diff --git a/avs_core/core/avisynth.cpp b/avs_core/core/avisynth.cpp
index bda6ee602..8749256ca 100644
--- a/avs_core/core/avisynth.cpp
+++ b/avs_core/core/avisynth.cpp
@@ -4442,6 +4442,54 @@ PVideoFrame ScriptEnvironment::NewVideoFrameOnDevice(const VideoInfo& vi, int al
     case VideoInfo::CS_YUVA420PS:
     case VideoInfo::CS_YUVA422PS:
     case VideoInfo::CS_YUVA444PS:
+        // planar 4:4:0
+    case VideoInfo::CS_YUV440:
+    case VideoInfo::CS_YUV440P10:
+    case VideoInfo::CS_YUV440P12:
+    case VideoInfo::CS_YUV440P14:
+    case VideoInfo::CS_YUV440P16:
+    case VideoInfo::CS_YUV440PS:
+        // planar 4:4:0:A
+    case VideoInfo::CS_YUVA440:
+    case VideoInfo::CS_YUVA440P10:
+    case VideoInfo::CS_YUVA440P12:
+    case VideoInfo::CS_YUVA440P14:
+    case VideoInfo::CS_YUVA440P16:
+    case VideoInfo::CS_YUVA440PS:
+        // planar 4:1:1
+    case VideoInfo::CS_YUV411P10:
+    case VideoInfo::CS_YUV411P12:
+    case VideoInfo::CS_YUV411P14:
+    case VideoInfo::CS_YUV411P16:
+    case VideoInfo::CS_YUV411PS:
+        // planar 4:1:1:A
+    case VideoInfo::CS_YUVA411:
+    case VideoInfo::CS_YUVA411P10:
+    case VideoInfo::CS_YUVA411P12:
+    case VideoInfo::CS_YUVA411P14:
+    case VideoInfo::CS_YUVA411P16:
+    case VideoInfo::CS_YUVA411PS:
+        // planar 4:1:0
+    case VideoInfo::CS_YUV410:
+    case VideoInfo::CS_YUV410P10:
+    case VideoInfo::CS_YUV410P12:
+    case VideoInfo::CS_YUV410P14:
+    case VideoInfo::CS_YUV410P16:
+    case VideoInfo::CS_YUV410PS:
+        // planar 4:1:0:A
+    case VideoInfo::CS_YUVA410:
+    case VideoInfo::CS_YUVA410P10:
+    case VideoInfo::CS_YUVA410P12:
+    case VideoInfo::CS_YUVA410P14:
+    case VideoInfo::CS_YUVA410P16:
+    case VideoInfo::CS_YUVA410PS:
+        // Y+α 4:0:0:A
+    case VideoInfo::CS_YA8:
+    case VideoInfo::CS_YA10:
+    case VideoInfo::CS_YA12:
+    case VideoInfo::CS_YA14:
+    case VideoInfo::CS_YA16:
+    case VideoInfo::CS_YA32:
         break;
     default:
       ThrowError("Filter Error: Filter attempted to create VideoFrame with invalid pixel_type.");
diff --git a/avs_core/core/avisynth.def b/avs_core/core/avisynth.def
index 6a81bb6d9..a8865bb94 100644
--- a/avs_core/core/avisynth.def
+++ b/avs_core/core/avisynth.def
@@ -169,3 +169,7 @@ EXPORTS
   avs_release_global_lock = _avs_release_global_lock@8
 
   avs_get_cpu_flags_ex = _avs_get_cpu_flags_ex@4
+  avs_is_440 = _avs_is_440@4
+  avs_is_ya = _avs_is_ya@4
+  avs_is_410 = _avs_is_410@4
+  avs_is_411 = _avs_is_411@4
diff --git a/avs_core/core/avisynth_c.cpp b/avs_core/core/avisynth_c.cpp
index 7f2918261..1c85e76e7 100644
--- a/avs_core/core/avisynth_c.cpp
+++ b/avs_core/core/avisynth_c.cpp
@@ -747,6 +747,34 @@ void AVSC_CC avs_clear_map(AVS_ScriptEnvironment * p, AVS_Map * map)
   }
 }
 
+extern "C"
+int AVSC_CC avs_is_440(const AVS_VideoInfo * p)
+{
+  return ((p->pixel_type & AVS_CS_PLANAR_MASK & ~AVS_CS_SAMPLE_BITS_MASK) == (AVS_CS_GENERIC_YUV440 & AVS_CS_PLANAR_FILTER)) ||
+    ((p->pixel_type & AVS_CS_PLANAR_MASK & ~AVS_CS_SAMPLE_BITS_MASK) == (AVS_CS_GENERIC_YUVA440 & AVS_CS_PLANAR_FILTER));
+}
+
+extern "C"
+int AVSC_CC avs_is_ya(const AVS_VideoInfo * p)
+{
+  return ((p->pixel_type & AVS_CS_PLANAR_MASK & ~AVS_CS_SAMPLE_BITS_MASK) == (AVS_CS_GENERIC_YA & AVS_CS_PLANAR_FILTER)) ||
+    ((p->pixel_type & AVS_CS_PLANAR_MASK & ~AVS_CS_SAMPLE_BITS_MASK) == (AVS_CS_GENERIC_YA & AVS_CS_PLANAR_FILTER));
+}
+
+extern "C"
+int AVSC_CC avs_is_410(const AVS_VideoInfo * p)
+{
+  return ((p->pixel_type & AVS_CS_PLANAR_MASK & ~AVS_CS_SAMPLE_BITS_MASK) == (AVS_CS_GENERIC_YUV410 & AVS_CS_PLANAR_FILTER)) ||
+    ((p->pixel_type & AVS_CS_PLANAR_MASK & ~AVS_CS_SAMPLE_BITS_MASK) == (AVS_CS_GENERIC_YUVA410 & AVS_CS_PLANAR_FILTER));
+}
+
+extern "C"
+int AVSC_CC avs_is_411(const AVS_VideoInfo * p)
+{
+  return ((p->pixel_type & AVS_CS_PLANAR_MASK & ~AVS_CS_SAMPLE_BITS_MASK) == (AVS_CS_GENERIC_YUV411 & AVS_CS_PLANAR_FILTER)) ||
+    ((p->pixel_type & AVS_CS_PLANAR_MASK & ~AVS_CS_SAMPLE_BITS_MASK) == (AVS_CS_GENERIC_YUVA411 & AVS_CS_PLANAR_FILTER));
+}
+
 
 
 /////////////////////////////////////////////////////////////////////
diff --git a/avs_core/core/interface.cpp b/avs_core/core/interface.cpp
index adbf2790f..0762a3d16 100644
--- a/avs_core/core/interface.cpp
+++ b/avs_core/core/interface.cpp
@@ -430,6 +430,14 @@ unsigned int VideoInfo::GetChannelMask() const
   return dwChannelMask >> 4;
 }
 
