function getTagValue(tagCode, map, dataView, offset, length) {
    if (map.types[tagCode] === 'binary') {
      return new Blob([dataView.buffer.slice(offset, offset + length)])
    }
    if (map.types[tagCode] === 'Uint16') {
      return dataView.getUint16(offset)
    }
    return getStringValue(dataView, offset, length)
  }
Retrieves tag value for the given DataView and range

@param {number} tagCode tag code
@param {IptcMap} map IPTC tag map
@param {DataView} dataView Data view interface
@param {number} offset Range start
@param {number} length Range length
@returns {object} Tag value