function?[comp_image_Ycomp_image_Ucomp_image_V]?=?Compress（orig_image）
RGB=orig_image;
%下面是對?RGB?三個分量進行分離?
R=RGB（::1）;
G=RGB（::2）;
B=RGB（::3）;
%RGB->YUV?Y=0.299*double（R）+0.587*double（G）?+0.114*double（B）;?
[xm?xn]?=?size（Y）;?????????????
U=-0.169*double（R）-0.3316*double（G）+0.5*double（B）;?
V=0.5*double（R）-0.4186*double（G）-0.0813*double（B）;
%產生一個?8*8?的?DCT?變換舉證?
T=dctmtx（8）;
%進行?DCT?變換?BY?BU?BV?是?double?類型
BY=blkproc（Y[8?8]‘P1*x*P2‘TT‘）;?
BU=blkproc（U[8?8]‘P1*x*P2‘TT‘）;?
BV=blkproc（V[8?8]‘P1*x*P2‘TT‘）;?????%低頻分量量化表
a=[
16?11?10?16?24?40?51?61;
12?12?14?19?26?58?60?55;
14?13?16?24?40?57?69?55;
14?17?22?29?51?87?80?62;
18?22?37?56?68?109?103?77;?
24?35?55?64?81?104?113?92;??????????????????????
49??64?78?87?103?121?120?101;???????????????????
72?92?95?98?112?100?103?99;
];?%高頻分量量化表
b=[17?18?24?47?99?99?99?99;?
18?21?26?66?99?99?99?99;?
24?26?56?99?99?99?99?99;?
47?66?99?99?99?99?99?99;?
99?99?99?99?99?99?99?99;?
99?99?99?99?99?99?99?99;?
99?99?99?99?99??99?99?99;?
99?99?99?99?99?99?99?99;];
%使用量化表對三個分量進行量化?
BY2=blkproc（BY[8?8]‘round（x./P1）‘a）;?
BU2=blkproc（BU[8?8]‘round（x./?P1）‘b）;?
BV2=blkproc（BV[8?8]‘round（x./P1）‘b）;
%調用壓縮函數(shù)?
comp_image_Y=img2jpg（BY21）;????????
comp_image_U=img2jpg（BU22）;????????????????????
comp_image_V=img2jpg（BV23）;

?屬性????????????大小?????日期????時間???名稱
-----------?---------??----------?-----??----
?????目錄???????????0??2018-11-02?08:12??JPEG\
?????文件??????153275??2018-10-29?22:32??JPEG\1.jpg
?????文件??????196671??2018-10-29?22:32??JPEG\2.jpg
?????文件??????323027??2018-10-29?22:32??JPEG\3.jpg
?????文件???????78736??2018-10-29?22:33??JPEG\4.jpg
?????文件????????1393??2018-11-01?18:10??JPEG\Compress.m
?????文件?????????222??2018-11-01?17:52??JPEG\dct.m
?????文件?????????358??2018-11-01?18:14??JPEG\Decompress.m
?????文件???????12808??2018-10-29?22:04??JPEG\image.jpg
?????文件????????1122??2018-11-01?18:11??JPEG\img2jpg.m
?????文件????????1972??2018-11-01?18:13??JPEG\jpg2img.m