ACCV 2026 Accepted paper Paper ID 452

SAGA: Stable Acceleration Guidance for Autoregressive Video Generation

Thanh-Nhan Vo1,2 Trong-Thuan Nguyen1,2 Trung-Hoang Le1,2 Tam V. Nguyen3 Minh-Triet Tran1,2
1University of Science, VNU-HCM, Vietnam 2Vietnam National University, Ho Chi Minh City 3University of Dayton, Ohio, U.S.A.
vtnhan@selab.hcmus.edu.vn, {ntrthuan, lthoang}@hcmus.edu.vn, tnguyen1@udayton.edu, tmtriet@fit.hcmus.edu.vn

Interactive Stability Comparison

Watch the same prompt side by side to compare temporal stability.

Speed:
BaselineSelf-Forcing
SAGAOurs
0.00 / 0.00s
Text Prompt: Loading prompt...

+0.21%
Latency Overhead
Tested on NVIDIA RTX 5090
+0.008 GiB
Peak Memory
Practically zero memory footprint
62.7%
User Preference Win
Pairwise human evaluation victory
97.91
VBench Temporal Score
Consistent boost across backbones

How SAGA Works

Addressing spectral instability in autoregressive video diffusion through acceleration-domain kinematics and finite-support Slepian concentration.

Core Insight: Why Second-Order Acceleration?

Discrete latent acceleration $\mathbf{a}_t = \mathbf{z}_{t+1} - 2\mathbf{z}_t + \mathbf{z}_{t-1}$ corresponds to a high-pass frequency response $H(\omega) = 4\sin^2(\omega/2)$. While semantic motion and camera pans live in the low-frequency band ($\omega \to 0$), high-frequency temporal perturbations (jitter, flickering) are amplified up to 4× in power. Regulating acceleration directly exposes and eliminates these temporal errors without blurring spatial details.

Pillar 1: Inference Guidance

Acceleration-Domain Spectral Guidance (SG)

Because autoregressive rollout operates on short temporal chunks (sliding windows), standard Discrete Fourier Transforms (DFT) suffer from severe spectral leakage. SAGA adopts Discrete Prolate Spheroidal Sequences (DPSS / Slepian basis), which provably maximize energy concentration in finite temporal intervals. By projecting latent acceleration onto band-limited Slepian vectors, SAGA isolates and penalizes high-frequency kinematic energy during reverse denoising.

$$\mathcal{E}_{\text{kin}}(\hat{\mathbf{z}}_0) = \sum_{k=K_c}^{N-1} \|\beta_k\|^2, \quad \beta_k = \mathbf{v}_k^T \mathbf{a}_t$$
Pillar 2: Stochastic Prior

Structured Autoregressive Noise (SAN)

SAN combines two independent, variance-preserving AR(1) streams with opposite temporal correlations. When $\theta=\pi/4$ and $\rho_{\mathrm{lf}}=-\rho_{\mathrm{hf}}=\rho$, the combined noise has zero adjacent-frame correlation, $R(1)=0$, while retaining higher-lag correlation, $R(2)=\rho^2$. Each frame remains marginally standard Gaussian.

$$\begin{aligned}\mathbf{z}_t &= \cos\theta\,\mathbf{z}^{\mathrm{lf}}_t + \sin\theta\,\mathbf{z}^{\mathrm{hf}}_t,\\ \mathbf{z}^{\mathrm{type}}_t &= \rho_{\mathrm{type}}\mathbf{z}^{\mathrm{type}}_{t-1} + \sqrt{1-\rho_{\mathrm{type}}^2}\,\boldsymbol{\epsilon}^{\mathrm{type}}_t.\end{aligned}$$
SAGA Pipeline Workflow Click to Zoom
Figure 1: End-to-end SAGA workflow for autoregressive video generation. A frozen causal DiT rolls out latent chunks using SG (Spectral Guidance) and SAN (Structured AR Noise), subsequently decoding the stabilized trajectory $\mathbf{z}_{1:T}$ via a standard VAE decoder into high-fidelity video.
SAGA Detailed Architecture Click to Zoom
Figure 2: Detailed architectural mechanisms of SAGA. (Top) Structured frequency-aware noise initialization establishing a neutral motion prior; (Bottom) Inference-time spectral guidance computing high-frequency kinematic energy over discrete acceleration and guiding the denoising trajectory through Slepian projections.

Quantitative Benchmarks

Extensive benchmarking on the VBench suite and human preference studies demonstrate consistent improvements across backbones.

Model Backbone Params Subject (SC) Background (BC) Flickering (TF) Smoothness (MS) Temporal (TQ) Aesthetic (AQ) Image (IQ)
Autoregressive-Diffusion Hybrid Baselines
CausVid (CVPR 2025) 1.3B 95.91 96.46 99.02 97.81 97.30 64.18 67.23
Self-Forcing (NeurIPS 2025) 1.3B 95.60 96.20 99.00 98.38 97.30 66.33 69.60
Causal-Forcing (ICML 2026) 1.3B 95.43 96.15 97.97 97.52 96.77 66.82 70.11
Our Stabilized Backbones (+ SAGA)
CausVid + SAGA 1.3B 96.71 96.59 98.96 98.04 97.58 64.39 67.46
Self-Forcing + SAGA 1.3B 96.63 96.95 99.19 98.85 97.91 66.48 70.51
Causal-Forcing + SAGA 1.3B 96.13 96.57 98.63 97.97 97.33 66.66 69.83
SC: Subject Consistency BC: Background Consistency TF: Temporal Flickering MS: Motion Smoothness TQ: Temporal Quality AQ: Aesthetic Quality IQ: Image Quality

Temporal Consistency vs. Rollout Horizon

SAGA maintains superior stability over long-horizon rollouts up to 30 seconds, preventing error accumulation.

Temporal quality scores for SAGA and Self-Forcing at 5, 10, and 30 seconds Zoom

All Pairwise Outcomes (Including Ties)

Comprehensive evaluation outcomes including ties (video-level: 58% SAGA vs. 34% baseline).

Video level
Per vote

Negligible Inference Overhead

Because SAGA operates exclusively via closed-form Slepian linear projections and lightweight kinematic loss during denoising, it adds virtually zero computational penalty to the base generative model.

+0.21%
Latency Overhead
+8.2 MB
VRAM Footprint
0
Retraining Needed

BibTeX

If you find SAGA useful in your research, please cite our ACCV 2026 paper.

citation.bib
@inproceedings{vo2026saga,
  title     = {SAGA: Stable Acceleration Guidance for Autoregressive Video Generation},
  author    = {Vo, Thanh-Nhan and Nguyen, Trong-Thuan and Le, Trung-Hoang and Nguyen, Tam V. and Tran, Minh-Triet},
  booktitle = {Asian Conference on Computer Vision (ACCV)},
  year      = {2026}
}