Video Error Concealment

A method of concealing an error in a video stream, the video stream comprising a current frame comprising a lost image region, and a reference frame, the method comprising using a motion vector to identify a reference image region in the reference frame;

• calculating a motion compensated temporal activity of an image region in the current frame based on a comparison between the image region in the current frame and the reference image region in the reference frame;
• selecting a spatial or temporal error concealment mode based on the calculated temporal activity;
• and concealing the lost image region using the selected error concealment mode.

A method of concealing an error in a video stream, the video stream comprising a current frame comprising a lost image region, and a reference frame, the method comprising forming a list of motion vector candidates, the list of motion vector candidates including a set of one or more motion vectors from the current frame and a set of one or more motion vectors from the reference frame;

• testing each of the motion vector candidates using a matching error measure;
• selecting a replacement motion vector from the list based on the matching error measures;
• and using the selected replacement motion vector to conceal the lost image region.