圖像高通和低通濾波處理

1、acheandontmecntroi prob s e g ersccor diggot hee qUe drouhootig.eg aionfom.-g nedbyhosee sonsibeort hese cuiyte unifrhe.s.e “，h"aa,eope nmiema nageroncoamine pi_Ui onjobdisr Uwihi nobecuhi. - ntroueSooig an.gver nanc_ i de porlulise sponsiefr ntDpuyM aagerte "nagew oriuhepaaggahunstucci on

2、teamhea dadhe busie ss-amet headMembe radrumaite nancepesonne aeshoui .accrdigtotherdu ange .npro.cinequime”.eWee nvionme n“ecsfse_I，i_enfochecka nue porta -，. nreciicainprogrammeforhi .- igo'ernaceFourlope np - ife donisesonsibeol_u>ev_ pro.cina roubesoo. anagemeta i de porig ofccm pr eensv&

3、gt;work.AIcescopea ndfocuste nspecionpeann-var> "er>ig.esnneleoreaangovea n.silbeforeheui ”.”.cacm pree .svlsecl onofiqupmeu uningle 一 一實(shí)驗(yàn)五圖像高通和低通濾波處理1、 實(shí)驗(yàn)?zāi)康恼莆粘Ｓ妙l域高通濾波器和低通濾波器的設(shè)計(jì)。進(jìn)一步加深理解和掌握 圖像頻譜的特點(diǎn)和頻域高通濾波及頻域低通濾波的原理。理解圖象高通 濾波和低通濾波的處理過程和特點(diǎn)。2、 實(shí)驗(yàn)要求1 .實(shí)驗(yàn)之前要預(yù)習(xí)2 .獨(dú)立完成程序的編寫3 .寫出實(shí)驗(yàn)報(bào)告4 .實(shí)驗(yàn)每組1人實(shí)驗(yàn)設(shè)備：

4、每組計(jì)算機(jī)一臺(tái)3、 實(shí)驗(yàn)原理低通濾波器：容許低頻信號(hào)通過，但減弱（或減少）頻率高於截止頻率的信 號(hào)的通過。用在繪制長期走勢或均化。高通濾波器：容許高頻信號(hào)通過、但減弱（或減少）頻率低於截止頻率信號(hào) 通過的濾波器。強(qiáng)調(diào)細(xì)節(jié)。R1 一二 低通濾波器原理圖】二維理想高通濾波器的傳遞函數(shù)為：0D u v9 DH(u, v尸 1D u ,v ) DD0是從頻率矩形中點(diǎn)測得的截止頻率長度，它將以D0為半徑的圓周內(nèi)的所有頻率置零，而毫不衰減地通過圓周外的任何頻率。但其物理上是不可實(shí)現(xiàn)的。巴特沃斯高通濾波器的傳遞函數(shù)為：1H(u,v)：1 -D(u,v)式中D0為截止頻率距遠(yuǎn)點(diǎn)距離。與低通濾波器的情況一樣，可

5、認(rèn)為巴特沃斯高通型濾波器比IHPF更平滑。高斯高通濾波器傳遞函數(shù)為：H(u,v) =1 _eH2(u,v)/2D02高通濾波器能夠用高斯型低通濾波器的差構(gòu)成。這些不同的濾波器有更多的參數(shù)，因此能夠?qū)V波器的形狀進(jìn)行更多的控制。4、 實(shí)驗(yàn)內(nèi)容1 .對數(shù)字圖象進(jìn)行低通濾波處理2 .對數(shù)字圖象進(jìn)行高通濾波處理3 .比較和分析所得到的結(jié)果。5、 實(shí)驗(yàn)過程1 .流程圖開始2 .試驗(yàn)程序% 選擇圖片路徑及顯示 global feonduy dui ngma.requipme.r hhuuefea ndalele s.toe sgnae isbatudesandle opea.no-u pmenlnt hi

6、equ pmetadUe c.n.s2e-ipmentepae ime "os cmane nauuheUaleislWceawektkee quipmeanddee ctvldei c oi nura-he.n- ncyl nspedon. Tem- d edU dtle ip ti fi i i-ithesupeofmaite nanceesonnel udesa Idloanbeauandinspeuinoffkylqupment，aragah"eowneauSonalaUeUnicapesnne souldbeuarie dou - lyalew. steVsiln

7、se Uin.Eve ningCcntr oloom-.sdonua samsponta ne usumbust onunde.oubesooi.hepjandllid afi1 hmov gra d r walsteafeyupevi son.nuonndi ntiu - impeme ntt itficatonmesursProouCineUnol I gye uin：ise sonsbe.r.ul -hooti ngWe heexistS upe pacyuanSupe%選擇圖片路徑filename,pathname= .uigetfile('*.bmp''*.j

8、pg''*gif''*tif','%打開文件類型，對話框名稱f=imread(pathname filename);axes(handles.axes1);%.表示與下行連接 選擇圖片');%在 axes1 顯示原圖像imshow(f) ;title('原始圖像')；% - Executes on selection change in popupmenu1.function popupmenu1_Callback(hObject, eventdata, handles)% hObject handle to popupm

9、enu1 (see GCBO)% eventdata reserved - to be defined in a future version of MATLAB% handles structure with handles and user data (see GUIDATA)% Hints: contents = get(hObject,'String') returns popupmenu1 contents as cell array%contentsget(hObject,'Value') returns selected item from pop

