private int GetCoefficientLevelCode(int suffixLength)
{
int levelPrefix = _reader.GetLeadingZeroBits(); // level_prefix
int levelCode = (levelPrefix << suffixLength);
if ((suffixLength == 0) && (levelPrefix < 14))
{
return(levelCode); // level_suffix is (0)
}
int levelSuffixSize;
if (levelPrefix >= 15)
{
// Escape-coded (high) coefficient level
levelSuffixSize = (levelPrefix - 3);
levelCode = 15 << Math.Max(1, suffixLength);
levelCode += (1 << levelSuffixSize) - 4096;
}
else if ((levelPrefix == 14) && (suffixLength == 0))
{
levelSuffixSize = 4;
}
else
{
levelSuffixSize = suffixLength;
}
var levelSuffix = (int)_reader.GetBits(levelSuffixSize); // level_suffix
return(levelCode + levelSuffix);
}