图像正交变换
2009-05-24 12:50
197 查看
关键词:
实验1 :
>> f=imread('fouriertest.jpg');
>> imshow(f,'notruesize')
Warning: IMSHOW(...,'notruesize') is an obsolete syntax.
Use IMSHOW(...,'InitialMagnification','fit') instead.
> In imshow>preParseInputs at 293
In imshow at 149
>> F=fft2(f);
Warning: FFTN on values of class UINT8 is obsolete.
Use FFTN(DOUBLE(X)) or FFTN(SINGLE(X)) instead.
> In uint8.fftn at 10
In fft2 at 19
>> mesh(fftshift(abs(F)));
这就是fft变换后的频谱图;
>> F2=fftshift(log(abs(F)));
>> imshow(F2,[-1,5],'notruesize');%显示频谱图像,频谱的零频率系数被移至频率中间
Warning: IMSHOW(...,'notruesize') is an obsolete syntax.
Use IMSHOW(...,'InitialMagnification','fit') instead.
> In imshow>preParseInputs at 293
In imshow at 149
f=zeros(1000,1000);
f(350:649,475:524)=1;
f=imrotate(f,45,'bilinear','crop');
imshow(f,'notruesize');
Warning: IMSHOW(...,'notruesize') is an obsolete syntax.
Use IMSHOW(...,'InitialMagnification','fit') instead.
In imshow>preParseInputs at 293
In imshow at 149
>> title('图像正向旋转45°');
>> subplot(224)
>> F=fftshift(abs(fft2(f)));
>> imshow(F,[-1 5],'notruesize');
Warning: IMSHOW(...,'notruesize') is an obsolete syntax.
Use IMSHOW(...,'InitialMagnification','fit') instead.
> In imshow>preParseInputs at 293
In imshow at 149
>>
>> f=zeros(1000,1000);
f(50:349,475:524)=1;
imshow(f, 'notruesize');
Warning: IMSHOW(...,'notruesize') is an obsolete syntax.
Use IMSHOW(...,'InitialMagnification','fit') instead.
> In imshow>preParseInputs at 293
In imshow at 149
>>
F=fftshift(abs(fft2(f)));
>>
>> imshow(F,[-1 5], 'notruesize');
Warning: IMSHOW(...,'notruesize') is an obsolete syntax.
Use IMSHOW(...,'InitialMagnification','fit') instead.
> In imshow>preParseInputs at 293
In imshow at 149
>>
>> f=zeros(1000,1000);
>> f(350:640,475:524)=1;
>> subplot(221)
>> imshow(f,'notruesize');
Warning: IMSHOW(...,'notruesize') is an obsolete syntax.
Use IMSHOW(...,'InitialMagnification','fit') instead.
> In imshow>preParseInputs at 293
In imshow at 149
>> subplot(221)
>> imshow(f,'notruesize');
Warning: IMSHOW(...,'notruesize') is an obsolete syntax.
Use IMSHOW(...,'InitialMagnification','fit') instead.
> In imshow>preParseInputs at 293
In imshow at 149
>> title('原始图片');
>> subplot(222)
>> F=fftshift(abs(fft2(f)));
>> imshow(F,[-1 5],'notruesize');
Warning: IMSHOW(...,'notruesize') is an obsolete syntax.
Use IMSHOW(...,'InitialMagnification','fit') instead.
> In imshow>preParseInputs at 293
In imshow at 149
>> title('原始图像的傅里叶变换频谱');
>> subplot(223)
>> f=zeros(1000,1000);
>> f(350:649,800:849)=1;
>> imshow(f,'notruesize');
Warning: IMSHOW(...,'notruesize') is an obsolete syntax.
Use IMSHOW(...,'InitialMagnification','fit') instead.
> In imshow>preParseInputs at 293
In imshow at 149
>> title('向x轴方向移动后的图像');
>> subplot(224)
>> F=fftshift(abs(fft2(f)));
>> imshow(F,[-1 5] ,'notruesize');
Warning: IMSHOW(...,'notruesize') is an obsolete syntax.
Use IMSHOW(...,'InitialMagnification','fit') instead.
> In imshow>preParseInputs at 293
In imshow at 149
>> title('向x轴方向移动后的傅里叶变换频谱');
>>
实验1 :
>> f=imread('fouriertest.jpg');
>> imshow(f,'notruesize')
Warning: IMSHOW(...,'notruesize') is an obsolete syntax.
Use IMSHOW(...,'InitialMagnification','fit') instead.
> In imshow>preParseInputs at 293
In imshow at 149
>> F=fft2(f);
Warning: FFTN on values of class UINT8 is obsolete.
Use FFTN(DOUBLE(X)) or FFTN(SINGLE(X)) instead.
