Open-weight alternatives for upscaling AI video (SeedVR2, FlashVSR+) run in ComfyUI on a 24 GB GPU; generative upscalers trade fidelity for perceived sharpness, so check faces/text after upscaling

Self-hosted counterpart to commercial finishing tools (C3-B479-01). SeedVR2 (ByteDance Seed): 3B and 7B weights on Hugging Face under apache-2.0; Comfy-Org hosts a repackaged set in fp16, fp8, int8, mxfp8 and nvfp4 precisions (652k downloads) and the community numz ComfyUI wrapper has ~2.9k stars (R1, R5). FlashVSR+ (13 Oct 2026, R2): hybrid local/sparse-global attention gives up to 2x DiT speed and 45% lower peak memory, "enabling spatially untiled 4K VSR on a single 24GB RTX 4090", with reward-weighted distillation for user-preferred one-step output; code, models and training data released (code Apache-2.0; ComfyUI wrappers exist, one GPL-3.0) (R2, R4). A zero-shot pipeline from pretrained parts reaches ~32 fps at 720p on one RTX 4090 but explicitly trades "reconstruction fidelity for strong no-reference perceptual quality" and struggles with hard motion (R3). Practical: (1) a 24 GB card can now upscale generated clips to 4K locally without tiling seams; (2) generative VSR invents plausible detail - fine for stylised or background plates, risky for faces, on-screen text, logos and likeness-sensitive shots, where recognition-oriented evaluation (FANVIDv2 scores whether faces/plates remain identifiable, R6) is a better check than sharpness; (3) check weight licences separately from wrapper code licences (GPL wrappers impose obligations if redistributed). Curator qualifications: All cited documentation excerpts located on the live pages by curator GET; no video sources. Abstract-level reading of the paper(s); full methods not read by discovery or the curator. FlashVSR+ weight licence not confirmed. Not installed or run (no source execution). Limitations: Abstract-level reading only; no benchmarks compared across SeedVR2/FlashVSR+/Topaz; FlashVSR+ weight licence not confirmed (only code licence); speed figures are authors' on RTX 4090; no source executed. R3 code not yet released. Evidence status: statements located in the cited sources by a correlated desk review (Claude); not executed; not independently reviewed.

{
  "citations": [
    {
      "url": "https://arxiv.org/abs/2610.17552",
      "note": "abstract; abstract; ByteDance-Seed/SeedVR2-7B card metadata"
    },
    {
      "url": "https://arxiv.org/abs/2610.13179",
      "note": "abstract; abstract; ByteDance-Seed/SeedVR2-7B card metadata"
    },
    {
      "url": "https://huggingface.co/api/models?search=SeedVR&sort=downloads",
      "note": "abstract; abstract; ByteDance-Seed/SeedVR2-7B card metadata"
    }
  ]
}