diff --git a/Virtual Sensing/Remote Microphone Technique/MATLAB/Functions/obsFiltTD.m b/Virtual Sensing/Remote Microphone Technique/MATLAB/Functions/obsFiltTD.m
index 09a53a42a368f7482eadcaa05b4ac3afa0bad836..117a978d4954f57ebca443d5d753d82c8cd3b763 100644
--- a/Virtual Sensing/Remote Microphone Technique/MATLAB/Functions/obsFiltTD.m
+++ b/Virtual Sensing/Remote Microphone Technique/MATLAB/Functions/obsFiltTD.m
@@ -3,7 +3,7 @@
% Author: Achilles Kappis
% e-mail: axilleaz@protonmail.com
%
-% Date: 12/09/2024 (DD/MM/YYYY)
+% Date: 13/09/2024 (DD/MM/YYYY)
%
% Copyright: MIT
% --------------------------------------------------
@@ -37,14 +37,27 @@
% delay [numeric] (Optional): The delay to be added to the virtual
% microphone signals, effectively implementing
% the delayed Remote Microphone Technique. This
-% must be a real non-negative scalar less than
+% can be either a scalar, in which case the
+% same delay is applied to all virtual
+% microphone signals, or a vector with each
+% element holding the delay for each virtual
+% microphone signal respectively. The delays
+% must be real non-negative values less than
% or equal to I, the length of the virtual
-% microphone signals. [Default: 0].
+% microphone signals. If "fs" is provided,
+% these values correspond to seconds otherwise
+% they are in samples and must be integer.
+% [Default: 0].
+%
+% fs [numeric] (Optional): The sampling frequency. If this value is given,
+% the delay is treated as being in seconds,
+% otherwise it is in samples. This argument must
+% be a positive real integer.
%
% --------------------------------------------------
% Output
%
-% O [numeric]: The observation filters. This is an firLenxNxMxJ array.
+% O [numeric]: The observation filters. This is an NxfirLenxMxJ array.
%
% Rme [numeric]: The cross-correlation matrices between the monitoring and
% virtual microphone signals. This is an filtLenxMxNxJ
@@ -78,10 +91,13 @@
% can be used directly with either "Ovec" or "Oopt"
% arguments to perform the filtering/estimation.
%
-% Omean [numeric]: The observation filters averaged over the trials/sound
-% field realisations. This is an NxMxfirLen array.
+% Omean [numeric]: The observation filters calculated with the correlation
+% matrices RmeMtx and RmmMtx averaged over the
+% trials/sound field realisations (these are the
+% "RmeMtxMean" and "RmmMtxMean" output arguments). This is
+% an NxfirLenxM array.
%
-% Rmemean [numeric]: The cross-correlation matrices between the monitoring
+% RmeMean [numeric]: The cross-correlation matrices between the monitoring
% and virtual microphone signals averaged over the
% trials/sound field realisations. This is an
% NxMxfirLen array.
@@ -94,10 +110,11 @@
% Oopt [numeric]: This is a matrix with the observation filters
% stacked/vectorised, so that they can be applied to a
% stacked/vectorised monitoring microphone measurements
-% vector, averaged over the trials/sound field
-% realisations. The dimensions of this matrix are
-% NxTotFiltLen. These filters are denoted "optimal" since
-% they are averaged over many realisations (if J > 1).
+% vector, calculated with the correlation matrices RmeMtx
+% and RmmMtx averaged over all trials/sound field
+% realisations (the "RmeMtxMean" and "RmmMtxMean" output
+% arguments). The dimensions of this matrix are
+% NxTotFiltLen.
%
% RmeMtxMean [numeric]: This is the matrix with the cross-correlation
% vectors between the monitoring and virtual
@@ -119,11 +136,11 @@
% Stephen J. Elliott and Jordan Cheer.
