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changeset 5:084000643ad1

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changed names
author danieleb@code.soundsoftware.ac.uk
date Thu, 16 Jun 2011 13:33:43 +0100
parents e23a23349e31
children e2a029a70df3
files ilot.m lappedorthobasis.m lappedorthoplot.m lotbasis.m lotplot.m
diffstat 5 files changed, 173 insertions(+), 168 deletions(-) [+]
line wrap: on
line diff
--- a/ilot.m	Thu Jun 16 13:16:29 2011 +0100
+++ b/ilot.m	Thu Jun 16 13:33:43 2011 +0100
@@ -81,13 +81,18 @@
 nWindows  = length(wLength);
 sigLength = sum(wLength);
 x         = zeros(sigLength,1);
+p = 1;
 
 % first frame
 g = lappedwindow(wLength(1),tailLength,tailFunc,'first');
 h = invOrthoFun(y(1:wLength(1))); % folded ilot
 C = 1:wLength(1)-tailLength;      % central interval
 Om = wLength(1)-tailLength+(1:tailLength);  %overlapping interval (end)
-hp = invOrthoFun(y(wLength(1)+(1:wLength(2)))); % next folded ilot
+if strcmpi(orthoBasis,'mdct') && p==nWindows-1 % if mdct use idct I
+    hp = idcti(y(sum(wLength(1:end-1))+(1:wLength(end))),'I');
+else
+    hp = invOrthoFun(y(sum(wLength(1:end-1))+(1:wLength(end))));
+end
 x(C) = h(C);
 % unfold
 x(Om) = g(Om).*h(Om) + g(end:-1:end-tailLength+1).*hp(tailLength:-1:1);
@@ -127,5 +132,5 @@
 C  = sum(wLength(1:end-1))+(tailLength+1:wLength(end));
 % unfold
 x(Op) = g(tailLength+(1:tailLength)).*h(1:tailLength) - ...
-        g(tailLength:-1:1).*hm(end:-1:end-tailLength+1);
+    g(tailLength:-1:1).*hm(end:-1:end-tailLength+1);
 x(C) = h(tailLength+1:end);
--- a/lappedorthobasis.m	Thu Jun 16 13:16:29 2011 +0100
+++ /dev/null	Thu Jan 01 00:00:00 1970 +0000
@@ -1,115 +0,0 @@
-function phi = lappedorthobasis(wLength,orthobasis,tailLength,tailFunc)
-%LAPPEDORTHOBASIS Lapped orthogonal basis matrix
-%
-% phi = lappedorthobasis(wLength,orthobasis,tailLength,tailFunc)
-%
-% returns a matrix whose columns contain the atoms of a lapped orhogonal
-% basis function.
-%
-% INPUT:
-% - wLength: vector containing the lengths of the overlapping windows
-% - orthobasis: either a string or a function handle corresponding to an
-% orhogonal transform to be used in each overlapping window. The default
-% is DCT-IV (which is globally referred as MDCT)
-% - tailLength: length of the tail of the overlapping windows. Two
-% consecutive windows overlap in a portion of dimension 2*tailLength. 
-% The maximum tailLength cannot exceed half the length of the smallest 
-% window. 
-% - tailFunc: either a string or a function handle used to define the tails
-% of the overlapping windows. The default is 'sin2' (twicely differentiable
-% sinusoidal).
-%
-% OUTPUT:
-% - phi: matrix containing the lapped orthogonal dictionary.
