Detection code to make ltxv models without config work. (Comfy-Org#7986)

Author: comfyanonymous

comfy/model_detection.py

@@ -222,6 +222,10 @@ def detect_unet_config(state_dict, key_prefix, metadata=None):
     if '{}adaln_single.emb.timestep_embedder.linear_1.bias'.format(key_prefix) in state_dict_keys: #Lightricks ltxv
         dit_config = {}
         dit_config["image_model"] = "ltxv"
+        dit_config["num_layers"] = count_blocks(state_dict_keys, '{}transformer_blocks.'.format(key_prefix) + '{}.')
+        shape = state_dict['{}transformer_blocks.0.attn2.to_k.weight'.format(key_prefix)].shape
+        dit_config["attention_head_dim"] = shape[0] // 32
+        dit_config["cross_attention_dim"] = shape[1]
         if metadata is not None and "config" in metadata:
             dit_config.update(json.loads(metadata["config"]).get("transformer", {}))
         return dit_config