+bool VideoInfo::Is440()  const { return ((pixel_type & CS_PLANAR_MASK & ~CS_Sample_Bits_Mask) == (CS_GENERIC_YUV440 & CS_PLANAR_FILTER)) ||
+                                        ((pixel_type & CS_PLANAR_MASK & ~CS_Sample_Bits_Mask) == (CS_GENERIC_YUVA440 & CS_PLANAR_FILTER)) ; }
+bool VideoInfo::IsYA()   const { return ((pixel_type & CS_PLANAR_MASK & ~CS_Sample_Bits_Mask) == (CS_GENERIC_YA & CS_PLANAR_FILTER)) ||
+                                        ((pixel_type & CS_PLANAR_MASK & ~CS_Sample_Bits_Mask) == (CS_GENERIC_YA & CS_PLANAR_FILTER)) ; }
+bool VideoInfo::Is410()  const { return ((pixel_type & CS_PLANAR_MASK & ~CS_Sample_Bits_Mask) == (CS_GENERIC_YUV410 & CS_PLANAR_FILTER)) ||
+                                        ((pixel_type & CS_PLANAR_MASK & ~CS_Sample_Bits_Mask) == (CS_GENERIC_YUVA410 & CS_PLANAR_FILTER)) ; }
+bool VideoInfo::Is411()  const { return ((pixel_type & CS_PLANAR_MASK & ~CS_Sample_Bits_Mask) == (CS_GENERIC_YUV411 & CS_PLANAR_FILTER)) ||
+                                        ((pixel_type & CS_PLANAR_MASK & ~CS_Sample_Bits_Mask) == (CS_GENERIC_YUVA411 & CS_PLANAR_FILTER)) ; }
 
 // end struct VideoInfo
 
@@ -1312,6 +1320,12 @@ static const AVS_Linkage avs_linkage = {    // struct AVS_Linkage {
   &VideoInfo::SetChannelMask,               //   void    (VideoInfo::*SetChannelMask)();
   &VideoInfo::GetChannelMask,               //   int     (VideoInfo::*GetChannelMask)()  const;
 
+  // V13
+  &VideoInfo::Is440,                        //   bool    (VideoInfo::*Is440)()  const;
+  &VideoInfo::IsYA,                         //   bool    (VideoInfo::*IsYA)()  const;
+  &VideoInfo::Is410,                        //   bool    (VideoInfo::*Is410)()  const;
+  &VideoInfo::Is411,                        //   bool    (VideoInfo::*Is411)()  const;
+
   // a single { nullptr } initializes the whole placeholder array
   { nullptr },                              // void          (VideoInfo::* reserved2[64 - 31])(); // Reserve pointer space for Avisynth+
 
diff --git a/avs_core/core/parser/script.cpp b/avs_core/core/parser/script.cpp
index 911eaf21f..0fc0f92bc 100644
--- a/avs_core/core/parser/script.cpp
+++ b/avs_core/core/parser/script.cpp
@@ -360,6 +360,12 @@ extern const AVSFunction Script_functions[] = {
   /*
   { "IsArrayOf", BUILTIN_FUNC_PREFIX, ".s", IsArrayOf },
   */
+
+  { "Is440",  BUILTIN_FUNC_PREFIX, "c", Is440 },
+  { "IsYA",   BUILTIN_FUNC_PREFIX, "c", IsYA },
+  { "Is410",  BUILTIN_FUNC_PREFIX, "c", Is410 },
+  { "Is411",  BUILTIN_FUNC_PREFIX, "c", Is411 },
+
   { 0 }
 };
 
@@ -1583,6 +1589,53 @@ static const std::map<int, std::string> pixel_format_table =
   {VideoInfo::CS_RGBAP14   , "RGBAP14"},
   {VideoInfo::CS_RGBAP16   , "RGBAP16"},
   {VideoInfo::CS_RGBAPS    , "RGBAPS"},
+
+  {VideoInfo::CS_YUV440    , "YUV440"},
+  {VideoInfo::CS_YUV440P10 , "YUV440P10"},
+  {VideoInfo::CS_YUV440P12 , "YUV440P12"},
+  {VideoInfo::CS_YUV440P14 , "YUV440P14"},
+  {VideoInfo::CS_YUV440P16 , "YUV440P16"},
+  {VideoInfo::CS_YUV440PS  , "YUV440PS"},
+
+  {VideoInfo::CS_YUVA440    , "YUVA440"},
+  {VideoInfo::CS_YUVA440P10 , "YUVA440P10"},
+  {VideoInfo::CS_YUVA440P12 , "YUVA440P12"},
+  {VideoInfo::CS_YUVA440P14 , "YUVA440P14"},
+  {VideoInfo::CS_YUVA440P16 , "YUVA440P16"},
+  {VideoInfo::CS_YUVA440PS  , "YUVA440PS"},
+
+  {VideoInfo::CS_YUV411P10 , "YUV411P10"},
+  {VideoInfo::CS_YUV411P12 , "YUV411P12"},
+  {VideoInfo::CS_YUV411P14 , "YUV411P14"},
+  {VideoInfo::CS_YUV411P16 , "YUV411P16"},
+  {VideoInfo::CS_YUV411PS  , "YUV411PS"},
+
+  {VideoInfo::CS_YUVA411    , "YUVA411"},
+  {VideoInfo::CS_YUVA411P10 , "YUVA411P10"},
+  {VideoInfo::CS_YUVA411P12 , "YUVA411P12"},
+  {VideoInfo::CS_YUVA411P14 , "YUVA411P14"},
+  {VideoInfo::CS_YUVA411P16 , "YUVA411P16"},
+  {VideoInfo::CS_YUVA411PS  , "YUVA411PS"},
+
+  {VideoInfo::CS_YUV410    , "YUV9"},
+  {VideoInfo::CS_YUV410P10 , "YUV410P10"},
+  {VideoInfo::CS_YUV410P12 , "YUV410P12"},
+  {VideoInfo::CS_YUV410P14 , "YUV410P14"},
+  {VideoInfo::CS_YUV410P16 , "YUV410P16"},
+  {VideoInfo::CS_YUV410PS  , "YUV410PS"},
+
+  {VideoInfo::CS_YUVA410P10 , "YUVA410P10"},
+  {VideoInfo::CS_YUVA410P12 , "YUVA410P12"},
+  {VideoInfo::CS_YUVA410P14 , "YUVA410P14"},
+  {VideoInfo::CS_YUVA410P16 , "YUVA410P16"},
+  {VideoInfo::CS_YUVA410PS  , "YUVA410PS"},
+
+  {VideoInfo::CS_YA8,  "YA8"},
+  {VideoInfo::CS_YA10, "YA10"},
+  {VideoInfo::CS_YA12, "YA12"},
+  {VideoInfo::CS_YA14, "YA14"},
+  {VideoInfo::CS_YA16, "YA16"},
+  {VideoInfo::CS_YA32, "YA32"}
 };
 
 static const std::multimap<int, std::string> pixel_format_table_ex =
@@ -1600,6 +1653,11 @@ static const std::multimap<int, std::string> pixel_format_table_ex =
   {VideoInfo::CS_YUVA420, "YUVA420P8"},
   {VideoInfo::CS_YUVA422, "YUVA422P8"},
   {VideoInfo::CS_YUVA444, "YUVA444P8"},
+  {VideoInfo::CS_YUV440 , "YUV440P8"},
+  {VideoInfo::CS_YUVA440, "YUVA440P8"},
+  {VideoInfo::CS_YUVA411, "YUVA411P8"},
+  {VideoInfo::CS_YUV410,  "YUV410P8"},
+  {VideoInfo::CS_YUVA410, "YUVA410P8"}
 };
 
 const char *GetPixelTypeName(const int pixel_type)
@@ -2894,3 +2952,7 @@ AVSValue ArraySort(AVSValue args, void* user_data, IScriptEnvironment* env)
   return AVSValue(new_val.data(), size);
 }
 
