daffv17_write.m 49.5 KB
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%
%  OpenDAFF
%

function [] = daffv17_write( varargin )
%DAFF_WRITE Create DAFF files
%   ...
%
%  --= General parameters =--
%
%  quiet        none        Suppress information and warning messages
%
%  -- Required --
%
%  filename     char        Output filename (*.daff)
%  content      char        Content type
%                           ('IR' => Impulse responses,
%                            'MS' => Magnitude spectra,
%                            'PS' => Phase spectra,
%                            'MPS' => Magnitude phase spectra,
%                            'DFT' => discrete fourier spectra)
%  datafunc     function    Data function (delivers the data for a direction)
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%  orient       vector-3    Orientation [yaw pitch roll] angles [°]        
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%  channels     int         Number of channels             
%
%  alphares     float       Resolution of alpha-angles
%  betares      float       Resolution of beta-angles
%       or
%  alphapoints  int         **TODO
%  betapoints   int         **TODO
%
%  -- Optional --
%
%  userdata     cell        User data that is passed to data function (default: empty cell array)
%  metadata     struct      Metadata information (see daffv17_add_metadata)
%
%  alpharange   vector-2    Range of alpha-angles
%  betarange    vector-2    Range of beta-angles
%
%  mdist        float       Measurement distance [m]
%  reference    float       Reference value [dB]
%
%   --= Impulse response content parameters =--
%
%  samplerate       float   Sampling rate [Hertz]
%  quantization     char    Element quantization (int16|int24|float32)
%  zthreshold       float   Detection threshold for zero-coefficients (default: -inf)
%
%   Options for magnitude spectra
%

    % --= Option definitions =--
    
    % Options with logical arguments (true|false)
    boolarg = {};
    
    % Options with integer number > 0 arguments
    ingzarg = {'alphapoints', 'betapoints', 'channels'};
    
   % Options with floating point number arguments
    floatarg = {'reference', 'zthreshold'};
             
    % Options with floating point number >= 0 arguments
    pfloatarg = {'alphares', 'betares', 'mdist', 'samplerate'};

    floatvecarg = {'alpharange', 'betarange', 'orient'};
             
    % Options with string parameters
    strarg = {'filename', 'content', 'quantization'};
      
    % Options without an argument
    nonarg = {'quiet'};
    
    % Options with one argument
    onearg = [ boolarg ingzarg floatarg pfloatarg floatvecarg strarg 'datafunc' 'metadata' 'userdata' ];
    
    % Required options
    reqarg = {'filename', 'content', 'datafunc', 'channels', 'orient'};    
    
    % +------------------------------------------------+
    % |                                                |
    % |   Parsing and validation of input parameters   |
    % |                                                |
    % +------------------------------------------------+
    
    % Parse the arguments
    args = struct();
    
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    % Switch between single cell argument call and option list
    if isa( varargin, 'cell' ) && length( varargin ) == 1 && isstruct( varargin{ 1 } )
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        args = varargin{ 1 };
        for i=1:length(nonarg)
            if ~isfield( args, nonarg{ i } )
                args.(  nonarg{ i } ) = false;
            end
        end
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    else

        for i=1:length(nonarg), args.(nonarg{i}) = false; end
        
        i=1;
        while i<=nargin
            if ~ischar(varargin{i}), error(['Parameter ' num2str(i) ': String expected']); end
            key = lower(varargin{i});
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            i = i+1;
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            r = nargin-i+1; % Number of remaining arguments

            switch key
            case nonarg
                args.(key) = true;

            % Options with one argument
            case onearg
                if (r < 1), error(['Option ''' key ''' requires an argument']); end
                args.(key) = varargin{i};
                i = i+1;

            otherwise
                error(['Invalid option (''' key ''')']);
            end        
        end
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    end
    
    % Validate the arguments
    for i=1:length(reqarg)
        key = reqarg{i};
        if ~isfield(args, key), error(['Option ''' key ''' must be specified']); end
    end
    
    for i=1:length(boolarg)
        key = boolarg{i};
        if isfield(args, key)
            if ~islogical(args.(key))
                error(['Argument for option ''' key ''' must be logical']);
            else
                % Type cast
                args.(key) = logical( args.(key) );
            end
        end
    end
    
    for i=1:length(ingzarg)
        key = ingzarg{i};
        if isfield(args, key)
            if (~isscalar(args.(key)) || ~any(isfinite(args.(key))) || ~isreal(args.(key)) || (ceil(args.(key)) ~= args.(key)) || (args.(key) <= 0))
                error(['Argument for option ''' key ''' must be an integer > 0']);
            else
                % Type cast
                args.(key) = int32( args.(key) );
            end
        end
    end
 
    for i=1:length(floatarg)
        key = floatarg{i};
        if isfield(args, key)
            if (~isscalar(args.(key)) || ~any(isfinite(args.(key))) || ~isreal(args.(key)))
                error(['Argument for option ''' key ''' must be a real number']);
            else
                % Type cast
                args.(key) = double( args.(key) );
            end
        end
    end
   
    for i=1:length(pfloatarg)
        key = pfloatarg{i};
        if isfield(args, key)
            if (~isscalar(args.(key)) || ~any(isfinite(args.(key))) || ~isreal(args.(key)) || (args.(key) < 0))
                error(['Argument for option ''' key ''' must be a non-negative real number']);
            else
                % Type cast
                args.(key) = double( args.(key) );
            end
        end
    end
    
    for i=1:length(floatvecarg)
        key = floatvecarg{i};
        if isfield(args, key)
            if (~isvector(args.(key)) || ~any(isfinite(args.(key))) || ~isreal(args.(key)))
                error(['Argument for option ''' key ''' must be a vector of real numbers']);
            else
                % Type cast
                args.(key) = double( args.(key) );
            end
        end
    end
    
    for i=1:length(strarg)
        key = strarg{i};
        if isfield(args, key)
            if (~ischar(args.(key)) || (length(args.(key)) == 0))
                error(['Argument for option ''' key ''' must be a non-empty string']);
            end
        end
    end
    
    % More validation ;-)
        
    fprintf( 'Writing DAFF file ''%s'' ... \n', args.filename );
    
