58.imhist
功能:
显示图像数据的柱状图.
语法:
imhist(I,n)
imhist(X,map)
[counts,x] = imhist(...)
举例
I = imread('pout.tif');
imhist(I)
附录 MATLAB图像处理命令 347
相关命令:
histeq
59.immovie
功能:
创建多帧索引图的电影动画.
语法:
mov = immovie(X,map)
举例
load mri
mov = immovie(D,map);
相关命令:
montage
60.imnoise
功能:
增加图像的渲染效果.
语法:
J = imnoise(I,type)
J = imnoise(I,type,parameters)
举例
I = imread('eight.tif');
J = imnoise(I,'salt & pepper',0.02);
imshow(I)
figure, imshow(J)
相关命令:
rand
61.impixel
功能:
确定像素颜色值.
语法:
MATLAB高级应用——图形及影像处理 348
P = impixel(I)
P = impixel(X,map)
P = impixel(RGB)
P = impixel(I,c,r)
P = impixel(X,map,c,r)
P = impixel(RGB,c,r)
[c,r,P] = impixel(...)
P = impixel(x,y,I,xi,yi)
P = impixel(x,y,X,map,xi,yi)
P = impixel(x,y,RGB,xi,yi)
[xi,yi,P] = impixel(x,y,...)
举例
RGB = imread('flowers.tif');
c = [12 146 410];
r = [104 156 129];
pixels = impixel(RGB,c,r)
pixels =
61 59 101
253 240 0
237 37 44
相关命令:
improfile, pixval
62.improfile
功能:
沿线段计算剖面图的像素值.
语法:
c = improfile
c = improfile(n)
c = improfile(I,xi,yi)
c = improfile(I,xi,yi,n)
[cx,cy,c] = improfile(...)
[cx,cy,c,xi,yi] = improfile(...)
[...] = improfile(x,y,I,xi,yi)
[...] = improfile(x,y,I,xi,yi,n)
附录 MATLAB图像处理命令 349
[...] = improfile(...,method)
举例
I = imread('alumgrns.tif');
x = [35 338 346 103];
y = [253 250 17 148];
improfile(I,x,y), grid on
相关命令:
impixel, pixval
63.imread
功能:
从图形文件中读取图像.
语法:
A = imread(filename,fmt)
[X,map] = imread(filename,fmt)
[...] = imread(filename)
[...] = imread(...,idx) (TIFF only)
[...] = imread(...,ref) (HDF only)
[...] = imread(...,'BackgroundColor',BG) (PNG only)
[A,map,alpha] = imread(...) (PNG only)
举例
[X,map] = imread('flowers.tif',6);
info = imfinfo('skull.hdf');
[X,map] = imread('skull.hdf',info(4).Reference);
bg = [255 0 0];
A = imread('image.png','BackgroundColor',bg);
MATLAB高级应用——图形及影像处理 350
[A,map,alpha] = imread('image.png');
相关命令:
imfinfo, imwrite,fread,double,uint8,uint16
64.imresize
功能:
改变图像大小.
语法:
B = imresize(A,m,method)
B = imresize(A,[mrows ncols],method)
B = imresize(...,method,n)
B = imresize(...,method,h)
65.imrotate
功能:
旋转图像.
语法:
B = imrotate(A,angle,method)
B = imrotate(A,angle,method,'crop')
举例
I = imread('ic.tif');
J = imrotate(I,-4,'bilinear','crop');
imshow(I)
figure, imshow(J)
相关命令:
imcrop, imresize
66.imshow
功能:
显示图像.
语法:
附录 MATLAB图像处理命令 351
imshow(I,n)
imshow(I,[low high])
imshow(BW)
imshow(X,map)
imshow(RGB)
imshow(...,display_option)
imshow(x,y,A,...)
imshow filename
h = imshow(...)
相关命令:
getimage, imread, iptgetpref, iptsetpref, subimage, truesize, warp
67.imwrite
功能:
把图像写入图形文件中.
语法:
imwrite(A,filename,fmt)
imwrite(X,map,filename,fmt)
imwrite(...,filename)
imwrite(...,Param1,Val1,Param2,Val2...)
举例
imwrite(X,map,'flowers.hdf','Compression','none',...
'WriteMode','append')
相关命令:
imfinfo, imread
68.ind2gray
功能:
把检索图像转化为灰度图像.
语法:
I = ind2gray(X,map)
举例
load trees
I = ind2gray(X,map);
imshow(X,map)
figure,imshow(I)
MATLAB高级应用——图形及影像处理 352
相关命令:
gray2ind, imshow, rgb2ntsc
69.ind2rgb
功能:
转化索引图像为RGB真彩图像.
语法:
RGB = ind2rgb(X,map)
相关命令:
ind2gray, rgb2ind
70.iptgetpref
功能:
获取图像处理工具箱参数设置.
语法:
value = iptgetpref(prefname)
举例
value = iptgetpref('ImshowAxesVisible')
value =
off
相关命令:
imshow, iptsetpref
71.iptsetpref
功能:
设置图像处理工具箱参数.
语法:
iptsetpref(prefname,value)
举例
iptsetpref('ImshowBorder','tight')
相关命令:
imshow, iptgetpref, truesize
72.iradon
附录 MATLAB图像处理命令 353
功能:
进行反Radon变换.
语法:
I = iradon(P,theta)
I = iradon(P,theta,interp,filter,d,n)
[I,h] = iradon(...)