+AVSValue Is440(AVSValue args, void*, IScriptEnvironment*) {  return VI(args[0]).Is440(); }
+AVSValue IsYA(AVSValue args, void*, IScriptEnvironment*)  {  return VI(args[0]).IsYA(); }
+AVSValue Is410(AVSValue args, void*, IScriptEnvironment*) {  return VI(args[0]).Is410(); }
+AVSValue Is411(AVSValue args, void*, IScriptEnvironment*) {  return VI(args[0]).Is411(); }
diff --git a/avs_core/core/parser/script.h b/avs_core/core/parser/script.h
index 872af98bf..af6605d18 100644
--- a/avs_core/core/parser/script.h
+++ b/avs_core/core/parser/script.h
@@ -321,4 +321,9 @@ AVSValue ArrayIns(AVSValue args, void*, IScriptEnvironment* env);
 AVSValue ArrayDel(AVSValue args, void*, IScriptEnvironment* env);
 AVSValue ArraySort(AVSValue args, void*, IScriptEnvironment* env);
 
+AVSValue Is440(AVSValue args, void*, IScriptEnvironment* env);
+AVSValue IsYA(AVSValue args, void*, IScriptEnvironment* env);
+AVSValue Is410(AVSValue args, void*, IScriptEnvironment* env);
+AVSValue Is411(AVSValue args, void*, IScriptEnvironment* env);
+
 #endif  // __Script_H__
diff --git a/avs_core/include/avisynth.h b/avs_core/include/avisynth.h
index 84fa4f8da..5ac546be4 100644
--- a/avs_core/include/avisynth.h
+++ b/avs_core/include/avisynth.h
@@ -129,7 +129,7 @@ enum AvsVersion {
   AVISYNTH_CLASSIC_INTERFACE_VERSION_25 = 3,
   AVISYNTH_CLASSIC_INTERFACE_VERSION_26BETA = 5,
   AVISYNTH_CLASSIC_INTERFACE_VERSION = 6,
-  AVISYNTH_INTERFACE_VERSION = 12,
+  AVISYNTH_INTERFACE_VERSION = 13,
   AVISYNTHPLUS_INTERFACE_BUGFIX_VERSION = 0 // reset to zero whenever the normal interface version bumps
 };
 
@@ -480,6 +480,12 @@ struct AVS_Linkage {
   void          (VideoInfo::* SetChannelMask)(bool isChannelMaskKnown, unsigned int dwChannelMask);
   unsigned int  (VideoInfo::* GetChannelMask)() const;
 
+  // V13
+  bool          (VideoInfo::*Is440)() const;
+  bool          (VideoInfo::*IsYA)() const;
+  bool          (VideoInfo::*Is410)() const;
+  bool          (VideoInfo::*Is411)() const;
+
   /**********************************************************************/
   // Reserve pointer space for Avisynth+
   void          (VideoInfo::* reserved2[64 - 31])();
@@ -730,21 +736,28 @@ struct VideoInfo {
     CS_GENERIC_YUV422  = CS_PLANAR | CS_YUV | CS_VPlaneFirst | CS_Sub_Width_2 | CS_Sub_Height_1,  // 4:2:2 planar
     CS_GENERIC_YUV420  = CS_PLANAR | CS_YUV | CS_VPlaneFirst | CS_Sub_Width_2 | CS_Sub_Height_2,  // 4:2:0 planar
     CS_GENERIC_Y       = CS_PLANAR | CS_INTERLEAVED | CS_YUV,                                     // Y only (4:0:0)
+    CS_GENERIC_YA      = CS_PLANAR | CS_INTERLEAVED | CS_YUVA,                                    // Y plus alpha (4:0:0:A)
     CS_GENERIC_RGBP    = CS_PLANAR | CS_BGR | CS_RGB_TYPE,                                        // planar RGB. Though name is RGB but plane order G,B,R
     CS_GENERIC_RGBAP   = CS_PLANAR | CS_BGR | CS_RGBA_TYPE,                                       // planar RGBA
     CS_GENERIC_YUVA444 = CS_PLANAR | CS_YUVA | CS_VPlaneFirst | CS_Sub_Width_1 | CS_Sub_Height_1, // 4:4:4:A planar
     CS_GENERIC_YUVA422 = CS_PLANAR | CS_YUVA | CS_VPlaneFirst | CS_Sub_Width_2 | CS_Sub_Height_1, // 4:2:2:A planar
     CS_GENERIC_YUVA420 = CS_PLANAR | CS_YUVA | CS_VPlaneFirst | CS_Sub_Width_2 | CS_Sub_Height_2, // 4:2:0:A planar
+    CS_GENERIC_YUV440  = CS_PLANAR | CS_YUV  | CS_VPlaneFirst | CS_Sub_Width_1 | CS_Sub_Height_2, // 4:4:0 planar, 2026-07-29
+    CS_GENERIC_YUVA440 = CS_PLANAR | CS_YUVA | CS_VPlaneFirst | CS_Sub_Width_1 | CS_Sub_Height_2, // 4:4:0:A planar, 2026-07-29
+    CS_GENERIC_YUV411  = CS_PLANAR | CS_YUV  | CS_VPlaneFirst | CS_Sub_Width_4 | CS_Sub_Height_1, // 4:1:1 planar, 2026-08-25
+    CS_GENERIC_YUVA411 = CS_PLANAR | CS_YUVA | CS_VPlaneFirst | CS_Sub_Width_4 | CS_Sub_Height_1, // 4:1:1:A planar, 2026-08-25
+    CS_GENERIC_YUV410  = CS_PLANAR | CS_YUV  | CS_VPlaneFirst | CS_Sub_Width_4 | CS_Sub_Height_4, // 4:1:0 planar, 2026-08-25
+    CS_GENERIC_YUVA410 = CS_PLANAR | CS_YUVA | CS_VPlaneFirst | CS_Sub_Width_4 | CS_Sub_Height_4, // 4:1:0:A planar, 2026-08-25
 
     CS_YV24  = CS_GENERIC_YUV444 | CS_Sample_Bits_8,  // YVU 4:4:4 planar
     CS_YV16  = CS_GENERIC_YUV422 | CS_Sample_Bits_8,  // YVU 4:2:2 planar
     CS_YV12  = CS_GENERIC_YUV420 | CS_Sample_Bits_8,  // YVU 4:2:0 planar
     CS_I420  = CS_PLANAR | CS_YUV | CS_Sample_Bits_8 | CS_UPlaneFirst | CS_Sub_Width_2 | CS_Sub_Height_2,  // YUV 4:2:0 planar
     CS_IYUV  = CS_I420,
-    CS_YUV9  = CS_PLANAR | CS_YUV | CS_Sample_Bits_8 | CS_VPlaneFirst | CS_Sub_Width_4 | CS_Sub_Height_4,  // YUV 4:1:0 planar
-    CS_YV411 = CS_PLANAR | CS_YUV | CS_Sample_Bits_8 | CS_VPlaneFirst | CS_Sub_Width_4 | CS_Sub_Height_1,  // YUV 4:1:1 planar
+    CS_YUV9  = CS_GENERIC_YUV410 | CS_Sample_Bits_8,  // YUV 4:1:0 planar
+    CS_YV411 = CS_GENERIC_YUV411 | CS_Sample_Bits_8,  // YUV 4:1:1 planar
 
-    CS_Y8    = CS_GENERIC_Y | CS_Sample_Bits_8,                                                            // Y   4:0:0 planar
+    CS_Y8    = CS_GENERIC_Y | CS_Sample_Bits_8,       // Y   4:0:0 planar
 
     //-------------------------
     // AVS16: new planar constants go live! Experimental PF 160613
@@ -820,9 +833,62 @@ struct VideoInfo {
     CS_YUVA422P16 = CS_GENERIC_YUVA422 | CS_Sample_Bits_16, // YUVA 4:2:2 16bit samples
     CS_YUVA420P16 = CS_GENERIC_YUVA420 | CS_Sample_Bits_16, // YUVA 4:2:0 16bit samples
 
