Metric	Input	Interpretation
`FID_k`	72D kinetic clip features	Lower is better
`FID_g`	32D geometric clip features	Lower is better
`Diversity_k`	Pairwise distance in normalized kinetic space	Compare with GT
`Diversity_g`	Pairwise distance in normalized geometric space	Compare with GT
`BeatAlign`	Music beats to local minima of mean joint speed	Higher is better
`FID_uTMR`	L2-normalized universal-TMR motion embeddings	Lower is better

Generated clips are first-root anchored and cropped to 1,200 frames. Kinetic and geometric reference features are extracted from each complete AIST++ v1 sequence without cropping. Both sides are normalized with the complete GT feature-pool statistics before FID and Diversity are computed. Beat alignment uses the complete generated clip. The public Bailando path uses 60 fps data; Motius defines its smoothing and alignment kernels in seconds (83.3 ms and 50 ms), making the same formula valid for the repository's 30 fps motion data.

FID_uTMR first selects the common SMPL-22 body, resamples to 30 fps, canonicalizes the clip to first-frame +Z facing, and caps it at 20 seconds. The universal joint-position evaluator encodes joints66 and every embedding is L2-normalized before FID is computed against the 1,320-motion AIST++ pool.

The feature extractors are the Bailando/Fairmotion implementations vendored under motius.evaluation.metrics.dance_features. They have no learned checkpoint. The evaluator additionally reports checkpoint-free Motius physical diagnostics on joints 0:22; these diagnostics are not part of the CVPR paper table.

Python API

python

from motius.evaluation import AISTPPMusicDanceEvaluator

evaluator = AISTPPMusicDanceEvaluator.from_pretrained(
    "ZeyuLing/Motius-Evaluator-AISTPP-Music-to-Dance",
    joint_fid=True,
    device="cuda",
)
evaluator.process(
    {
        "name": sequence_id,
        "pred_joints": generated_smpl24,
        "gt_joints": paired_gt_smpl24,
        "music_beats": full_rate_music_features[:, 53].astype(bool),
        "music_fps": 60.0,
        "motion_fps": 60.0,
    }
)
metrics = evaluator.compute()

Set the actual source frame rates on every sample. Native AIST++/Bailando data uses 60 fps motion and beat features; standardized Motius datasets commonly use 30 fps motion. The evaluator converts beat locations through time and does not assume these rates are equal.

BeatAlign Audit

On all 40 released Bailando predictions, Motius at 60 fps produces 0.2268095553; the maximum per-case difference from the upstream Bailando implementation is 2.3e-15. Resampling the same predictions to 30 fps under the time-defined protocol gives 0.2270610403. The gap to the paper's 0.2332 is therefore not caused by frame-rate handling or a reimplementation error. The public GT package shows the same snapshot mismatch (0.2247 from released code/data versus 0.2374 reported in the paper).

Reference Pool Audit

The AIST++ v1 metadata declares 1,408 sequences, while the released motion archive contains 1,365 SMPL PKLs. Applying the official 45-entry ignore list leaves 1,320 valid motions, all of which are recorded by name in the protocol artifact. The original Google Storage link expired in 2026 and its replacement GitHub motions.zip currently contains only 411 motions. Motius therefore rebuilds the complete pool from the preserved public archive mirror at yeok/danceba, revision 637d0aadf69e3e926ba70bfee9ff89571fd18813. A sample of 86 overlapping motion files matches the current official GitHub release byte for byte. Source names, skipped entries, hashes, and the calibrated SMPL-24 skeleton report are shipped with the evaluator artifact.

The converted official checkpoints reproduce the paper table on all 40 cross-modal evaluation cases:

Row	FID_k	FID_g	uTMR FID	Diversity_k	Diversity_g	BeatAlign
Motius GT	17.16	10.66	0.1829	8.17	7.49	0.2247
GT paper	17.10	10.60	-	8.19	7.45	0.2374
Motius Bailando	28.11	9.70	0.3138	7.73	6.31	0.2268
Bailando paper	28.16	9.62	-	7.83	6.34	0.2332

The Motius rows are computed outputs; the paper rows are parity targets and are not hard-coded by the evaluator.

Provenance

The implementation follows lisiyao21/Bailando revision cc90b98bff81c9709570db413c9610c2562e27ca. Bailando is distributed under the S-Lab License 1.0; the kinetic/geometric files retain Fairmotion BSD headers.