Matlab内图片的拉伸

piday123

$ i2 F- }  J2 @. rMatlab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。
* n- a3 `  u+ O# U- P; X! e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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; g" Y. U- b: d: u* Efname = 'frog.bmp';
A=imread(fname);
imshow(A);
set(gcf,'position',[100 100 400 800]);
" X. S% D) s# a7 s- f( j4 i, J/ o; N效果如下:
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3 D4 |9 v: R; O- ]4 t, ~' d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。
或者写个函数

; ~  l9 _  M$ ?B= figure_stretch(A,1,3);
8 \3 G1 f. d. S" \* E0 z. Ufigure
imshow(B);
set(gcf,'position',[100 100 400 800]);
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效果如下:
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figure_stretch函数如下：
) k7 ?% T4 P' W, `7 rfunction C=figure_stretch(fname,w_scale,h_scale)
$ @/ ]0 h9 B3 C% Stretch the figure.
% Usage:
% C=figure_stretch(fname,w_scale,h_scale)
* G9 D" H% @- K/ s$ K3 G+ p, P% fname        : name of the figure
- ^; W% @: O$ R* g1 T% w_scale      : stretch scale in width
3 j7 v; x! z3 Y" v, Z; t& X% h_scale      : stretch scale in hight
% Example:
  s8 z: [1 V( n6 h+ y: n( H% fname = 'frog.bmp';
% B= B= figure_stretch(fname,1,3);
% figure
* W+ R5 T% s" c% [6 A% imshow(B);
+ M0 l* ~: I/ V% Author :  Haiyang Cui
% EMail  :  ***
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A= imread(fname);
[I,J,K]=size(A);
# e% E! i* {( g, Y- ~- ^% e* t( qx0=1:J;
y0=1:I;
[X0,Y0] = meshgrid(x0,y0);
0 V5 ?3 e% Y8 i/ JI1 = floor(I*h_scale);
J1 = floor(J*w_scale);
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' `+ ]% w3 c7 f6 vR = A(:,:,1);
G = A(:,:,2);
: ~$ n/ ^: Z  k9 B% gB = A(:,:,3);
; K9 {: {  }* B  I; Y2 [2 E
%
# Z; K' f' _% R, X: _x = 1:J1;
y = 1:I1;
# w& A7 H/ n- @: I( N  h0 `0 V& l( p$ D[X,Y] = meshgrid(x,y);
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X = X*J/J1;
Y = Y*I/I1;
4 v5 L+ F8 l6 O) M$ Z; C" E$ T" {X = double(X);
Y = double(Y);
R = double(R);
; m5 A4 ?+ M6 P. g4 T8 S9 lG = double(G);
B = double(B);
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# ~1 c8 E3 u0 o0 i0 Z5 sR1 = interp2(X0,Y0,R,X,Y);
G1 = interp2(X0,Y0,G,X,Y);
) S& k: |1 r0 vB1 = interp2(X0,Y0,B,X,Y);
  R" H2 J6 D% i, Y/ RC(:,:,1)=uint8(R1);
% l/ ^8 t. j" {# IC(:,:,2)=uint8(G1);
5 h+ d/ t$ i8 [+ q& ?' UC(:,:,3)=uint8(B1);
" ]7 D! c/ h, {9 b" mend
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Matlab内图片的拉伸