    % Content
    args.content = upper(args.content);
    switch args.content
        case 'IR'
            contentStr = 'Impulse responses';
            contentType = 0; % DAFF_IMPULSE_RESPONSE
        case 'MS'
            contentStr = 'Magnitude spectra';
            contentType = 1; % DAFF_MAGNITUDE_SPECTRUM
        case 'PS'
            contentStr = 'Phase spectra';
            contentType = 2; % DAFF_PHASE_SPECTRUM
        case 'MPS'
            contentStr = 'Magnitude phase spectra';
            contentType = 3; % DAFF_MAGNITUDE_PHASE_SPECTRUM
        case 'DFT'
            contentStr = 'Discrete fourier spectra';
            contentType = 4; % DAFF_DFT_SPECTRUM
        
        otherwise
            error(['Invalid content type (' args.content ')']);
    end
    
    % Metadata
    if ~isfield(args, 'metadata')
        args.metadata = [];
	write_metadatablock = false;
    else 
	write_metadatablock = true;
    end;
    
    % Datafunction
    if (contentType == 4)
        if nargout(args.datafunc) ~= 4
            error('Argument for option ''datafunc'' must be a function which returns 4 arguments');
        end
    else
        if nargout(args.datafunc) ~= 3
            error('Argument for option ''datafunc'' must be a function which returns 3 arguments');
        end
    end
    
    % Angular ranges default values
    if ~isfield(args, 'alpharange'), args.alpharange = [0 360]; end
    if ~isfield(args, 'betarange'), args.betarange = [0 180]; end
        
    % Correct angular range ordering
    alphastart = min(args.alpharange);
    alphaend = max(args.alpharange);
    betastart = min(args.betarange);
    betaend = max(args.betarange);
    
    if ((alphastart < 0) || (alphastart > 360))
        error('Alpha range values must lie within the interval [0, 360]');
    end
    
    if ((betastart < 0) || (betastart > 180))
        error('Beta range values must lie within the interval [0, 180]');
    end  
    alphaspan = alphaend - alphastart;
    betaspan = betaend - betastart;
    
    % Alpha points and resolution
    if (~isfield(args, 'alphapoints') && ~isfield(args, 'alphares'))
        error('You must specify ''alphapoints'' or ''alphares''');
    end
    
    if (isfield(args, 'alphapoints') && isfield(args, 'alphares'))
        error('Specify either ''alphapoints'' or ''alphares'', but not both');
    end
    
    if isfield(args, 'alphares')
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        args.alphapoints = alphaspan / args.alphares;
        if abs( args.alphapoints - args.alphapoints ) > eps
            error( 'Alpha range and alpha resolution are not an integer multiple' )
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        end
    else
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        args.alphares = alphaspan / args.alphapoints;
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    end
   
    % Beta points and resolution
    if (~isfield(args, 'betapoints') && ~isfield(args, 'betares'))
        error('You must specify ''betapoints'' or ''betares''');
    end
    
    if (isfield(args, 'betapoints') && isfield(args, 'betares'))
        error('Specify either ''betapoints'' or ''betares'', but not both');
    end
    
    if (length(args.alpharange) ~= 2)
        error('Argument for ''alpharange'' must be a two element vector');
    end
    if (length(args.betarange) ~= 2)
        error('Argument for ''betarange'' must be a two element vector');
    end
    
    if isfield(args, 'betares')
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        args.betapoints = (betaspan / args.betares) + 1;
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        if (abs(args.betapoints - round(args.betapoints)) > 1e-5 )
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            error('Beta range and beta resolution are not an integer multiple')
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        else
           args.betapoints = round(args.betapoints); 
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        end
    else
        args.betares = betaspan / (args.betapoints-1);
    end

    % Orientation
    if (length(args.orient) ~= 3)
        error('Argument for ''orient'' must be a three element vector [yaw pitch roll]');
    end 
    
    % Measurement distance
    if ~isfield(args, 'mdist')
        fprintf(' * Assuming default measurement distance of 1m\n');
        args.mdist = 1;
    end 
       
    % Reference
    if ~isfield(args, 'reference')
        fprintf( ' * Setting reference value to 1.0 (0 dB)\n' );
        args.reference = 1.0;
    end 
    
    % Quantization
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    args.quantization = 'float32'; % Default except for IR
    quantizationType = 2; % DAFF_FLOAT32
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    if isfield( args, 'quantization' ) && strcmp( args.content, 'IR' )
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        args.quantization = lower(args.quantization);
        switch args.quantization
            case 'int16'
                quantizationStr = '16-bit signed integer';
                quantizationType = 0; % DAFF_INT16

            case 'int24'
                quantizationStr = '24-bit signed integer';
                quantizationType = 1; % DAFF_INT24
                
            case 'float32'
                quantizationStr = '32-bit floating point';
                quantizationType = 2; % DAFF_FLOAT32

            otherwise
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                error( 'Invalid quantization (%s)', args.quantization );
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        end
    end  
    
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    if strcmp( args.content, 'IR' )
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        % Validation for IR content
    
        % Zero-threshold (default value)
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        if ~isfield(args, 'zthreshold')
            args.zthreshold = -inf;
        end
        
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        zthreshold_value = 10^(args.zthreshold/20);    
    end
    
    % Default value for user data is an empty cell
    if ~isfield( args, 'userdata' )
		args.userdata = struct();
	end;
	
    % DEBUG: disp( args );

    % Print a summary of the information
    
    fprintf('Content type:       \t%s\n', contentStr);
    fprintf('Num channels:       \t%d\n', args.channels);
    fprintf('Num alpha points:   \t%d\n', args.alphapoints);
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    fprintf('Alpha range:        \t[%0.1f°, %0.1f°]\n', alphastart, alphaend);
    fprintf('Alpha resolution:   \t%0.1f°\n', args.alphares);
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    fprintf('Num beta points:   \t%d\n', args.betapoints);
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    fprintf('Beta range:        \t[%0.1f°, %0.1f°]\n', betastart, betaend);
    fprintf('Beta resolution:   \t%0.1f°\n', args.betares);
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    fprintf('Measurement dist.: \t%0.2f m\n', args.mdist);
    fprintf('Reference value:   \t%+0.1f dB\n', args.reference);

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    fprintf('Orientation:       \t(Y%+0.1f°, P%+0.1f°, R%+0.1f°)\n', ...
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                 args.orient(1), args.orient(2), args.orient(3));
    
    if strcmp(args.content, 'IR')
        fprintf('Quantization:      \t%s\n', quantizationStr);
        fprintf('Zero threshold:    \t%+0.1f dB (%0.6f)\n', args.zthreshold, zthreshold_value);
    end
    
    if strcmp(args.content, 'MS')
        % Nothing yet ...
    end    
    
    if strcmp(args.content, 'PS')
        % Nothing yet ...
    end    
    
    if strcmp(args.content, 'MPS')
        % Nothing yet ...
    end    
    
    if strcmp(args.content, 'DFT')
        % Nothing yet ...
    end    
    
    % +------------------------------------------------+
    % |                                                |
    % |   Analysis of the input data                   |
    % |                                                |
    % +------------------------------------------------+
      