-%
-% REFERENCE:
-% S. Mallat, A Wavelet Tour of Signal Processing
-%
-% SEE ALSO
-% lappedorthotransform, lappedwindow
-%
-% ----------------------------------------------------------- %
-%  Daniele Barchiesi, daniele.barchiesi@eecs.qmul.ac.uk       %
-%  Centre for Digital Music, Queen Mary University of London  %
-%  Apr. 2011                                                  %
-% ----------------------------------------------------------- %
-%% check inputs & defaults
-error(nargchk(1, 4, nargin, 'struct'));
-if ~exist('tailFunc','var')   || isempty(tailFunc), tailFunc = 'sin2'; end
-if ~exist('tailLength','var') || isempty(tailLength), tailLength = floor(min(wLength)/2); end
-if ~exist('orthobasis','var') || isempty(orthobasis), orthobasis = 'mdct'; end
-
-% select local orthonormal transform
-if ischar(orthobasis)
-    switch orthobasis
-        case 'mdct'
-            basisFun = @(x) dcti(x,'IV');
-        otherwise
-            error('invalid basis function');
-    end
-elseif isa(orthobasis,'function_handle')
-    basisFun = orthobasis;
-else
-    error('invalid basis function');
-end
-
-%% calculate dictionary
-nWindows  = length(wLength);
-sigLength = sum(wLength);                 
-phi       = zeros(sigLength);
-suppLen   = @(p) wLength(p)+2*tailLength;
-
-% first frame
-% generate window
-g = lappedwindow(wLength(1),tailLength,tailFunc,'first');
-% generate local orthogonal matrix
-orthoMat = basisFun(eye(wLength(1)));
-% periodically extend length of basis functions to overlapping regions
-orthoMatExtended = orthomatextend(orthoMat,tailLength,'first');
-% multiply local orthogonal matrix by windowing function
-phi(1:wLength(1)+tailLength,1:wLength(1)) = diag(sparse(g))*orthoMatExtended;
-
-% central frames
-for p=2:nWindows-1
-    % generate window
-    g = lappedwindow(wLength(p),tailLength,tailFunc);
-    % generate local orthogonal matrix
-    orthoMat = basisFun(eye(wLength(p)));
-    % periodically extend length of basis functions to overlapping regions
-    orthoMatExtended = orthomatextend(orthoMat,tailLength);
-    % multiply local orthogonal matrix by windowing function
-    phi(sum(wLength(1:p-1))-tailLength+(1:suppLen(p)),sum(wLength(1:p-1))+(1:wLength(p)))...
-        = diag(sparse(g))*orthoMatExtended;
-end
-
-%last frame
-% generate window
-g = lappedwindow(wLength(end),tailLength,tailFunc,'last');
-% generate local orthogonal matrix
-if strcmpi(orthobasis,'mdct') %if mdct use dct I at last block to avoid artefacts
-    orthoMat = dcti(eye(wLength(end)),'I');
-else
-    orthoMat = basisFun(eye(wLength(end)));
-end
-% periodically extend length of basis functions to overlapping regions
-orthoMatExtended = orthomatextend(orthoMat,tailLength,'last');
-% multiply local orthogonal matrix by windowing function
-phi(sum(wLength(1:end-1))-tailLength+(1:wLength(end)+tailLength),sum(wLength(1:end-1))+(1:wLength(end)))...
-    = diag(sparse(g))*orthoMatExtended;
-
-function orthomatextended = orthomatextend(orthomat,tailLength,special)
-% Periodic extension of local orthonormal basis
-if ~exist('special','var') || isempty(special), special = []; end
-
-if strcmpi(special,'first')
-    % odd symmetry at the end of basis functions
-    orthomatextended = [orthomat; -orthomat(end:-1:end-tailLength+1,:)];
-elseif strcmpi(special,'last')
-    % even symmetry at the beginning of basis functions
-    orthomatextended = [flipud(orthomat(1:tailLength,:)); orthomat];
-else
-    % even symmetry at the beginning and odd symmetry at the end of basis
-    % functions
-    orthomatextended = [flipud(orthomat(1:tailLength,:)); orthomat; ...
-        -orthomat(end:-1:end-tailLength+1,:)];
-end
\ No newline at end of file
--- a/lappedorthoplot.m	Thu Jun 16 13:16:29 2011 +0100
+++ /dev/null	Thu Jan 01 00:00:00 1970 +0000
@@ -1,51 +0,0 @@
-function varargout = lappedorthoplot(y,wLength,Fs)
-%LAPPEDORTHOPLOT plot of the lapped orthogonal transform
-%
-% varargout = lappedorthoplot(y,wLength,timeVec)
-%
-% plots a spectrogram-like visualisation of the lapped orthogonal
-% transform coefficients contained in y
-%
-% INPUT:
-% - y: vector containing the lapped orthogonal transform coefficients
-% - wLength: vector containing the lengths of the overlapping windows
-% - Fs: sampling frequency (default 44100)
-%
-% OUTPUT:
-% - varargout{1}: optionally, the function outputs the matrix containing 
-% the spectrogram-like representation.
