/// <summary>
/// Insert hash into the RAM Storage. Be careful, there should be a Track object already inserted into the Storage.
/// </summary>
/// <param name = "hash">Hash signature that corresponds to a specific track</param>
/// <param name = "type">Type of the hash to be inserted</param>
public void InsertHash(HashSignature hash, HashType type)
{
switch (type)
{
case HashType.Query:
_fingerprints[hash.Track].Query.Add(hash);
break;
case HashType.Creational:
{
_fingerprints[hash.Track].Creational.Add(hash);
int[] signature = hash.Signature;
lock (_hashTables.SyncRoot) /*Lock insertion in the hash-tables as it keys are verified*/
{
for (int i = 0; i < _numberOfHashTables; i++)
{
if (!_hashTables[i].ContainsKey(signature[i]))
{
_hashTables[i][signature[i]] = new HashSet <Track>();
}
_hashTables[i][signature[i]].Add(hash.Track);
}
}
}
break;
}
}
// ReSharper disable ReturnTypeCanBeEnumerable.Local
private List <HashSignature> GetSignatures(IEnumerable <bool[]> fingerprints, Track track, int hashTables, int hashKeys)
// ReSharper restore ReturnTypeCanBeEnumerable.Local
{
List <HashSignature> signatures = new List <HashSignature>();
foreach (bool[] fingerprint in fingerprints)
{
int[] signature = _hasher.ComputeMinHashSignature(fingerprint); /*Compute min-hash signature out of fingerprint*/
Dictionary <int, long> buckets = _hasher.GroupMinHashToLSHBuckets(signature, hashTables, hashKeys); /*Group Min-Hash signature into LSH buckets*/
int[] hashSignature = new int[buckets.Count];
foreach (KeyValuePair <int, long> bucket in buckets)
{
hashSignature[bucket.Key] = (int)bucket.Value;
}
HashSignature hash = new HashSignature(track, hashSignature); /*associate track to hash-signature*/
signatures.Add(hash);
}
return(signatures); /*Return the signatures*/
}