Matlab内图片的拉伸

piday123

; E! }. z1 H+ P; H; _Matlab里面显示一张图片的话，长宽比取决于图片的横向纵向像素点数。
如果一张图片是433×433的话，那么imshow之后，就会按1比1比例显示，即使你拉伸窗口。
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; l4 ^7 b9 J* }; Xfname = 'frog.bmp';
A=imread(fname);
, U8 @! ?: I; E5 H5 fimshow(A);
set(gcf,'position',[100 100 400 800]);
效果如下:


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! X9 }  n  R1 v3 j" ~' m怎么能让图片充满整个画框呢。可以用画图板打开，拉伸图片，然后重新保存。
: E( l8 ^0 f" N; s7 V/ O0 P或者写个函数
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B= figure_stretch(A,1,3);
0 m1 a2 Z/ f! w! h) g0 dfigure
imshow(B);
set(gcf,'position',[100 100 400 800]);
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效果如下:
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% j# a9 v/ @% P  A
figure_stretch函数如下：
function C=figure_stretch(fname,w_scale,h_scale)
; Z/ `9 g8 H2 w, W* g% Stretch the figure.
9 W0 M% m3 m, H7 a6 t% S* t8 q% Usage:
% C=figure_stretch(fname,w_scale,h_scale)
% fname        : name of the figure
9 W+ C. P5 G4 R- W. v% w_scale      : stretch scale in width
; q# e1 U/ j9 u/ \% h_scale      : stretch scale in hight
! t5 k: f2 g5 c3 l5 t% Example:
+ }2 V3 t* x: U( ?8 Q5 n$ Z4 G% fname = 'frog.bmp';
% B= B= figure_stretch(fname,1,3);
% figure
$ ]; H3 c$ Y, h. S; r2 }% imshow(B);
% Author :  Haiyang Cui
% EMail  :  ***
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A= imread(fname);
" ?$ M2 O, `: {) r[I,J,K]=size(A);
x0=1:J;
y0=1:I;
0 @7 O" [+ ~5 P! h! }[X0,Y0] = meshgrid(x0,y0);
4 k1 X8 T5 s3 B2 {' a- dI1 = floor(I*h_scale);
$ f* ~: m+ J% |, W( RJ1 = floor(J*w_scale);

R = A(:,:,1);
# {* J) A. S3 [7 [4 WG = A(:,:,2);
6 R( p9 a% }2 l1 E% IB = A(:,:,3);
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6 H7 I1 o- n3 @/ u0 |x = 1:J1;
9 ]: T$ F( N7 D( H* H7 ]y = 1:I1;
[X,Y] = meshgrid(x,y);
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' e- f! c* G* ?; c1 x9 C' zX = X*J/J1;
9 t2 h; |5 G: `9 ^1 u3 r& iY = Y*I/I1;
X = double(X);
1 S6 `  Z. b1 f1 j' _$ ]: YY = double(Y);
R = double(R);
$ }+ v, w6 ^' f8 B3 O% i1 U% Y9 RG = double(G);
B = double(B);
# H+ b1 B  Y. ?3 h* }%
R1 = interp2(X0,Y0,R,X,Y);
8 k1 Z! |; c% N7 j( }* u' BG1 = interp2(X0,Y0,G,X,Y);
B1 = interp2(X0,Y0,B,X,Y);
C(:,:,1)=uint8(R1);
C(:,:,2)=uint8(G1);
C(:,:,3)=uint8(B1);
end

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CCxiaom

Matlab内图片的拉伸