private void bw_DoWork(object sender, DoWorkEventArgs e)
{
BackgroundWorker worker = sender as BackgroundWorker;
Parameters parameters = (Parameters)e.Argument;
var streams = parameters.SourceFiles.Select(fi => AudioStreamFactory.FromFileInfo(fi));
// load source stream
var sourceStream = new ConcatenationStream(streams.ToArray());
var firstFile = parameters.SourceFiles.First();
string targetFileNamePrefix = firstFile.FullName.Remove(firstFile.FullName.Length - firstFile.Extension.Length);
string targetFileNameSuffix = firstFile.Extension;
int partCount = 0;
Random random = new Random();
CropStream cropStream = new CropStream(sourceStream, 0, 0);
while (sourceStream.Position < sourceStream.Length)
{
partCount++;
int length = random.Next(parameters.MinLength, parameters.MaxLength); // length in seconds of the current part to write
long byteLength = TimeUtil.TimeSpanToBytes(new TimeSpan(TimeUtil.SECS_TO_TICKS * length), cropStream.Properties);
Debug.WriteLine("writing part " + partCount + " (" + length + " secs = " + byteLength + " bytes)");
Debug.WriteLine("before: " + cropStream.Begin + " / " + cropStream.End + " / " + cropStream.Position + " / " + sourceStream.Position);
cropStream.Begin = cropStream.End;
cropStream.End += sourceStream.Length - cropStream.Begin < byteLength ? sourceStream.Length - cropStream.Begin : byteLength;
cropStream.Position = 0;
Debug.WriteLine("after : " + cropStream.Begin + " / " + cropStream.End + " / " + cropStream.Position + " / " + sourceStream.Position);
AudioStreamFactory.WriteToFile(cropStream, String.Format("{0}.part{1:000}{2}", targetFileNamePrefix, partCount, targetFileNameSuffix));
if (worker.CancellationPending)
{
e.Cancel = true;
Debug.WriteLine("canceled");
return;
}
worker.ReportProgress((int)((double)sourceStream.Position / sourceStream.Length * 100));
}
Debug.WriteLine("finished");
}
private void TimeWarp(TimeWarpType type, AudioTrack t1, TimeSpan t1From, TimeSpan t1To, AudioTrack t2, TimeSpan t2From, TimeSpan t2To, bool calculateSimilarity, bool normalizeSimilarity, bool cueIn, bool cueOut)
{
IAudioStream s1 = t1.CreateAudioStream();
IAudioStream s2 = t2.CreateAudioStream();
s1 = new CropStream(s1, TimeUtil.TimeSpanToBytes(t1From, s1.Properties), TimeUtil.TimeSpanToBytes(t1To, s1.Properties));
s2 = new CropStream(s2, TimeUtil.TimeSpanToBytes(t2From, s2.Properties), TimeUtil.TimeSpanToBytes(t2To, s2.Properties));
List <Tuple <TimeSpan, TimeSpan> > path = null;
DTW dtw = null;
// execute time warping
if (type == TimeWarpType.DTW)
{
dtw = new DTW(TimeWarpSearchWidth, progressMonitor);
}
else if (type == TimeWarpType.OLTW)
{
dtw = new OLTW2(TimeWarpSearchWidth, progressMonitor);
}
if (TimeWarpDisplay)
{
this.Dispatcher.BeginInvoke((Action) delegate {
dtwPathViewer = new DtwPathViewer();
dtwPathViewer.Show();
});
dtw.OltwInit += new DTW.OltwInitDelegate(delegate(int windowSize, IMatrix <double> cellCostMatrix, IMatrix <double> totalCostMatrix) {
dtwPathViewer.Dispatcher.BeginInvoke((Action) delegate {
dtwPathViewer.DtwPath.Init(windowSize, cellCostMatrix, totalCostMatrix);
});
});
bool drawing = false;
dtw.OltwProgress += new DTW.OltwProgressDelegate(delegate(int i, int j, int minI, int minJ, bool force) {
if (!drawing || force)
{
dtwPathViewer.Dispatcher.BeginInvoke((Action) delegate {
drawing = true;
dtwPathViewer.DtwPath.Refresh(i, j, minI, minJ);
drawing = false;
});
}
});
}
path = dtw.Execute(s1, s2);
if (path == null)
{
return;
}
// convert resulting path to matches and filter them
int filterSize = TimeWarpFilterSize; // take every n-th match and drop the rest
bool smoothing = TimeWarpSmoothing;
int smoothingWidth = Math.Max(1, Math.Min(filterSize / 10, filterSize));
bool inOutCue = TimeWarpInOutCue;
TimeSpan inOutCueSpan = TimeWarpSearchWidth;
List <Match> matches = new List <Match>();
float maxSimilarity = 0; // needed for normalization
IProgressReporter progressReporter = progressMonitor.BeginTask("post-process resulting path...", true);
double totalProgress = path.Count;
double progress = 0;
/* Leave out matches in the in/out cue areas...
