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Performance Analysis

 In this section we discuss the performance of the adaptive quantizer and on-line channel estimator. Figure 10-Figure 12 show the convergence of the linear LRI learning to the optimal quantizer when pe=10-1. It is seen that p1(n) corresponding to the optimal quantizer converges to 1 and p2(n) and p3(n) converge to zero for all the three sequences. Both p2(n) and p3(n) have the same behavior as n varies. This is why we see only one dotted curve in the figures. We also observe that increasing the value of the reward parameter results in a faster learning. We find similar convergence results for other bit error probabilities and other video sequences too.

Figure 13 shows the reconstructed frames of the Missamerica sequence when pe=10-1. Clearly, the optimal quantizer when M=2 results in a decrease in the number of corrupted blocks. A similar behavior is seen in Figure 14 when p2=10-2. This performance can be further enhanced by using additional error protection.