举例
P = phantom(128);
R = radon(P,0:179);
I = iradon(R,0:179,'nearest','Hann');
imshow(P)
figure, imshow(I)
相关命令:
radon, phantom
73.isbw
功能:
判断是否为二进制图像.
语法:
flag = isbw(A)
相关命令:
isind, isgray, isrgb
74.isgray
功能:
判断是否为灰度图像.
语法:
flag = isgray(A)
相关命令:
isbw, isind, isrgb
75.isind
MATLAB高级应用——图形及影像处理 354
功能:
判断是否为索引图像.
语法:
flag = isind(A)
相关命令:
isbw, isgray, isrgb
76.isrgb
功能:
判读是否为RGB真彩图像.
语法:
flag = isrgb(A)
相关命令:
isbw, isgray, isind
77.makelut
功能:
创建一个用于applylut函数的lookup表.
语法:
lut = makelut(fun,n)
lut = makelut(fun,n,P1,P2,...)
举例
f = inline('sum(x(:)) >= 2');
lut = makelut(f,2)
lut =
0
0
0
1
0
1
1
1
0
1
1
1
1
1
附录 MATLAB图像处理命令 355
1
1
相关命令:
applylut
78.mat2gray
功能:
转化矩阵为灰度图像.
语法:
I = mat2gray(A,[amin amax])
I = mat2gray(A)
举例
I = imread('rice.tif');
J = filter2(fspecial('sobel'),I);
K = mat2gray(J);
imshow(I)
figure, imshow(K)
相关命令:
gray2ind
79.mean2
功能:
计算矩阵元素的平均值.
语法:
b = mean2(A)
相关命令:
std2, mean, std
80.medfilt2
功能:
进行二维中值过滤.
语法:
MATLAB高级应用——图形及影像处理 356
B = medfilt2(A,[m n])
B = medfilt2(A)
B = medfilt2(A,'indexed',...)
举例
I = imread('eight.tif');
J = imnoise(I,'salt & pepper',0.02);
K = medfilt2(J);
imshow(J)
figure, imshow(K)
相关命令:
filter2, ordfilt2, wiener2
81.montage
功能:
在矩形框中同时显示多幅图像.
语法:
montage(I)
montage(BW)
montage(X,map)
montage(RGB)
h = montage(...)
举例
load mri
montage(D,map)
附录 MATLAB图像处理命令 357
相关命令:
immovie
82.nlfilter
功能:
进行边沿操作.
语法:
B = nlfilter(A,[m n],fun)
B = nlfilter(A,[m n],fun,P1,P2,...)
B = nlfilter(A,'indexed',...)
举例
B = nlfilter(A,[3 3],'median(x(:))');
相关命令:
blkproc, colfilt
83.ntsc2rgb
功能: 转换NTSC的值为RGB颜色空间.
语法:
rgbmap = ntsc2rgb(yiqmap)
RGB = ntsc2rgb(YIQ)
相关命令:
rgb2ntsc, rgb2ind, ind2rgb, ind2gray
84.ordfilt2
功能:
进行二维统计顺序过滤.
语法:
B = ordfilt2(A,order,domain)
B = ordfilt2(A,order,domain,S)
MATLAB高级应用——图形及影像处理 358
B = ordfilt2(...,padopt)
相关命令:
medfilt2
85.phantom
功能:
产生一个头部幻影图像.
语法:
P = phantom(def,n)
P = phantom(E,n)
[P,E] = phantom(...)
举例
P = phantom('Modified Shepp-Logan',200);
imshow(P)
相关命令:
radon, iradon
86.pixval
功能:
显示图像像素信息.
语法:
pixval on
pixval off
pixval
pixval(fig,option)
相关命令:
impixel, improfile
87.qtdecomp
功能:
进行四叉树分解.
附录 MATLAB图像处理命令 359
语法:
S = qtdecomp(I)
S = qtdecomp(I,threshold)
S = qtdecomp(I,threshold,mindim)
S = qtdecomp(I,threshold,[mindim maxdim])
S = qtdecomp(I,fun)
S = qtdecomp(I,fun,P1,P2,...)
举例
I = [1 1 1 1 2 3 6 6
1 1 2 1 4 5 6 8
1 1 1 1 10 15 7 7
1 1 1 1 20 25 7 7
20 22 20 22 1 2 3 4
20 22 22 20 5 6 7 8
20 22 20 20 9 10 11 12
22 22 20 20 13 14 15 16];
S = qtdecomp(I,5);
full(S)
ans =
4 0 0 0 2 0 2 0
0 0 0 0 0 0 0 0
0 0 0 0 1 1 2 0
0 0 0 0 1 1 0 0
4 0 0 0 2 0 2 0
0 0 0 0 0 0 0 0
0 0 0 0 2 0 2 0
0 0 0 0 0 0 0 0
相关命令:
qtgetblk, qtsetblk
88.qtgetblk
功能:
获取四叉树分解中的块值.
语法:
[vals,r,c] = qtgetblk(I,S,dim)
MATLAB高级应用——图形及影像处理 360
[vals,idx] = qtgetblk(I,S,dim)
举例
[vals,r,c] = qtgetblk(I,S,4)
vals(:,:,1) =
1 1 1 1
1 1 2 1
1 1 1 1
1 1 1 1
vals(:,:,2) =
20 22 20 22
20 22 22 20
20 22 20 20
22 22 20 20
r =
1
5
c =
1
1
相关命令:
qtdecomp, qtsetblk