-    CS_YUVA444PS  = CS_GENERIC_YUVA444 | CS_Sample_Bits_32,  // YUVA 4:4:4 32bit samples
-    CS_YUVA422PS  = CS_GENERIC_YUVA422 | CS_Sample_Bits_32,  // YUVA 4:2:2 32bit samples
-    CS_YUVA420PS  = CS_GENERIC_YUVA420 | CS_Sample_Bits_32,  // YUVA 4:2:0 32bit samples
+    CS_YUVA444PS  = CS_GENERIC_YUVA444 | CS_Sample_Bits_32, // YUVA 4:4:4 32bit samples
+    CS_YUVA422PS  = CS_GENERIC_YUVA422 | CS_Sample_Bits_32, // YUVA 4:2:2 32bit samples
+    CS_YUVA420PS  = CS_GENERIC_YUVA420 | CS_Sample_Bits_32, // YUVA 4:2:0 32bit samples
+
+    // Planar YUV(A) 4:4:0, 2026-07-29
+    CS_YUV440     = CS_GENERIC_YUV440 | CS_Sample_Bits_8,  // YUV 4:4:0 8bit samples
+    CS_YUV440P10  = CS_GENERIC_YUV440 | CS_Sample_Bits_10, // YUV 4:4:0 10bit samples
+    CS_YUV440P12  = CS_GENERIC_YUV440 | CS_Sample_Bits_12, // YUV 4:4:0 12bit samples
+    CS_YUV440P14  = CS_GENERIC_YUV440 | CS_Sample_Bits_14, // YUV 4:4:0 14bit samples
+    CS_YUV440P16  = CS_GENERIC_YUV440 | CS_Sample_Bits_16, // YUV 4:4:0 16bit samples
+    CS_YUV440PS   = CS_GENERIC_YUV440 | CS_Sample_Bits_32, // YUV 4:4:0 32bit samples
+
+    CS_YUVA440    = CS_GENERIC_YUVA440 | CS_Sample_Bits_8,  // YUVA 4:4:0 8bit samples
+    CS_YUVA440P10 = CS_GENERIC_YUVA440 | CS_Sample_Bits_10, // YUVA 4:4:0 10bit samples
+    CS_YUVA440P12 = CS_GENERIC_YUVA440 | CS_Sample_Bits_12, // YUVA 4:4:0 12bit samples
+    CS_YUVA440P14 = CS_GENERIC_YUVA440 | CS_Sample_Bits_14, // YUVA 4:4:0 14bit samples
+    CS_YUVA440P16 = CS_GENERIC_YUVA440 | CS_Sample_Bits_16, // YUVA 4:4:0 16bit samples
+    CS_YUVA440PS  = CS_GENERIC_YUVA440 | CS_Sample_Bits_32, // YUVA 4:4:0 32bit samples
+
+    // Planar YUV(A) 4:1:1 additional bitdepths, 2026-08-25
+    CS_YUV411     = CS_YV411,                              // YUV 4:1:1 8bit samples
+    CS_YUV411P10  = CS_GENERIC_YUV411 | CS_Sample_Bits_10, // YUV 4:1:1 10bit samples
+    CS_YUV411P12  = CS_GENERIC_YUV411 | CS_Sample_Bits_12, // YUV 4:1:1 12bit samples
+    CS_YUV411P14  = CS_GENERIC_YUV411 | CS_Sample_Bits_14, // YUV 4:1:1 14bit samples
+    CS_YUV411P16  = CS_GENERIC_YUV411 | CS_Sample_Bits_16, // YUV 4:1:1 16bit samples
+    CS_YUV411PS   = CS_GENERIC_YUV411 | CS_Sample_Bits_32, // YUV 4:1:1 32bit samples
+
+    CS_YUVA411    = CS_GENERIC_YUVA411 | CS_Sample_Bits_8,  // YUVA 4:1:1 8bit samples
+    CS_YUVA411P10 = CS_GENERIC_YUVA411 | CS_Sample_Bits_10, // YUVA 4:1:1 10bit samples
+    CS_YUVA411P12 = CS_GENERIC_YUVA411 | CS_Sample_Bits_12, // YUVA 4:1:1 12bit samples
+    CS_YUVA411P14 = CS_GENERIC_YUVA411 | CS_Sample_Bits_14, // YUVA 4:1:1 14bit samples
+    CS_YUVA411P16 = CS_GENERIC_YUVA411 | CS_Sample_Bits_16, // YUVA 4:1:1 16bit samples
+    CS_YUVA411PS  = CS_GENERIC_YUVA411 | CS_Sample_Bits_32, // YUVA 4:1:1 32bit samples
+
+    // Planar YUV(A) 4:1:0, 2026-08-25
+    CS_YUV410     = CS_YUV9,                               // YUV 4:1:0 8bit samples
+    CS_YUV410P10  = CS_GENERIC_YUV410 | CS_Sample_Bits_10, // YUV 4:1:0 10bit samples
+    CS_YUV410P12  = CS_GENERIC_YUV410 | CS_Sample_Bits_12, // YUV 4:1:0 12bit samples
+    CS_YUV410P14  = CS_GENERIC_YUV410 | CS_Sample_Bits_14, // YUV 4:1:0 14bit samples
+    CS_YUV410P16  = CS_GENERIC_YUV410 | CS_Sample_Bits_16, // YUV 4:1:0 16bit samples
+    CS_YUV410PS   = CS_GENERIC_YUV410 | CS_Sample_Bits_32, // YUV 4:1:0 32bit samples
+
+    CS_YUVA410    = CS_GENERIC_YUVA410 | CS_Sample_Bits_8,  // YUVA 4:1:0 8bit samples
+    CS_YUVA410P10 = CS_GENERIC_YUVA410 | CS_Sample_Bits_10, // YUVA 4:1:0 10bit samples
+    CS_YUVA410P12 = CS_GENERIC_YUVA410 | CS_Sample_Bits_12, // YUVA 4:1:0 12bit samples
+    CS_YUVA410P14 = CS_GENERIC_YUVA410 | CS_Sample_Bits_14, // YUVA 4:1:0 14bit samples
+    CS_YUVA410P16 = CS_GENERIC_YUVA410 | CS_Sample_Bits_16, // YUVA 4:1:0 16bit samples
+    CS_YUVA410PS  = CS_GENERIC_YUVA410 | CS_Sample_Bits_32, // YUVA 4:1:0 32bit samples
+
+    // Y plus alpha 4:0:0, 2026-08-25
+    CS_YA8  = CS_GENERIC_YA | CS_Sample_Bits_8,  // Y plus alpha 4:0:0 8bit samples
+    CS_YA10 = CS_GENERIC_YA | CS_Sample_Bits_10, // Y plus alpha 4:0:0 10bit samples
+    CS_YA12 = CS_GENERIC_YA | CS_Sample_Bits_12, // Y plus alpha 4:0:0 12bit samples
+    CS_YA14 = CS_GENERIC_YA | CS_Sample_Bits_14, // Y plus alpha 4:0:0 14bit samples
+    CS_YA16 = CS_GENERIC_YA | CS_Sample_Bits_16, // Y plus alpha 4:0:0 16bit samples
+    CS_YA32 = CS_GENERIC_YA | CS_Sample_Bits_32  // Y plus alpha 4:0:0 32bit samples
   };
 
   int pixel_type;                // changed to int as of 2.5
@@ -992,6 +1058,12 @@ struct VideoInfo {
   void SetChannelMask(bool isChannelMaskKnown, unsigned int dwChannelMask) AVS_BakedCode(AVS_LinkCall_Void(SetChannelMask)(isChannelMaskKnown, dwChannelMask))
   unsigned int GetChannelMask() const AVS_BakedCode(return AVS_LinkCallOptDefault(GetChannelMask, 0) )
 
