Struct TemporalSmoother 

pub struct TemporalSmoother { /* private fields */ }

Temporal smoother for rolling shutter motion vectors.

Applies an exponentially weighted moving average (EWMA) across consecutive frames to suppress frame-to-frame jitter in the per-scanline motion estimates. This is critical for preventing flickering artifacts that occur when raw per-frame motion vectors vary erratically.

Algorithm

For each block index i, the smoother maintains a running estimate:

mv_smoothed[i] = alpha * mv_new[i] + (1 - alpha) * mv_prev[i]

A lower alpha produces more temporal smoothing (more lag), while a higher alpha responds faster to genuine motion changes.

Implementations

impl TemporalSmoother

pub fn new(alpha: f64) -> Self

Create a new temporal smoother.

alpha is clamped to [0.01, 1.0].

pub fn smooth(&mut self, motion_vectors: &[MotionVector]) -> Vec<MotionVector>

Smooth a new frame’s motion vectors against the running average.

On the first call the input is returned as-is (there is no history). Subsequent calls blend the new vectors with the accumulated state.

If the number of blocks changes between calls (e.g. resolution change) the state is reset.

pub fn reset(&mut self)

Reset the internal state so the next call starts fresh.

pub fn alpha(&self) -> f64

Current smoothing factor.

pub fn num_blocks(&self) -> usize

Number of blocks tracked.