-壓縮和熵編碼

平時(shí)作業(yè)9（必做）：對(duì)下列符號(hào)進(jìn)行Huffman編碼，并計(jì)算壓縮比。符號(hào)及其在圖像中出現(xiàn)的數(shù)目符號(hào)出現(xiàn)的次數(shù)40 10 515出現(xiàn)的次數(shù)40 10 5152010各個(gè)字母出現(xiàn)的頻率由大到小排列：字母頻率0.40.20.150.10.10.05Huffman編碼二叉樹圖平均碼長(zhǎng)：1*0.4+2*0.2+3*0.15+4*0.1+5*0.1+5*0.05=2.4頻率0.40.20.150.10.10.05Huffman編碼二叉樹圖平均碼長(zhǎng)：1*0.4+2*0.2+3*0.15+4*0.1+5*0.1+5*0.05=2.4壓縮比：1.25:1平時(shí)作業(yè)10（必做）：寫出串“goodnight”（注意當(dāng)中的空格符）之算術(shù)編碼的編解碼過(guò)程。將該字符串中所包含的八個(gè)字符，按照字母順序排列，計(jì)算各自出現(xiàn)的頻率，和其所對(duì)應(yīng)的區(qū)間，如下：順序字母頻率1（空格）0.0-0.12d0.1-0.23g0.2-0.44h0.4-0.55i0.5-0.66n0.6-0.77o0.7-0.98t0.9-1.0編碼過(guò)程表序號(hào)符號(hào)lr初值010g(0+1*0.2)=0.20+1*0.4=0.41o(0.2+0.2*0.4)=0.280.2+0.2*0.5=0.32o(0.28+0.02*0.4)=0.2880.28+0.02*0.5=0.293d0.288+0.002*0.1=0.28820.288+0.002*0.2=0.28844（空格）0.2882+0.0002*0=0.28820.2882+0.0002*0.1=0.2885n0.2882+0.00002*0.6=0.28820.2882+0.00002*0.7=0.2886i0.2882130.2882132

7g0.288213020.288213088h0.288213040.288213059t0.288213050.288213051解碼過(guò)程表jvic=s10.441065253g2(0.44106525-0.2)/0.2=0.844261127o3(0.84426112-0.7)/0.2=0.721305677o4(0.72130567-0.7)/0.2=0.1065282d5(0.106528-0.1)/0.1=0.0652816(0.06528-0)/0.1=0.65286n7(0.6528-0.6)/0.1=0.5285i8(0.528-0.5)/0.1=0.283g9(0.28-0.2)/0.2=0.44h10(0.4-0.8)/0.1=08t恩，這個(gè)答案怎么不一樣呢？太難算了。。。。平時(shí)作業(yè)11(必做)：對(duì)字符串“ababcbababaaaaaaa”進(jìn)行手工LZW編解碼。步驟輸出字符(1)a2)b

3)c4)ab1b5)ba2b6)abc