    %
    %  Here we analyse all of the input data.
    %  It is ensured that all datasets have equal properties.
    %  The first dataset (for impulse responses) determines
    %  global properties (samplerate, filterlength)
    %
    
    props = struct();
    props.numRecords = 0;
    props.globalPeak = 0;
    props.eff_coeffs = 0;
    props.transformSize = 0;
    
    % Generate a list of all individual input data sets
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    % note: use round here to avoid errors if alphapoints are not exactly
    % integers but within epsilon
    x = cell( round( args.alphapoints ), round( args.betapoints ), args.channels );
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    % Speed up for itaHRTF class
    if isa( args.userdata, 'itaHRTF' )
        args.userdata = args.userdata.buildsearchdatabase;
    end
    
    disp( 'Starting to gather data via callback function, this might take a while ...' )
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    for b=1:args.betapoints
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        tic
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        beta = betastart + (b-1)*args.betares;
        
        % Write just one record at the poles
        if ((beta == 0) || (beta == 180))
            points = 1;
        else
            points = args.alphapoints;
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        end      
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        for a=1:points
            alpha = alphastart + (a-1)*args.alphares;
          
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            % --= Impulse responses =--         
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            if strcmp( args.content, 'IR' ) 
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                % Get the data
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                [ data, samplerate, metadata ] = args.datafunc( alpha, beta, args.userdata );
                [ channels, filterlength] = size( data );
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                if( ~isa( data, 'numeric' ) )
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                    error( 'Dataset (A%0.1f°, B%0.1f°): Data function must deliver double values', alpha, beta );
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                end
                
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                if isfield( props, 'samplerate' )
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                    if (samplerate ~= props.samplerate)
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                        error( 'Dataset (A%0.1f°, B%0.1f°): Sampling rate does not match', alpha, beta );
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                    end

                    if (channels ~= args.channels)
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                        error( 'Dataset (A%0.1f°, B%0.1f°): Number of channels does not match', alpha, beta );
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                    end

                    if (filterlength ~= props.filterlength)
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                       error( 'Dataset (A%0.1f°, B%0.1f°): Filter length does not match', alpha, beta );
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                    end
                else
                    % Now set the global properties, if they have not been set yet
                    props.samplerate = samplerate;
                    props.filterlength = filterlength;
                    props.elementsPerRecord = filterlength;

                    % Check filter length for 16-byte alignment
                    if( mod( filterlength, 4 ) ~= 0 )
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                        error( 'Dataset (A%0.1f°, B%0.1f°): Filter length is %d which is not a multiple of 4 (this is required for memory alignment)', alpha, beta, filterlength );
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                    end

                    fprintf('Global properties: Sampling rate = %d Hz, filter length = %d\n',...
                            props.samplerate, props.filterlength);
                end

                % Determine the peak value
                peak = max(max(abs(data)));
                props.globalPeak = max([props.globalPeak peak]);

                % Determine effective ranges of the filters
                % Important: We use C++ style indexing here (starting with 0)
                
                if (zthreshold_value == 0)
                    % No efficient storage => Full impulse responses
                    eoffsets = zeros(1, args.channels);
                    elengths = ones(1, args.channels)*filterlength;
                else
                    eoffsets = zeros(1, args.channels);
                    elengths = ones(1, args.channels)*filterlength;
                    
                    % Determine the effective bounds
                    for c=1:args.channels
                        [lwr, upr] = daffv17_effective_bounds(data(c,:), zthreshold_value);
                        
                        if (lwr == -1)
                            % No bounds. Store everything.
                            eoffsets(c) = 0;
                            elengths(c) = filterlength;
                        else
                            % Keep the offset and length a modulo of 4 (16-byte alignment)
                            % (Note: lwr-1 => switch from Matlab indexing to C-indexing)
                            elen = upr-lwr+1;
                            eoffsets(c) = daffv17_lwrmul(lwr-1, 4);
                            elengths(c) = daffv17_uprmul(elen, 4);
                        end
                    end
                end     
                        
                % Update savings by hidden zeros
                props.eff_coeffs = props.eff_coeffs + sum(elengths);
                
                % Update filter offsets and effective lengths
                if isfield(props, 'minFilterOffset')
                    props.minFilterOffset = min([props.minFilterOffset min(eoffsets)]);
                    props.maxEffectiveFilterLength = max([props.maxEffectiveFilterLength max(elengths)]);
                else
                    props.minFilterOffset = min(eoffsets);
                    props.maxEffectiveFilterLength = max(elengths);
                end
                
                % Store infos for record in cell
                for c=1:args.channels
                    x{a,b,c} = struct( 'peak', peak, ...
                                       'eoffset', eoffsets(c), ...
                                       'elength', elengths(c), ...
                                       'metadata', metadata, ...
                                       'metadataIndex', 0 ); 
                end
                
                write_metadatablock = write_metadatablock || ~isempty(metadata);
                            
                % Discard the data
                clear data;
                            
            end
            
            % --= Magnitude spectra =--
            
            if strcmp(args.content, 'MS') 
                % Get the data
                [ freqs, data, metadata ] = args.datafunc( alpha, beta, args.userdata );
                [channels, numfreqs] = size(data);

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                if ~isa( data, 'numeric' ) 
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                    error( 'Dataset (A%0.1f°, B%0.1f°): Data function must deliver double values', alpha, beta );
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                end
                
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                if isfield( props, 'freqs' )
                    if freqs ~= props.freqs
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                        error( 'Dataset (A%0.1f°, B%0.1f°): Frequency support does not match', alpha, beta );
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                    end

                    if (channels ~= args.channels)
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                        error( sprintf('Dataset (A%0.1f°, B%0.1f°): Number of channels does not match', alpha, beta) );
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                    end
                else
                    % Checks on the frequency support
                    if (numfreqs ~= size(freqs))
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                        error( sprintf('Dataset (A%0.1f°, B%0.1f°): Frequency support does not match', alpha, beta) );
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                    end;
                    
                    if (min(freqs) <= 0)
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                        error( sprintf('Dataset (A%0.1f°, B%0.1f°): Support frequencies must be greater zero', alpha, beta) );
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                    end;
            
                    if (sort(freqs) ~= freqs)
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                        error( sprintf('Dataset (A%0.1f°, B%0.1f°): Support frequencies must be stricly increasing', alpha, beta) );
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                    end   
        
                    if (length(unique(freqs)) ~= length(freqs))
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                        error( sprintf('Dataset (A%0.1f°, B%0.1f°): Support frequencies must be unique', alpha, beta) );
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                    end  
                    
