssetStudio/Classes/VideoClip.cs b/AssetStudio/Classes/VideoClip.cs
index 504ff47..dbefcd2 100644
--- a/AssetStudio/Classes/VideoClip.cs
+++ b/AssetStudio/Classes/VideoClip.cs
@@ -20,7 +20,7 @@ namespace AssetStudio
             var m_ProxyHeight = reader.ReadUInt32();
             var Width = reader.ReadUInt32();
             var Height = reader.ReadUInt32();
-            if (version[0] >= 2017) //2017.x and up
+            if (version[0] > 2017 || (version[0] == 2017 && version[1] >= 2)) //2017.2 and up
             {
                 var m_PixelAspecRatioNum = reader.ReadUInt32();
                 var m_PixelAspecRatioDen = reader.ReadUInt32();
diff --git a/AssetStudio/Math/Matrix4x4f.cs b/AssetStudio/Math/Matrix4x4f.cs
index 40c2e35..429afc7 100644
--- a/AssetStudio/Math/Matrix4x4f.cs
+++ b/AssetStudio/Math/Matrix4x4f.cs
@@ -83,7 +83,7 @@ namespace AssetStudio
                     case 13: return M13;
                     case 14: return M23;
                     case 15: return M33;
-                    default: throw new IndexOutOfRangeException("Invalid matrix index!");
+                    default: throw new ArgumentOutOfRangeException(nameof(index), "Invalid Matrix4x4 index!");
                 }
             }
 
@@ -107,7 +107,7 @@ namespace AssetStudio
                     case 13: M13 = value; break;
                     case 14: M23 = value; break;
                     case 15: M33 = value; break;
-                    default: throw new IndexOutOfRangeException("Invalid matrix index!");
+                    default: throw new ArgumentOutOfRangeException(nameof(index), "Invalid Matrix4x4 index!");
                 }
             }
         }
diff --git a/AssetStudio/Math/Quaternion.cs b/AssetStudio/Math/Quaternion.cs
index 063d1f2..ca129f5 100644
--- a/AssetStudio/Math/Quaternion.cs
+++ b/AssetStudio/Math/Quaternion.cs
@@ -29,7 +29,7 @@ namespace AssetStudio
                     case 1: return Y;
                     case 2: return Z;
                     case 3: return W;
-                    default: throw new IndexOutOfRangeException("Invalid Quaternion index!");
+                    default: throw new ArgumentOutOfRangeException(nameof(index), "Invalid Quaternion index!");
                 }
             }
 
@@ -41,7 +41,7 @@ namespace AssetStudio
                     case 1: Y = value; break;
                     case 2: Z = value; break;
                     case 3: W = value; break;
-                    default: throw new IndexOutOfRangeException("Invalid Quaternion index!");
+                    default: throw new ArgumentOutOfRangeException(nameof(index), "Invalid Quaternion index!");
                 }
             }
         }
@@ -62,5 +62,27 @@ namespace AssetStudio
         {
             return X.Equals(other.X) && Y.Equals(other.Y) && Z.Equals(other.Z) && W.Equals(other.W);
         }
+
+        public static float Dot(Quaternion a, Quaternion b)
+        {
+            return a.X * b.X + a.Y * b.Y + a.Z * b.Z + a.W * b.W;
+        }
+
+        private static bool IsEqualUsingDot(float dot)
+        {
+            return dot > 1.0f - kEpsilon;
+        }
+
+        public static bool operator ==(Quaternion lhs, Quaternion rhs)
+        {
+            return IsEqualUsingDot(Dot(lhs, rhs));
+        }
+
+        public static bool operator !=(Quaternion lhs, Quaternion rhs)
+        {
+            return !(lhs == rhs);
+        }
+
+        private const float kEpsilon = 0.000001F;
     }
 }
diff --git a/AssetStudio/Math/Vector2.cs b/AssetStudio/Math/Vector2.cs
index 18e9268..bfcfa0d 100644
--- a/AssetStudio/Math/Vector2.cs
+++ b/AssetStudio/Math/Vector2.cs
@@ -23,8 +23,7 @@ namespace AssetStudio
                 {
                     case 0: return X;
                     case 1: return Y;
-                    default:
-                        throw new IndexOutOfRangeException("Invalid Vector2 index!");
+                    default: throw new ArgumentOutOfRangeException(nameof(index), "Invalid Vector2 index!");
                 }
             }
 
