Predicting Where Not to Place Anchor Frames in Pose-Guided Human Video Generation
Abstract
Pose-guided human image animation recreates the motion of a reference video with a new subject appearance, conditioned on a driving pose sequence and a small budget of appearance reference frames, which we call anchors. Each anchor is assigned to a specific timestamp, where the video generator must match that frame; it then synthesizes the full clip subject to both these timestamped anchors and the pose sequence. Each anchor costs one image-model call, so their number is budgeted. The video generator is far more expensive, at a real-time factor of about 4.5 (30 fps at 960×512 on one B200 GPU). Selecting anchor positions is important: placing anchors in the low-error regions of a clip's pose-error profile (error between reference and generated video) increases the mean error by 8.6% relative to uniform placement, with larger penalties on harder-motion datasets. Identifying those regions by measurement costs two video-generation calls. We instead predict the per-frame error profile before video generation with a 254k-parameter head on the generator's 319M frozen VAE encoder. On unseen, out-of-distribution videos it attains a Spearman correlation of 0.638. The frames it selects as lowest-error sit at the 18th percentile of realised error, against the 14th when selecting on the measured profile. The ranking transfers without retraining to AIST++ and HyperMotionX. An agentic planner can use the prediction before any generation. Distributing a fixed anchor budget across clips by predicted difficulty captures a median 79% (IQR 56–87% across budget levels) of an oracle allocator's gain.