1设信源1234567()0
01XaaaaaaapX(1)求信源熵H(X);(2)编二进制香农码;(3)计算平均码长和编码效率
解:(1)721222222()()log()0
19log0
18log0
17log0
15log0
01log0
609/iiiHXpapabitsymbol(2)aip(ai)pa(aj)ki码字a10
203000a20
23001a30
393011a40
573100a50
743101a60
8941110a70
9971111110(3)71()0
141()()/2
1%iiiKkpxHXHXKR5
1的信源编二进制费诺码,计算编码效率
解:aip(ai)编码码字kia10
200002a20
19100103a30
1810113a40
1710102a50
15101103a60
11011104a70
011111142/55
3对信源编二进制和三进制哈夫曼码,计算各自的平均码长和编码效率
解:二进制哈夫曼码:xip(xi)编码码字kis61s50
610s40
391s30
350s20
261x10
20102x20
191112x30
1800003x40
1710013x50
1500103s10
111x60
1001104x70
01101114三进制哈夫曼码:xip(xi)编码码字kis31s20
540s10
261x10
2221x20
190002x30
181012x40
1720223/5x50
150102x60