📄 gfcreatefilterf2.html
字号:
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/REC-html40/loose.dtd"><html><head> <title>Description of gfcreatefilterf2</title> <meta name="keywords" content="gfcreatefilterf2"> <meta name="description" content="GFCREATEFILTERF2 Create normalized 2-D Gabor filter in the frequency domain."> <meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1"> <meta name="generator" content="m2html © 2003 Guillaume Flandin"> <meta name="robots" content="index, follow"> <link type="text/css" rel="stylesheet" href="../m2html.css"></head><body><a name="_top"></a><div><a href="../index.html">Home</a> > <a href="index.html">gabortb-v0.4.1</a> > gfcreatefilterf2.m</div><!--<table width="100%"><tr><td align="left"><a href="../index.html"><img alt="<" border="0" src="../left.png"> Master index</a></td><td align="right"><a href="index.html">Index for gabortb-v0.4.1 <img alt=">" border="0" src="../right.png"></a></td></tr></table>--><h1>gfcreatefilterf2</h1><h2><a name="_name"></a>PURPOSE <a href="#_top"><img alt="^" border="0" src="../up.png"></a></h2><div class="box"><strong>GFCREATEFILTERF2 Create normalized 2-D Gabor filter in the frequency domain.</strong></div><h2><a name="_synopsis"></a>SYNOPSIS <a href="#_top"><img alt="^" border="0" src="../up.png"></a></h2><div class="box"><strong>function [g]=gfcreatefilterf2(f0, theta, gamma, eta, N,varargin) </strong></div><h2><a name="_description"></a>DESCRIPTION <a href="#_top"><img alt="^" border="0" src="../up.png"></a></h2><div class="fragment"><pre class="comment">GFCREATEFILTERF2 Create normalized 2-D Gabor filter in the frequency domain. [G] = GFCREATEFILTERF2(F0,THETA,GAMMA,ETA,N,...) creates a two-dimensional normalized Gabor filter G with central frequency F0, orientation THETA, normalized width GAMMA along the wave orientation, normalized width ETA orthogonal to wave orientation, and size N. Also, a two element vector N = [NX NY] can be used to specify the size. G = GFCREATEFILTERF2(...,'PF',PF) determines that at least P percent of the Gaussian envelope of the filter must be included in the filter in frequency domain. For default, PF=0.998. G = GFCREATEFILTERF2(...,'PT',PT) determines that at least P percent of the Gaussian envelope of the filter must be included in the filter in spatial domain. For default, PT=0.998. Examples See also <a href="gfcreatefilter2.html" class="code" title="function [g]=gfcreatefilter2(f0,theta,gamma,eta,n,varargin)">GFCREATEFILTER2</a>, <a href="gfcheckfilter2.html" class="code" title="function gfcheckfilter2(f0,theta,gamma,eta,n,pt,pf)">GFCHECKFILTER2</a>, <a href="gfcreatefilterf.html" class="code" title="function [g]=gfcreatefilterf(f0,gamma,N,varargin)">GFCREATEFILTERF</a>. References: [1] Kamarainen, J.-K., Kyrki, V., Kalviainen, H., Gabor Features for Invariant Object Recognition, Research report 79, Department of Information Technology, Lappeenranta University of Technology Author(s): Joni Kamarainen <Joni.Kamarainen@lut.fi> Ville Kyrki <Ville.Kyrki@lut.fi> Copyright: The Gabor Features in Signal and Image Processing Toolbox is Copyright (C) 2000 by Joni Kamarainen and Ville Kyrki. $Name: $ $Revision: 1.6 $ $Date: 2003-02-23 16:27:44 $</pre></div><!-- crossreference --><h2><a name="_cross"></a>CROSS-REFERENCE INFORMATION <a href="#_top"><img alt="^" border="0" src="../up.png"></a></h2>This function calls:<ul style="list-style-image:url(../matlabicon.gif)"><li><a href="gfcheckfilter2.html" class="code" title="function gfcheckfilter2(f0,theta,gamma,eta,n,pt,pf)">gfcheckfilter2</a> GFCHECKFILTER2 Check 2-d filter parameters.</li></ul>This function is called by:<ul style="list-style-image:url(../matlabicon.gif)"><li><a href="gfcreateinformationdiagram2.html" class="code" title="function [resps,freqs,orients] = gfcreateinformationdiagram2(img_, f0_,theta_, gamma_,eta_, varargin);">gfcreateinformationdiagram2</a> GFCREATEINFORMATIONDIAGRAM2 Information diagram of 2-D signal</li><li><a href="gfdemo02.html" class="code" title="function [] = gfdemo02;">gfdemo02</a> GFDEMO02 Demonstrate 2-D Gabor functionality</li></ul><!-- crossreference --><h2><a name="_source"></a>SOURCE CODE <a href="#_top"><img alt="^" border="0" src="../up.png"></a></h2><div class="fragment"><pre>0001 <span class="comment">%GFCREATEFILTERF2 Create normalized 2-D Gabor filter in the frequency domain.