ltx-2.3-i2v: expose DURATION_SECONDS constant (node 340) with 10s ceiling clamp

workflows/ltx-2.3-i2v.json

@@ -196,7 +196,7 @@
           "widget": {
             "name": "value_4"
           },
-          "link": null
+          "link": 634
         },
         {
           "label": "fps",
@@ -337,6 +337,74 @@
         }
       },
       "widgets_values": []
+    },
+    {
+      "id": 340,
+      "type": "PrimitiveInt",
+      "pos": [
+        -560,
+        340
+      ],
+      "size": [
+        340,
+        90
+      ],
+      "flags": {},
+      "order": 0,
+      "mode": 0,
+      "inputs": [
+        {
+          "localized_name": "value",
+          "name": "value",
+          "type": "INT",
+          "widget": {
+            "name": "value"
+          },
+          "link": null
+        }
+      ],
+      "outputs": [
+        {
+          "localized_name": "INT",
+          "name": "INT",
+          "type": "INT",
+          "links": [
+            634
+          ]
+        }
+      ],
+      "properties": {
+        "cnr_id": "comfy-core",
+        "ver": "0.3.0",
+        "Node name for S&R": "PrimitiveInt"
+      },
+      "widgets_values": [
+        5,
+        "fixed"
+      ],
+      "title": "DURATION_SECONDS (max 10)"
+    },
+    {
+      "id": 341,
+      "type": "MarkdownNote",
+      "pos": [
+        -560,
+        480
+      ],
+      "size": [
+        340,
+        180
+      ],
+      "flags": {},
+      "order": 0,
+      "mode": 0,
+      "inputs": [],
+      "outputs": [],
+      "properties": {},
+      "title": "Duration note",
+      "widgets_values": [
+        "## Video length\nSet **DURATION_SECONDS** above (API: `--set 340.value=N`).\n\n**Ceiling: 10 s** \u2014 enforced by a clamp inside the subgraph. LTX 2.3 is trained for clips up to ~10 s; beyond that motion coherence and quality degrade.\n\nVRAM grows with length: fp8 ~67 GB at 8 s; **bf16 peaks ~75 GB at just 5 s** \u2014 use the fp8 workflow for 8-10 s clips.\n\nFrames = duration x fps + 1, snapped to the VAE temporal grid (so 5 s -> 4.84 s actual)."
+      ]
     }
   ],
   "links": [
@@ -355,6 +423,14 @@
       320,
       0,
       "IMAGE"
+    ],
+    [
+      634,
+      340,
+      0,
+      320,
+      5,
+      "INT"
     ]
   ],
   "groups": [],
@@ -2194,7 +2270,7 @@
                 "name": "INT",
                 "type": "INT",
                 "links": [
-                  628
+                  720
                 ]
               }
             ],
@@ -4003,6 +4079,61 @@
             "widgets_values": [
               "min(max(64*round(sqrt(c*d*b/a)/64), 384), 1792)"
             ]
+          },
+          {
+            "id": 333,
+            "type": "ComfyMathExpression",
+            "pos": [
+              1190,
+              4900
+            ],
+            "size": [
+              260,
+              60
+            ],
+            "flags": {},
+            "order": 0,
+            "mode": 0,
+            "inputs": [
+              {
+                "label": "a",
+                "localized_name": "values.a",
+                "name": "values.a",
+                "type": "FLOAT,INT,BOOLEAN",
+                "link": 720
+              }
+            ],
+            "outputs": [
+              {
+                "localized_name": "FLOAT",
+                "name": "FLOAT",
+                "type": "FLOAT",
+                "links": null
+              },
+              {
+                "localized_name": "INT",
+                "name": "INT",
+                "type": "INT",
+                "links": [
+                  628
+                ]
+              },
+              {
+                "localized_name": "BOOL",
+                "name": "BOOL",
+                "type": "BOOLEAN",
+                "links": null
+              }
+            ],
+            "properties": {
+              "cnr_id": "comfy-core",
+              "ver": "0.3.0",
+              "Node name for S&R": "ComfyMathExpression"
+            },
+            "widgets_values": [
+              "min(max(a, 1), 10)"
+            ],
+            "title": "duration ceiling: 10 s max"
           }
         ],
         "groups": [
@@ -4714,8 +4845,8 @@
           },
           {
             "id": 628,
-            "origin_id": 301,
-            "origin_slot": 0,
+            "origin_id": 333,
+            "origin_slot": 1,
             "target_id": 323,
             "target_slot": 0,
             "type": "INT"
@@ -4919,6 +5050,14 @@
             "target_id": 332,
             "target_slot": 3,
             "type": "INT"
+          },
+          {
+            "id": 720,
+            "origin_id": 301,
+            "origin_slot": 0,
+            "target_id": 333,
+            "target_slot": 0,
+            "type": "INT"
           }
         ],
         "extra": {