+  // v13
+  bool Is440() const AVS_BakedCode( return AVS_LinkCallOptDefault(Is440, false) )
+  bool IsYA() const AVS_BakedCode( return AVS_LinkCallOptDefault(IsYA, false) )
+  bool Is410() const AVS_BakedCode( return AVS_LinkCallOptDefault(Is410, false) )
+  bool Is411() const AVS_BakedCode( return AVS_LinkCallOpt(Is410, IsYV411) )
+
 }; // end struct VideoInfo
 
 
diff --git a/avs_core/include/avisynth_c.h b/avs_core/include/avisynth_c.h
index 8d7d71f56..5fefc8d6b 100644
--- a/avs_core/include/avisynth_c.h
+++ b/avs_core/include/avisynth_c.h
@@ -167,7 +167,7 @@
 #ifndef __AVISYNTH_12_H__
 enum {
   AVISYNTH_INTERFACE_CLASSIC_VERSION = 6,
-  AVISYNTH_INTERFACE_VERSION = 12,
+  AVISYNTH_INTERFACE_VERSION = 13,
   AVISYNTHPLUS_INTERFACE_BUGFIX_VERSION = 0 // reset to zero whenever the normal interface version bumps
 };
 #endif
@@ -239,15 +239,22 @@ enum {
   AVS_CS_RGB_TYPE  = 1 << 0,
   AVS_CS_RGBA_TYPE = 1 << 1,
 
-  AVS_CS_GENERIC_YUV444  = AVS_CS_PLANAR | AVS_CS_YUV | AVS_CS_VPLANEFIRST | AVS_CS_SUB_WIDTH_1 | AVS_CS_SUB_HEIGHT_1,  // 4:4:4 planar
-  AVS_CS_GENERIC_YUV422  = AVS_CS_PLANAR | AVS_CS_YUV | AVS_CS_VPLANEFIRST | AVS_CS_SUB_WIDTH_2 | AVS_CS_SUB_HEIGHT_1,  // 4:2:2 planar
-  AVS_CS_GENERIC_YUV420  = AVS_CS_PLANAR | AVS_CS_YUV | AVS_CS_VPLANEFIRST | AVS_CS_SUB_WIDTH_2 | AVS_CS_SUB_HEIGHT_2,  // 4:2:0 planar
+  AVS_CS_GENERIC_YUV444  = AVS_CS_PLANAR | AVS_CS_YUV  | AVS_CS_VPLANEFIRST | AVS_CS_SUB_WIDTH_1 | AVS_CS_SUB_HEIGHT_1, // 4:4:4 planar
+  AVS_CS_GENERIC_YUV422  = AVS_CS_PLANAR | AVS_CS_YUV  | AVS_CS_VPLANEFIRST | AVS_CS_SUB_WIDTH_2 | AVS_CS_SUB_HEIGHT_1, // 4:2:2 planar
+  AVS_CS_GENERIC_YUV420  = AVS_CS_PLANAR | AVS_CS_YUV  | AVS_CS_VPLANEFIRST | AVS_CS_SUB_WIDTH_2 | AVS_CS_SUB_HEIGHT_2, // 4:2:0 planar
   AVS_CS_GENERIC_Y       = AVS_CS_PLANAR | AVS_CS_INTERLEAVED | AVS_CS_YUV,                                             // Y only (4:0:0)
-  AVS_CS_GENERIC_RGBP    = AVS_CS_PLANAR | AVS_CS_BGR | AVS_CS_RGB_TYPE,                                                // planar RGB
-  AVS_CS_GENERIC_RGBAP   = AVS_CS_PLANAR | AVS_CS_BGR | AVS_CS_RGBA_TYPE,                                               // planar RGBA
+  AVS_CS_GENERIC_YA      = AVS_CS_PLANAR | AVS_CS_INTERLEAVED | AVS_CS_YUVA,                                            // Y plus alpha (4:0:0:A)
+  AVS_CS_GENERIC_RGBP    = AVS_CS_PLANAR | AVS_CS_BGR  | AVS_CS_RGB_TYPE,                                               // planar RGB
+  AVS_CS_GENERIC_RGBAP   = AVS_CS_PLANAR | AVS_CS_BGR  | AVS_CS_RGBA_TYPE,                                              // planar RGBA
   AVS_CS_GENERIC_YUVA444 = AVS_CS_PLANAR | AVS_CS_YUVA | AVS_CS_VPLANEFIRST | AVS_CS_SUB_WIDTH_1 | AVS_CS_SUB_HEIGHT_1, // 4:4:4:A planar
   AVS_CS_GENERIC_YUVA422 = AVS_CS_PLANAR | AVS_CS_YUVA | AVS_CS_VPLANEFIRST | AVS_CS_SUB_WIDTH_2 | AVS_CS_SUB_HEIGHT_1, // 4:2:2:A planar
-  AVS_CS_GENERIC_YUVA420 = AVS_CS_PLANAR | AVS_CS_YUVA | AVS_CS_VPLANEFIRST | AVS_CS_SUB_WIDTH_2 | AVS_CS_SUB_HEIGHT_2  // 4:2:0:A planar
+  AVS_CS_GENERIC_YUVA420 = AVS_CS_PLANAR | AVS_CS_YUVA | AVS_CS_VPLANEFIRST | AVS_CS_SUB_WIDTH_2 | AVS_CS_SUB_HEIGHT_2, // 4:2:0:A planar
+  AVS_CS_GENERIC_YUV440  = AVS_CS_PLANAR | AVS_CS_YUV  | AVS_CS_VPLANEFIRST | AVS_CS_SUB_WIDTH_1 | AVS_CS_SUB_HEIGHT_2, // 4:4:0 planar
+  AVS_CS_GENERIC_YUVA440 = AVS_CS_PLANAR | AVS_CS_YUVA | AVS_CS_VPLANEFIRST | AVS_CS_SUB_WIDTH_1 | AVS_CS_SUB_HEIGHT_2, // 4:4:0:A planar
+  AVS_CS_GENERIC_YUV411  = AVS_CS_PLANAR | AVS_CS_YUV  | AVS_CS_VPLANEFIRST | AVS_CS_SUB_WIDTH_4 | AVS_CS_SUB_HEIGHT_1, // 4:1:1 planar
+  AVS_CS_GENERIC_YUVA411 = AVS_CS_PLANAR | AVS_CS_YUVA | AVS_CS_VPLANEFIRST | AVS_CS_SUB_WIDTH_4 | AVS_CS_SUB_HEIGHT_1, // 4:1:1:A planar
+  AVS_CS_GENERIC_YUV410  = AVS_CS_PLANAR | AVS_CS_YUV  | AVS_CS_VPLANEFIRST | AVS_CS_SUB_WIDTH_4 | AVS_CS_SUB_HEIGHT_4, // 4:1:0 planar
+  AVS_CS_GENERIC_YUVA410 = AVS_CS_PLANAR | AVS_CS_YUVA | AVS_CS_VPLANEFIRST | AVS_CS_SUB_WIDTH_4 | AVS_CS_SUB_HEIGHT_4  // 4:1:0:A planar
 };
 
