foundPatternCross static method

bool foundPatternCross(List<int> stateCount)

@param stateCount count of black/white/black/white/black pixels just read @return true iff the proportions of the counts is close enough to the 1/1/3/1/1 ratios used by finder patterns to be considered a match

Implementation

//@protected
static bool foundPatternCross(List<int> stateCount) {
  int totalModuleSize = 0;
  for (int i = 0; i < 5; i++) {
    final count = stateCount[i];
    if (count == 0) {
      return false;
    }
    totalModuleSize += count;
  }
  if (totalModuleSize < 7) {
    return false;
  }
  final moduleSize = totalModuleSize / 7.0;
  final maxVariance = moduleSize / 2.0;
  // Allow less than 50% variance from 1-1-3-1-1 proportions
  return (moduleSize - stateCount[0]).abs() < maxVariance &&
      (moduleSize - stateCount[1]).abs() < maxVariance &&
      (3.0 * moduleSize - stateCount[2]).abs() < 3 * maxVariance &&
      (moduleSize - stateCount[3]).abs() < maxVariance &&
      (moduleSize - stateCount[4]).abs() < maxVariance;
}