@@ -34,8 +33,7 @@ namespace AssetStudio
                 {
                     case 0: X = value; break;
                     case 1: Y = value; break;
-                    default:
-                        throw new IndexOutOfRangeException("Invalid Vector2 index!");
+                    default: throw new ArgumentOutOfRangeException(nameof(index), "Invalid Vector2 index!");
                 }
             }
         }
diff --git a/AssetStudio/Math/Vector3.cs b/AssetStudio/Math/Vector3.cs
index 9bd5c4b..31402e4 100644
--- a/AssetStudio/Math/Vector3.cs
+++ b/AssetStudio/Math/Vector3.cs
@@ -26,8 +26,7 @@ namespace AssetStudio
                     case 0: return X;
                     case 1: return Y;
                     case 2: return Z;
-                    default:
-                        throw new IndexOutOfRangeException("Invalid Vector3 index!");
+                    default: throw new ArgumentOutOfRangeException(nameof(index), "Invalid Vector3 index!");
                 }
             }
 
@@ -38,8 +37,7 @@ namespace AssetStudio
                     case 0: X = value; break;
                     case 1: Y = value; break;
                     case 2: Z = value; break;
-                    default:
-                        throw new IndexOutOfRangeException("Invalid Vector3 index!");
+                    default: throw new ArgumentOutOfRangeException(nameof(index), "Invalid Vector3 index!");
                 }
             }
         }
diff --git a/AssetStudio/Math/Vector4.cs b/AssetStudio/Math/Vector4.cs
index ed4dc7a..fdac8fd 100644
--- a/AssetStudio/Math/Vector4.cs
+++ b/AssetStudio/Math/Vector4.cs
@@ -37,7 +37,7 @@ namespace AssetStudio
                     case 1: return Y;
                     case 2: return Z;
                     case 3: return W;
-                    default: throw new IndexOutOfRangeException("Invalid Vector4 index!");
+                    default: throw new ArgumentOutOfRangeException(nameof(index), "Invalid Vector4 index!");
                 }
             }
 
@@ -49,7 +49,7 @@ namespace AssetStudio
                     case 1: Y = value; break;
                     case 2: Z = value; break;
                     case 3: W = value; break;
-                    default: throw new IndexOutOfRangeException("Invalid Vector4 index!");
+                    default: throw new ArgumentOutOfRangeException(nameof(index), "Invalid Vector4 index!");
                 }
             }
         }
diff --git a/AssetStudioUtility/ModelConverter.cs b/AssetStudioUtility/ModelConverter.cs
index 165d1fc..fcc0d1c 100644
--- a/AssetStudioUtility/ModelConverter.cs
+++ b/AssetStudioUtility/ModelConverter.cs
@@ -380,10 +380,11 @@ namespace AssetStudio
                         }
                     }
                 }
-                else if (mesh.m_BindPose.Length > 0 && mesh.m_BoneNameHashes?.Length > 0 && mesh.m_BindPose.Length == mesh.m_BoneNameHashes.Length)
+                else if (mesh.m_BindPose.Length > 0 && mesh.m_BoneNameHashes?.Length > 0)
                 {
-                    iMesh.BoneList = new List<ImportedBone>(mesh.m_BoneNameHashes.Length);
-                    for (int i = 0; i < mesh.m_BoneNameHashes.Length; i++)
+                    var boneMax = Math.Min(mesh.m_BindPose.Length, mesh.m_BoneNameHashes.Length);
+                    iMesh.BoneList = new List<ImportedBone>(boneMax);
+                    for (int i = 0; i < boneMax; i++)
                     {
                         var bone = new ImportedBone();
                         var boneHash = mesh.m_BoneNameHashes[i];