supdeq_lebedev

% SUpDEq - Spatial Upsampling by Directional Equalization

 function [gridData, Npoints, Nmax] = supdeq_lebedev(numOfSP, N)

 This function returns a Lebedev sampling grid with azimuth and elevation
 in degree plus the respective sampling weights.

 Output:
 gridData      - Q x 3 matrix where the first column holds the azimuth, the 
                 second the elevation, and the third the sampling weights.
 Npoints       - Total number of sampling points / nodes
 Nmax          - Highest stable grid order  

 Input:
 numOfSP       - Number of sampling points / nodes. 
                 Call supdeq_lebedev() to get a list of valid numbers.
 N             - Instead of numOfSP, the spatial order N of the Lebedev
                 grid can be passed. If N is passed, numOfSP will be
                 ignored.

 Dependencies: SOFiA toolbox

 (C) 2018 by JMA, Johannes M. Arend
             TH Köln - University of Applied Sciences
             Institute of Communications Engineering
             Department of Acoustics and Audio Signal Processing

0001 %% SUpDEq - Spatial Upsampling by Directional Equalization
0002 %
0003 % function [gridData, Npoints, Nmax] = supdeq_lebedev(numOfSP, N)
0004 %
0005 % This function returns a Lebedev sampling grid with azimuth and elevation
0006 % in degree plus the respective sampling weights.
0007 %
0008 % Output:
0009 % gridData      - Q x 3 matrix where the first column holds the azimuth, the
0010 %                 second the elevation, and the third the sampling weights.
0011 % Npoints       - Total number of sampling points / nodes
0012 % Nmax          - Highest stable grid order
0013 %
0014 % Input:
0015 % numOfSP       - Number of sampling points / nodes.
0016 %                 Call supdeq_lebedev() to get a list of valid numbers.
0017 % N             - Instead of numOfSP, the spatial order N of the Lebedev
0018 %                 grid can be passed. If N is passed, numOfSP will be
0019 %                 ignored.
0020 %
0021 % Dependencies: SOFiA toolbox
0022 %
0023 % (C) 2018 by JMA, Johannes M. Arend
0024 %             TH Köln - University of Applied Sciences
0025 %             Institute of Communications Engineering
0026 %             Department of Acoustics and Audio Signal Processing
0027 
0028 function [gridData, Npoints, Nmax] = supdeq_lebedev(numOfSP, N)
0029 
0030 if nargin == 0
0031     sofia_lebedev();
0032 end
0033     
0034 if nargin == 2
0035     %Get Lebedev sampling grid according to N
0036     lebN = [1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,17,20,23,26,29,32,35,38,41,44,47,50,53,56,59,62,65];
0037     lebNumPoints = [6, 14, 26, 38, 50, 74, 86, 110, 146, 170, 194, 230, 266, 302, 350, 434, 590, 770, 974, 1202, 1454, 1730, 2030, 2354, 2702, 3074, 3470, 3890, 4334, 4802, 5294, 5810];
0038     
0039     if isempty(find(N == lebN))
0040         error('No Lebedev grid available with given spatial order N.');
0041     end
0042  
0043     %Get numOfSP according to N
0044     numOfSP = lebNumPoints(find(N == lebN));
0045 end
0046 
0047 [gridData, Npoints, Nmax] = sofia_lebedev(numOfSP,0);
0048 %Convert from rad 2 deg
0049 gridData(:,1:2) = gridData(:,1:2)*180/pi;
0050 
0051 end
0052