</span>0002 <span class="comment">%</span>0003 <span class="comment">% [G] = GFCREATEFILTERF2(F0,THETA,GAMMA,ETA,N,...) creates a</span>0004 <span class="comment">% two-dimensional normalized Gabor filter G with central</span>0005 <span class="comment">% frequency F0, orientation THETA, normalized width GAMMA along</span>0006 <span class="comment">% the wave orientation, normalized width ETA orthogonal to wave</span>0007 <span class="comment">% orientation, and size N. Also, a two element vector N = [NX</span>0008 <span class="comment">% NY] can be used to specify the size.</span>0009 <span class="comment">%</span>0010 <span class="comment">% G = GFCREATEFILTERF2(...,'PF',PF) determines that at least</span>0011 <span class="comment">% P percent of the Gaussian envelope of the filter must be</span>0012 <span class="comment">% included in the filter in frequency domain. For default,</span>0013 <span class="comment">% PF=0.998.</span>0014 <span class="comment">%</span>0015 <span class="comment">% G = GFCREATEFILTERF2(...,'PT',PT) determines that at least</span>0016 <span class="comment">% P percent of the Gaussian envelope of the filter must be</span>0017 <span class="comment">% included in the filter in spatial domain. For default,</span>0018 <span class="comment">% PT=0.998.</span>0019 <span class="comment">%</span>0020 <span class="comment">% Examples</span>0021 <span class="comment">%</span>0022 <span class="comment">% See also GFCREATEFILTER2, GFCHECKFILTER2, GFCREATEFILTERF.</span>0023 <span class="comment">%</span>0024 <span class="comment">% References:</span>0025 <span class="comment">% [1] Kamarainen, J.-K., Kyrki, V., Kalviainen, H., Gabor</span>0026 <span class="comment">% Features for Invariant Object Recognition, Research</span>0027 <span class="comment">% report 79, Department of Information Technology,</span>0028 <span class="comment">% Lappeenranta University of Technology</span>0029 <span class="comment">%</span>0030 <span class="comment">% Author(s):</span>0031 <span class="comment">% Joni Kamarainen <Joni.Kamarainen@lut.fi></span>0032 <span class="comment">% Ville Kyrki <Ville.Kyrki@lut.fi></span>0033 <span class="comment">%</span>0034 <span class="comment">% Copyright:</span>0035 <span class="comment">%</span>0036 <span class="comment">% The Gabor Features in Signal and Image Processing Toolbox is</span>0037 <span class="comment">% Copyright (C) 2000 by Joni Kamarainen and Ville Kyrki.</span>0038 <span class="comment">%</span>0039 <span class="comment">%</span>0040 <span class="comment">% $Name: $ $Revision: 1.6 $ $Date: 2003-02-23 16:27:44 $</span>0041 <span class="comment">%</span>0042 <a name="_sub0" href="#_subfunctions" class="code">function [g]=gfcreatefilterf2(f0, theta, gamma, eta, N,varargin)</a>0043 0044 <span class="comment">%</span>0045 <span class="comment">% Setting default values</span>0046 alpha = f0/gamma;0047 beta = f0/eta;0048 PT = 0.998;0049 PF = 0.998;0050 0051 <span class="comment">%</span>0052 <span class="comment">% Parameter parsing</span>0053 <span class="keyword">if</span> mod(length(varargin),2)>0,0054 error(<span class="string">'Each parameter must be given a value.'</span>);0055 <span class="keyword">end</span>;0056 0057 currentarg = 1;0058 <span class="keyword">while</span> (length(varargin) > currentarg)0059 [param,value]=deal(varargin{currentarg:currentarg+1});0060 <span class="keyword">switch</span> lower(param)0061 <span class="keyword">case</span> <span class="string">'pt'</span>0062 PT = value;0063 <span class="keyword">case</span> <span class="string">'pf'</span>0064 PF = value;0065 <span class="keyword">otherwise</span>0066 error([<span class="string">'Unknown parameter '''</span> param <span class="string">'''.'