                    % Now set the global properties, if they have not been set yet
                    props.numfreqs = numfreqs;
                    props.freqs = freqs;
                    props.elementsPerRecord = length(freqs);

                    fprintf('Global properties: Number of frequencies = %d\n', numfreqs);
                end

                % Important: Negative magnitudes are forbidden
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                if min( min( data ) ) < 0
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                    error( 'Dataset (A%0.1f°, B%0.1f°): Contains negative magnitudes', alpha, beta );
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                end
                
                
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                for c = 1:args.channels
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                    % Determine the peak value
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                    peak = max( max( data( c, : ) ) );
                    props.globalPeak = max( [ props.globalPeak peak ] );
                    
                    x{a,b,c} = struct(  'peak', peak, ...
                                        'metadata', metadata, ...
                                        'metadataIndex', 0 ...
                                        ); 
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                end
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				write_metadatablock = write_metadatablock || ~isempty(metadata);
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                % Discard the data
                clear data; 
            end
            
            
            % --= Phase spectra =--
            
            if strcmp(args.content, 'PS') 
                % Get the data
                [ freqs, data, metadata ] = args.datafunc( alpha, beta, args.userdata );
                [channels, numfreqs] = size(data);

                if (class(data) ~= 'double')
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                    error( sprintf('Dataset (A%0.1f°, B%0.1f°): Data function must deliver double values') );
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                end
                
                if isfield(props, 'freqs')
                    if (freqs ~= props.freqs)
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                        error( sprintf('Dataset (A%0.1f°, B%0.1f°): Frequency support does not match', alpha, beta) );
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                    end

                    if (channels ~= args.channels)
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                        error( sprintf('Dataset (A%0.1f°, B%0.1f°): Number of channels does not match', alpha, beta) );
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                    end
                else
                    % Checks on the frequency support
                    if (min(freqs) <= 0)
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                        error( sprintf('Dataset (A%0.1f°, B%0.1f°): Support frequencies must be greater zero', alpha, beta) );
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                    end;
            
                    if (sort(freqs) ~= freqs)
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                        error( sprintf('Dataset (A%0.1f°, B%0.1f°): Support frequencies must be stricly increasing', alpha, beta) );
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                    end   
        
                    if (length(unique(freqs)) ~= length(freqs))
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                        error( sprintf('Dataset (A%0.1f°, B%0.1f°): Support frequencies must be unique', alpha, beta) );
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                    end  
                    
                    % Now set the global properties, if they have not been set yet
                    props.numfreqs = numfreqs;
                    props.freqs = freqs;
                    props.elementsPerRecord = length(freqs);

                    fprintf('Global properties: Number of frequencies = %d\n', numfreqs);
                end

                % Important: Phases must range between +-pi
                if (min(min(data)) < -pi) || (max(max(data)) > pi)
663
                    error( sprintf('Dataset (A%0.1f°, B%0.1f°): Phases must range between +-pi', alpha, beta) );
664 665 666 667 668 669 670 671
                end
                
                props.globalPeak = 0;
                                
                for c=1:args.channels
                    x{a,b,c} = struct('metadata', metadata, ...
                                      'metadataIndex', 0); 
                end
672 673
                
                write_metadatablock = write_metadatablock || ~isempty(metadata);
674 675 676 677 678 679 680 681 682 683 684 685
                            
                % Discard the data
                clear data; 
            end
            
            % --= Magnitude phase spectra =--
            
            if strcmp(args.content, 'MPS') 
                % Get the data
                [ freqs, data, metadata ] = args.datafunc( alpha, beta, args.userdata );
                [channels, numfreqs] = size(data);

686
                if ~isa( data, 'numeric' )
687
                    error( 'Dataset (A%0.1f°, B%0.1f°): Data function must deliver double values', alpha, beta );
688 689
                end
                
690 691
                if isfield( props, 'freqs' )
                    if freqs ~= props.freqs
692
                        error( 'Dataset (A%0.1f°, B%0.1f°): Frequency support does not match', alpha, beta );
693 694
                    end

695
                    if channels ~= args.channels
696
                        error( 'Dataset (A%0.1f°, B%0.1f°): Number of channels does not match', alpha, beta );
697 698 699
                    end
                else
                    % Checks on the frequency support
700
                    if min(freqs) <= 0
701
                        error( 'Dataset (A%0.1f°, B%0.1f°): Support frequencies must be greater zero', alpha, beta );
702 703
                    end;
            
704
                    if sort(freqs) ~= freqs
705
                        error( 'Dataset (A%0.1f°, B%0.1f°): Support frequencies must be stricly increasing', alpha, beta );
706 707
                    end   
        
708
                    if length(unique(freqs)) ~= length(freqs)
709
                        error( 'Dataset (A%0.1f°, B%0.1f°): Support frequencies must be unique', alpha, beta );
710 711 712 713 714 715 716
                    end  
                    
                    % Now set the global properties, if they have not been set yet
                    props.numfreqs = numfreqs;
                    props.freqs = freqs;
                    props.elementsPerRecord = length(freqs);

717
                    fprintf( 'Global properties: Number of frequencies = %d\n', numfreqs );
718 719 720
                end
                
                % Determine the peak value
721 722
                peak = max( max( abs( data ) ) );
                props.globalPeak = max( [ props.globalPeak peak ] );
723 724 725 726 727
                    
                for c=1:args.channels
                    x{a,b,c} = struct('metadata', metadata, ... %'peak', peak, ...
                                      'metadataIndex', 0); 
                end
728 729
                
                write_metadatablock = write_metadatablock || ~isempty(metadata);
730 731 732 733 734 735 736
                            
                % Discard the data
                clear data; 
            end
            
            % --= DFT spectra =--
            
737
            if strcmp( args.content, 'DFT' )
738 739 740 741
                % Get the data
                [ data, sampleRate, isSymetric, metadata ] = args.datafunc( alpha, beta, args.userdata );
                [ channels, numDFTCoeffs ] = size( data );