* The matches in the interval at the beginning and end of the calculated time warping path with a width
* equal to the search width should be left out because they might not be correct - since the time warp
* path needs to start at (0,0) in the matrix and end at (m,n), they would only be correct if the path gets
* calculated between two synchronization points. Paths calculated from the start of a track to the first
* sync point, or from the last sync point to end of the track are probably wrong in this interval since
* the start and end points don't match if there is time drift so it is better to leave them out in those
* areas... in those short a few second long intervals the drict actually will never be that extreme that
* someone would notice it anyway. */
if (inOutCue)
{
int startIndex = 0;
int endIndex = path.Count;
// this needs a temporally ordered mapping path (no matter if ascending or descending)
foreach (Tuple <TimeSpan, TimeSpan> mapping in path)
{
if (cueIn && (mapping.Item1 < inOutCueSpan || mapping.Item2 < inOutCueSpan))
{
startIndex++;
}
if (cueOut && (mapping.Item1 > (t1To - t1From - inOutCueSpan) || mapping.Item2 > (t2To - t2From - inOutCueSpan)))
{
endIndex--;
}
}
path = path.GetRange(startIndex, endIndex - startIndex);
}
for (int i = 0; i < path.Count; i += filterSize)
{
//List<Tuple<TimeSpan, TimeSpan>> section = path.GetRange(i, Math.Min(path.Count - i, filterSize));
List <Tuple <TimeSpan, TimeSpan> > smoothingSection = path.GetRange(
Math.Max(0, i - smoothingWidth / 2), Math.Min(path.Count - i, smoothingWidth));
Tuple <TimeSpan, TimeSpan> match = path[i];
if (smoothingSection.Count == 0)
{
throw new InvalidOperationException("must not happen");
}
else if (smoothingSection.Count == 1 || !smoothing || i == 0)
{
// do nothing, match doesn't need any processing
// the first and last match must not be smoothed since they must sit at the bounds
}
else
{
List <TimeSpan> offsets = new List <TimeSpan>(smoothingSection.Select(t => t.Item2 - t.Item1).OrderBy(t => t));
int middle = offsets.Count / 2;
// calculate median
// http://en.wikiversity.org/wiki/Primary_mathematics/Average,_median,_and_mode#Median
TimeSpan smoothedDriftTime = new TimeSpan((offsets[middle - 1] + offsets[middle]).Ticks / 2);
match = new Tuple <TimeSpan, TimeSpan>(match.Item1, match.Item1 + smoothedDriftTime);
}
float similarity = calculateSimilarity ? (float)Math.Abs(CrossCorrelation.Correlate(
s1, new Interval(match.Item1.Ticks, match.Item1.Ticks + TimeUtil.SECS_TO_TICKS),
s2, new Interval(match.Item2.Ticks, match.Item2.Ticks + TimeUtil.SECS_TO_TICKS))) : 1;
if (similarity > maxSimilarity)
{
maxSimilarity = similarity;
}
matches.Add(new Match()
{
Track1 = t1,
Track1Time = match.Item1 + t1From,
Track2 = t2,
Track2Time = match.Item2 + t2From,
Similarity = similarity,
Source = type.ToString()
});
progressReporter.ReportProgress(progress / totalProgress * 100);
progress += filterSize;
}
// add last match if it hasn't been added
if (path.Count > 0 && path.Count % filterSize != 1)
{
Tuple <TimeSpan, TimeSpan> lastMatch = path[path.Count - 1];
matches.Add(new Match()
{
Track1 = t1,
Track1Time = lastMatch.Item1 + t1From,
Track2 = t2,
Track2Time = lastMatch.Item2 + t2From,
Similarity = 1,
Source = type.ToString()
});
}
progressReporter.Finish();
multiTrackViewer.Dispatcher.BeginInvoke((Action) delegate {
foreach (Match match in matches)
{
if (normalizeSimilarity)
{
match.Similarity /= maxSimilarity; // normalize to 1
}
multiTrackViewer.Matches.Add(match);
}
});
s1.Close();
s2.Close();
}
