Rescale Slope image petct

Hai..

Can everyone help me.

I have 47 slice PET image (Positron Emission Tomography). So i done extract value from all slice that contain pixel value from 20000 to 32767. My code like below.

P = zeros(256, 256, 47);
  for K = 1 : 47
     petname = sprintf('PET_I1001_PT%03d.dcm', K);
     P(:,:,K) = dicomread(petname);
  end
 [r,c,slice] = findND(P >= 20000 & P <= 32767)
 VALUE=P(P(:)>=20000 & P(:)<=32767 );

But my problem is, how to me multiply the VALUE i get with RescaleSlope itselp. I have code for extract RescaleSlope value, but it just extract the RescaleSlope by slice.

So i have to multiply manually. Now i want to it multiply automatically. The code for extract RescaleSlope like below.

for K = 47 : -1 : 1
  petname = sprintf('PET_I1001_PT%03d.dcm', K);
  thisinfo = dicominfo(petname);
  fn = fieldnames(thisinfo);
  for N = 1 : length(fn)
    thisfield = fn{N};
    info(K).(thisfield) = thisinfo.(thisfield);
  end
  this_slice = dicomread(petname);
  slices{K} = this_slice;
end
rescale_slopes = {info.RescaleSlope};
mask = cellfun(@isempty, rescale_slopes);
rescale_slopes(mask) = {0};       %set missing entries to 0
rescale_slopes = cell2mat(rescale_slopes);
inrange_mask = cellfun(@(M) any(M(:) >= 20000 & M(:) <= 32767), slices);
idx_of_inrange = find(inrange_mask);
rescale_slope_of_inrange = rescale_slopes(inrange_mask)