/// <summary>
/// computes sparse optical flow using multi-scale Lucas-Kanade algorithm
/// </summary>
/// <param name="prevImg"></param>
/// <param name="nextImg"></param>
/// <param name="prevPts"></param>
/// <param name="nextPts"></param>
/// <param name="status"></param>
/// <param name="err"></param>
/// <param name="winSize"></param>
/// <param name="maxLevel"></param>
/// <param name="criteria"></param>
/// <param name="flags"></param>
/// <param name="minEigThreshold"></param>
public static void CalcOpticalFlowPyrLK(
InputArray prevImg, InputArray nextImg,
InputArray prevPts, InputOutputArray nextPts,
OutputArray status, OutputArray err,
Size?winSize = null,
int maxLevel = 3,
TermCriteria?criteria = null,
OpticalFlowFlags flags = OpticalFlowFlags.None,
double minEigThreshold = 1e-4)
{
if (prevImg == null)
{
throw new ArgumentNullException(nameof(prevImg));
}
if (nextImg == null)
{
throw new ArgumentNullException(nameof(nextImg));
}
if (prevPts == null)
{
throw new ArgumentNullException(nameof(prevPts));
}
if (nextPts == null)
{
throw new ArgumentNullException(nameof(nextPts));
}
if (status == null)
{
throw new ArgumentNullException(nameof(status));
}
if (err == null)
{
throw new ArgumentNullException(nameof(err));
}
prevImg.ThrowIfDisposed();
nextImg.ThrowIfDisposed();
prevPts.ThrowIfDisposed();
nextPts.ThrowIfNotReady();
status.ThrowIfNotReady();
err.ThrowIfNotReady();
var winSize0 = winSize.GetValueOrDefault(new Size(21, 21));
var criteria0 = criteria.GetValueOrDefault(
TermCriteria.Both(30, 0.01));
NativeMethods.HandleException(
NativeMethods.video_calcOpticalFlowPyrLK_InputArray(
prevImg.CvPtr, nextImg.CvPtr, prevPts.CvPtr, nextPts.CvPtr,
status.CvPtr, err.CvPtr, winSize0, maxLevel,
criteria0, (int)flags, minEigThreshold));
GC.KeepAlive(prevImg);
GC.KeepAlive(nextImg);
GC.KeepAlive(prevPts);
nextPts.Fix();
status.Fix();
err.Fix();
}
/// <summary>
/// computes sparse optical flow using multi-scale Lucas-Kanade algorithm
/// </summary>
/// <param name="prevImg"></param>
/// <param name="nextImg"></param>
/// <param name="prevPts"></param>
/// <param name="nextPts"></param>
/// <param name="status"></param>
/// <param name="err"></param>
/// <param name="winSize"></param>
/// <param name="maxLevel"></param>
/// <param name="criteria"></param>
/// <param name="flags"></param>
/// <param name="minEigThreshold"></param>
public static void CalcOpticalFlowPyrLK(
InputArray prevImg,
InputArray nextImg,
Point2f[] prevPts,
ref Point2f[] nextPts,
out byte[] status,
out float[] err,
Size?winSize = null,
int maxLevel = 3,
TermCriteria?criteria = null,
OpticalFlowFlags flags = OpticalFlowFlags.None,
double minEigThreshold = 1e-4)
{
if (prevImg == null)
{
throw new ArgumentNullException(nameof(prevImg));
}
if (nextImg == null)
{
throw new ArgumentNullException(nameof(nextImg));
}
if (prevPts == null)
{
throw new ArgumentNullException(nameof(prevPts));
}
if (nextPts == null)
{
throw new ArgumentNullException(nameof(nextPts));
}
prevImg.ThrowIfDisposed();
nextImg.ThrowIfDisposed();
var winSize0 = winSize.GetValueOrDefault(new Size(21, 21));
var criteria0 = criteria.GetValueOrDefault(
TermCriteria.Both(30, 0.01));
using var nextPtsVec = new VectorOfPoint2f(nextPts);
using var statusVec = new VectorOfByte();
using var errVec = new VectorOfFloat();
NativeMethods.HandleException(
NativeMethods.video_calcOpticalFlowPyrLK_vector(
prevImg.CvPtr, nextImg.CvPtr, prevPts, prevPts.Length,
nextPtsVec.CvPtr, statusVec.CvPtr, errVec.CvPtr,
winSize0, maxLevel, criteria0, (int)flags, minEigThreshold));
GC.KeepAlive(prevImg);
GC.KeepAlive(nextImg);
nextPts = nextPtsVec.ToArray();
status = statusVec.ToArray();
err = errVec.ToArray();
}