 // Specific color formats
@@ -265,8 +272,8 @@ enum {
   AVS_CS_YV12  = AVS_CS_GENERIC_YUV420 | AVS_CS_SAMPLE_BITS_8,  // YUV 4:2:0 planar
   AVS_CS_I420  = AVS_CS_PLANAR | AVS_CS_YUV | AVS_CS_SAMPLE_BITS_8 | AVS_CS_UPLANEFIRST | AVS_CS_SUB_WIDTH_2 | AVS_CS_SUB_HEIGHT_2,  // YUV 4:2:0 planar
   AVS_CS_IYUV  = AVS_CS_I420,
-  AVS_CS_YV411 = AVS_CS_PLANAR | AVS_CS_YUV | AVS_CS_SAMPLE_BITS_8 | AVS_CS_VPLANEFIRST | AVS_CS_SUB_WIDTH_4 | AVS_CS_SUB_HEIGHT_1,  // YUV 4:1:1 planar
-  AVS_CS_YUV9  = AVS_CS_PLANAR | AVS_CS_YUV | AVS_CS_SAMPLE_BITS_8 | AVS_CS_VPLANEFIRST | AVS_CS_SUB_WIDTH_4 | AVS_CS_SUB_HEIGHT_4,  // YUV 4:1:0 planar
+  AVS_CS_YV411 = AVS_CS_GENERIC_YUV411 | AVS_CS_SAMPLE_BITS_8,  // YUV 4:1:1 planar
+  AVS_CS_YUV9  = AVS_CS_GENERIC_YUV410 | AVS_CS_SAMPLE_BITS_8,  // YUV 4:1:0 planar
   AVS_CS_Y8    = AVS_CS_GENERIC_Y | AVS_CS_SAMPLE_BITS_8,       // Y   4:0:0 planar
 
   //-------------------------
@@ -299,8 +306,8 @@ enum {
   AVS_CS_Y32      = AVS_CS_GENERIC_Y | AVS_CS_SAMPLE_BITS_32,       // Y   4:0:0 32bit samples
 
   // RGB packed
-  AVS_CS_BGR48 = AVS_CS_RGB_TYPE | AVS_CS_BGR | AVS_CS_INTERLEAVED | AVS_CS_SAMPLE_BITS_16,    // BGR 3x16 bit
-  AVS_CS_BGR64 = AVS_CS_RGBA_TYPE | AVS_CS_BGR | AVS_CS_INTERLEAVED | AVS_CS_SAMPLE_BITS_16,    // BGR 4x16 bit
+  AVS_CS_BGR48 = AVS_CS_RGB_TYPE | AVS_CS_BGR | AVS_CS_INTERLEAVED | AVS_CS_SAMPLE_BITS_16,  // BGR 3x16 bit
+  AVS_CS_BGR64 = AVS_CS_RGBA_TYPE | AVS_CS_BGR | AVS_CS_INTERLEAVED | AVS_CS_SAMPLE_BITS_16, // BGR 4x16 bit
   // no packed 32 bit (float) support for these legacy types
 
   // RGB planar
@@ -340,9 +347,62 @@ enum {
   AVS_CS_YUVA422P16 = AVS_CS_GENERIC_YUVA422 | AVS_CS_SAMPLE_BITS_16, // YUVA 4:2:2 16bit samples
   AVS_CS_YUVA420P16 = AVS_CS_GENERIC_YUVA420 | AVS_CS_SAMPLE_BITS_16, // YUVA 4:2:0 16bit samples
 