</span>]);0067 <span class="keyword">end</span>;0068 currentarg=currentarg+2;0069 <span class="keyword">end</span>;0070 0071 <span class="comment">% filter size</span>0072 <span class="keyword">if</span> length(N)>1,0073 Nx=N(1);0074 Ny=N(2);0075 <span class="keyword">else</span>0076 Nx=N;0077 Ny=N;0078 <span class="keyword">end</span>;0079 0080 <span class="comment">% Check filter constraints</span>0081 <a href="gfcheckfilter2.html" class="code" title="function gfcheckfilter2(f0,theta,gamma,eta,n,pt,pf)">gfcheckfilter2</a>(f0,theta,gamma,eta,N,PT,PF);0082 0083 <span class="comment">% Check if save file exists and load it</span>0084 <span class="keyword">if</span> (isunix)0085 [status userName] = unix(<span class="string">'whoami'</span>);0086 <span class="keyword">if</span> (size(userName,2) > 1)0087 useTempFiles = 1;0088 userName = userName(1,1:end-1);<span class="comment">% remove line change</span>0089 temporarySaveFileName = <span class="keyword">...</span>0090 fullfile(tempdir,[<span class="string">'gf-'</span> userName <span class="string">'-'</span> <span class="keyword">...</span>0091 num2str(f0) <span class="string">'-'</span> num2str(theta) <span class="keyword">...</span>0092 <span class="string">'-'</span> num2str(gamma) <span class="string">'-'</span> num2str(eta) <span class="string">'-'</span> num2str(Nx) <span class="keyword">...</span>0093 <span class="string">'-'</span> num2str(Ny) <span class="string">'-'</span> num2str(PT) <span class="string">'-'</span> num2str(PF) <span class="string">'.mat'</span>]);0094 <span class="keyword">else</span>0095 useTempFiles = 0;0096 <span class="keyword">end</span>;0097 <span class="keyword">else</span>0098 [status userName] = unix(<span class="string">'echo %USERNAME%'</span>);0099 <span class="keyword">if</span> (size(userName,2) > 1)0100 useTempFiles = 1;0101 userName = userName(1,1:end-1);<span class="comment">% remove line change</span>0102 temporarySaveFileName = <span class="keyword">...</span>0103 fullfile(tempdir,[<span class="string">'gf-'</span> userName <span class="string">'-'</span> <span class="keyword">...</span>0104 num2str(f0) <span class="string">'-'</span> num2str(theta) <span class="keyword">...</span>0105 <span class="string">'-'</span> num2str(gamma) <span class="string">'-'</span> num2str(eta) <span class="string">'-'</span> num2str(Nx) <span class="keyword">...</span>0106 <span class="string">'-'</span> num2str(Ny) <span class="string">'-'</span> num2str(PT) <span class="string">'-'</span> num2str(PF) <span class="string">'.mat'</span>])0107 <span class="keyword">else</span>0108 useTempFiles = 0;0109 <span class="keyword">end</span>;0110 <span class="keyword">end</span>;0111 0112 <span class="comment">% THIS WAS OLD WAY BUT IT DIDNT WORK IN WINDOWS AND SUFFERED USMASKS BETWEEN</span>0113 <span class="comment">% DIFFERENT USERS IN THE SAME SYSTEM</span>0114 <span class="comment">%temporarySaveFileName = fullfile</span>0115 <span class="comment">%temporarySaveFileName = ['/tmp/gffilter-' num2str(f0) '-' num2str(theta) ...</span>0116 <span class="comment">% '-' num2str(gamma) '-' num2str(eta) '-' num2str(Nx) ...</span>0117 <span class="comment">% '-' num2str(Ny) '-' num2str(PT) '-' num2str(PF) '.mat']</span>0118 0119 <span class="keyword">if</span> (useTempFiles==1 & exist(temporarySaveFileName) == 2)0120 load(temporarySaveFileName);0121 <span class="keyword">else</span>0122 g = zeros(Ny,Nx);0123 0124 <span class="comment">% SOLUTION 1: easy to understand, but may need whole lotta memory</span>0125 nx = -Nx:1:Nx;0126 ny = -Ny:1:Ny;0127 u = nx/Nx; <span class="comment">% frequencies that bank contains</span>0128 v = ny/Ny;0129 [U,V]=meshgrid(u,v);0130 gf = exp(-pi^2*( (U*sin(theta)-V*cos(theta)).^2/beta^2 + <span class="keyword">...</span>0131 (U*cos(theta)+V*sin(theta)-f0).^2/alpha^2 ));0132 0133 <span class="comment">% Calculating the filter using aliasing</span>0134 g = g+gf(1:Ny,1:Nx); <span class="comment">% A_1</span>0135 g = g+gf(1:Ny,(Nx+1):(2*Nx)); <span class="comment">% A_2</span>0136 g = g+gf((Ny+1):(2*Ny),1:Nx); <span class="comment">% A_3</span>0137 g = g+gf((Ny+1):(2*Ny),(Nx+1):(2*Nx)); <span class="comment">% A_4</span>0138 0139 <span class="keyword">if</span> (useTempFiles) <span class="comment">% save this filter</span>0140 save(temporarySaveFileName, <span class="string">'g'</span>);0141 <span class="keyword">end</span>;0142 <span class="keyword">end</span>;0143 0144 0145 0146 0147 0148 0149 0150 0151</pre></div><hr><address>Generated on Fri 23-Nov-2007 14:52:42 by <strong><a href="http://www.artefact.tk/software/matlab/m2html/">m2html</a></strong> © 2003</address></body></html>⌨️ 快捷键说明
复制代码
Ctrl + C
搜索代码
Ctrl + F
全屏模式
F11
切换主题
Ctrl + Shift + D
显示快捷键
?
增大字号
Ctrl + =
减小字号
Ctrl + -