video_hand_motion_smooth_mapper¶

Apply smoothing to world-space hand motions and remove outliers.

Reads hand action results (states, actions, joints_world) produced by VideoHandActionComputeMapper and applies:

Extreme outlier replacement — frames whose instantaneous wrist speed exceeds median + outlier_velocity_threshold * MAD are replaced by linear interpolation from neighbors (not deleted).
Savitzky-Golay smoothing — positions are smoothed with a Savitzky-Golay filter that preserves motion peaks while removing high-frequency jitter.
Quaternion smoothing — orientations are smoothed in quaternion space to avoid gimbal lock and discontinuities.
Action recomputation — 7-DoF actions are re-derived from the smoothed states so they stay consistent.

Reference (paper §3.1): “we apply spline smoothing to the world-space hand motions and remove outliers”

对世界坐标系下的手部运动应用平滑处理并剔除异常值。

读取由 VideoHandActionComputeMapper 生成的手部动作结果（states、actions、joints_world）并应用以下处理：

极端异常值替换 — 瞬时手腕速度超过 median + outlier_velocity_threshold * MAD 的帧，将通过相邻帧的线性插值进行替换（而非删除）。
Savitzky-Golay 平滑 — 使用 Savitzky-Golay 滤波器对位置进行平滑处理，在保留运动峰值的同时消除高频抖动。
四元数平滑 — 在四元数空间中对方向进行平滑处理，以避免万向节死锁和不连续性。
动作重新计算 — 从平滑后的状态重新推导 7 自由度动作，以保持一致性。

参考文献（论文 §3.1）： “我们对世界坐标系下的手部运动应用样条平滑并剔除异常值”

Type 算子类型: mapper

Tags 标签: cpu, video

🔧 Parameter Configuration 参数配置¶

name 参数名	type 类型	default 默认值	desc 说明
`hand_action_field`	<class ‘str’>	`'hand_action_tags'`	Meta field storing hand action results (output of VideoHandActionComputeMapper).
`savgol_window`	<class ‘int’>	`11`	Window length for Savitzky-Golay filter. Must be odd. Larger = smoother but may lose fast motions.
`savgol_polyorder`	<class ‘int’>	`3`	Polynomial order for Savitzky-Golay filter. Must be less than savgol_window.
`outlier_velocity_threshold`	<class ‘float’>	`5.0`	Frames whose wrist speed exceeds `median + threshold * MAD` are replaced by interpolation. Higher = more conservative (fewer replacements).
`min_frames_for_smoothing`	<class ‘int’>	`5`	Minimum number of valid frames required to apply smoothing.
`smooth_joints`	<class ‘bool’>	`True`	Whether to also smooth `joints_world` (21-joint MANO skeleton in world space).
`args`		``
`kwargs`		``