loop vectorization for below code

Hi, I was wondering if there is a fast way to vectorize this code.

idx_A=1; idx_B=1; idx_C = 1;
for idx=1:length(temp)
  if ~image(x(idx),y(idx))==0 
      lA(idx_A)= handles.Val(idx);
      idx_A=idx_A+1;
  end
  if handles.Morph.Threshold_MapFrame(x(idx),y(idx))==0.5
      lB(idx_B)= handles.Val(idx);
      idx_B=idx_B+1;
  end
  if handles.Morph.Threshold_MapFrame(x(idx),y(idx))>0.5
      lC(idx_C)= handles.Val(idx);
      idx_C=idx_C+1;
  end    
end