Update Wan 2.1 I2V base model to use 720P resolution variant

When selecting a Wan 2.1 I2V model that is a LoRA or tensor weight,
the base model now uses Wan-AI/Wan2.1-I2V-14B-720P-Diffusers instead
of the generic Wan-AI/Wan2.1-I2V-14B-Diffusers.

videogen.py

@@ -1902,7 +1902,7 @@ def add_model_from_hf(model_id_or_url, name=None, hf_token=None, debug=False):
                     base_model = "Wan-AI/Wan2.2-I2V-A14B-Diffusers" if is_i2v else "Wan-AI/Wan2.2-T2V-A14B-Diffusers"
                 else:
                     # Wan 2.1 and earlier
-                    base_model = "Wan-AI/Wan2.1-I2V-14B-Diffusers" if is_i2v else "Wan-AI/Wan2.1-T2V-14B-Diffusers"
+                    base_model = "Wan-AI/Wan2.1-I2V-14B-720P-Diffusers" if is_i2v else "Wan-AI/Wan2.1-T2V-14B-Diffusers"
             elif "svd" in model_id.lower() or "stable-video" in model_id.lower():
                 base_model = "stabilityai/stable-video-diffusion-img2vid-xt-1-1"
             elif "flux" in model_id.lower():
@@ -2712,7 +2712,7 @@ def update_all_models(hf_token=None):
                         base_model = "Wan-AI/Wan2.2-I2V-A14B-Diffusers" if m["is_i2v"] else "Wan-AI/Wan2.2-T2V-A14B-Diffusers"
                     else:
                         # Wan 2.1 and earlier
-                        base_model = "Wan-AI/Wan2.1-I2V-14B-Diffusers" if m["is_i2v"] else "Wan-AI/Wan2.1-T2V-14B-Diffusers"
+                        base_model = "Wan-AI/Wan2.1-I2V-14B-720P-Diffusers" if m["is_i2v"] else "Wan-AI/Wan2.1-T2V-14B-Diffusers"
                 elif "svd" in model_id.lower() or "stable-video" in model_id.lower():
                     base_model = "stabilityai/stable-video-diffusion-img2vid-xt-1-1"
                 elif "flux" in model_id.lower():
@@ -2818,7 +2818,7 @@ def update_all_models(hf_token=None):
                         base_model = "Wan-AI/Wan2.2-I2V-A14B-Diffusers" if m["is_i2v"] else "Wan-AI/Wan2.2-T2V-A14B-Diffusers"
                     else:
                         # Wan 2.1 and earlier
-                        base_model = "Wan-AI/Wan2.1-I2V-14B-Diffusers" if m["is_i2v"] else "Wan-AI/Wan2.1-T2V-14B-Diffusers"
+                        base_model = "Wan-AI/Wan2.1-I2V-14B-720P-Diffusers" if m["is_i2v"] else "Wan-AI/Wan2.1-T2V-14B-Diffusers"
                 elif "svd" in model_id.lower() or "stable-video" in model_id.lower():
                     base_model = "stabilityai/stable-video-diffusion-img2vid-xt-1-1"
                 elif "flux" in model_id.lower():
@@ -4442,7 +4442,7 @@ def select_best_model(gen_type, models, vram_gb=24, prefer_quality=True, return_
                         base_model_id = "Wan-AI/Wan2.2-I2V-A14B-Diffusers" if "i2v" in lora_id else "Wan-AI/Wan2.2-T2V-A14B-Diffusers"
                     else:
                         # Wan 2.1 and earlier
-                        base_model_id = "Wan-AI/Wan2.1-I2V-14B-Diffusers" if "i2v" in lora_id else "Wan-AI/Wan2.1-T2V-14B-Diffusers"
+                        base_model_id = "Wan-AI/Wan2.1-I2V-14B-720P-Diffusers" if "i2v" in lora_id else "Wan-AI/Wan2.1-T2V-14B-Diffusers"
                 elif "svd" in lora_id or "stable-video" in lora_id:
                     base_model_id = "stabilityai/stable-video-diffusion-img2vid-xt-1-1"
                 elif "sdxl" in lora_id:
@@ -8677,7 +8677,7 @@ def main(args):
                 elif "wan2.1" in lora_id_lower or "wan2_1" in lora_id_lower:
                     # Wan 2.1 models - use lora_id_lower to determine I2V vs T2V
                     if "i2v" in lora_id_lower:
-                        base_model_id = "Wan-AI/Wan2.1-I2V-14B-Diffusers"
+                        base_model_id = "Wan-AI/Wan2.1-I2V-14B-720P-Diffusers"
                     else:
                         base_model_id = "Wan-AI/Wan2.1-T2V-14B-Diffusers"
                 else:
@@ -9847,8 +9847,8 @@ def main(args):
                             # Wan 2.2 generic - MUST come after specific I2V/T2V keys
                             "wan2.2": "Wan-AI/Wan2.2-T2V-A14B-Diffusers",
                             # Wan 2.1 I2V models - more specific keys FIRST
-                            "wan2.1.i2v.a14b": "Wan-AI/Wan2.1-I2V-14B-Diffusers",
-                            "wan2.1.i2v": "Wan-AI/Wan2.1-I2V-14B-Diffusers",
+                            "wan2.1.i2v.a14b": "Wan-AI/Wan2.1-I2V-14B-720P-Diffusers",
+                            "wan2.1.i2v": "Wan-AI/Wan2.1-I2V-14B-720P-Diffusers",
                             "wan2.1.t2v": "Wan-AI/Wan2.1-T2V-14B-Diffusers",
                             # Wan 2.1 generic - MUST come after specific I2V/T2V keys
                             "wan2.1": "Wan-AI/Wan2.1-T2V-14B-Diffusers",
@@ -10323,7 +10323,7 @@ List TTS voices:
     
     parser.add_argument("--base-model", type=str, default=None,
                         metavar="MODEL_ID",
-                        help="Override base model for LoRA adapters (e.g., Wan-AI/Wan2.1-I2V-14B-Diffusers)")
+                        help="Override base model for LoRA adapters (e.g., Wan-AI/Wan2.1-I2V-14B-720P-Diffusers)")
     parser.add_argument("--prompt", nargs="+", required=False)
     parser.add_argument("--image_to_video", action="store_true",
                         help="Enable image-to-video mode (use --image to provide an image, or --image_model to generate one)")