1. A method comprising: determining, by a computing device, a per-tile motion estimate between a first m×n pixel tile from a first captured image of a scene and a second m×n pixel tile from a second captured image of the scene, wherein the per-tile motion estimate represents movement of the first m×n pixel tile to approximate the second m×n pixel tile; based on the approximation of the first m×n pixel tile to the second m×n pixel tile, estimating a per-tile confidence of the per-tile motion estimate; upsampling the per-tile motion estimate and the per-tile confidence to obtain respective per-pixel motion estimates and associated per-pixel confidences for pixels of the first m×n pixel tile; and iteratively filtering, by the computing device, the respective per-pixel motion estimates and associated per-pixel confidences, wherein the iterative filtering involves multiplying the respective per-pixel motion estimates and associated per-pixel confidences by an affinity matrix, and wherein the iterative filtering smoothes the respective per-pixel motion estimates and associated per-pixel confidences.