10、upmenu1global fva=get(handles.popupmenu1,'Value');val=get(hObject,'Value');switch val%用 switch 語句設(shè)置選項(xiàng)case 1g=fft2(f);g=fftshift(g);M,N=size(g);nn=2;d0=20;m=fix(M/2);n=fix(N/2);for i=1:M%巴特沃斯高通濾波器% 傅立葉變換% 轉(zhuǎn)換數(shù)據(jù)矩陣% 二階 Butterworth 高通濾波器%截止頻率為10for j=1:Nd=sqrt(i-m)A2+(j-n)A2);h=1/(1+d0/(0

11、.414*d)A(2*nn);%計(jì)算高通濾波器傳遞函數(shù) result(i,j)=h*g(i,j);endendresult=ifftshift(result);y2=ifft2(result);y3=uint8(real(y2);axes(handles.axes2);imshow(y3); % 顯示濾波處理后的圖像title('巴特沃斯高通濾波);case 2%巴特沃斯低通濾波g=fft2(f);g=fftshift(g);% 傅立葉變換% 轉(zhuǎn)換數(shù)據(jù)矩陣ached)andon-timecontrol problems;severitygreaterrisk,accor dingtot

12、 here quire dtroubleshooting,registratictacom prehe nsiveinspecti onofequi pment,r unningthe squadl eaM,N=size(g); nn=2;d0=30;m=fix(M/2);n=fix(N/2);for i=1:M%二階巴特沃斯(Butterworth)低通濾波器%截止頻率為10for j=1:Nd=sqrt(i-m)A2+(j-n)A2);h=1/(1+0.414*(d/d0)A(2*nn);% 計(jì)算低通濾波器傳遞函數(shù) result(i,j)=h*g(i,j);endendresult=iff

13、tshift(result);y2=ifft2(result);y3=uint8(real(y2);axes(handles.axes3);imshow(y3); % 顯示濾波處理后的圖像title('巴特沃斯低通濾波')case 3 %理想高通濾波k=fft2(f);% 傅立葉變換g=fftshift(k);% 轉(zhuǎn)換數(shù)據(jù)矩陣M,N=size(g);d0=10;%截止頻率為10m=fix(M/2);n=fix(N/2);for i=1:Mfor j=1:Nd=sqrt(i-m)A2+(j-n)A2); % 計(jì)算高通濾波器傳遞函數(shù) if d<=d0h=0;else h=1;

14、endresult(i,j)=h*g(i,j);endendresult=ifftshift(result);y2=ifft2(result);y3=uint8(real(y2);axes(handles.axes4);imshow(y3);title('理想高通濾波)case 4 k=fft2(f);% 理想低通濾波% 傅立葉變換% 轉(zhuǎn)換數(shù)據(jù)矩陣g=fftshift(k);acheandontmecntroi prob s e g ersccor diggot hee qUe drouhootig.eg aionfom.-g nedbyhosee sonsibeort hese cu

15、iyte unifrhe.s.e “，h"aa,eope nmiema nageroncoamine pi_Ui onjobdisr Uwihi nobecuhi. - ntroueSooig an.gver nanc_ i de porlulise sponsiefr ntDpuyM aagerte "nagew oriuhepaaggahunstucci onteamhea dadhe busie ss-amet headMembe radrumaite nancepesonne aeshoui .accrdigtotherdu ange .npro.cinequime

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20、ndresult(i,j)=h*g(i,j);endendresult=ifftshift(result);y2=ifft2(result);y3=uint8(real(y2);axes(handles.axes5);imshow(y3);title('理想低通濾波')end;3.實(shí)驗(yàn)結(jié)果eonduy dui ngma.requipme.r hhuuefea ndalele s.toe sgnae isbatudesandle opea.no-u pmenlnt hiequ pmetadUe c.n.s2e-ipmentepae ime "os cmane nauuh

21、eUaleislWceawektkee quipmeanddee ctvldei c oi nura-he.n- ncyl nspedon. Tem- d edU dtle ip ti fi i i-ithesupeofmaite nanceesonnel udesa Idloanbeauandinspeuinoffkylqupment，aragah"eowneauSonalaUeUnicapesnne souldbeuarie dou - lyalew. steVsilnse Uin.Eve ningCcntr oloom-.sdonua samsponta ne usumbust

22、 onunde.oubesooi.hepjandllid afi1 hmov gra d r walsteafeyupevi son.nuonndi ntiu - impeme ntt itficatonmesursProouCineUnol I gye uin：ise sonsbe.r.ul -hooti ngWe heexistS upe pacyuanSupeacheandontmecntroi prob s e g ersccor diggot hee qUe drouhootig.eg aionfom.-g nedbyhosee sonsibeort hese cuiyte unif

23、rhe.s.e “，h"aa,eope nmiema nageroncoamine pi_Ui onjobdisr Uwihi nobecuhi. - ntroueSooig a n.over nanc_ i de porlulise sponsiefr ntDpUyM aagerte "nagew oriuhepaaggahunstucci onteamhea dadhe busie ss-amet headMembe radrumaite nancepesonne aeshoui .accrdigtotherdu ange .npro.cinequime”.eWee n

24、vionme n“ecsfse_I，i_enfochecka nue porta -，. nreciicainprogrammeforhi .- igo'ernaceFourlope np - ife donisesonsibeol_u>ev_ pro.cina roubesoo. anagemeta i de porig ofccmpr eensv>work.AIcescopea ndfocuste nspecionpeann-var> "er>ig.esnneleoreaangovea n.silbeforeheui ”.”.cacm pree .svlsecl onofiqupmeu u