decodeVersionInformation static method

Version? decodeVersionInformation(int versionBits)

Implementation

static Version? decodeVersionInformation(int versionBits) {
  int bestDifference = MathUtils.maxValue; // int.max
  int bestVersion = 0;
  for (int i = 0; i < _versionDecodeInfo.length; i++) {
    final targetVersion = _versionDecodeInfo[i];
    // Do the version info bits match exactly? done.
    if (targetVersion == versionBits) {
      return getVersionForNumber(i + 7);
    }
    // Otherwise see if this is the closest to a real version info bit string
    // we have seen so far
    final bitsDifference =
        FormatInformation.numBitsDiffering(versionBits, targetVersion);
    if (bitsDifference < bestDifference) {
      bestVersion = i + 7;
      bestDifference = bitsDifference;
    }
  }
  // We can tolerate up to 3 bits of error since no two version info codewords will
  // differ in less than 8 bits.
  if (bestDifference <= 3) {
    return getVersionForNumber(bestVersion);
  }
  // If we didn't find a close enough match, fail
  return null;
}