#include <vector>
#include "opencv2/core.hpp"
-#include <opencv2/core/utility.hpp>
+#include "opencv2/core/utility.hpp"
#include "opencv2/imgproc.hpp"
#include "opencv2/highgui.hpp"
#include "opencv2/video.hpp"
#include "opencv2/cudaoptflow.hpp"
#include "opencv2/cudaimgproc.hpp"
+#include "opencv2/cudaarithm.hpp"
using namespace std;
using namespace cv;
}
}
+inline bool isFlowCorrect(Point2f u)
+{
+ return !cvIsNaN(u.x) && !cvIsNaN(u.y) && fabs(u.x) < 1e9 && fabs(u.y) < 1e9;
+}
+
+static Vec3b computeColor(float fx, float fy)
+{
+ static bool first = true;
+
+ // relative lengths of color transitions:
+ // these are chosen based on perceptual similarity
+ // (e.g. one can distinguish more shades between red and yellow
+ // than between yellow and green)
+ const int RY = 15;
+ const int YG = 6;
+ const int GC = 4;
+ const int CB = 11;
+ const int BM = 13;
+ const int MR = 6;
+ const int NCOLS = RY + YG + GC + CB + BM + MR;
+ static Vec3i colorWheel[NCOLS];
+
+ if (first)
+ {
+ int k = 0;
+
+ for (int i = 0; i < RY; ++i, ++k)
+ colorWheel[k] = Vec3i(255, 255 * i / RY, 0);
+
+ for (int i = 0; i < YG; ++i, ++k)
+ colorWheel[k] = Vec3i(255 - 255 * i / YG, 255, 0);
+
+ for (int i = 0; i < GC; ++i, ++k)
+ colorWheel[k] = Vec3i(0, 255, 255 * i / GC);
+
+ for (int i = 0; i < CB; ++i, ++k)
+ colorWheel[k] = Vec3i(0, 255 - 255 * i / CB, 255);
+
+ for (int i = 0; i < BM; ++i, ++k)
+ colorWheel[k] = Vec3i(255 * i / BM, 0, 255);
+
+ for (int i = 0; i < MR; ++i, ++k)
+ colorWheel[k] = Vec3i(255, 0, 255 - 255 * i / MR);
+
+ first = false;
+ }
+
+ const float rad = sqrt(fx * fx + fy * fy);
+ const float a = atan2(-fy, -fx) / (float)CV_PI;
+
+ const float fk = (a + 1.0f) / 2.0f * (NCOLS - 1);
+ const int k0 = static_cast<int>(fk);
+ const int k1 = (k0 + 1) % NCOLS;
+ const float f = fk - k0;
+
+ Vec3b pix;
+
+ for (int b = 0; b < 3; b++)
+ {
+ const float col0 = colorWheel[k0][b] / 255.0f;
+ const float col1 = colorWheel[k1][b] / 255.0f;
+
+ float col = (1 - f) * col0 + f * col1;
+
+ if (rad <= 1)
+ col = 1 - rad * (1 - col); // increase saturation with radius
+ else
+ col *= .75; // out of range
+
+ pix[2 - b] = static_cast<uchar>(255.0 * col);
+ }
+
+ return pix;
+}
+
+static void drawOpticalFlow(const Mat_<float>& flowx, const Mat_<float>& flowy, Mat& dst, float maxmotion = -1)
+{
+ dst.create(flowx.size(), CV_8UC3);
+ dst.setTo(Scalar::all(0));
+
+ // determine motion range:
+ float maxrad = maxmotion;
+
+ if (maxmotion <= 0)
+ {
+ maxrad = 1;
+ for (int y = 0; y < flowx.rows; ++y)
+ {
+ for (int x = 0; x < flowx.cols; ++x)
+ {
+ Point2f u(flowx(y, x), flowy(y, x));
+
+ if (!isFlowCorrect(u))
+ continue;
+
+ maxrad = max(maxrad, sqrt(u.x * u.x + u.y * u.y));
+ }
+ }
+ }
+
+ for (int y = 0; y < flowx.rows; ++y)
+ {
+ for (int x = 0; x < flowx.cols; ++x)
+ {
+ Point2f u(flowx(y, x), flowy(y, x));
+
+ if (isFlowCorrect(u))
+ dst.at<Vec3b>(y, x) = computeColor(u.x / maxrad, u.y / maxrad);
+ }
+ }
+}
+
+static void showFlow(const char* name, const GpuMat& d_flow)
+{
+ GpuMat planes[2];
+ cuda::split(d_flow, planes);
+
+ Mat flowx(planes[0]);
+ Mat flowy(planes[1]);
+
+ Mat out;
+ drawOpticalFlow(flowx, flowy, out, 10);
+
+ imshow(name, out);
+}
+
template <typename T> inline T clamp (T x, T a, T b)
{
return ((x) > (a) ? ((x) < (b) ? (x) : (b)) : (a));
// Sparse
- Ptr<cuda::SparsePyrLKOpticalFlow> d_pyrLK = cuda::SparsePyrLKOpticalFlow::create(
+ Ptr<cuda::SparsePyrLKOpticalFlow> d_pyrLK_sparse = cuda::SparsePyrLKOpticalFlow::create(
Size(winSize, winSize), maxLevel, iters);
GpuMat d_frame0(frame0);
GpuMat d_nextPts;
GpuMat d_status;
- d_pyrLK->calc(useGray ? d_frame0Gray : d_frame0, useGray ? d_frame1Gray : d_frame1, d_prevPts, d_nextPts, d_status);
+ d_pyrLK_sparse->calc(useGray ? d_frame0Gray : d_frame0, useGray ? d_frame1Gray : d_frame1, d_prevPts, d_nextPts, d_status);
+
+ // Dense
+
+ Ptr<cuda::DensePyrLKOpticalFlow> d_pyrLK_dense = cuda::DensePyrLKOpticalFlow::create(
+ Size(winSize, winSize), maxLevel, iters);
+
+ GpuMat d_flow(frame0.size(), CV_32FC2);
+
+ d_pyrLK_dense->calc(d_frame0Gray, d_frame1Gray, d_flow);
// Draw arrows
download(d_status, status);
drawArrows(frame0, prevPts, nextPts, status, Scalar(255, 0, 0));
-
imshow("PyrLK [Sparse]", frame0);
+ // Draw flows
+
+ showFlow("PyrLK [Dense] Flow Field", d_flow);
+
waitKey();
return 0;