clc;
clear?all;
Ip=imread（‘2.jpg‘）;

figure（1）;?
imshow（Ip）?
title（‘原始圖象‘）??????%顯示原圖?

I=double（Ip）;?????????????%將數據類型轉換為雙精度形式?
T=dctmtx（8）;?????????????%產生8*8的DCT變換系數矩陣?
B=blkproc（I[8?8]‘P1*x*P2‘TT‘）;?%對圖象I的每個8*8塊的DCT變換?
?Q=[16?11?10?16?24?40?51?61??
????12?12?14?19?26?58?60?55??
????14?13?16?24?40?57?69?56??
????14?17?22?29?51?87?80?60??
????18?22?37?56?68?109?103?77?
????24?25?55?64?81?104?113?92?
????49?64?78?87?103?121?120?101?
????72?92?95?98?112?100?103?99];??%標準量化矩陣?
?
B1=blkproc（B[8?8]‘round（x./P1）‘Q）;%對DCT系數矩陣進行有損量化?
?
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%??Z掃描?%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%?
?
?sx=[1?2?6?7?15?16?28?29??
????3?5?8?14?17?27?30?43??
????4?9?13?18?26?31?42?44??
????10?12?19?25?32?41?45?54?
????11?20?24?33?40?46?53?55?
????21?23?34?39?47?52?56?61??
????22?35?38?48?51?57?60?62?
????36?37?49?50?58?59?63?64];?
?
out=zeros（[1?8*8*64]）;?
??
for?a=1:8?
????for?b=1:8
????????for?i=1:8?
????????????for?j=1:8????
???????????????????out（（（a-1）*8+b）*64-64+sx（ij））=B1（a*8-8+ib*8-8+j）;?
????????????end??
????????end??
????end?
end?
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%?稀疏矩陣?游程編碼?%%%%%%%%%%%%%%%%%%%%%%%%%%%%?
?
r=1;?zero_num=0;?
for?i=1:4096
????if?out（i）~=0?
????????YC（r1）=zero_num;?
????????YC（r2）=out（i）;?
????????r=r+1;?
????????zero_num=0;?
????else?zero_num=zero_num+1;?
????end?
end?
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%?Huffman編碼?%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%?
?
%%%%%%?對游程編碼后的第一分量（0游程的個數）進行?Huffman編碼（1）?????%%%%%%%%%%%?
YC1=YC（:1）;[xy]=size（YC）?
sig=zeros（[max（xy）3]）;?
k=1;?sig（11）=YC1（1）;?
for?i=1:max（xy）?
????flag=0;?
????for?j=1:k?
????????if?sig（j1）==YC1（i）?
???????????sig（j2）=sig（j2）+1;?
???????????flag=1;?
???????????break?
????????end?
????end?
????if?flag==0?
????????k=k+1;?
????????sig（k1）=YC1（i）;?
????????sig（k2）=1;?
????end?
end?
?
sig=sig（1:k:）;?
?
SUM=sum（sig（:2））;?
sig（:3）=sig（:2）/SUM;?
?
[dict1avglen1]?=?huffmandict（sig（:1）sig（:3））;?%?Create?dictionary.?
actualsig1?=?YC1;??????????????????????%?actual?data??
comp1?=?huffmanenco（actualsig