public static void DecodeQuintBlock(
ref BitStream128 bitStream,
ref IntegerSequence listIntegerEncoded,
int numberBitsPerValue)
{
ReadOnlySpan <byte> interleavedBits = new byte[] { 3, 2, 2 };
// Implement the algorithm in section C.2.12
Span <int> m = stackalloc int[3];
ulong encoded = 0;
int encodedBitsRead = 0;
for (int i = 0; i < m.Length; i++)
{
m[i] = bitStream.ReadBits(numberBitsPerValue);
uint encodedBits = (uint)bitStream.ReadBits(interleavedBits[i]);
encoded |= encodedBits << encodedBitsRead;
encodedBitsRead += interleavedBits[i];
}
ReadOnlySpan <byte> encodings = GetQuintEncoding((int)encoded);
for (int i = 0; i < 3; i++)
{
IntegerEncoded intEncoded = new IntegerEncoded(EIntegerEncoding.Quint, numberBitsPerValue)
{
BitValue = m[i],
QuintValue = encodings[i]
};
listIntegerEncoded.Add(ref intEncoded);
}
}
public static void DecodeTritBlock(
ref BitStream128 bitStream,
ref IntegerSequence listIntegerEncoded,
int numberBitsPerValue)
{
// Implement the algorithm in section C.2.12
Span <int> m = stackalloc int[5];
m[0] = bitStream.ReadBits(numberBitsPerValue);
int encoded = bitStream.ReadBits(2);
m[1] = bitStream.ReadBits(numberBitsPerValue);
encoded |= bitStream.ReadBits(2) << 2;
m[2] = bitStream.ReadBits(numberBitsPerValue);
encoded |= bitStream.ReadBits(1) << 4;
m[3] = bitStream.ReadBits(numberBitsPerValue);
encoded |= bitStream.ReadBits(2) << 5;
m[4] = bitStream.ReadBits(numberBitsPerValue);
encoded |= bitStream.ReadBits(1) << 7;
ReadOnlySpan <byte> encodings = GetTritEncoding(encoded);
IntegerEncoded intEncoded = new IntegerEncoded(EIntegerEncoding.Trit, numberBitsPerValue);
for (int i = 0; i < 5; i++)
{
intEncoded.BitValue = m[i];
intEncoded.TritValue = encodings[i];
listIntegerEncoded.Add(ref intEncoded);
}
}
public static void DecodeIntegerSequence(
ref IntegerSequence decodeIntegerSequence,
ref BitStream128 bitStream,
int maxRange,
int numberValues)
{
// Determine encoding parameters
IntegerEncoded intEncoded = CreateEncoding(maxRange);
// Start decoding
int numberValuesDecoded = 0;
while (numberValuesDecoded < numberValues)
{
switch (intEncoded.GetEncoding())
{
case EIntegerEncoding.Quint:
{
DecodeQuintBlock(ref bitStream, ref decodeIntegerSequence, intEncoded.NumberBits);
numberValuesDecoded += 3;
break;
}
case EIntegerEncoding.Trit:
{
DecodeTritBlock(ref bitStream, ref decodeIntegerSequence, intEncoded.NumberBits);
numberValuesDecoded += 5;
break;
}
case EIntegerEncoding.JustBits:
{
intEncoded.BitValue = bitStream.ReadBits(intEncoded.NumberBits);
decodeIntegerSequence.Add(ref intEncoded);
numberValuesDecoded++;
break;
}
}
}
}
