matthiasm@8: function [chromaframes, info] = hpcp2chroma(hpcpframes, info)
matthiasm@8: 
matthiasm@8: % calculate the best shift 
matthiasm@8: % (0 - none, 1 - one third of semitone down, 
matthiasm@8: %  2 - two thirds of semitone down)
matthiasm@8: 
matthiasm@8: bps = info.binsperoctave/12;
matthiasm@8: 
matthiasm@8: indices = (0:11) * bps;
matthiasm@8: 
matthiasm@8: 
matthiasm@8: %%%%% NANs! $%%%%%%%%%%%%
matthiasm@8: % nanrows = isnan(sum(hpcpframes,2));
matthiasm@8: % binweights = sum(hpcpframes(~nanrows,:));
matthiasm@8: % condensedweights = zeros(bps,12);
matthiasm@8: % for iBin = 1:bps
matthiasm@8: %     condensedweights(iBin,1:12) = sum(binweights(indices+iBin)); 
matthiasm@8: % end
matthiasm@8: % % [maximum, maxind] = max(...
matthiasm@8: % %     [sum(binweights(indices+1)),...
matthiasm@8: % %      sum(binweights(indices+2)),...
matthiasm@8: % %      sum(binweights(indices+3))]);
matthiasm@8: % [maximum, maxind] = max(sum(condensedweights,2));
matthiasm@8: % shiftposs = [1 0 -1];
matthiasm@8: % shift = shiftposs(maxind);
matthiasm@8: % if bps ==3
matthiasm@8: %     hpcpframes = circshift(hpcpframes',shift)';
matthiasm@8: %     info.tuning6th = shift;
matthiasm@8: % end
matthiasm@8: maxind = 1;
matthiasm@8: 
matthiasm@8: % fprintf(1,['(max. energy at ' num2str(maxind) ', shift by ' num2str(shift) ')\n\n'])
matthiasm@8: if (~info.maxx)
matthiasm@8:     if bps == 3
matthiasm@8:         chromaframes = ...
matthiasm@8:             0 * hpcpframes(:,indices+1) + ...
matthiasm@8:             1 * hpcpframes(:,indices+2) + ...
matthiasm@8:             0 * hpcpframes(:,indices+3);
matthiasm@8:     elseif bps == 2
matthiasm@8:         chromaframes = ...
matthiasm@8:             (1-shift)* hpcpframes(:,indices+1) + ...
matthiasm@8:              shift* hpcpframes(:,indices+2);
matthiasm@8:     elseif bps == 1
matthiasm@8:         chromaframes = hpcpframes;
matthiasm@8:     end
matthiasm@8: else
matthiasm@8:     chromaframes = zeros(size(hpcpframes,1),12);
matthiasm@8:     for iChroma = 1:12
matthiasm@8:         chromaframes(:,iChroma) = max(hpcpframes(:,indices(iChroma)+(1:3)),[],2);
matthiasm@8:     end
matthiasm@8: end
matthiasm@8: 
matthiasm@8: chromaframes = chromaframes ./ repmat(sum(chromaframes,2),1,12);