/// <summary>
/// A little worker that will move along the outside of the a blob and mark points
/// </summary>
/// <param name="p_point">Starting Position</param>
/// <param name="p_width">Width of the image it's tracing</param>
public ContourTracer(ref byte[] p_buffer, Point p_point, int p_width, Direction p_dir)
{
m_buffer = p_buffer;
m_curPoint = m_startPoint = p_point;
m_width = p_width;
m_curFace = m_startFace = p_dir;
m_curOffset = ImageProcess.getOffset(p_point.X, p_point.Y, p_width, 4);
m_dirValues = new int[6];
m_dirValues[(int)Direction.UP] = -p_width * 4;
m_dirValues[(int)Direction.RIGHT] = 4;
m_dirValues[(int)Direction.DOWN] = p_width * 4;
m_dirValues[(int)Direction.LEFT] = -4;
m_dirValues[0] = m_dirValues[(int)Direction.LEFT];
m_dirValues[5] = m_dirValues[(int)Direction.UP];
}
/// <summary>
/// performs the checks and movements required for that condition
/// The check is based on facing as follows
/// |_1_|_2_|_3_|
/// |_^_|
/// The caret represents facing and checks these point in sequence
/// If it is valid, contains a foreground pixel, move there and update facing, based on rules
/// </summary>
/// <param name="p_next"></param>
/// <returns>true for continue or false meaning to stop</returns>
private bool increment(ref Point p_next, int p_iterations = 0)
{
if (p_iterations == 3)
{
return(false);
}
else
{
//If the point in it's direction and counterclockwise from the current position is a valid pixel
if (m_buffer[m_curOffset + m_dirValues[(int)m_curFace] + m_dirValues[(int)m_curFace - 1]] != 0)
{
m_curOffset += m_dirValues[(int)m_curFace] + m_dirValues[(int)m_curFace - 1];
changeFacing(-1); //Face left of current facing
//I will copy this section of code becuase i don't want to have to run it up to 3 times each pixel per increment
m_curPoint = ImageProcess.getPoint(m_curOffset, m_width, 4);
p_next = m_curPoint;
}
else if (m_buffer[m_curOffset + m_dirValues[(int)m_curFace]] != 0)
{
m_curOffset += m_dirValues[(int)m_curFace];
m_curPoint = ImageProcess.getPoint(m_curOffset, m_width, 4);
p_next = m_curPoint;
}
else if (m_buffer[m_curOffset + m_dirValues[(int)m_curFace] + m_dirValues[(int)m_curFace + 1]] != 0)
{
m_curOffset += m_dirValues[(int)m_curFace] + m_dirValues[(int)m_curFace + 1];
m_curPoint = ImageProcess.getPoint(m_curOffset, m_width, 4);
p_next = m_curPoint;
}
else
{
//Turn clockwise and try again
changeFacing(1);
if (!m_curPoint.Equals(m_startPoint) || m_curFace != m_startFace)
{
return(increment(ref p_next, ++p_iterations));
}
}
//The end condition is when the tracer is on the starting position and facing the same direction
// cp == sp ^ cf == sf, perform de'morgans to get
// cp != sp | cf != sf
return(!m_curPoint.Equals(m_startPoint) || m_curFace != m_startFace);
}
}
/// <summary>
/// This updates the buffer to be representative of the datapoints
/// </summary>
/// <param name="p_dataPoints"></param>
/// <param name="p_data"></param>
/// <param name="p_buffer"></param>
public static void updateBuffer(List <Point> p_dataPoints, ref BitmapData p_data, ref byte[] p_buffer)
{
byte[] newBuffer = new byte[p_buffer.Length];
int offset;
foreach (Point point in p_dataPoints)
{
offset = ImageProcess.getOffset(point.X, point.Y, p_data.Width, 4);
newBuffer[offset] = newBuffer[offset + 1] = newBuffer[offset + 2] = 255;
}
for (offset = 3; offset < p_buffer.Length; offset += 4)
{
newBuffer[offset] = 255;
}
Buffer.BlockCopy(newBuffer, 0, p_buffer, 0, p_buffer.Length);
}
public static async void StartImageProcessing(
Action <object[]> resultCallback, Action preResultCallback,
TimeSpan?timeout, ImageProcess processMethod, bool repeat)
{
object[] result;
if (frameProcessor == null)
{
var mediaFrameSourceFinder = new MediaFrameSourceFinder();
var populated = await mediaFrameSourceFinder.PopulateAsync(
MediaFrameSourceFinder.ColorVideoPreviewFilter,
MediaFrameSourceFinder.FirstOrDefault);
if (populated)
{
// We'll take the first video capture device.
var videoCaptureDevice =
await CaptureDeviceFinder.FindFirstOrDefaultAsync();
if (videoCaptureDevice != null)
{
// Make a processor which will pull frames from the camera and run
frameProcessor = new CaptureFrameProcessor(
mediaFrameSourceFinder,
videoCaptureDevice,
MediaEncodingSubtypes.Bgra8);
// Remember to ask for auto-focus on the video capture device.
frameProcessor.SetVideoDeviceControllerInitialiser(
vd => vd.Focus.TrySetAuto(true));
}
}
}
if (frameProcessor != null)
{
isRunning = true;
await frameProcessor.ProcessFramesAsync(timeout, processMethod, repeat, resultCallback, preResultCallback);
result = frameProcessor.Result;
}
}