742
                if ~isa( data, 'double' )
743
                    error( 'Dataset (A%0.1f°, B%0.1f°): Data function must deliver double values', alpha, beta );
744 745
                end
               
746
                if channels ~= args.channels 
747
                    error( 'Dataset (A%0.1f°, B%0.1f°): Data function must deliver matching channel numbers (%d != %d) ', alpha, beta, args.channels, channels );
748 749
                end
                
750
                if isa( isSymetric, 'logical' ) == 0 
751
                    error( 'Dataset (A%0.1f°, B%0.1f°): third parameter isSymetric must be logical', alpha, beta );
752 753 754 755
                end
                
                if isfield( props, 'samplerate' )
                    if ( sampleRate ~= props.sampleRate )
756
                        error( 'Dataset (A%0.1f°, B%0.1f°): Sample rate does not match', alpha, beta );
757 758 759
                    end
                end
                
760 761
                if isfield( props, 'numDFTCoeffs' )
                    if( numDFTCoeffs ~= props.numDFTCoeffs )
762
                        error( 'Dataset (A%0.1f°, B%0.1f°): Number of discrete fourier spectra coefficients is not constant', alpha, beta );
763 764
                    end
                else
765
                    if( numDFTCoeffs <= 0 )
766
                        error( 'Dataset (A%0.1f°, B%0.1f°): Number of discrete fourier spectra coefficients must be greater than zero', alpha, beta );
767 768 769 770 771 772 773 774 775 776 777 778
                    end
                    
                    props.numDFTCoeffs = numDFTCoeffs;
                    props.elementsPerRecord = numDFTCoeffs;
                    props.sampleRate = sampleRate;
                    
                    if isSymetric
                        props.transformSize = 2*numDFTCoeffs-1;
                    else
                        props.transformSize = numDFTCoeffs;
                    end
                    
779 780
                    fprintf( 'Global properties: Sampling rate = %d Hz, dft length = %d, transform size = %d\n',...
                             props.sampleRate, props.numDFTCoeffs, props.transformSize );
781
                end
782
                
783
                % Determine the peak value
784 785
                peak = max( max( abs( data ) ) );
                props.globalPeak = max( [ props.globalPeak peak ] );
786
                
787
                for c = 1:args.channels
788 789 790
                    x{a,b,c} = struct('metadata', metadata, ... %'peak', peak, ...
                                      'metadataIndex', 0); 
                end
791 792
                
                write_metadatablock = write_metadatablock || ~isempty( metadata );
793 794 795 796 797 798 799
                            
                % Discard the data
                clear data; 
            end
            
            props.numRecords = props.numRecords + 1;
        end
800 801
        
        disp( [ 'Processed beta angle ' num2str( beta ) ', took ' num2str( toc ) ] )
802
    end
803
    disp( '... and data has been assembled. Will write to file now.' )
804
        
805
    fprintf( 'Global peak: %+0.1f dB (%0.6f)\n', 20*log10(props.globalPeak), props.globalPeak );
806 807 808 809 810 811 812 813 814 815 816 817 818 819 820 821 822 823 824 825 826 827 828 829 830 831 832 833 834 835 836 837 838 839 840 841 842 843 844 845 846 847 848 849 850 851 852 853 854 855 856 857 858 859 860 861 862 863 864 865 866 867 868 869 870 871 872 873 874 875 876 877 878 879 880 881 882 883 884 885 886 887 888 889 890 891 892 893 894 895 896 897 898 899 900 901 902 903 904 905 906 907 908 909 910 911 912 913 914 915 916 917 918 919 920 921 922 923 924 925 926 927 928 929 930 931 932 933 934 935 936 937 938 939 940 941 942 943 944 945 946 947 948 949 950 951 952 953 954 955 956 957 958
  
    if strcmp(args.content, 'IR')
        % Calculate to overall storage saving
        props.total_coeffs = args.channels * props.numRecords * filterlength;
        props.zsavings = double(props.total_coeffs - props.eff_coeffs) / double(props.total_coeffs) * 100;
        
        fprintf('Minimum filter offset: %d\n', props.minFilterOffset);
        fprintf('Maximum effective filter length: %d\n', props.maxEffectiveFilterLength);
        fprintf('Storage space saved: %0.1f%%\n', props.zsavings);
    end  
    
    % +------------------------------------------------+
    % |                                                |
    % |   Writing of the output file                   |
    % |                                                |
    % +------------------------------------------------+
      
    % Current version = 1.7
    FileFormatVersion = 0170;
    
    % Important! 'l' -> little endian (DAFF files are always little endian)
    fid = fopen(args.filename, 'wb', 'l'); 
    fpos = struct();
    
    %
    %  1st step: Write the file header
    %
   
    if (write_metadatablock > 0)
        iNumFileBlocks = 5;
    else
        iNumFileBlocks = 4;
    end

    fwrite(fid, 'FW', 'char');
    fwrite(fid, FileFormatVersion, 'int32');
    fwrite(fid, iNumFileBlocks, 'int32');
    
    % File block entries
    % Note: Remember the positions for later data insertion
    
    % Main header (FILEBLOCK_DAFF1_MAIN_HEADER = 0x0001)
    fwrite(fid, hex2dec('0001'), 'int32');
    fpos.MainHeaderOffset = ftell(fid);
    fwrite(fid, 0, 'uint64');
    fpos.MainHeaderSize = ftell(fid);
    fwrite(fid, 0, 'uint64');
    
    % Content header (FILEBLOCK_DAFF1_CONTENT_HEADER = 0x0002)
    fwrite(fid, hex2dec('0002'), 'int32');
    fpos.ContentHeaderOffset = ftell(fid);
    fwrite(fid, 0, 'uint64');
    fpos.ContentHeaderSize = ftell(fid);
    fwrite(fid, 0, 'uint64');
    
    % Record descriptor block (FILEBLOCK_DAFF1_RECORD_DESC = 0x0003)
    fwrite(fid, hex2dec('0003'), 'int32');
    fpos.RecordDescOffset = ftell(fid);
    fwrite(fid, 0, 'uint64');
    fpos.RecordDescSize = ftell(fid);
    fwrite(fid, 0, 'uint64');
    
