ICLR 2025 Procedure planning from visual endpoints

Masked Temporal Interpolation Diffusion for Procedure Planning in Instructional Videos

MTID learns latent visual mid-state guidance between a start and goal observation, then conditions a diffusion planner to predict the intervening discrete action sequence.

Yufan Zhou1 Zhaobo Qi1,* Lingshuai Lin1 Junqi Jing1 Tingting Chai1 Beichen Zhang1 Shuhui Wang2 Weigang Zhang1,*
1 Harbin Institute of Technology, Weihai 2 Key Laboratory of Intelligent Information Processing, Institute of Computing Technology, Chinese Academy of Sciences * Corresponding authors

Model output: dataset-defined action labels, not generated video frames. No annotated intermediate visual states are required.

MTID overview with endpoint task prediction, latent temporal interpolation, masked action-noise initialization, and temporal U-Net denoising. Open full resolution
MTID overview. Endpoint observations condition task prediction and latent interpolation. The task mask restricts action-noise initialization before DDIM denoising predicts the full sequence.

Problem & insight

Reasoning through what the camera never shows.

Procedure planning must infer the discrete actions connecting a visual start state Vs to a goal state Vg, even though every state in between is unobserved.

01 · Prior supervision

Useful semantics, limited visual detail

Earlier approaches often construct intermediate guidance from task labels, events, graphs, or language. These signals help identify what should happen, but describe less of the visual evolution between the endpoints.

02 · MTID

Visual-level guidance in latent space

MTID generates learnable latent features between the encoded endpoints, refines their temporal dependencies, and injects them directly into the action planner through cross-attention.

Latent mid-state guidance

Intermediate features are learned from the two observed endpoints without synthesizing pixels.

Task-aware initialization

The predicted task restricts initial action noise to the associated action vocabulary.

Endpoint-aware objective

A weighted masked loss emphasizes actions near the observed states and discourages irrelevant predictions.

Method

Three modules. Two training stages.

The task classifier is trained first. The latent interpolation module and diffusion planner are then optimized together, so the generated guidance adapts to action reasoning.

  1. Task prediction

    Identify the task from both endpoints.

    A Transformer classifier predicts the task from the start and goal observations. The class conditions planning and defines the task-specific action mask.

  2. Latent temporal interpolation

    Construct visual guidance between states.

    An observation encoder maps the endpoints to Ls and Lg. Learnable interpolation weights generate intermediate features, which Transformer blocks refine.

    Ij = (1 − φj)Ls + φjLg

  3. Masked diffusion planning

    Restrict first, then denoise jointly.

    The task mask is applied to the initial action noise—not at every denoising iteration. DDIM then denoises all T action steps jointly in a temporal U-Net.

Architecture details See how interpolation and cross-attention connect
Latent temporal interpolation module with endpoint encoding, learnable interpolation weights, and Transformer refinement. Open full resolution
Latent temporal interpolation. Encoded endpoints are mixed with learnable weights and refined into F1:M.
Residual temporal block fusing a timestep embedding and refined latent feature through cross-attention. Open full resolution
Cross-attention injection. Refined latent features condition residual temporal blocks throughout the U-Net.

Selected results

Strong where the comparison is direct.

Values are percentage points. CrossTask uses HowTo100M features under the PDPP setting for the dagger-marked rows in the paper’s main table.

CrossTask · T=3 · SR

40.45 +1.52 over SCHEMA in Table 1

CrossTask · T=3 · mAcc

67.19 +2.45 over KEPP in Table 1

CrossTask · main table

3 best SR results across T=3–5

CrossTask

Success Rate across horizons

Higher is better
CrossTask Success Rate comparison across prediction horizons
Method T=3 T=4 T=5 T=6
PDPP37.2021.4813.458.41
KEPP38.1224.1514.209.27
SCHEMA38.9324.5014.7510.53
MTID40.4524.7615.2610.30

MTID leads at T=3–5. At T=6, SCHEMA reports 10.53 versus MTID’s 10.30.

COIN & NIV · KEPP setting

Best SR and mAcc at T=4

COIN 180 tasks

22.74 SR

49.90 mAcc

NIV 5 tasks

24.89 SR

44.54 mAcc

mIoU is reported in the paper for completeness, but MTID is not the leading method on mIoU in these tables; this page therefore avoids an across-the-board state-of-the-art claim.

Same-setting gain over PDPP · CrossTask T=3

+3.25 SR

Same-setting gain over PDPP · CrossTask T=3

+2.52 mAcc

Same-setting gain over PDPP · CrossTask T=3

+2.60 mIoU

Ablations

Three questions, tested separately.

The experiments isolate what to interpolate, when to apply the task mask, and how to weight the objective. They are not presented as one cumulative ladder.

01

Interpolation design · T=3

Every module contributes

Interpolation only
37.86 SR
+ Observation encoder
39.23 SR
+ Transformer refinement
39.49 SR
Full stack
40.45 SR
02

Mask placement · T=3

Initialize once—do not clamp every step

No masked projection
39.17 SR
Mask at initialization
40.45 SR
Mask every iteration
3.38 SR
03

Training objective · T=5

Endpoint weighting drives the gain

MSE
11.89 SR
+ Gradient weighting
15.10 SR
+ Task mask
15.26 SR

Benchmarks & scope

Evaluated across three instructional-video datasets.

CrossTask2,750videos
  • 18 tasks
  • 105 action labels
  • 7.6 average actions per video
COIN11,827videos
  • 180 tasks
  • 778 step types
  • 3.6 average actions per video
NIV150videos
  • 5 tasks
  • 9.5 average actions per video
  • Longer instructional sequences

Evaluation protocol

Per-task 70 / 30 split

Videos are randomly split into 70% training and 30% testing within each task. Results measure in-distribution procedure planning rather than unseen-task generalization.

Known dependency

Task errors can propagate

Planning depends on the predicted task and dataset-specific action vocabulary. A task-class mismatch can therefore affect both conditioning and the action mask.

Output boundary

Action labels, not robot control

MTID predicts discrete benchmark actions from endpoint features. It is not a video-generation model, deployed robot policy, or real-time control system.

Citation

Build on MTID.

If this work supports your research, please cite the ICLR 2025 paper.

BibTeX
@inproceedings{zhou2025masked,
  title     = {Masked Temporal Interpolation Diffusion for Procedure Planning in Instructional Videos},
  author    = {Yufan Zhou and Zhaobo Qi and Lingshuai Lin and Junqi Jing and Tingting Chai and Beichen Zhang and Shuhui Wang and Weigang Zhang},
  booktitle = {The Thirteenth International Conference on Learning Representations},
  year      = {2025},
  url       = {https://openreview.net/forum?id=HnpDHiItd2}
}