diff options
Diffstat (limited to 'SD-VBS/common/toolbox/MultiNcut/doog2.m')
-rwxr-xr-x | SD-VBS/common/toolbox/MultiNcut/doog2.m | 38 |
1 files changed, 38 insertions, 0 deletions
diff --git a/SD-VBS/common/toolbox/MultiNcut/doog2.m b/SD-VBS/common/toolbox/MultiNcut/doog2.m new file mode 100755 index 0000000..a0511cb --- /dev/null +++ b/SD-VBS/common/toolbox/MultiNcut/doog2.m | |||
@@ -0,0 +1,38 @@ | |||
1 | function G=doog2(sig,r,th,N); | ||
2 | % G=doog2(sig,r,th,N); | ||
3 | % Make difference of offset gaussians kernel | ||
4 | % theta is in degrees | ||
5 | % (see Malik & Perona, J. Opt. Soc. Amer., 1990) | ||
6 | % | ||
7 | % Example: | ||
8 | % >> imagesc(doog2(1,12,0,64,1)) | ||
9 | % >> colormap(gray) | ||
10 | |||
11 | % by Serge Belongie | ||
12 | |||
13 | no_pts=N; % no. of points in x,y grid | ||
14 | |||
15 | [x,y]=meshgrid(-(N/2)+1/2:(N/2)-1/2,-(N/2)+1/2:(N/2)-1/2); | ||
16 | |||
17 | phi=pi*th/180; | ||
18 | sigy=sig; | ||
19 | sigx=r*sig; | ||
20 | R=[cos(phi) -sin(phi); sin(phi) cos(phi)]; | ||
21 | C=R*diag([sigx,sigy])*R'; | ||
22 | |||
23 | X=[x(:) y(:)]; | ||
24 | |||
25 | Gb=gaussian(X,[0 0]',C); | ||
26 | Gb=reshape(Gb,N,N); | ||
27 | |||
28 | m=R*[0 sig]'; | ||
29 | Ga=gaussian(X,m,C); | ||
30 | Ga=reshape(Ga,N,N); | ||
31 | Gc=rot90(Ga,2); | ||
32 | |||
33 | a=-1; | ||
34 | b=2; | ||
35 | c=-1; | ||
36 | |||
37 | G = a*Ga + b*Gb + c*Gc; | ||
38 | |||