Reconstructing lost video data in a lapped orthogonal transform based coder

Techniques for hiding defects caused by lost blocks of lapped orthogonal transform (LOT) coefficients are proposed and compared. By properly enhancing reconstructed blocks, a video system can transmit pleasing images in spite of frequent asynchronous transfer mode (ATM) network losses. The mathematics of LOT calculation suggest several reconstruction strategies. Standard signal-processing techniques such as mean-square-error minimization, time-domain filtering, and LOT-domain coefficient averaging are also investigated and simulated. Comments on the performance of these recovery methods for moving video sequences as well as for single frames are offered. >