C# FNV1a32 XOR Folding Version

FNV1a32xf.cs

/// <summary>
/// XOR folding version reduces collisions by greater than ~2/3's
/// </summary>
public class FNV1a32 : HashAlgorithm
{
    private const uint K = 0x1000193;
    private       uint _hash;
    public        uint Hash;
    public        uint Seed = 0x811c9dc5;
    public FNV1a32()
    {
        _hash = Seed;
    }
    public FNV1a32(uint seed)
    {
        Seed  = seed;
        _hash = Seed;
    }
    public override int HashSize => 32;
    public override void Initialize()
    {
        _hash = Seed;
    }
    protected override void HashCore(byte[] bytes, int ibStart, int cbSize)
    {
        Hash32(bytes, ibStart, cbSize);
    }
    private void Hash32(byte[] bytes, int ibStart, int cbSize)
    {
        if(bytes == null)
            return;
        if(ibStart >= bytes.Length || cbSize > bytes.Length)
            return;
        var ohLen = cbSize >> 1;
        var h1 = _hash;
        for (var i = ibStart; i < ohLen; i++)
            h1 = (h1 ^ bytes[i]) * K;
        var h2 = h1;
        for (var i = ibStart+ ohLen; i < cbSize; i++)
            h2 = (h2 ^ bytes[i]) * K;
        h1 ^= (uint)cbSize;
        h2 ^= (uint)cbSize;
        _hash = (h1 >> 24) ^ (h2 & 0xffffffff);
    }
    /// <summary>
    ///     Exposed so that hash64 can be used externally.
    /// </summary>
    public uint Hash32(byte[] bytes)
    {
        var cbSize = bytes.Length;
        var ohLen = cbSize >> 1;
        _hash = Seed;
        var h1 = _hash;
        for(var i = 0; i < ohLen; i++)
            h1 = (h1 ^ bytes[i]) * K;
        var h2 = h1;
        for(var i = ohLen; i < cbSize; i++)
            h2 = (h2 ^ bytes[i]) * K;
        h1 ^= (uint)cbSize;
        h2 ^= (uint)cbSize;
        _hash = (h1 >> 24) ^ (h2 & 0xffffffff);
        return _hash;
    }
    protected override byte[] HashFinal()
    {
        Hash = _hash;
        return _hash.GetBytes();
    }
}