> In uint8.fftn at 10
In fft2 at 19
>> mesh(fftshift(abs(F)));
这就是fft变换后的频谱图;
>> F2=fftshift(log(abs(F)));
>> imshow(F2,[-1,5],'notruesize');%显示频谱图像,频谱的零频率系数被移至频率中间
Warning: IMSHOW(...,'notruesize') is an obsolete syntax.
Use IMSHOW(...,'InitialMagnification','fit') instead.
> In imshow>preParseInputs at 293
In imshow at 149
f=zeros(1000,1000);
f(350:649,475:524)=1;
f=imrotate(f,45,'bilinear','crop');
imshow(f,'notruesize');
Warning: IMSHOW(...,'notruesize') is an obsolete syntax.
Use IMSHOW(...,'InitialMagnification','fit') instead.
In imshow>preParseInputs at 293
In imshow at 149
>> title('图像正向旋转45°');
>> subplot(224)
>> F=fftshift(abs(fft2(f)));
>> imshow(F,[-1 5],'notruesize');
Warning: IMSHOW(...,'notruesize') is an obsolete syntax.
Use IMSHOW(...,'InitialMagnification','fit') instead.
> In imshow>preParseInputs at 293
In imshow at 149
>>
>> f=zeros(1000,1000);
f(50:349,475:524)=1;
imshow(f, 'notruesize');
Warning: IMSHOW(...,'notruesize') is an obsolete syntax.
Use IMSHOW(...,'InitialMagnification','fit') instead.
> In imshow>preParseInputs at 293
In imshow at 149
>>
F=fftshift(abs(fft2(f)));
>>
>> imshow(F,[-1 5], 'notruesize');
Warning: IMSHOW(...,'notruesize') is an obsolete syntax.
Use IMSHOW(...,'InitialMagnification','fit') instead.
> In imshow>preParseInputs at 293
In imshow at 149
>>
>> f=zeros(1000,1000);
>> f(350:640,475:524)=1;
>> subplot(221)
>> imshow(f,'notruesize');
Warning: IMSHOW(...,'notruesize') is an obsolete syntax.
Use IMSHOW(...,'InitialMagnification','fit') instead.
> In imshow>preParseInputs at 293
In imshow at 149
>> subplot(221)
>> imshow(f,'notruesize');
Warning: IMSHOW(...,'notruesize') is an obsolete syntax.
Use IMSHOW(...,'InitialMagnification','fit') instead.
> In imshow>preParseInputs at 293
In imshow at 149
>> title('原始图片');
>> subplot(222)
>> F=fftshift(abs(fft2(f)));
>> imshow(F,[-1 5],'notruesize');
Warning: IMSHOW(...,'notruesize') is an obsolete syntax.
Use IMSHOW(...,'InitialMagnification','fit') instead.
> In imshow>preParseInputs at 293
In imshow at 149
>> title('原始图像的傅里叶变换频谱');
>> subplot(223)
>> f=zeros(1000,1000);
>> f(350:649,800:849)=1;
>> imshow(f,'notruesize');
Warning: IMSHOW(...,'notruesize') is an obsolete syntax.
Use IMSHOW(...,'InitialMagnification','fit') instead.
> In imshow>preParseInputs at 293
In imshow at 149
>> title('向x轴方向移动后的图像');
>> subplot(224)
>> F=fftshift(abs(fft2(f)));
>> imshow(F,[-1 5] ,'notruesize');
Warning: IMSHOW(...,'notruesize') is an obsolete syntax.
Use IMSHOW(...,'InitialMagnification','fit') instead.
> In imshow>preParseInputs at 293
In imshow at 149
>> title('向x轴方向移动后的傅里叶变换频谱');
>>
相关文章推荐
- 图像的正交变换---沃尔什——哈达马变换
- 图像的正交变换---离散余弦变换
- 图像基本知识整理(3)——图像的正交变换
- 图像的正交变换----傅立叶变换
- 基于dct变换的图像编解码(包含Z扫描与反Z扫描)的matlab程序
- OpenCV实现基于8*8块DCT变换的图像压缩
- 【数字图像处理】灰度变换
- 小波变换在数字图像上的应用(下)
- OpenCV笔记8:一个简单的变换:图像的平滑
- OpenCV学习(六)之图像缩放变换
- 2-数字图像变换
- 图像变换:可分变换和不可分变换
- java图像处理之倒角距离变换
- 图像变换
- 用DFT变换处理图像
- OpenCV学习笔记(十六)——CamShift研究 OpenCV学习笔记(十七)——运动分析和物体跟踪Video OpenCV学习笔记(十八)——图像的各种变换(cvtColor*+)imgproc
- 傅里叶变换与图像处理
- OpenCV学习笔记(十八)——图像的各种变换(cvtColor*+)imgproc
- 6. 对一幅灰度图像进行离散傅里叶变换,用图像的形式显示其(中心化后的)频谱。改变频谱,在进行 反变换,观察变换前后的区别