function?dct2d?=?dct2d（Anum）
%?????A?=?imread（‘lena.bmp‘）;
????[row?col]?=?size（A）;
%?????imshow（A）;?????????????????????????????????????
%?????title（‘??‘）;
????image?=?double（A）;
????N?=?8;
????a（1）?=?sqrt（1/N）;
????a（2:8）?=?sqrt（2/N）;
????block?=?zeros（88）;?%divided?into?8*8?pixel?per?block
????d?=?zeros（88）;
????dct2d?=?zeros（512512）;
????if?num?==?1
????????mask?=??[1???0???0???0???0???0???0???0
?????????????????0???0???0???0???0???0???0???0
?????????????????0???0???0???0???0???0???0???0
?????????????????0???0???0???0???0???0???0???0
?????????????????0???0???0???0???0???0???0???0
?????????????????0???0???0???0???0???0???0???0
?????????????????0???0???0???0???0???0???0???0
?????????????????0???0???0???0???0???0???0???0];
????elseif?num?==?5
????????mask?=??[1???1???1???0???0???0???0???0
?????????????????1???1???0???0???0???0???0???0
?????????????????0???0???0???0???0???0???0???0
?????????????????0???0???0???0???0???0???0???0
?????????????????0???0???0???0???0???0???0???0
?????????????????0???0???0???0???0???0???0???0
?????????????????0???0???0???0???0???0???0???0
?????????????????0???0???0???0???0???0???0???0];
????elseif?num?==?10
????????mask?=?[1???1???1???1???0???0???0???0
??????????????????1???1???1???0???0???0???0???0
??????????????????1???1???0???0???0???0???0???0
??????????????????1???0???0???0???0???0???0???0
??????????????????0???0???0???0???0???0???0???0
??????????????????0???0???0???0???0???0???0???0
??????????????????0???0???0???0???0???0???0???0
??????????????????0???0???0???0???0???0???0???0];
????else
????????mask?=?[1???1???1???1???1???0???0???0
??????????????????1???1???1???1???1???0???0???0
??????????????????1???1???1???1???0???0???0???0
??????????????????1???1???1???0???0???0???0???0
??????????????????1???1???0???0???0???0???0???0
??????????????????1???0???0???0???0???0???0???0
??????????????????0???0???0???0???0???0???0???0
??????????????????0???0???0???0???0???0???0???0];
????end
????for?x?=?1?:?row/N
????????for?y?=?1?:?col/N
?????????????for?u?=?1?:?N
?????????????????for?v?=?1?:?N
?????????????????????d（uv）?=?0;
?????????????????????for?i?=?1?:?N
???????????????????????????for?j?=?1?:?N
?????????????????????????????block（ij）?=?image（i+（x-1）*8j+（y-1）*8）;
?????????????????????????????d（uv）?=?d（uv）?+?block（ij）?.*?cos（（2*（i-1）+1）*（u-1）*pi/（2*N））?.*?cos（（2*（j-1）+1）*（v-1）*pi/（2*N））;
???????????????????????????end
?????????????????????end
?????????????????????d（uv）?=?a（u）?.*?a（v）?.*?d（uv）;
?????????????????end
?????????????end
?????????????dct2d（（x-1）*8+1:x*8（y-1）*8+1:y*8）?=?d?.*?mask;
%??????????????display（d?.*?mask5）
????????end
????end
%?????figureimshow（uint8（dct2d））;title（‘DCT‘）;
end

?屬性????????????大小?????日期????時間???名稱
-----------?---------??----------?-----??----

?????文件???????2742??2017-04-07?16:10??5140309350_王寶來_作業1\dct2d.m

?????文件????????353??2017-04-07?14:39??5140309350_王寶來_作業1\DFT2D.m

?????文件????????853??2017-04-07?16:36??5140309350_王寶來_作業1\idct2d.m

?????文件????????382??2017-04-05?17:12??5140309350_王寶來_作業1\IDFT2D.m

?????文件?????263224??2005-08-08?04:51??5140309350_王寶來_作業1\lena.bmp

?????文件??????35000??2017-04-07?10:17??5140309350_王寶來_作業1\lena.jpg

?????文件???????2640??2017-04-07?10:09??5140309350_王寶來_作業1\lena_re.jpg

?????文件??????39143??2017-04-07?10:18??5140309350_王寶來_作業1\lina.jpg

?????文件???????2148??2017-04-07?10:08??5140309350_王寶來_作業1\lina_re.jpg

?????文件??????33320??2017-04-07?16:17??5140309350_王寶來_作業1\PSNR.jpg

?????文件????????248??2017-04-07?15:24??5140309350_王寶來_作業1\PSNR.m

?????文件????????526??2017-04-07?15:08??5140309350_王寶來_作業1\SOL1.m

?????文件????????694??2017-04-07?16:15??5140309350_王寶來_作業1\SOL2.m

?????文件??????82700??2017-04-07?12:20??5140309350_王寶來_作業1\time1.jpg

?????文件????1182513??2017-04-07?16:48??5140309350_王寶來_作業1\報告.docx

?????文件????????132??2017-04-07?16:50??5140309350_王寶來_作業1\說明.txt

?????目錄??????????0??2017-04-07?16:49??5140309350_王寶來_作業1

-----------?---------??----------?-----??----

??????????????1646618????????????????????17