-%
-% SEE ALSO
-% lappedorthotransform
-%
-% ----------------------------------------------------------- %
-%  Daniele Barchiesi, daniele.barchiesi@eecs.qmul.ac.uk       %
-%  Centre for Digital Music, Queen Mary University of London  %
-%  Apr. 2011                                                  %
-% ----------------------------------------------------------- %
-nWindows = length(wLength);
-maxLength = max(wLength);
-sigLength = sum(wLength);
-
-if ~exist('Fs','var') || isempty(Fs), Fs = 44100; end
-
-timeVec = linspace(0,sigLength/Fs,10*ceil(sigLength/min(wLength))); 
-
-S = zeros(maxLength,length(timeVec));
-timeSupp  = @(p) floor(wLength(p)*length(timeVec)/sigLength);
-interpFun = @(p,v) interp1(1:wLength(p),abs(v),linspace(1,wLength(p),maxLength))';
-S(:,1:timeSupp(1)) = repmat(interpFun(1,y(1:wLength(1))),1,timeSupp(1));
-for i=2:nWindows
-    S(:,sum(timeSupp(1:i-1))+(1:timeSupp(i))) = ...
-        repmat(interpFun(i,y(sum(wLength(1:i-1))+(1:wLength(i)))),1,timeSupp(i));
-end
-
-SmagdB = mag2db(S);
-if nargout, varargout{1} = SmagdB; end
-
-surf(timeVec,1:maxLength,SmagdB,'EdgeColor','none');
-axis xy; axis tight;
-colormap(jet);
-view(0,90);
-set(gca,'YScale','log');
-title(['l1/l2 = ' num2str(l1overl2(y))])
\ No newline at end of file
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/lotbasis.m	Thu Jun 16 13:33:43 2011 +0100
@@ -0,0 +1,115 @@
+function phi = lotbasis(wLength,orthobasis,tailLength,tailFunc)
+%LAPPEDORTHOBASIS Lapped orthogonal basis matrix
+%
+% phi = lappedorthobasis(wLength,orthobasis,tailLength,tailFunc)
+%
+% returns a matrix whose columns contain the atoms of a lapped orhogonal
+% basis function.
+%
+% INPUT:
+% - wLength: vector containing the lengths of the overlapping windows
+% - orthobasis: either a string or a function handle corresponding to an
+% orhogonal transform to be used in each overlapping window. The default
+% is DCT-IV (which is globally referred as MDCT)
+% - tailLength: length of the tail of the overlapping windows. Two
+% consecutive windows overlap in a portion of dimension 2*tailLength. 
+% The maximum tailLength cannot exceed half the length of the smallest 
+% window. 
+% - tailFunc: either a string or a function handle used to define the tails
+% of the overlapping windows. The default is 'sin2' (twicely differentiable
+% sinusoidal).
+%
+% OUTPUT:
+% - phi: matrix containing the lapped orthogonal dictionary.
+%
+% REFERENCE:
+% S. Mallat, A Wavelet Tour of Signal Processing
+%
+% SEE ALSO
+% lappedorthotransform, lappedwindow
+%
+
+% Author(s): Daniele Barchiesi
+% Copyright QMUL
+% $Revision: 1
+
+%% check inputs & defaults
+error(nargchk(1, 4, nargin, 'struct'));
+if ~exist('tailFunc','var')   || isempty(tailFunc), tailFunc = 'sin2'; end
+if ~exist('tailLength','var') || isempty(tailLength), tailLength = floor(min(wLength)/2); end
+if ~exist('orthobasis','var') || isempty(orthobasis), orthobasis = 'mdct'; end
+
+% select local orthonormal transform
+if ischar(orthobasis)
+    switch orthobasis
+        case 'mdct'
+            basisFun = @(x) dcti(x,'IV');
+        otherwise
+            error('invalid basis function');
+    end
+elseif isa(orthobasis,'function_handle')
+    basisFun = orthobasis;
+else
+    error('invalid basis function');
+end
+
+%% calculate dictionary
+nWindows  = length(wLength);
+sigLength = sum(wLength);                 
+phi       = zeros(sigLength);
+suppLen   = @(p) wLength(p)+2*tailLength;
+
+% first frame
+% generate window
+g = lappedwindow(wLength(1),tailLength,tailFunc,'first');
+% generate local orthogonal matrix
+orthoMat = basisFun(eye(wLength(1)));
+% periodically extend length of basis functions to overlapping regions
+orthoMatExtended = orthomatextend(orthoMat,tailLength,'first');
+% multiply local orthogonal matrix by windowing function
+phi(1:wLength(1)+tailLength,1:wLength(1)) = diag(sparse(g))*orthoMatExtended;
+
+% central frames
+for p=2:nWindows-1
+    % generate window
+    g = lappedwindow(wLength(p),tailLength,tailFunc);
+    % generate local orthogonal matrix
+    orthoMat = basisFun(eye(wLength(p)));
+    % periodically extend length of basis functions to overlapping regions
+    orthoMatExtended = orthomatextend(orthoMat,tailLength);
+    % multiply local orthogonal matrix by windowing function
+    phi(sum(wLength(1:p-1))-tailLength+(1:suppLen(p)),sum(wLength(1:p-1))+(1:wLength(p)))...