    % Data block (FILEBLOCK_DAFF1_DATA  = 0x0004)
    fwrite(fid, hex2dec('0004'), 'int32');
    fpos.DataOffset = ftell(fid);
    fwrite(fid, 0, 'uint64');
    fpos.DataSize = ftell(fid);
    fwrite(fid, 0, 'uint64');
    
    if (write_metadatablock > 0)
        % Metadata block (FILEBLOCK_DAFF1_METADATA = 0x0005)
        fwrite(fid, hex2dec('0005'), 'int32');
        fpos.MetadataOffset = ftell(fid);
        fwrite(fid, 0, 'uint64');
        fpos.MetadataSize = ftell(fid);
        fwrite(fid, 0, 'uint64');
    end
    
    %
    %  2nd step: Write the main header
    %
   
    MainHeaderOffset = ftell(fid);
    
    fwrite(fid, contentType, 'int32');
    fwrite(fid, quantizationType, 'int32');
    fwrite(fid, args.channels, 'int32');
    fwrite(fid, props.numRecords, 'int32');
    fwrite(fid, props.elementsPerRecord, 'int32');
    %fwrite(fid, args.mdist, 'float32'); % WARNING this values is overwritten.
    fwrite(fid, -1, 'int32');

    fwrite(fid, args.alphapoints, 'int32');
    fwrite(fid, alphastart, 'float32');
    fwrite(fid, alphaend, 'float32');

    fwrite(fid, args.betapoints, 'int32');
    fwrite(fid, betastart, 'float32');
    fwrite(fid, betaend, 'float32');

    fwrite(fid, args.orient(1), 'float32');
    fwrite(fid, args.orient(2), 'float32');
    fwrite(fid, args.orient(3), 'float32');
 
    MainHeaderSize = ftell(fid) - MainHeaderOffset;
    
    %
    %  3rd step: Write the content specific header
    %
    
    ContentHeaderOffset = ftell(fid);
 
    % --= Impulse responses =--
 
    if strcmp(args.content, 'IR') 
        fwrite(fid, props.samplerate, 'float32');
        %fwrite(fid, args.reference, 'float32'); %WARNING this field does not exist in 105 DAFF
        fwrite(fid, props.minFilterOffset, 'int32');
        fwrite(fid, props.maxEffectiveFilterLength, 'int32');
    end
        
    % --= Magnitude spectra =--
          
    if strcmp(args.content, 'MS') 
        % Number of frequencies
        fwrite(fid, props.globalPeak, 'float32');
        fwrite(fid, props.numfreqs, 'int32');
        fwrite(fid, props.freqs, 'float32');
    end  
    
    % --= Phase spectra =--
          
    if strcmp(args.content, 'PS') 
        % Number of frequencies
        fwrite(fid, props.numfreqs, 'int32');
        fwrite(fid, props.freqs, 'float32');
    end  
    
    % --= Magnitude-phase spectra =--
          
    if strcmp(args.content, 'MPS') 
        % Number of frequencies
        fwrite(fid, props.globalPeak, 'float32');
        fwrite(fid, props.numfreqs, 'int32');
        fwrite(fid, props.freqs, 'float32');
    end  

    % --= DFT spectra =--
          
    if strcmp(args.content, 'DFT') 
        % Number of frequencies
        fwrite(fid, props.numDFTCoeffs, 'int32');
        fwrite(fid, props.transformSize, 'int32');
959
        fwrite(fid, props.sampleRate, 'float32');
960 961 962 963 964 965 966 967 968 969 970 971 972 973 974 975 976 977 978 979 980 981 982 983 984 985 986 987 988 989 990 991 992 993 994 995 996 997 998 999 1000 1001 1002 1003 1004 1005 1006 1007 1008 1009 1010 1011 1012 1013 1014 1015 1016 1017 1018 1019 1020 1021
        fwrite(fid, props.globalPeak, 'float32');
    end  
    
    ContentHeaderSize = ftell(fid) - ContentHeaderOffset;
    
    % Adjust 16-Byte alignment
    nfill = mod(ftell(fid),16);
    if (nfill > 0)
        for i=1:(16-nfill), fwrite(fid, 0, 'uint8'); end;
    end
        
    %
    %  4rd step: Write the record descriptor table
    %
    
	RecordDescOffset = ftell(fid);
    
    % Note: Here we do not write the actual descriptors, since they are
    %       unknown so far. We write placeholder and insert the data later...
    
    if strcmp(args.content, 'IR') 
        % Note: Each IR record desc is 4+4+4+8 Byte = 20 Byte
        fwrite(fid, zeros(1, 20*props.numRecords*args.channels, 'uint8'), 'uint8');
    else % default (MS/PS/MPS/DFT)
        % Note: Each MS/PS/MPS/DFT record desc is 4+8=12 Byte
        fwrite(fid, zeros(1, 12*props.numRecords*args.channels, 'uint8'), 'uint8');
    end
    
    
    RecordDescSize = ftell(fid) - RecordDescOffset;
    
    % Adjust 16-Byte alignment
    nfill = mod(ftell(fid),16);
    if (nfill > 0)
        for i=1:(16-nfill), fwrite(fid, 0, 'uint8'); end;
    end
         
    %
    %  5th step: Write the data itself
    %
    
    DataOffset = ftell(fid);
 
    if strcmp(args.content, 'IR') 
        
        for b=1:args.betapoints
            beta = betastart + (b-1)*args.betares;
            
            % Write just one record at the poles
            if ((beta == 0) || (beta == 180))
                points = 1;
            else
                points = args.alphapoints;
            end

            for a=1:points
                alpha = alphastart + (a-1)*args.alphares;
                
                % Get the data (2nd time)
                [ data, ~, ~ ] = args.datafunc( alpha, beta, args.userdata );

                if( ~isa( data, 'double' ) )
1022
                    error( 'Dataset (A%0.1f°, B%0.1f°): Data function must deliver double values', alpha, beta );
1023 1024 1025 1026
                end
 
                % Clipping check
                peak = max(max(abs(data)));
1027
                if ( peak > 1 ) && ( ~args.quiet ) && ( quantizationType ~= 2 )
1028
                    warning( 'Dataset (A%0.1f°, B%0.1f°): Clipping occured (peak %0.3f)', alpha, beta, peak );
1029 1030 1031 1032 1033 1034 1035 1036 1037 1038 1039 1040 1041 1042 1043
                end
                   
                for c=1:args.channels
                    % Remember the offset of this records/channels data
                    % Important: Relative to the beginning of the data block
                    x{a,b,c}.dataOffset = ftell(fid) - DataOffset;
                    
