majomi/intro-skipper
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

Simplify inverted indexes

Browse Source
This commit is contained in:
ConfusedPolarBear 2022-07-05 17:08:52 -05:00
parent 8a9712cfd8
commit 455b8e2c6c
4 changed files with 14 additions and 17 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

1
.gitignore vendored
View File

@ -1,5 +1,6 @@
bin/ bin/
obj/ obj/
BenchmarkDotNet.Artifacts/
# Ignore pre compiled web interface # Ignore pre compiled web interface
docker/dist docker/dist

14
ConfusedPolarBear.Plugin.IntroSkipper.Tests/TestAudioFingerprinting.cs
View File

@ -68,14 +68,14 @@ public class TestAudioFingerprinting
{ {
// 0 1 2 3 4 5 6 7 // 0 1 2 3 4 5 6 7
var fpr = new List<uint>(new uint[] { 1, 2, 3, 1, 5, 77, 42, 2 }).AsReadOnly(); var fpr = new List<uint>(new uint[] { 1, 2, 3, 1, 5, 77, 42, 2 }).AsReadOnly();
var expected = new Dictionary<uint, Collection<uint>>() var expected = new Dictionary<uint, int>()
{ {
{1, new Collection<uint>{ 0, 3 } }, {1, 3},
{2, new Collection<uint>{ 1, 7 } }, {2, 7},
{3, new Collection<uint>{ 2 } }, {3, 2},
{5, new Collection<uint>{ 4 } }, {5, 4},
{42, new Collection<uint>{ 6 } }, {42, 6},
{77, new Collection<uint>{ 5 } }, {77, 5},
}; };
var actual = Chromaprint.CreateInvertedIndex(fpr); var actual = Chromaprint.CreateInvertedIndex(fpr);

11
ConfusedPolarBear.Plugin.IntroSkipper/Chromaprint.cs
View File

@ -110,24 +110,21 @@ public static class Chromaprint
} }
/// <summary> /// <summary>
/// Transforms a Chromaprint into an inverted index of fingerprint points to the indexes they appeared at. /// Transforms a Chromaprint into an inverted index of fingerprint points to the last index it appeared at.
/// </summary> /// </summary>
/// <param name="fingerprint">Chromaprint fingerprint.</param> /// <param name="fingerprint">Chromaprint fingerprint.</param>
/// <returns>Inverted index.</returns> /// <returns>Inverted index.</returns>
public static Dictionary<uint, Collection<uint>> CreateInvertedIndex(ReadOnlyCollection<uint> fingerprint) public static Dictionary<uint, int> CreateInvertedIndex(ReadOnlyCollection<uint> fingerprint)
{ {
var invIndex = new Dictionary<uint, Collection<uint>>(); var invIndex = new Dictionary<uint, int>();
for (int i = 0; i < fingerprint.Count; i++) for (int i = 0; i < fingerprint.Count; i++)
{ {
// Get the current point. // Get the current point.
var point = fingerprint[i]; var point = fingerprint[i];
// Create a new collection for points of this value if it doesn't exist already.
invIndex.TryAdd(point, new Collection<uint>());
// Append the current sample's timecode to the collection for this point. // Append the current sample's timecode to the collection for this point.
invIndex[point].Add((uint)i); invIndex[point] = i;
} }
return invIndex; return invIndex;

5
ConfusedPolarBear.Plugin.IntroSkipper/ScheduledTasks/FingerprinterTask.cs
View File

@ -530,9 +530,8 @@ public class FingerprinterTask : IScheduledTask
if (rhsIndex.ContainsKey(point)) if (rhsIndex.ContainsKey(point))
{ {
// TODO: consider all timecodes before falling back var lhsFirst = (int)lhsIndex[point];
var lhsFirst = (int)lhsIndex[point][0]; var rhsFirst = (int)rhsIndex[point];
var rhsFirst = (int)rhsIndex[point][0];
indexShifts.Add(rhsFirst - lhsFirst); indexShifts.Add(rhsFirst - lhsFirst);
} }
} }