the error concealment feature feature in the H.26L test model

ABSTRACT

The paper presnets the error concealment feature in the earliest standard of 26L, and it was adopted and included in TML-9.0.

EC STRATEGY

The erroneous slices are discarded.
A record is kept in a MB based status map of the frame. the status of MB is "Correctly received" or "Lost".
First decode the received slices, then decode the "Lost".
"Concealed" can be used as reliable neighbors in the concealment process when there are not "Correctly received"
The order is important for concealment mistake.

THE SELECTED EC ALGORITHMS

INTRA Frame Concealment

Based on weighted pixel averaging.

INTER Frame Concealment

If the average MV is smaller than a pre-defined threshold, the lost slices are concealed by copying from the spatially corresponding positions in the reference frame.
Else predict from a apatial neighbor MB's motion(from one! it was found in the experiments). the decision of which MV to use as prediction the current MB is made based on minimizing the side match distortion .

ADDITIONAL IMPLEMENTATION ISSUES

Multiple reference frames
Entire frame losses
B-frame concealment