                    % Effective boundaries (Matlab indices)
                    i1 = x{a,b,c}.eoffset + 1;
                    i2 = i1 + x{a,b,c}.elength - 1;
                    
                    switch args.quantization
                    case 'int16'
                        % Dynamic range: 2^15-1 = 32767
                        cdata = int16( data(c,i1:i2)*32767 );
1044
                        fwrite( fid, cdata, 'int16' );
1045 1046 1047 1048 1049 1050 1051 1052 1053 1054 1055 1056 1057 1058 1059 1060 1061 1062 1063 1064 1065 1066 1067 1068 1069 1070 1071 1072 1073 1074 1075 1076 1077 1078

                    case 'int24'
                        % Dynamic range: 2^23-1 = 8388607
                        cdata = int32( data(c,i1:i2)*8388607 );
                        fwrite(fid, cdata, 'int24');

                    case 'float32'
                        fwrite(fid, data(c,i1:i2), 'float32');
                    end
                end
            end
        end
    end
    
    if strcmp(args.content, 'MS') 
        
        for b=1:args.betapoints
            beta = betastart + (b-1)*args.betares;
            
            % Write just one record at the poles
            if ((beta == 0) || (beta == 180))
                points = 1;
            else
                points = args.alphapoints;
            end

            for a=1:points
                alpha = alphastart + (a-1)*args.alphares;
                
                % Get the data (2nd time)
                [ freqs, data ] = args.datafunc( alpha, beta, args.userdata );
                [channels, numfreqs] = size(data);

                if (class(data) ~= 'double')
1079
                    error( sprintf('Dataset (A%0.1f°, B%0.1f°): Data function must deliver double values') );
1080 1081 1082 1083
                end
 
                % Clipping check
                peak = max(max(data));
1084
                if ( peak > 1.0 ) && ( ~args.quiet ) && ( quantizationType ~= 2 )
1085
                    warning( 'Dataset (A%0.1f°, B%0.1f°): Clipping occured (peak %0.3f)', alpha, beta, peak );
1086 1087 1088 1089 1090 1091 1092 1093 1094 1095 1096 1097 1098 1099 1100 1101 1102 1103 1104 1105 1106 1107 1108 1109 1110 1111 1112 1113 1114 1115 1116 1117 1118 1119 1120 1121
                end
                   
                %x{a,b}.dataOffset = zeros(1, args.channels); 
                % TODO: find right syntax to do this
                for c=1:args.channels
                    % Remember the offset of this records/channels data
                    % Important: Relative to the beginning of the data block
                    x{a,b,c}.dataOffset = ftell(fid) - DataOffset;
   
                    fwrite(fid, data(c,:), 'float32');
                end
            end
        end
    end
    
    
    if strcmp(args.content, 'PS') 
        
        for b=1:args.betapoints
            beta = betastart + (b-1)*args.betares;
            
            % Write just one record at the poles
            if ((beta == 0) || (beta == 180))
                points = 1;
            else
                points = args.alphapoints;
            end

            for a=1:points
                alpha = alphastart + (a-1)*args.alphares;
                
                % Get the data (2nd time)
                [ freqs, data ] = args.datafunc( alpha, beta, args.userdata );
                [channels, numfreqs] = size(data);

                if (class(data) ~= 'double')
1122
                    error( sprintf('Dataset (A%0.1f°, B%0.1f°): Data function must deliver double values') );
1123 1124 1125 1126 1127 1128 1129 1130 1131 1132 1133 1134 1135 1136 1137 1138 1139 1140 1141 1142 1143 1144 1145 1146 1147 1148 1149 1150 1151 1152 1153 1154 1155 1156 1157
                end
                   
                %x{a,b}.dataOffset = zeros(1, args.channels); TODO
                for c=1:args.channels
                    % Remember the offset of this records/channels data
                    % Important: Relative to the beginning of the data block
                    x{a,b,c}.dataOffset = ftell(fid) - DataOffset;
   
                    fwrite(fid, data(c,:), 'float32');
                end
            end
        end
    end
    
    
    if strcmp(args.content, 'MPS') 
        
        for b=1:args.betapoints
            beta = betastart + (b-1)*args.betares;
            
            % Write just one record at the poles
            if ((beta == 0) || (beta == 180))
                points = 1;
            else
                points = args.alphapoints;
            end

            for a=1:points
                alpha = alphastart + (a-1)*args.alphares;
                
                % Get the data (2nd time)
                [ freqs, data ] = args.datafunc( alpha, beta, args.userdata );
                [ channels, numfreqs ] = size( data );

                if (class(data) ~= 'double')
1158
                    error( sprintf('Dataset (A%0.1f°, B%0.1f°): Data function must deliver double values') );
1159 1160 1161 1162 1163 1164 1165 1166 1167 1168 1169 1170 1171 1172 1173 1174 1175 1176 1177 1178 1179 1180 1181 1182 1183 1184 1185 1186 1187 1188 1189 1190 1191 1192 1193 1194 1195 1196 1197
                end
                   
                %x{a,b}.dataOffset = zeros(1, args.channels); TODO
                for c=1:args.channels
                    % Remember the offset of this records/channels data
                    % Important: Relative to the beginning of the data block
                    x{a,b,c}.dataOffset = ftell(fid) - DataOffset;
   
                    start = ftell(fid);
                    fseek(fid, -4, 'cof');
                    fwrite(fid, real(data(c,:)), 'float32', 4);
                    fseek(fid, start, 'bof');
                    fwrite(fid, imag(data(c,:)), 'float32', 4);
                end
            end
        end
    end
    
    
    if strcmp(args.content, 'DFT') 
        
        for b=1:args.betapoints
            beta = betastart + (b-1)*args.betares;
            
            % Write just one record at the poles
            if ((beta == 0) || (beta == 180))
                points = 1;
            else
                points = args.alphapoints;
            end

            for a=1:points
                alpha = alphastart + (a-1)*args.alphares;
                
