Matlab内图片的拉伸

piday123

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。
% c) l6 a# B4 {& _% r1 R
fname = 'frog.bmp';
A=imread(fname);
imshow(A);
set(gcf,'position',[100 100 400 800]);
效果如下:
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* N3 H% {: w' j" [. o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。
- S( z8 ?8 A  C4 |1 \或者写个函数
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1 H  R: ]( m, X$ S, |B= figure_stretch(A,1,3);
figure
& E6 W. q$ P3 \/ q! H6 Q# J1 Timshow(B);
set(gcf,'position',[100 100 400 800]);
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- A8 D* R/ Y! y7 H/ m& m效果如下:
  Z( t" ^8 o( ?% p+ \( Y

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figure_stretch函数如下：
function C=figure_stretch(fname,w_scale,h_scale)
% Stretch the figure.
% Usage:
9 ]$ h3 Q3 L; A! M* c9 B% C=figure_stretch(fname,w_scale,h_scale)
% fname        : name of the figure
  K, [8 P2 M) _" D; }% w_scale      : stretch scale in width
/ G$ D' p9 w; |2 \! V/ p* l8 _% h_scale      : stretch scale in hight
% Example:
9 p" M0 j2 Q' B, E% fname = 'frog.bmp';
$ a) N2 j2 W+ p5 E3 o" c% B= B= figure_stretch(fname,1,3);
' S+ c" z$ ~' m( F0 T! M  h% [$ j% figure
, p; Z# v- h. O8 y. z8 J% imshow(B);
% Author :  Haiyang Cui
% EMail  :  ***

A= imread(fname);
; ^- p" U- H$ Z3 M# i[I,J,K]=size(A);
x0=1:J;
y0=1:I;
7 v! T0 b" F) L; C[X0,Y0] = meshgrid(x0,y0);
I1 = floor(I*h_scale);
J1 = floor(J*w_scale);

- U% S# p% B* E7 c0 a0 j2 ^" LR = A(:,:,1);
0 t7 v2 ~. l% v1 [G = A(:,:,2);
B = A(:,:,3);
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%
x = 1:J1;
- E3 H1 T( W# Q6 r. A% X) I) Q0 My = 1:I1;
[X,Y] = meshgrid(x,y);
8 p) Q1 |: ~7 x
X = X*J/J1;
Y = Y*I/I1;
. l% t& J9 Y* W9 [' Z9 aX = double(X);
Y = double(Y);
- V( q5 i$ |0 J. K( DR = double(R);
G = double(G);
B = double(B);
! U" ]$ o, G, R1 |  A9 b, |0 n, l+ F" H! {%
R1 = interp2(X0,Y0,R,X,Y);
G1 = interp2(X0,Y0,G,X,Y);
4 K1 d# B6 W  @, w! v* q2 S5 XB1 = interp2(X0,Y0,B,X,Y);
* d+ K$ v: j1 x  E+ o0 Y5 SC(:,:,1)=uint8(R1);
C(:,:,2)=uint8(G1);
C(:,:,3)=uint8(B1);
- X" d8 H: M+ {$ M  ^5 `end
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CCxiaom

Matlab内图片的拉伸