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  Compressed multimedia data streams transmitted over error prone channels, such as wireless networks and internet, are usually corrupted by channel errors. MPEG-4, which is one of the ISO visual coding standards, offers some optional error resilience tools, such as Video Packets (VPs) and Data Partitioning, to minimize the damages caused by bit-stream errors. But despite these techniques, corruptions are still likely to degrade the visual quality of the decoded streams. Therefore, some efficient error concealment techniques are needed on the decoder side to mask such impairments and ensure the consumer acceptance of MPEG-4 devices. Amongst them, temporal concealment techniques are important, which exploit temporal redundancy to conceal transmission errors. The existing temporal methods only interpolate one motion vector (MV) per macroblock (MB). But in MPEG-4 some special inter modes are introduced, such as inter4v. Inter4v mode encodes four MVs per MB. It performs motion estimation for 8×8 block to get more refined motion compensation, which is valid in violet motion image. Only recover one MV for the corrupted inter4v MB may not be sufficient to conceal it. Concerning inter4v mode employed widely, we proposed an improved algorithm to give more accurate estimation for corrupted motion vectors. Firstly, we judge whether the missing MB is inter4v one or not by its neighborhood. Then to inter4v missing MB, we recover its four MV and the damaged MB is reconstructed by performing motion compensation respectively to each 8×8 block. If the missing MB is not inter4v mode, it is concealed by using the average motion vector method or 0 MV if there are no reconstructed surrounding ones as its estimated MV. Performance of the schemes for various BLR (Block Loss Ratio) is compared with the existing schemes. Experimental results show that the proposed method significantly outperforms some existing methods and have a lower computational complexity. It is suited for low complexity video real-time implementations.……