Video-PiD: Pixel-Space Decoder for Wan 2.1

A small 3D pixel-space diffusion model that runs on top of Wan 2.1's VAE-decoded video frames to fix the "plastic" / waxy look of latent diffusion decoders.

Status: pre-alpha. No weights yet. This repo will hold the trained checkpoints. The source code lives at github.com/madxmoron/video-pid.

  Wan 2.1 1.3B T2V                          Video-PiD
  ┌──────────┐    Wan-VAE      ┌──────────┐    residual    ┌──────────┐
  │ text     │──▶ decode ─────▶│ pixel    │──▶ denoise ──▶│ pixel    │──▶ video
  │ latent   │    (plastic)    │ frames   │   (4 steps)   │ frames   │   (sharp)
  └──────────┘                 └──────────┘                └──────────┘

Why

Latent diffusion decoders (Wan-VAE, SD-VAE, etc.) throw away high-frequency detail and re-introduce a "waxy" smoothness. Video-PiD is a tiny post-pass that re-denoises the decoded frames in pixel space, conditioning on the original latent, and outputs a residual that adds back the detail.

Inspired by NVIDIA's PiD (image-only). We extend it to video, in 3D, as a plug-in for Wan 2.1.

Roadmap

• Architecture spec pinned (in progress)
• Training run on Panda-70M / HD-VGGT
• First checkpoint release (v0.1.0)
• ComfyUI node

See github.com/madxmoron/video-pid/blob/main/docs/ROADMAP.md for the full plan.

License

Apache 2.0.

Citation

@software{video_pid_2026,
  author = {madxmoron},
  title = {Video-PiD: Pixel-Space Decoder for Wan 2.1},
  year = {2026},
  url = {https://github.com/madxmoron/video-pid}
}