---
title: PhyFPS-Bench-Gen
description: "100-prompt chronometric audit: does Meta FPS match the PhyFPS implied by motion? All metrics lower-is-better. Not a physics-law bench."
---

PhyFPS-Bench-Gen (TACO Group, Texas A&M) audits **chronometric hallucination**: whether a generator's declared container frame rate (**Meta FPS**) matches the physical speed implied by the motion (**PhyFPS**, from Visual Chronometer). It is **not** a law, grounding, education, or continuation bench.

The suite is **100 prompts**. Name outputs `0001.mp4` … `0100.mp4`. The predictor runs on sliding windows (`--stride`, `--clip-length`); the scorecard reports Meta-vs-PhyFPS error plus intra- and inter-video coefficients of variation. **Every metric is lower-is-better.**

Code: [taco-group/Visual_Chronometer](https://github.com/taco-group/Visual_Chronometer). Checkpoint: [xiangbog/Visual_Chronometer](https://huggingface.co/xiangbog/Visual_Chronometer) (`vc_common_10_60fps.ckpt`).

WorldFoundry runs Visual Chronometer `predict.py` in tree and/or normalizes a caller `results.csv`. Alignment metrics need `WORLDFOUNDRY_PHYFPS_META_FPS` (or a manifest).

<BenchmarkPageSections id="phyfps-bench-gen" locale="en" />

## How to run

Import an existing `results.csv`:

```bash
worldfoundry-eval zoo benchmark-run \
  --benchmark-id phyfps-bench-gen \
  --mode official-validation \
  --official-results-path <results.csv> \
  --generated-artifact-dir <generated_videos> \
  --output-dir tmp/phyfps-bench-gen/official-validation \
  --json
```

Predict PhyFPS in tree (needs the VC-Common checkpoint and Meta FPS for alignment):

```bash
export WORLDFOUNDRY_PHYFPS_META_FPS=24
${WORLDFOUNDRY_UNIFIED_PYTHON} \
  worldfoundry/evaluation/tasks/execution/runners/phyfps_bench_gen/run_phyfps_bench_gen_official_runner.py \
  --run-official \
  --generated-artifact-dir "${WORLDFOUNDRY_GENERATED_ARTIFACT_DIR}" \
  --stride 4 \
  --output-dir tmp/phyfps_bench_gen/official \
  --json
```

Outputs include `scorecard.json` (primary `phyfps_bench_gen_average`) and `results.csv`.

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