%
% --------------------------------------------------
-function [O, Rme, Rmm, Ovec, RmeMtx, RmmMtx, mMtx, Omean, RmeMean, RmmMean, Oopt, RmeMtxMean, RmmMtxMean] = obsFiltTD(e, m, beta, filtLen, delay)
+function [O, Rme, Rmm, Ovec, RmeMtx, RmmMtx, mMtx, Omean, RmeMean, RmmMean, Oopt, RmeMtxMean, RmmMtxMean] = obsFiltTD(e, m, beta, filtLen, delay, fs)
% ====================================================
% Check for number of arguments
% ====================================================
- narginchk(2, 5);
+ narginchk(2, 6);
nargoutchk(0, 13);
% ====================================================
@@ -135,24 +152,50 @@ function [O, Rme, Rmm, Ovec, RmeMtx, RmmMtx, mMtx, Omean, RmeMean, RmmMean, Oopt
% Validate optional arguments
if nargin > 2 && ~isempty(beta)
- validateattributes(beta, "numeric", {'scalar', 'nonnegative', 'nonnan', 'nonempty', 'finite'}, mfilename, "Regularisation factor", 3);
+ validateattributes(beta, "numeric", {'scalar', 'nonnegative', 'nonnan', 'nonempty', 'finite', 'real'}, mfilename, "Regularisation factor", 3);
else
beta = 0;
end
if nargin > 3 && ~isempty(filtLen)
- validateattributes(filtLen, "numeric", {'scalar', 'positive', 'nonnan', 'nonempty', 'finite', '<=', size(m, 1)}, mfilename, "Length of observation filters", 4);
+ validateattributes(filtLen, "numeric", {'scalar', 'positive', 'nonnan', 'real', 'nonempty', 'finite', '<=', size(m, 1)}, mfilename, "Length of observation filters", 4);
else
filtLen = size(m, 2);
end
if nargin > 4 && ~isempty(delay)
- validateattributes(delay, "numeric", {'scalar', 'nonnegative', 'nonnan', 'finite', 'nonempty', '<=', size(e, 1)}, mfilename, "Delay to be added to virtual microphone signals to implement the delayed Remote Microphone Technique", 5);
+ validateattributes(delay, "numeric", {'vector', 'nonnegative', 'nonnan', 'finite', 'real', 'nonempty', '<=', size(e, 1)}, mfilename, "Delay to be added to virtual microphone signals to implement the delayed Remote Microphone Technique", 5);
+
+ if isscalar(delay)
+ delay = delay * ones(size(e, 2), 1);
+ elseif length(delay) ~= size(e, 2)
+ error("The 'delay' argument must be either a scalar, or a vector with number of elements equal to the number of virtual microphone signals.");
+ end
else
- delay = 0;
+ delay = zeros(size(e, 2), 1);
+ end
+
+ if nargin > 5 && ~isempty(fs)
+ validateattributes(fs, "numeric", {'scalar', 'integer', 'positive', 'nonnan', 'nonempty', 'finite', 'real'}, mfilename, "The sampling frequency", 6);
+ else
+ fs = [];
end
+ % ====================================================
+ % Pre-process data
+ % ====================================================
+ % Delay the virtual microphone signals
+ if isempty(fs)
+ for jIdx = size(e, 3):-1:1
+ e(:, :, jIdx) = delayseq(e(:, :, jIdx), delay);
+ end
+ else
+ for jIdx = size(e, 3):-1:1
+ e(:, :, jIdx) = delayseq(e(:, :, jIdx), delay, fs);
+ end
+ end
+
% ====================================================
% Calculate cross- and auto-correlation matrices
% ====================================================
@@ -165,7 +208,7 @@ function [O, Rme, Rmm, Ovec, RmeMtx, RmmMtx, mMtx, Omean, RmeMean, RmmMean, Oopt
[corr, lags] = xcorr(m(:, mIdx, jIdx), e(:, eIdx, jIdx));
lIdx = find(lags == 0);
- Rme(:, mIdx, eIdx, jIdx) = corr(delay + lIdx:-1:lIdx-filtLen + 1);
+ Rme(:, mIdx, eIdx, jIdx) = corr(lIdx:-1:lIdx-filtLen + 1);
end
% Go through the monitoring microphones to calculate the monitoring microphone correlation matrices
@@ -215,9 +258,17 @@ function [O, Rme, Rmm, Ovec, RmeMtx, RmmMtx, mMtx, Omean, RmeMean, RmmMean, Oopt
mMtx = reshape(m, prod(size(m, [1, 2])), size(m, 3));
end
- % Mean observation over trials/sound field realisations
+ % Observation filter calculated with the mean Rme and Rmm over the trials/sound field realisation
if nargout > 7
- Omean = mean(O, 4);
+ % Average the RmeMtx and RmmMtx matrices
+ RmeMtxMean = mean(RmeMtx, 3);
+ RmmMtxMean = mean(RmmMtx, 3);
+
+ % Calculate the observation filter
+ Oopt = RmeMtxMean.'/(RmmMtxMean + beta * eye(size(RmmMtxMean)));
+
+ % Reshape
+ Omean = permute(reshape(Oopt.', filtLen, size(m, 2), size(e, 2)), [3, 1, 2]);
end
% Mean cross-correlations between monitoring and virtual microphones over trials/sound field realisations
@@ -229,19 +280,4 @@ function [O, Rme, Rmm, Ovec, RmeMtx, RmmMtx, mMtx, Omean, RmeMean, RmmMean, Oopt
if nargout > 9
RmmMean = mean(Rmm, 5);
end
-
- % Average of optimal observation filters over trials/sound field realisations
- if nargout > 10
- Oopt = mean(Ovec, 3);
- end
-
- % Mean cross-correlation matrix between monitoring and virtual microphones over trials/sound field realisations
- if nargout > 11
- RmeMtxMean = mean(RmeMtx, 3);
- end
-
- % Mean cross-correlation matrix of monitoring microphones over trials/sound field realisations
- if nargout > 12
- RmmMtxMean = mean(RmmMtx, 3);
- end
end
\ No newline at end of file