Enhanced the comfyui savevideo node to support previewing and saving videos containing alpha channels.

1. Download models

• The Wan DiT base model: wan2.1_t2v_14B_fp16.safetensors
• The Wan text encoder: umt5_xxl_fp8_e4m3fn_scaled.safetensors
• The LightX2V model: lightx2v_T2V_14B_cfg_step_distill_v2_lora_rank64_bf16.safetensors
• RGBA Dora: epoch-13-1500_changed.safetensors
• RGB VAE Decoder: wan_alpha_2.1_vae_rgb_channel.safetensors.safetensors
• Alpha VAE Decoder: wan_alpha_2.1_vae_alpha_channel.safetensors.safetensors

2. Copy the files into the ComfyUI/models folder and organize them as follows:

ComfyUI/models
├── diffusion_models
│   └── wan2.1_t2v_14B_fp16.safetensors
├── loras
│   ├── epoch-13-1500_changed.safetensors
│   └── lightx2v_T2V_14B_cfg_step_distill_v2_lora_rank64_bf16.safetensors
├── text_encoders
│   └── umt5_xxl_fp8_e4m3fn_scaled.safetensors
├── vae
│   ├── wan_alpha_2.1_vae_alpha_channel.safetensors.safetensors
│   └── wan_alpha_2.1_vae_rgb_channel.safetensors.safetensors

3. Copy this repo or SaveVideoRGBA.py into the ComfyUI/custom_nodes folder.

• Wan-Alpha for the alpha video generate
• ComfyUI for the node workflow framework