source: trunk/src/transform_field/ima_noise_rms.m @ 924

Last change on this file since 924 was 924, checked in by g7moreau, 5 years ago
  • Update Copyright Copyright 2008-2016, LEGI UMR 5519 / CNRS UGA G-INP, Grenoble, France
File size: 3.1 KB
Line 
1% 'ima_noise_rms': gives the variance of relative noise by difference to the
2% filered image in ppm (part per million) (for grey scale image)
3%------------------------------------------------------------------------
4%%%%  Use the general syntax for transform fields with a single input and parameters %%%%
5% OUTPUT:
6% DataOut:   output field structure
7%
8%INPUT:
9% DataIn:  input field structure
10% Param: matlab structure whose field Param.TransformInput contains the filter parameters
11
12%=======================================================================
13% Copyright 2008-2016, LEGI UMR 5519 / CNRS UGA G-INP, Grenoble, France
14%   http://www.legi.grenoble-inp.fr
15%   Joel.Sommeria - Joel.Sommeria (A) legi.cnrs.fr
16%
17%     This file is part of the toolbox UVMAT.
18%
19%     UVMAT is free software; you can redistribute it and/or modify
20%     it under the terms of the GNU General Public License as published
21%     by the Free Software Foundation; either version 2 of the license,
22%     or (at your option) any later version.
23%
24%     UVMAT is distributed in the hope that it will be useful,
25%     but WITHOUT ANY WARRANTY; without even the implied warranty of
26%     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
27%     GNU General Public License (see LICENSE.txt) for more details.
28%=======================================================================
29
30function DataOut=ima_noise_rms(DataIn,Param)
31
32%% request input parameters
33if isfield(DataIn,'Action') && isfield(DataIn.Action,'RUN') && isequal(DataIn.Action.RUN,0)
34    prompt = {'npx';'npy'};
35    dlg_title = 'get the filter size in x and y';
36    num_lines= 2;
37    def     = { '20';'20'};
38    if isfield(Param,'TransformInput')&&isfield(Param.TransformInput,'FilterBoxSize_x')&&...
39            isfield(Param.TransformInput,'FilterBoxSize_y')
40        def={num2str(Param.TransformInput.FilterBoxSize_x);num2str(Param.TransformInput.FilterBoxSize_y)};
41    end
42    answer = inputdlg(prompt,dlg_title,num_lines,def);
43    DataOut.TransformInput.FilterBoxSize_x=str2num(answer{1}); %size of the filtering window
44    DataOut.TransformInput.FilterBoxSize_y=str2num(answer{2}); %size of the filtering window
45    return
46end
47
48DataOut=DataIn; %default
49
50%definition of the cos shape matrix filter
51ix=[1/2-Param.TransformInput.FilterBoxSize_x/2:-1/2+Param.TransformInput.FilterBoxSize_x/2];%
52iy=[1/2-Param.TransformInput.FilterBoxSize_y/2:-1/2+Param.TransformInput.FilterBoxSize_y/2];%
53%del=np/3;
54%fct=exp(-(ix/del).^2);
55fct2_x=cos(ix/((Param.TransformInput.FilterBoxSize_x-1)/2)*pi/2);
56fct2_y=cos(iy/((Param.TransformInput.FilterBoxSize_y-1)/2)*pi/2);
57%Mfiltre=(ones(5,5)/5^2);
58Mfiltre=fct2_y'*fct2_x;
59Mfiltre=Mfiltre/(sum(sum(Mfiltre)));%normalize filter
60
61Atype=class(DataIn.A);% detect integer 8 or 16 bits
62B=filter2(Mfiltre,DataIn.A);
63B(B==0)=1; %set to 1 the zero values
64C=(double(DataIn.A)-B)./B;
65C=filter2(Mfiltre,C.*C);% take variance  integrated in the filtering area
66C=1000000*sqrt(C); % take the root and *10^6 to get an image with integer values (parts per million)
67DataOut.A=feval(Atype,C);%transform to the initial image format
68   
69
70 
Note: See TracBrowser for help on using the repository browser.