-  AVS_CS_YUVA444PS  = AVS_CS_GENERIC_YUVA444 | AVS_CS_SAMPLE_BITS_32,  // YUVA 4:4:4 32bit samples
-  AVS_CS_YUVA422PS  = AVS_CS_GENERIC_YUVA422 | AVS_CS_SAMPLE_BITS_32,  // YUVA 4:2:2 32bit samples
-  AVS_CS_YUVA420PS  = AVS_CS_GENERIC_YUVA420 | AVS_CS_SAMPLE_BITS_32,  // YUVA 4:2:0 32bit samples
+  AVS_CS_YUVA444PS  = AVS_CS_GENERIC_YUVA444 | AVS_CS_SAMPLE_BITS_32, // YUVA 4:4:4 32bit samples
+  AVS_CS_YUVA422PS  = AVS_CS_GENERIC_YUVA422 | AVS_CS_SAMPLE_BITS_32, // YUVA 4:2:2 32bit samples
+  AVS_CS_YUVA420PS  = AVS_CS_GENERIC_YUVA420 | AVS_CS_SAMPLE_BITS_32, // YUVA 4:2:0 32bit samples
+
+  // Planar YUV(A) 4:4:0 - 2026-07-29
+  AVS_CS_YUV440     = AVS_CS_GENERIC_YUV440 | AVS_CS_SAMPLE_BITS_8,   // YUV 4:4:0 8bit samples
+  AVS_CS_YUV440P10  = AVS_CS_GENERIC_YUV440 | AVS_CS_SAMPLE_BITS_10,  // YUV 4:4:0 10bit samples
+  AVS_CS_YUV440P12  = AVS_CS_GENERIC_YUV440 | AVS_CS_SAMPLE_BITS_12,  // YUV 4:4:0 12bit samples
+  AVS_CS_YUV440P14  = AVS_CS_GENERIC_YUV440 | AVS_CS_SAMPLE_BITS_14,  // YUV 4:4:0 14bit samples
+  AVS_CS_YUV440P16  = AVS_CS_GENERIC_YUV440 | AVS_CS_SAMPLE_BITS_16,  // YUV 4:4:0 16bit samples
+  AVS_CS_YUV440PS   = AVS_CS_GENERIC_YUV440 | AVS_CS_SAMPLE_BITS_32,  // YUV 4:4:0 32bit samples
+
+  AVS_CS_YUVA440    = AVS_CS_GENERIC_YUVA440 | AVS_CS_SAMPLE_BITS_8,  // YUVA 4:4:0 8bit samples
+  AVS_CS_YUVA440P10 = AVS_CS_GENERIC_YUVA440 | AVS_CS_SAMPLE_BITS_10, // YUVA 4:4:0 10bit samples
+  AVS_CS_YUVA440P12 = AVS_CS_GENERIC_YUVA440 | AVS_CS_SAMPLE_BITS_12, // YUVA 4:4:0 12bit samples
+  AVS_CS_YUVA440P14 = AVS_CS_GENERIC_YUVA440 | AVS_CS_SAMPLE_BITS_14, // YUVA 4:4:0 14bit samples
+  AVS_CS_YUVA440P16 = AVS_CS_GENERIC_YUVA440 | AVS_CS_SAMPLE_BITS_16, // YUVA 4:4:0 16bit samples
+  AVS_CS_YUVA440PS  = AVS_CS_GENERIC_YUVA440 | AVS_CS_SAMPLE_BITS_32, // YUVA 4:4:0 32bit samples
+
+  // Planar YUV(A) 4:1:1 additional formats - 2026-08-25
+  AVS_CS_YUV411     = AVS_CS_YV411,                                   // YUV 4:1:1 10bit samples
+  AVS_CS_YUV411P10  = AVS_CS_GENERIC_YUV411 | AVS_CS_SAMPLE_BITS_10,  // YUV 4:1:1 10bit samples
+  AVS_CS_YUV411P12  = AVS_CS_GENERIC_YUV411 | AVS_CS_SAMPLE_BITS_12,  // YUV 4:1:1 12bit samples
+  AVS_CS_YUV411P14  = AVS_CS_GENERIC_YUV411 | AVS_CS_SAMPLE_BITS_14,  // YUV 4:1:1 14bit samples
+  AVS_CS_YUV411P16  = AVS_CS_GENERIC_YUV411 | AVS_CS_SAMPLE_BITS_16,  // YUV 4:1:1 16bit samples
+  AVS_CS_YUV411PS   = AVS_CS_GENERIC_YUV411 | AVS_CS_SAMPLE_BITS_32,  // YUV 4:1:1 32bit samples
+
+  AVS_CS_YUVA411    = AVS_CS_GENERIC_YUVA411 | AVS_CS_SAMPLE_BITS_8,  // YUVA 4:1:1 8bit samples
+  AVS_CS_YUVA411P10 = AVS_CS_GENERIC_YUVA411 | AVS_CS_SAMPLE_BITS_10, // YUVA 4:1:1 10bit samples
+  AVS_CS_YUVA411P12 = AVS_CS_GENERIC_YUVA411 | AVS_CS_SAMPLE_BITS_12, // YUVA 4:1:1 12bit samples
+  AVS_CS_YUVA411P14 = AVS_CS_GENERIC_YUVA411 | AVS_CS_SAMPLE_BITS_14, // YUVA 4:1:1 14bit samples
+  AVS_CS_YUVA411P16 = AVS_CS_GENERIC_YUVA411 | AVS_CS_SAMPLE_BITS_16, // YUVA 4:1:1 16bit samples
+  AVS_CS_YUVA411PS  = AVS_CS_GENERIC_YUVA411 | AVS_CS_SAMPLE_BITS_32, // YUVA 4:1:1 32bit samples
+
+  // Planar YUV(A) 4:1:0 - 2026-08-25
+  AVS_CS_YUV410     = AVS_CS_YUV9,                                    // YUV 4:1:0 8bit samples
+  AVS_CS_YUV410P10  = AVS_CS_GENERIC_YUV410 | AVS_CS_SAMPLE_BITS_10,  // YUV 4:1:0 10bit samples
+  AVS_CS_YUV410P12  = AVS_CS_GENERIC_YUV410 | AVS_CS_SAMPLE_BITS_12,  // YUV 4:1:0 12bit samples
+  AVS_CS_YUV410P14  = AVS_CS_GENERIC_YUV410 | AVS_CS_SAMPLE_BITS_14,  // YUV 4:1:0 14bit samples
+  AVS_CS_YUV410P16  = AVS_CS_GENERIC_YUV410 | AVS_CS_SAMPLE_BITS_16,  // YUV 4:1:0 16bit samples
+  AVS_CS_YUV410PS   = AVS_CS_GENERIC_YUV410 | AVS_CS_SAMPLE_BITS_32,  // YUV 4:1:0 32bit samples
+
+  AVS_CS_YUVA410    = AVS_CS_GENERIC_YUVA410 | AVS_CS_SAMPLE_BITS_8,  // YUVA 4:1:0 8bit samples
+  AVS_CS_YUVA410P10 = AVS_CS_GENERIC_YUVA410 | AVS_CS_SAMPLE_BITS_10, // YUVA 4:1:0 10bit samples
+  AVS_CS_YUVA410P12 = AVS_CS_GENERIC_YUVA410 | AVS_CS_SAMPLE_BITS_12, // YUVA 4:1:0 12bit samples
+  AVS_CS_YUVA410P14 = AVS_CS_GENERIC_YUVA410 | AVS_CS_SAMPLE_BITS_14, // YUVA 4:1:0 14bit samples
+  AVS_CS_YUVA410P16 = AVS_CS_GENERIC_YUVA410 | AVS_CS_SAMPLE_BITS_16, // YUVA 4:1:0 16bit samples
+  AVS_CS_YUVA410PS  = AVS_CS_GENERIC_YUVA410 | AVS_CS_SAMPLE_BITS_32, // YUVA 4:1:0 32bit samples
+
+  // Y plus alpha 4:0:0 - 2026-08-25
+  AVS_CS_YA8  = AVS_CS_GENERIC_YA | AVS_CS_SAMPLE_BITS_8,  // Y plus alpha 4:0:0 planar 8bit samples
+  AVS_CS_YA10 = AVS_CS_GENERIC_YA | AVS_CS_SAMPLE_BITS_10, // Y plus alpha 4:0:0 planar 10bit samples
+  AVS_CS_YA12 = AVS_CS_GENERIC_YA | AVS_CS_SAMPLE_BITS_12, // Y plus alpha 4:0:0 planar 12bit samples
+  AVS_CS_YA14 = AVS_CS_GENERIC_YA | AVS_CS_SAMPLE_BITS_14, // Y plus alpha 4:0:0 planar 14bit samples
+  AVS_CS_YA16 = AVS_CS_GENERIC_YA | AVS_CS_SAMPLE_BITS_16, // Y plus alpha 4:0:0 planar 16bit samples
+  AVS_CS_YA32 = AVS_CS_GENERIC_YA | AVS_CS_SAMPLE_BITS_32  // Y plus alpha 4:0:0 planar 32bit samples
 };
 
 // AvsChannelMask enum: Unshifted channel mask constants like in WAVEFORMATEXTENSIBLE
@@ -823,6 +883,15 @@ AVSC_API(void, avs_set_channel_mask)(const AVS_VideoInfo* p, bool isChannelMaskK
 
 AVSC_API(unsigned int, avs_get_channel_mask)(const AVS_VideoInfo* p);
 
+// V13
+AVSC_API(int, avs_is_440)(const AVS_VideoInfo * p);
+
+AVSC_API(int, avs_is_ya)(const AVS_VideoInfo * p);
+
+AVSC_API(int, avs_is_410)(const AVS_VideoInfo * p);
+
+AVSC_API(int, avs_is_411)(const AVS_VideoInfo * p);
+
 // end of Avisynth+ specific
 
 /////////////////////////////////////////////////////////////////////
@@ -1708,6 +1777,11 @@ struct AVS_Library {
   AVSC_DECLARE_FUNC(avs_acquire_global_lock);
   AVSC_DECLARE_FUNC(avs_release_global_lock);
   AVSC_DECLARE_FUNC(avs_get_cpu_flags_ex);
+  // V13
+  AVSC_DECLARE_FUNC(avs_is_440);
+  AVSC_DECLARE_FUNC(avs_is_ya);
+  AVSC_DECLARE_FUNC(avs_is_410);
+  AVSC_DECLARE_FUNC(avs_is_411);
 };
 
 #undef AVSC_DECLARE_FUNC
@@ -2001,6 +2075,11 @@ avs_bits_per_component    constant 8 (8 bits/component)
   AVSC_LOAD_FUNC_OPT(avs_acquire_global_lock);
   AVSC_LOAD_FUNC_OPT(avs_release_global_lock);
   AVSC_LOAD_FUNC_OPT(avs_get_cpu_flags_ex);
+  // V13
+  AVSC_LOAD_FUNC_OPT(avs_is_440);
+  AVSC_LOAD_FUNC_OPT(avs_is_ya);
+  AVSC_LOAD_FUNC_OPT(avs_is_410);
+  AVSC_LOAD_FUNC_OPT(avs_is_411);
 
 #undef __AVSC_STRINGIFY
 #undef AVSC_STRINGIFY
diff --git a/distrib/docs/english/source/avisynthdoc/FilterSDK/C_api.rst b/distrib/docs/english/source/avisynthdoc/FilterSDK/C_api.rst
index 1a74729f7..fdbb16238 100644
--- a/distrib/docs/english/source/avisynthdoc/FilterSDK/C_api.rst
+++ b/distrib/docs/english/source/avisynthdoc/FilterSDK/C_api.rst
@@ -413,6 +413,14 @@ Quick list
 +-------------------------------------+-----------------------+-------+
 | avs_get_cpu_flags_ex                | AVS_ScriptEnvironment | 12    |
 +-------------------------------------+-----------------------+-------+
+| avs_is_440                          | AVS_VideoInfo         | 13    |
++-------------------------------------+-----------------------+-------+
+| avs_is_410                          | AVS_VideoInfo         | 13    |
++-------------------------------------+-----------------------+-------+
+| avs_is_411                          | AVS_VideoInfo         | 13    |
++-------------------------------------+-----------------------+-------+
+| avs_is_ya                           | AVS_VideoInfo         | 13    |
++-------------------------------------+-----------------------+-------+
 
