離散余弦轉(zhuǎn)換課件

第二章

離散餘弦轉(zhuǎn)換

(DCT)1第二章

離散餘弦轉(zhuǎn)換

(DCT)1Outlines頻率域表示法(FrequencyDomain)離散餘弦轉(zhuǎn)換(DCT)離散餘弦轉(zhuǎn)換公式基頻影像，影像頻率，影像邊緣，影像能量離散餘弦轉(zhuǎn)換的例子快速離散餘弦轉(zhuǎn)換傳統(tǒng)DCTversus快速DCT2Outlines頻率域表示法(FrequencyDoma頻率域表非法3頻率域表非法3頻率域表示法(cont.)4頻率域表示法(cont.)4

f(x,y)=O(x,y)-128FDCT(f(x,y)|x=0toN;y=0toN)

(x,y)(i,j)O(x,y)=f(x,y)+128IDCT(D(i,j)|i=0toN;j=0toN)空間域頻率域離散餘弦轉(zhuǎn)換5f(x,y)=離散餘弦轉(zhuǎn)換公式ForwardDCT(FDCT):InverseDCT(IDCT):ifxis0,else16離散餘弦轉(zhuǎn)換公式ForwardDCT(FDCT):In

空間域頻率域(8X8)DCT二維基頻影像DCAC基頻影像7

基頻影像頻率圖8基頻影像頻率圖8基頻影像邊緣分佈圖9基頻影像邊緣分佈圖9基頻影像能量分佈圖10基頻影像能量分佈圖10離散餘弦轉(zhuǎn)換的例子頻率域原始資料陣列:0:20000000001:000000002:000000003:000000004:000000005:000000006:000000007:00000000IDCT轉(zhuǎn)換後的結(jié)果:0:1531531531531531531531531:1531531531531531531531532:1531531531531531531531533:1531531531531531531531534:1531531531531531531531535:1531531531531531531531536:1531531531531531531531537:153153153153153153153153所對(duì)照的影像

11離散餘弦轉(zhuǎn)換的例子頻率域原始資料陣列:所對(duì)照的影像11離散餘弦轉(zhuǎn)換的例子(cont.)頻率域原始資料陣列:0:00000002001:000000002:000000003:000000004:000000005:000000006:000000007:00000000IDCT轉(zhuǎn)換的結(jié)果:

0:13510815793163991481211:13510815793163991481212:13510815793163991481213:13510815793163991481214:13510815793163991481215:13510815793163991481216:13510815793163991481217:1351081579316399148121所對(duì)照的影像

12離散餘弦轉(zhuǎn)換的例子(cont.)頻率域原始資料陣列:所對(duì)照離散餘弦轉(zhuǎn)換的例子(cont.)頻率域原始資料陣列:0:000000001:000000002:000000003:000000004:000000005:000000006:000000007:2000000000IDCT轉(zhuǎn)換的結(jié)果:0:1351351351351351351351351:1081081081081081081081082:1571571571571571571571573:93939393939393934:1631631631631631631631635:99999999999999996:1481481481481481481481487:121121121121121121121121所對(duì)照的影像

13離散餘弦轉(zhuǎn)換的例子(cont.)頻率域原始資料陣列:所對(duì)照離散餘弦轉(zhuǎn)換的例子(cont.)14離散餘弦轉(zhuǎn)換的例子(cont.)14離散餘弦轉(zhuǎn)換的例子(c