R/emuR-parser.esps.R

In emuR: Main Package of the EMU Speech Database Management System

## Parser for ESPS label files
## 
## @param labFilePath ESPS label file path
## @param tierName name of the tier
## @param sampleRate sample rate of corresponding signal file
## @param encoding text encoding (default: NULL -> R encoding "unknown")
## @return new tier containing parsed items
## @import stringr
## @keywords emuR ESPS lab Emu
## 
parse_espsLabelFile <- function(labFilePath = NULL,
                                tierName, 
                                tierType = NULL,
                                sampleRate,
                                encoding = NULL,
                                idCnt = 0) {
  SIGNAL_KEY = "signal"
  NUMBER_OF_FIELDS_KEY = "nfields"
  SEPARATOR_KEY = "separator"
  COLOR_KEY = "color"
  DATA_SECTION_START_KEY = '#'
  INTERVAL_FLAG_VALUE = 'H#'
  
  fileToRead = NULL
  inHeaderSection = TRUE
  intervalMode = FALSE
  firstDataLine = TRUE
  intervalStart = NULL
  itemList = list()
  
  if(is.null(labFilePath)){
    stop("Argument labFilepath or labCon must not be NULL\n")
  }else{
    fileToRead = labFilePath
  }  
  if(sampleRate <= 0){
    stop("Samplerate must be greater than zero\n")
  }
  
  # read
  if(is.null(encoding)){
    lc = try(readr::read_lines(fileToRead))
  }else{
    lc = try(readr::read_lines(fileToRead,readr::locale(encoding = encoding)))
  }
  if(inherits(lc, "try-error")) {
    stop("read.esps: cannot read from file ", fileToRead)
  }
  
  for(line in lc){
    trimmedLine = stringr::str_trim(line)
    if(inHeaderSection){
      if(trimmedLine == DATA_SECTION_START_KEY){
        inHeaderSection = FALSE
      }else{
        kv = parse_lineToKeyValue(trimmedLine, '[[:space:]]')
        if(!is.null(kv) && kv[1] == NUMBER_OF_FIELDS_KEY){
          if(kv[2] != 1){
            stop("only files with one field supported")
          }
        }
        # ignore other headers
      }
    }else{
      lineTokensLst = stringr::str_split(trimmedLine,'[[:space:]]+', 3)
      lineTokens = lineTokensLst[[1]]
      lineTokenCount = length(lineTokens);
      if(lineTokenCount >= 2){
        
        timeStampStr = lineTokens[1]
        color = lineTokens[2]
        label = NULL
        if(lineTokenCount == 3){
          label = lineTokens[3]
        }
        
        timeStamp = as(timeStampStr,"numeric")
        timeStampInSamples = timeStamp*sampleRate
        if(firstDataLine){
          
          if(is.null(tierType)){
            if(label == INTERVAL_FLAG_VALUE){
              tierType = 'SEGMENT'
            }else{
              tierType = 'EVENT'
            }
          }
        }
        
        if(firstDataLine & tierType == 'SEGMENT'){
          samplePoint = floor(timeStampInSamples)
          intervalStartPoint = samplePoint
        }else{
          lblVal = ''
          if(!is.null(label)){
            lblVal = label
          }
          labelAttrs = list(list(name = tierName, 
                                 value = lblVal))
          #labelAttrs[[tierName]]=label
          
          if(tierType == 'SEGMENT'){
            samplePoint = floor(timeStampInSamples)
            # duration calculation according to partitur format
            # the sum of all durations is not equal to the complete sample count
            duration = samplePoint - intervalStartPoint - 1
            currItem = list(id = idCnt,
                            sampleStart = intervalStartPoint,
                            sampleDur = duration,
                            labels = labelAttrs)
            idCnt = idCnt + 1
            itemList[[length(itemList) + 1]] <- currItem
            intervalStartPoint = samplePoint
            
          }else{
            samplePoint = round(timeStampInSamples)
            currItem=list(id = idCnt,
                          samplePoint = samplePoint,
                          labels = labelAttrs)
            idCnt = idCnt + 1
            itemList[[length(itemList) + 1]] <- currItem
          }
          
        }
        firstDataLine = FALSE
      }
    }
  }
  labTier = list(name = tierName,
                 type = tierType, 
                 sampleRate = sampleRate,
                 items = itemList)
  return(labTier)
}