public async Task<OpticalReaderLib.EnhanceResult> EnhanceAsync(OpticalReaderLib.Frame frame)
{
if (frame.Format == OpticalReaderLib.FrameFormat.Gray8)
{
_threshold = _threshold + _jump;
if (_threshold > _max)
{
_threshold = _min;
}
var f = await Task.Run<OpticalReaderLib.Frame>(() =>
{
for (int i = 0; i < frame.Buffer.Length; i++)
{
frame.Buffer[i] = (byte)(frame.Buffer[i] < _threshold ? 0x00 : 0xff);
}
return frame;
});
return new OpticalReaderLib.EnhanceResult()
{
Frame = f
};
}
else
{
throw new Exception("Dumb little custom enhancer only supports Gray8 encoded frames");
}
}
private async Task<Tuple<ProcessResult, WriteableBitmap>> ProcessFrameAsync(OpticalReaderLib.Frame frame)
{
//System.Diagnostics.Debug.WriteLine("Start processing");
var rectSize = new Windows.Foundation.Size(
ReaderBorder.ActualWidth / Canvas.ActualWidth * frame.Dimensions.Width / _zoom,
ReaderBorder.ActualHeight / Canvas.ActualHeight * frame.Dimensions.Height / _zoom);
var rectOrigin = new Windows.Foundation.Point(
frame.Dimensions.Width / 2 - rectSize.Width / 2,
frame.Dimensions.Height / 2 - rectSize.Height / 2);
var area = new Windows.Foundation.Rect(rectOrigin, rectSize);
ProcessResult result = null;
try
{
result = await OpticalReaderTask.Instance.Processor.ProcessAsync(frame, area, _rotation);
}
catch (Exception ex)
{
System.Diagnostics.Debug.WriteLine(String.Format("Processing frame failed: {0}\n{1}", ex.Message, ex.StackTrace));
}
//System.Diagnostics.Debug.WriteLine("Stop processing");
InterestAreaPolygon.Points = null;
if (result != null)
{
_lastSuccess = DateTime.Now;
var thumbnail = GenerateThumbnail();
var interestPointCollection = new PointCollection();
foreach (var point in result.InterestPoints)
{
interestPointCollection.Add(new System.Windows.Point(point.X, point.Y));
}
InterestAreaPolygon.Points = interestPointCollection;
return new Tuple<ProcessResult, WriteableBitmap>(result, thumbnail);
}
else
{
var sinceLastSuccess = DateTime.Now - _lastSuccess;
if (sinceLastSuccess > OpticalReaderTask.Instance.FocusInterval)
{
try
{
var status = await _device.FocusAsync();
_lastSuccess = DateTime.Now;
// todo use camera focus lock status
}
catch (Exception ex)
{
System.Diagnostics.Debug.WriteLine(String.Format("Focusing camera failed: {0}\n{1}", ex.Message, ex.StackTrace));
}
}
return null;
}
}
private void OpticalReaderTask_Completed(object sender, OpticalReaderLib.OpticalReaderResult e)
{
_taskResult = e;
}