+        = diag(sparse(g))*orthoMatExtended;
+end
+
+%last frame
+% generate window
+g = lappedwindow(wLength(end),tailLength,tailFunc,'last');
+% generate local orthogonal matrix
+if strcmpi(orthobasis,'mdct') %if mdct use dct I at last block to avoid artefacts
+    orthoMat = dcti(eye(wLength(end)),'I');
+else
+    orthoMat = basisFun(eye(wLength(end)));
+end
+% periodically extend length of basis functions to overlapping regions
+orthoMatExtended = orthomatextend(orthoMat,tailLength,'last');
+% multiply local orthogonal matrix by windowing function
+phi(sum(wLength(1:end-1))-tailLength+(1:wLength(end)+tailLength),sum(wLength(1:end-1))+(1:wLength(end)))...
+    = diag(sparse(g))*orthoMatExtended;
+
+function orthomatextended = orthomatextend(orthomat,tailLength,special)
+% Periodic extension of local orthonormal basis
+if ~exist('special','var') || isempty(special), special = []; end
+
+if strcmpi(special,'first')
+    % odd symmetry at the end of basis functions
+    orthomatextended = [orthomat; -orthomat(end:-1:end-tailLength+1,:)];
+elseif strcmpi(special,'last')
+    % even symmetry at the beginning of basis functions
+    orthomatextended = [flipud(orthomat(1:tailLength,:)); orthomat];
+else
+    % even symmetry at the beginning and odd symmetry at the end of basis
+    % functions
+    orthomatextended = [flipud(orthomat(1:tailLength,:)); orthomat; ...
+        -orthomat(end:-1:end-tailLength+1,:)];
+end
\ No newline at end of file
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/lotplot.m	Thu Jun 16 13:33:43 2011 +0100
@@ -0,0 +1,51 @@
+function varargout = lappedorthoplot(y,wLength,Fs)
+%LAPPEDORTHOPLOT plot of the lapped orthogonal transform
+%
+% varargout = lappedorthoplot(y,wLength,timeVec)
+%
+% plots a spectrogram-like visualisation of the lapped orthogonal
+% transform coefficients contained in y
+%
+% INPUT:
+% - y: vector containing the lapped orthogonal transform coefficients
+% - wLength: vector containing the lengths of the overlapping windows
+% - Fs: sampling frequency (default 44100)
+%
+% OUTPUT:
+% - varargout{1}: optionally, the function outputs the matrix containing 
+% the spectrogram-like representation.
+%
+% SEE ALSO
+% lappedorthotransform
+%
+% ----------------------------------------------------------- %
+%  Daniele Barchiesi, daniele.barchiesi@eecs.qmul.ac.uk       %
+%  Centre for Digital Music, Queen Mary University of London  %
+%  Apr. 2011                                                  %
+% ----------------------------------------------------------- %
+nWindows = length(wLength);
+maxLength = max(wLength);
+sigLength = sum(wLength);
+
+if ~exist('Fs','var') || isempty(Fs), Fs = 44100; end
+
+timeVec = linspace(0,sigLength/Fs,10*ceil(sigLength/min(wLength))); 
+
+S = zeros(maxLength,length(timeVec));
+timeSupp  = @(p) floor(wLength(p)*length(timeVec)/sigLength);
+interpFun = @(p,v) interp1(1:wLength(p),abs(v),linspace(1,wLength(p),maxLength))';
+S(:,1:timeSupp(1)) = repmat(interpFun(1,y(1:wLength(1))),1,timeSupp(1));
+for i=2:nWindows
+    S(:,sum(timeSupp(1:i-1))+(1:timeSupp(i))) = ...
+        repmat(interpFun(i,y(sum(wLength(1:i-1))+(1:wLength(i)))),1,timeSupp(i));
+end
+
+SmagdB = mag2db(S);
+if nargout, varargout{1} = SmagdB; end
+
+surf(timeVec,1:maxLength,SmagdB,'EdgeColor','none');
+axis xy; axis tight;
+colormap(jet);
+view(0,90);
+set(gca,'YScale','log');
+title(['l1/l2 = ' num2str(l1overl2(y))])
\ No newline at end of file