ivan@140: function solver=CVX_add_const_Audio_declipping(Problem, solver, idxFrame)
ivan@140: 
ivan@140: %% CVX additional constrains 
ivan@140:     % Clipping level: take the analysis window into account
ivan@140:     % clipping level detection
ivan@140:     
ivan@140:     signal = Problem.b1;
ivan@140:     signalFull = Problem.b(:,idxFrame);
ivan@140:     Dict = Problem.A;
ivan@140:     DictFull = Problem.B;
ivan@140:     Clipped = ~Problem.M(:,idxFrame);
ivan@140:     W=1./sqrt(diag(Dict'*Dict));
ivan@140:     
ivan@140:     idxCoeff = find(solver.solution~=0);
ivan@140:     
ivan@140:     solution = solver.solution;
ivan@140:     
ivan@140:     wa = Problem.wa(Problem.windowSize); % analysis window
ivan@140:     
ivan@140:     
ivan@140:     clippingLevelEst = max(abs(signal./wa(~Clipped)'));
ivan@140: 
ivan@140:     idxPos = find(signalFull>=0 & Clipped);
ivan@140:     idxNeg = find(signalFull<0  & Clipped);
ivan@140: 
ivan@140:     DictPos=DictFull(idxPos,:);
ivan@140:     DictNeg=DictFull(idxNeg,:);
ivan@140:     
ivan@140:     
ivan@140:     wa_pos = wa(idxPos);
ivan@140:     wa_neg = wa(idxNeg);
ivan@140:     b_ineq_pos = wa_pos(:)*clippingLevelEst;
ivan@140:     b_ineq_neg = -wa_neg(:)*clippingLevelEst;
ivan@140:     if isfield(Problem,'Upper_Limit') && ~isempty(Problem.Upper_Limit)
ivan@140:         b_ineq_pos_upper_limit = wa_pos(:)*Problem.Upper_Limit*clippingLevelEst;
ivan@140:         b_ineq_neg_upper_limit = -wa_neg(:)*Problem.Upper_Limit*clippingLevelEst;
ivan@140:     else
ivan@140:         b_ineq_pos_upper_limit = Inf;
ivan@140:         b_ineq_neg_upper_limit = -Inf;
ivan@140:     end
ivan@140:     
ivan@140:     
ivan@140:     j = length(idxCoeff);
ivan@140:     
ivan@140:     if isinf(b_ineq_pos_upper_limit)
ivan@140:         %% CVX code
ivan@140:         cvx_begin
ivan@140:         cvx_quiet(true)
ivan@140:         variable solution(j)
ivan@140:         minimize(norm(Dict(:,idxCoeff)*solution-signal))
ivan@140:         subject to
ivan@140:         DictPos(:,idxCoeff)*(W(idxCoeff).*solution) >= b_ineq_pos
ivan@140:         DictNeg(:,idxCoeff)*(W(idxCoeff).*solution) <= b_ineq_neg
ivan@140:         cvx_end
ivan@140:         if cvx_optval>1e3
ivan@140:             cvx_begin
ivan@140:             cvx_quiet(true)
ivan@140:             variable solution(j)
ivan@140:             minimize(norm(Dict(:,idxCoeff)*solution-xObs))
ivan@140:             cvx_end
ivan@140:         end
ivan@140:     else
ivan@140:         %% CVX code
ivan@140:         cvx_begin
ivan@140:         cvx_quiet(true)
ivan@140:         variable solution(j)
ivan@140:         minimize(norm(Dict(:,idxCoeff)*solution-signal))
ivan@140:         subject to
ivan@140:         DictPos(:,idxCoeff)*(W(idxCoeff).*solution) >= b_ineq_pos
ivan@140:         DictNeg(:,idxCoeff)*(W(idxCoeff).*solution) <= b_ineq_neg
ivan@140:         DictPos(:,idxCoeff)*(W(idxCoeff).*solution) <= b_ineq_pos_upper_limit
ivan@140:         DictNeg(:,idxCoeff)*(W(idxCoeff).*solution) >= b_ineq_neg_upper_limit
ivan@140:         cvx_end
ivan@140:         if cvx_optval>1e3
ivan@140:             cvx_begin
ivan@140:             cvx_quiet(true)
ivan@140:             variable solution(j)
ivan@140:             minimize(norm(Dict(:,idxCoeff)*solution-xObs))
ivan@140:             cvx_end
ivan@140:         end
ivan@140:     end
ivan@140:  
ivan@140:    solver.solution(idxCoeff) = solution;
ivan@140:     
ivan@140: