/// <summary>
///
/// </summary>
/// <param name="image"></param>
/// <param name="winStride"></param>
/// <param name="locations"></param>
/// <returns></returns>
public float[] Compute(Image<Gray, Byte> image, Size winStride, Point[] locations)
{
using (VectorOfFloat vof = new VectorOfFloat())
{
GCHandle handle = GCHandle.Alloc(locations, GCHandleType.Pinned);
CvSelfSimDescriptorCompute(_ptr, image, vof, ref winStride, handle.AddrOfPinnedObject(), locations.Length);
handle.Free();
return vof.ToArray();
}
}
/*
* public static void TestDrawLine(IntPtr img, int startX, int startY, int endX, int endY, MCvScalar color)
* {
* TestDrawLine(img, startX, startY, endX, endY, color.v0, color.v1, color.v2, color.v3);
* }
*
* [DllImport(CvInvoke.EXTERN_LIBRARY, CallingConvention = CvInvoke.CvCallingConvention, EntryPoint="testDrawLine")]
* private static extern void TestDrawLine(IntPtr img, int startX, int startY, int endX, int endY, double v0, double v1, double v2, double v3);
*/
/// <summary>
/// Implements the chamfer matching algorithm on images taking into account both distance from
/// the template pixels to the nearest pixels and orientation alignment between template and image
/// contours.
/// </summary>
/// <param name="img">The edge image where search is performed</param>
/// <param name="templ">The template (an edge image)</param>
/// <param name="contours">The output contours</param>
/// <param name="cost">The cost associated with the matching</param>
/// <param name="templScale">The template scale, use 1 for default</param>
/// <param name="maxMatches">The maximum number of matches, use 20 for default</param>
/// <param name="minMatchDistance">The minimum match distance. use 1.0 for default</param>
/// <param name="padX">PadX, use 3 for default</param>
/// <param name="padY">PadY, use 3 for default</param>
/// <param name="scales">Scales, use 5 for default</param>
/// <param name="minScale">Minimum scale, use 0.6 for default</param>
/// <param name="maxScale">Maximum scale, use 1.6 for default</param>
/// <param name="orientationWeight">Orientation weight, use 0.5 for default</param>
/// <param name="truncate">Truncate, use 20 for default</param>
/// <returns>The number of matches</returns>
public static int cvChamferMatching(Image <Gray, Byte> img, Image <Gray, Byte> templ,
out Point[][] contours, out float[] cost,
double templScale, int maxMatches,
double minMatchDistance, int padX,
int padY, int scales, double minScale, double maxScale,
double orientationWeight, double truncate)
{
using (Emgu.CV.Util.VectorOfVectorOfPoint vecOfVecOfPoint = new Util.VectorOfVectorOfPoint())
using (Emgu.CV.Util.VectorOfFloat vecOfFloat = new Util.VectorOfFloat())
{
int count = _cvChamferMatching(img, templ, vecOfVecOfPoint, vecOfFloat, templScale, maxMatches, minMatchDistance, padX, padY, scales, minScale, maxScale, orientationWeight, truncate);
contours = vecOfVecOfPoint.ToArray();
cost = vecOfFloat.ToArray();
return(count);
}
}
/// <summary>
/// Calculates optical flow for a sparse feature set using iterative Lucas-Kanade method in pyramids
/// </summary>
/// <param name="prev">First frame, at time t</param>
/// <param name="curr">Second frame, at time t + dt </param>
/// <param name="prevFeatures">Array of points for which the flow needs to be found</param>
/// <param name="winSize">Size of the search window of each pyramid level</param>
/// <param name="level">Maximal pyramid level number. If 0 , pyramids are not used (single level), if 1 , two levels are used, etc</param>
/// <param name="criteria">Specifies when the iteration process of finding the flow for each point on each pyramid level should be stopped</param>
/// <param name="flags">Flags</param>
/// <param name="currFeatures">Array of 2D points containing calculated new positions of input features in the second image</param>
/// <param name="status">Array. Every element of the array is set to 1 if the flow for the corresponding feature has been found, 0 otherwise</param>
/// <param name="trackError">Array of double numbers containing difference between patches around the original and moved points</param>
/// <param name="minEigThreshold">the algorithm calculates the minimum eigen value of a 2x2 normal matrix of optical flow equations (this matrix is called a spatial gradient matrix in [Bouguet00]), divided by number of pixels in a window; if this value is less than minEigThreshold, then a corresponding feature is filtered out and its flow is not processed, so it allows to remove bad points and get a performance boost.</param>
public static void CalcOpticalFlowPyrLK(
IInputArray prev,
IInputArray curr,
PointF[] prevFeatures,
Size winSize,
int level,
MCvTermCriteria criteria,
out PointF[] currFeatures,
out Byte[] status,
out float[] trackError,
Emgu.CV.CvEnum.LKFlowFlag flags = CvEnum.LKFlowFlag.Default,
double minEigThreshold = 1.0e-4)
{
using (Util.VectorOfPointF prevPts = new Util.VectorOfPointF())
using (Util.VectorOfPointF nextPts = new Util.VectorOfPointF())
using (Util.VectorOfByte statusVec = new Util.VectorOfByte())
using (Util.VectorOfFloat errorVec = new Util.VectorOfFloat())
{
prevPts.Push(prevFeatures);
CalcOpticalFlowPyrLK(
prev,
curr,
prevPts,
nextPts,
statusVec,
errorVec,
winSize,
level,
criteria,
flags,
minEigThreshold);
status = statusVec.ToArray();
trackError = errorVec.ToArray();
currFeatures = nextPts.ToArray();
}
}
/*
#region Kalman Filter
/// <summary>
/// Allocates CvKalman and all its matrices and initializes them somehow.
/// </summary>
/// <param name="dynamParams">dimensionality of the state vector</param>
/// <param name="measureParams">dimensionality of the measurement vector </param>
/// <param name="controlParams">dimensionality of the control vector </param>
/// <returns>Pointer to the created Kalman filter</returns>
[DllImport(OpencvVideoLibrary, CallingConvention = CvInvoke.CvCallingConvention)]
public static extern IntPtr cvCreateKalman(int dynamParams, int measureParams, int controlParams);
/// <summary>
/// Adjusts stochastic model state on the basis of the given measurement of the model state.
/// The function stores adjusted state at kalman->state_post and returns it on output
/// </summary>
/// <param name="kalman">Pointer to the structure to be updated</param>
/// <param name="measurement">Pointer to the structure CvMat containing the measurement vector</param>
/// <returns>The function stores adjusted state at kalman->state_post and returns it on output</returns>
[DllImport(OpencvVideoLibrary, CallingConvention = CvInvoke.CvCallingConvention)]
public static extern IntPtr cvKalmanCorrect(ref MCvKalman kalman, IntPtr measurement);
/// <summary>
/// Estimates the subsequent stochastic model state by its current state and stores it at kalman->state_pre
/// The function returns the estimated state
/// </summary>
/// <param name="kalman">Kalman filter state</param>
/// <param name="control">Control vector (uk), should be NULL iff there is no external control (controlParams=0). </param>
/// <returns>the estimated state</returns>
[DllImport(OpencvVideoLibrary, CallingConvention = CvInvoke.CvCallingConvention)]
public static extern IntPtr cvKalmanPredict(ref MCvKalman kalman, IntPtr control);
/// <summary>
/// Releases the structure CvKalman and all underlying matrices
/// </summary>
/// <param name="kalman">reference of the pointer to the Kalman filter structure.</param>
[DllImport(OpencvVideoLibrary, CallingConvention = CvInvoke.CvCallingConvention)]
public static extern void cvReleaseKalman(ref IntPtr kalman);
#endregion
*/
#region optical flow
/// <summary>
/// Calculates optical flow for a sparse feature set using iterative Lucas-Kanade method in pyramids
/// </summary>
/// <param name="prev">First frame, at time t</param>
/// <param name="curr">Second frame, at time t + dt </param>
/// <param name="prevFeatures">Array of points for which the flow needs to be found</param>
/// <param name="winSize">Size of the search window of each pyramid level</param>
/// <param name="level">Maximal pyramid level number. If 0 , pyramids are not used (single level), if 1 , two levels are used, etc</param>
/// <param name="criteria">Specifies when the iteration process of finding the flow for each point on each pyramid level should be stopped</param>
/// <param name="flags">Flags</param>
/// <param name="currFeatures">Array of 2D points containing calculated new positions of input features in the second image</param>
/// <param name="status">Array. Every element of the array is set to 1 if the flow for the corresponding feature has been found, 0 otherwise</param>
/// <param name="trackError">Array of double numbers containing difference between patches around the original and moved points</param>
/// <param name="minEigThreshold">the algorithm calculates the minimum eigen value of a 2x2 normal matrix of optical flow equations (this matrix is called a spatial gradient matrix in [Bouguet00]), divided by number of pixels in a window; if this value is less than minEigThreshold, then a corresponding feature is filtered out and its flow is not processed, so it allows to remove bad points and get a performance boost.</param>
public static void CalcOpticalFlowPyrLK(
IInputArray prev,
IInputArray curr,
PointF[] prevFeatures,
Size winSize,
int level,
MCvTermCriteria criteria,
out PointF[] currFeatures,
out Byte[] status,
out float[] trackError,
Emgu.CV.CvEnum.LKFlowFlag flags = CvEnum.LKFlowFlag.Default,
double minEigThreshold = 1.0e-4)
{
using (Util.VectorOfPointF prevPts = new Util.VectorOfPointF())
using (Util.VectorOfPointF nextPts = new Util.VectorOfPointF())
using (Util.VectorOfByte statusVec = new Util.VectorOfByte())
using (Util.VectorOfFloat errorVec = new Util.VectorOfFloat())
{
prevPts.Push(prevFeatures);
CalcOpticalFlowPyrLK(
prev,
curr,
prevPts,
nextPts,
statusVec,
errorVec,
winSize,
level,
criteria,
flags,
minEigThreshold);
status = statusVec.ToArray();
trackError = errorVec.ToArray();
currFeatures = nextPts.ToArray();
}
}
/// <summary>
/// Compute the descriptor given the image and the point location
/// </summary>
/// <param name="image">The image where the descriptor will be computed from</param>
/// <param name="mask">The optional mask, can be null if not needed</param>
/// <param name="keyPoints">The keypoint where the descriptor will be computed from</param>
/// <returns>The image features founded on the keypoint location</returns>
public ImageFeature[] ComputeDescriptors(Image<Gray, Byte> image, Image<Gray, byte> mask, MKeyPoint[] keyPoints)
{
if (keyPoints.Length == 0) return new ImageFeature[0];
using (VectorOfFloat descVec = new VectorOfFloat())
using (VectorOfKeyPoint kpts = new VectorOfKeyPoint())
{
kpts.Push(keyPoints);
CvSIFTDetectorComputeDescriptors(_ptr, image, mask, kpts, descVec);
int n = keyPoints.Length;
float[] descs = descVec.ToArray();
//long address = descVec.StartAddress.ToInt64();
ImageFeature[] features = new ImageFeature[n];
int sizeOfdescriptor = DescriptorSize;
for (int i = 0; i < n; i++)
{
features[i].KeyPoint = keyPoints[i];
float[] d = new float[sizeOfdescriptor];
Array.Copy(descs, i * sizeOfdescriptor, d, 0, sizeOfdescriptor);
features[i].Descriptor = d;
}
return features;
}
}
/// <summary>
/// Detect image features from the given image
/// </summary>
/// <param name="image">The image to detect features from</param>
/// <param name="mask">The optional mask, can be null if not needed</param>
/// <returns>The Image features detected from the given image</returns>
public ImageFeature[] DetectFeatures(Image<Gray, Byte> image, Image<Gray, byte> mask)
{
using (VectorOfKeyPoint pts = new VectorOfKeyPoint())
using (VectorOfFloat descVec = new VectorOfFloat())
{
CvSIFTDetectorDetectFeature(_ptr, image, mask, pts, descVec);
MKeyPoint[] kpts = pts.ToArray();
float[] desc = descVec.ToArray();
int n = kpts.Length;
int sizeOfdescriptor = DescriptorSize;
ImageFeature[] features = new ImageFeature[n];
for (int i = 0; i < n; i++)
{
features[i].KeyPoint = kpts[i];
float[] d = new float[sizeOfdescriptor];
Array.Copy(desc, i * sizeOfdescriptor, d, 0, sizeOfdescriptor);
features[i].Descriptor = d;
}
return features;
}
}
/*
public static void TestDrawLine(IntPtr img, int startX, int startY, int endX, int endY, MCvScalar color)
{
TestDrawLine(img, startX, startY, endX, endY, color.v0, color.v1, color.v2, color.v3);
}
[DllImport(CvInvoke.EXTERN_LIBRARY, CallingConvention = CvInvoke.CvCallingConvention, EntryPoint="testDrawLine")]
private static extern void TestDrawLine(IntPtr img, int startX, int startY, int endX, int endY, double v0, double v1, double v2, double v3);
*/
/// <summary>
/// Implements the chamfer matching algorithm on images taking into account both distance from
/// the template pixels to the nearest pixels and orientation alignment between template and image
/// contours.
/// </summary>
/// <param name="img">The edge image where search is performed</param>
/// <param name="templ">The template (an edge image)</param>
/// <param name="contours">The output contours</param>
/// <param name="cost">The cost associated with the matching</param>
/// <param name="templScale">The template scale, use 1 for default</param>
/// <param name="maxMatches">The maximum number of matches, use 20 for default</param>
/// <param name="minMatchDistance">The minimum match distance. use 1.0 for default</param>
/// <param name="padX">PadX, use 3 for default</param>
/// <param name="padY">PadY, use 3 for default</param>
/// <param name="scales">Scales, use 5 for default</param>
/// <param name="minScale">Minimum scale, use 0.6 for default</param>
/// <param name="maxScale">Maximum scale, use 1.6 for default</param>
/// <param name="orientationWeight">Orientation weight, use 0.5 for default</param>
/// <param name="truncate">Truncate, use 20 for default</param>
/// <returns>The number of matches</returns>
public static int cvChamferMatching(Image<Gray, Byte> img, Image<Gray, Byte> templ,
out Point[][] contours, out float[] cost,
double templScale, int maxMatches,
double minMatchDistance, int padX,
int padY, int scales, double minScale, double maxScale,
double orientationWeight, double truncate)
{
using (Emgu.CV.Util.VectorOfVectorOfPoint vecOfVecOfPoint = new Util.VectorOfVectorOfPoint())
using (Emgu.CV.Util.VectorOfFloat vecOfFloat = new Util.VectorOfFloat())
{
int count = _cvChamferMatching(img, templ, vecOfVecOfPoint, vecOfFloat, templScale, maxMatches, minMatchDistance, padX, padY, scales, minScale, maxScale, orientationWeight, truncate);
contours = vecOfVecOfPoint.ToArray();
cost = vecOfFloat.ToArray();
return count;
}
}