                % Get the data (2nd time)
                [ data ] = args.datafunc( alpha, beta, args.userdata );
                [ channels, numfreqs ] = size( data );

                if (class(data) ~= 'double')
1198
                    error( sprintf('Dataset (A%0.1f°, B%0.1f°): Data function must deliver double values') );
1199 1200 1201 1202 1203 1204 1205 1206 1207 1208 1209 1210 1211 1212 1213 1214 1215 1216 1217 1218 1219 1220 1221 1222 1223 1224 1225 1226 1227 1228 1229 1230 1231 1232 1233 1234 1235 1236 1237 1238 1239 1240 1241 1242 1243 1244 1245 1246 1247 1248 1249 1250 1251 1252 1253 1254 1255 1256 1257 1258 1259 1260 1261 1262 1263 1264 1265 1266 1267 1268 1269 1270 1271 1272 1273 1274 1275 1276 1277 1278 1279 1280 1281 1282 1283 1284 1285 1286 1287 1288 1289 1290 1291 1292 1293 1294 1295 1296 1297 1298 1299 1300 1301 1302 1303 1304 1305 1306 1307 1308 1309 1310 1311 1312 1313 1314 1315 1316 1317 1318 1319 1320 1321 1322 1323 1324 1325 1326 1327 1328 1329 1330 1331 1332 1333 1334 1335 1336 1337 1338 1339 1340 1341 1342 1343 1344 1345 1346 1347 1348 1349 1350 1351 1352 1353 1354 1355 1356 1357 1358 1359 1360 1361 1362 1363 1364 1365 1366 1367 1368 1369 1370 1371
                end
                   
                %x{a,b}.dataOffset = zeros(1, args.channels); TODO
                for c=1:args.channels
                    % Remember the offset of this records/channels data
                    % Important: Relative to the beginning of the data block
                    x{a,b,c}.dataOffset = ftell(fid) - DataOffset;
                                        
                    %for z=1:numfreqs
                    %    fwrite(fid, real(data(c,z)), 'float32');
                    %    fwrite(fid, imag(data(c,z)), 'float32');
                    %end
                    
                    start = ftell(fid);
                    fseek(fid, -4, 'cof');
                    fwrite(fid, real(data(c,:)), 'float32', 4);
                    fseek(fid, start, 'bof');
                    fwrite(fid, imag(data(c,:)), 'float32', 4);

                end
            end
        end
    end

    DataSize = ftell(fid) - DataOffset;
        
    %
    %  6th step: Write the metadata
    %
    
    if (write_metadatablock > 0)
        MetadataOffset = ftell(fid);
        
        % write metadata for the whole file
        index = 0;
        if ~isempty(args.metadata)
            % args.metadata = daffv17_add_metadata(args.metadata, 'version', 'char', FileFormatVersion); 
            % write something, so args.metadata is not empty
            daffv17_write_metadata(fid, args.metadata);  
            index = 1;
        end
        
        % write metadata for each record
        for b=1:args.betapoints
            beta = betastart + (b-1)*args.betares;
             
            % Write just one metadata block for each pole
            if ((beta == 0) || (beta == 180))
                points = 1;
            else
                points = args.alphapoints;
            end

            for a=1:points
                if ~isempty(x{a,b,1}.metadata) % allways check the first channel for metadata
                    % TODO: validate metadata structure
                    daffv17_write_metadata(fid, x{a,b,1}.metadata); 
                    for c=1:args.channels % but write index to all channels
                        x{a,b,c}.metadataIndex = index;
                    end
                    index = index + 1;
                else
                    for c=1:args.channels
                        x{a,b,c}.metadataIndex = 0;
                    end
                end
            end
        end
        
        MetadataSize = ftell(fid) - MetadataOffset;

        fprintf('Number of written Metadata objects: %d\n', index);
    end
    
    %
    %  7th step: Update the record descriptors
    %
    
    fseek(fid, RecordDescOffset, 'bof');
    
    if strcmp(args.content, 'IR') 
        for b=1:args.betapoints
            beta = betastart + (b-1)*args.betares;
            
            % Write just one record at the poles
            if ((beta == 0) || (beta == 180))
                points = 1;
            else
                points = args.alphapoints;
            end

            for a=1:points
                for c=1:args.channels
                    fwrite(fid, x{a,b,c}.metadataIndex, 'int32');
                    fwrite(fid, x{a,b,c}.dataOffset, 'uint64');
                    fwrite(fid, x{a,b,c}.eoffset, 'int32');
                    fwrite(fid, x{a,b,c}.elength, 'int32');
    
                    % DEBUG: fprintf('Data offset alpha = %d, beta = %d, channel %d = %d\n', a, b, c, x{a,b}(c).dataOffset);
                end
            end
        end
    else % default (MS,PS,MPS,DFT)
        for b=1:args.betapoints
            beta = betastart + (b-1)*args.betares;
            
            % Write just one record at the poles
            if ((beta == 0) || (beta == 180))
                points = 1;
            else
                points = args.alphapoints;
            end

            for a=1:points
                for c=1:args.channels
                    fwrite(fid, x{a,b,c}.metadataIndex, 'int32');
                    fwrite(fid, x{a,b,c}.dataOffset, 'uint64');
                end
            end
        end
    end
    
    %
    %  8th step: Finally insert offsets and sizes into the file header
    %
  
    fseek(fid, fpos.MainHeaderOffset, 'bof');
    fwrite(fid, MainHeaderOffset, 'uint64');
    
    fseek(fid, fpos.MainHeaderSize, 'bof');
    fwrite(fid, MainHeaderSize, 'uint64');
    
    fseek(fid, fpos.ContentHeaderOffset, 'bof');
    fwrite(fid, ContentHeaderOffset, 'uint64');
    
    fseek(fid, fpos.ContentHeaderSize, 'bof');
    fwrite(fid, ContentHeaderSize, 'uint64');
    
    fseek(fid, fpos.RecordDescOffset, 'bof');
    fwrite(fid, RecordDescOffset, 'uint64');
    
    fseek(fid, fpos.RecordDescSize, 'bof');
    fwrite(fid, RecordDescSize, 'uint64');
    
    fseek(fid, fpos.DataOffset, 'bof');
    fwrite(fid, DataOffset, 'uint64');    
    
    fseek(fid, fpos.DataSize, 'bof');
    fwrite(fid, DataSize, 'uint64');    
    
    if (write_metadatablock > 0)
        fseek(fid, fpos.MetadataOffset, 'bof');
        fwrite(fid, MetadataOffset, 'uint64');
    
        fseek(fid, fpos.MetadataSize, 'bof');
        fwrite(fid, MetadataSize, 'uint64');
    end
    
    fclose(fid);

    % -----------------------------------------------------
    
    % Some more information
    fprintf('Content header size = %d bytes\n', ContentHeaderSize);
    fprintf('Record descriptor size = %d bytes\n', RecordDescSize);
    fprintf('Data size = %d bytes\n', DataSize);
    if (write_metadatablock > 0)
        fprintf('Metadata size = %d bytes\n', MetadataSize);
    end
    
    % What we all been waiting for...
    fprintf( ' ... DAFF file ''%s'' successfully written.\n', args.filename );
end