 
 Reference
@@ -1113,6 +1121,26 @@ avs_is_rgb48
 avs_is_rgb64
 ------------
 
+.. _c_avs_is_440:
+
+avs_is_440
+----------
+
+.. _c_avs_is_410:
+
+avs_is_410
+----------
+
+.. _c_avs_is_411:
+
+avs_is_411
+----------
+
+.. _c_avs_is_ya:
+
+avs_is_ya
+---------
+
 .. _c_avs_subframe_planar_a:
 
 avs_subframe_planar_a
@@ -1726,4 +1754,4 @@ ____
 
 Back to :doc:`FilterSDK`
 
-$Date: 2025/02/24 13:53:00 $
+$Date: 2026/08/25 22:52:00 $
diff --git a/distrib/docs/english/source/avisynthdoc/FilterSDK/FilterSDK.rst b/distrib/docs/english/source/avisynthdoc/FilterSDK/FilterSDK.rst
index e8ff6fe2c..e0863a84a 100644
--- a/distrib/docs/english/source/avisynthdoc/FilterSDK/FilterSDK.rst
+++ b/distrib/docs/english/source/avisynthdoc/FilterSDK/FilterSDK.rst
@@ -467,6 +467,18 @@ What's new in the API V12
           
           see :ref:`ApplyMessageEx<cplusplus_applymessage>`
 
+.. _api_v13_whats_new:
+
+What's new in the API V13
+-------------------------
+
+- C and C++ API (AVISYNTH_INTERFACE_VERSION = 13):
+        - New API functions for additional pixel formats:
+
+          * ``avs_is_440``, ``avs_is_410``, ``avs_is_411``, ``avs_is_ya`` (C)
+          * ``Is440``, ``Is410``, ``Is411``, ``IsYA`` (C++)
+
+
 Some history
 ------------
 
@@ -494,7 +506,7 @@ License terms
 
 Note: Avisynth Filter SDK parts are under specific :doc:`SDK license <SDKLicense>` terms.
 
-$Date: 2025/12/02 15:36:00 $
+$Date: 2026/08/25 22:40:00 $
 
 Latest online Avisynth+ version is at https://avisynthplus.readthedocs.io/en/latest/avisynthdoc/FilterSDK/FilterSDK.html
 This one is maintained properly.
diff --git a/distrib/docs/english/source/avisynthdoc/FilterSDK/VideoInfo.rst b/distrib/docs/english/source/avisynthdoc/FilterSDK/VideoInfo.rst
index 747e6dbfc..3e67692ca 100644
--- a/distrib/docs/english/source/avisynthdoc/FilterSDK/VideoInfo.rst
+++ b/distrib/docs/english/source/avisynthdoc/FilterSDK/VideoInfo.rst
@@ -395,6 +395,23 @@ These functions are the bit depth independent versions of
 IsYV24, IsYV16, IsYV12 and IsY8.
 
 
+Is440 / Is410 / Is411 / IsYA (AviSynth+)
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+Added in v13:
+
+::
+
+    bool Is440() const;
+    bool Is410() const;
+    bool Is411() const;
+    bool IsYA() const;
+
+These functions will return true if the clip has the specific YUV colorspace.
+Is440, Is410, and Is411 also return true for alpha-bearing variants.  IsYA
+is the alpha-bearing version.
+
+
 IsYUVA / IsPlanarRGB / IsPlanarRGBA (AviSynth+)
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 
@@ -937,7 +954,7 @@ only 8, 10, 12, 14, 16 and 32.
 
 Back to :doc:`FilterSDK`
 
-$Date: 2023/02/15 12:28:50 $
+$Date: 2025/08/25 22:52:15 $
 
 .. _RGB: http://avisynth.nl/index.php/RGB
 .. _BMP frame: http://en.wikipedia.org/wiki/BMP_file_format
diff --git a/distrib/docs/english/source/avisynthdoc/changelist376.rst b/distrib/docs/english/source/avisynthdoc/changelist376.rst
index ded559b30..2df622e3d 100644
--- a/distrib/docs/english/source/avisynthdoc/changelist376.rst
+++ b/distrib/docs/english/source/avisynthdoc/changelist376.rst
@@ -3,6 +3,17 @@ Changes from 3.7.5 to 3.7.6
 
 Additions, changes
 ~~~~~~~~~~~~~~~~~~
+- Added new pixel format constants
+
+  * YUV(A) 4:4:0(:α) 8~32bits
+  * YV411 aliased to more standard YUV411 naming
+  * YUV 4:1:1 10~32bits
+  * YUVA 4:1:1:α 8~32bits
+  * Y plus alpha 4:0:0:α 8~32bits
+  * YUV9 (added in 2.6 but not used except in the constants list) aliased to more standard YUV410 naming
+  * YUV 4:1:0 10~32bits
+  * YUVA 4:1:0:α 8~32bits
+
 - Added ``SetFilterProp``, ``GetFilterProps``, and ``SetFilterPropPassthrough``:
 
   * ``SetFilterProp`` — automatically inject a frame property on the output of a named filter
@@ -173,6 +184,7 @@ Additions, changes
 
 Build environment, Interface
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+- Bump to interface version 13 for new color constants
 - introduce ``AVS_RESTRICT`` to ``avs/config.h`` (compiler invariant c++ ``__restrict``)
 - AVX512: CMake to recognize ``*_avx512b.*`` and ``*_avx512.*`` file pattern, add compiler specific AVX512 
   compile flags accordingly (AVX512 Base and Ice Lake extensions)
diff --git a/distrib/docs/english/source/avisynthdoc/syntax/syntax_clip_properties.rst b/distrib/docs/english/source/avisynthdoc/syntax/syntax_clip_properties.rst
index 651a600a7..eabed8ef8 100644
--- a/distrib/docs/english/source/avisynthdoc/syntax/syntax_clip_properties.rst
+++ b/distrib/docs/english/source/avisynthdoc/syntax/syntax_clip_properties.rst
@@ -247,11 +247,30 @@ WAVE_FORMAT_EXTENSIBLE dwChannelMask speaker position definitions, see
 https://learn.microsoft.com/en-us/windows/win32/api/mmreg/ns-mmreg-waveformatextensible
 (type: int)
 
+-   Is440 (clip) (v3.7.6)
+
+Returns true if the clip is 4:4:0, false otherwise (type: bool).
+
+-   Is410 (clip) (v3.7.6)
+
+Returns true if the clip is 4:1:0, false otherwise (type: bool).
+
+-   Is411 (clip) (v3.7.6)
+
+Returns true if the clip is 4:1:1 (like IsYV411, but bit depth
+independently), false otherwise (type: bool).
+
+-   IsYA (clip) (v3.7.6)
+
+Returns true if the clip is 4:0:0:α, false otherwise (type: bool).
+
+
+
 --------
 
 Back to :doc:`AviSynth Syntax <syntax_ref>`.
 
-$Date: 2025-02-25 17:08:52-05:00 $
+$Date: 2026-08-25 22:50:00-05:00 $
 
 .. _rgb: http://avisynth.nl/index.php/RGB
 .. _rgb24: http://avisynth.nl/index.php/RGB24