async Task <Video> Analyze(string path) => await Task.Run(() =>
{
try
{
BlobCountingObjectsProcessing processingAlgorithm = new BlobCountingObjectsProcessing()
{
MinObjectsHeight = 35,
MinObjectsWidth = 35
};
MotionDetector detector = new MotionDetector(new TwoFramesDifferenceDetector(), processingAlgorithm);
VideoFileReader reader = new VideoFileReader();
List <Segment> markers = new List <Segment>();
reader.Open(path); // Opens video file
progressBar.Value = 0;
Invoke(new Action(() => progressBar.Maximum = (int)(reader.FrameCount / reader.FrameRate - 1)));
bool isMoving = false;
Segment temp = new Segment();
//Algorythm
for (int k = 1; k < (int)(reader.FrameCount / reader.FrameRate); k++) // Loop processes every second
{
for (int step = 0; step < 2; step++) // Processes two halfs of the current second
{
detector.ProcessFrame(reader.ReadVideoFrame()); // Processes frame
for (int i = 1; i < (int)(reader.FrameRate / 2); i++) // Skips other frames
{
reader.ReadVideoFrame();
}
}
GC.Collect(); // Releases memory
if (processingAlgorithm.ObjectsCount > 0 && !isMoving) // If there's any new moving object - creates new segment
{
isMoving = true;
temp.Start = k - 1;
}
else if (processingAlgorithm.ObjectsCount == 0 && isMoving) // If there's both opened segment and no moving objects - closes segment
{
isMoving = false;
temp.End = k;
markers.Add(temp);
temp = new Segment();
}
Invoke(new Action(() => // Updates progress bar
{
progressBar.Value++;
percentage.Text = $"{Math.Round((float)progressBar.Value / progressBar.Maximum * 100)}%";
}));
cts.Token.ThrowIfCancellationRequested();
}
// Markers post-processing
for (int k = 0; k < markers.Count; k++)
{
if (markers[k].Duration < 3) // Deletes segments if they last less than 3 seconds
{
markers.RemoveAt(k--);
}
}
for (int k = 1; k < markers.Count; k++)
{
if (Segment.AbsoluteDistanceBetweenSegments(markers[k - 1], markers[k]) <= 5)
{
markers[k - 1].End = markers[k].End; // Joins two segments if between them is less than 5 seconds
markers.RemoveAt(k--);
}
}
Video video = new Video()
{
Path = path,
Name = new FileInfo(path).Name,
Markers = markers
};
// Writing data to disk
File.WriteAllText(path + ".data", JsonConvert.SerializeObject(video));
return(video);
}
catch (OperationCanceledException)
{
cts = new CancellationTokenSource();
return(null);
}
catch (Exception e)
{
MessageBox.Show(e.Message, e.GetType().ToString(), MessageBoxButtons.OK, MessageBoxIcon.Error);
return(null);
}
});
