a b/R/quick_lung_mask.R 

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#' @rdname segment_lung





  
  

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#' @export





  
  

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#' @importFrom ANTsR connectedThreshold maskImage





  
  

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#' @importFrom ANTsRCore iMath





  
  

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quick_lung_mask = function(img,





  
  

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                           lthresh = -300) {





  
  

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  img = check_ants(img)





  
  

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  # just get rid of the standard background just in case





  
  

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  bg_mask = iMath(img < -950, "GetLargestComponent")





  
  

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  mask = maskImage(img > -1023 & img < -900, 1 - bg_mask)





  
  

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  ind = which(as.array(mask) > 0, arr.ind = TRUE)





  
  

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  seed = floor(colMeans(ind))





  
  

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  d = colMeans((t(ind) - seed)^2)





  
  

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  seed = ind[which.min(d),]





  
  

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  simg = connectedThreshold(img, seed = seed, upper = lthresh, lower = -1023)





  
  

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}