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Abstract
Nowadays audio-visual and multi media services are seen as important sources of the traffic within mobile networks. An important characteristic of such networks is that they cannot provide a guaranteed quality of service (QoS) due to issues like interfering traffic, signal to noise ratio fluctuations etc. One of the limitations within mobile networks is the low transmission bit rate which demands the reduction of the transmited video resolution and a high efficient video compression technique such as H.264 / A VC video compression standard. Video compression is based on the elimination of the spatial and temporal redundancies within the video sequence which makes the video stream more vulnerable against bit stream errors causing degradation in the quality of the received video. Several error resilience video coding schemes have been proposed to make the compressed bitstream resilient to transmission errors from different angles. Among one of them is error concealment techniques.
The objective of this thesis is to enhance the subjective and objective qualities of the received video sequences by proposing some spatial error concealment techniques that allow the concealment of the visual effect of bit stream error. Several modifications are being introduced on two previously proposed spatial error concealment techniques showing better results and a new contribution is being added by using the idea of boundary matching algorithm (BMA) previously used as an efficient temporal error concealment technique in the spatial domain for intra frame macroblock recovery.
Finally this work investigates the performance of each method in term of subjective and two objective image quality measures. Simulation results prove that the proposed spatial error concealment techniques improve the quality of reconstructed video~_